Commit Graph

6424 Commits

Author SHA1 Message Date
Michal Simek
8da1a3940d Revert "serial: uartps: Use the same dynamic major number for all ports"
This reverts commit ab26266601.

As Johan says, this driver needs a lot more work and these changes are
only going in the wrong direction:
  https://lkml.kernel.org/r/20190523091839.GC568@localhost

Reported-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/14a565fc1e14a5ec6cc6a6710deb878ae8305f22.1585905873.git.michal.simek@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-16 16:00:48 +02:00
Michal Simek
2e01911b7c Revert "serial: uartps: Fix uartps_major handling"
This reverts commit 5e9bd2d70a.

As Johan says, this driver needs a lot more work and these changes are
only going in the wrong direction:
    https://lkml.kernel.org/r/20190523091839.GC568@localhost

Reported-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/310999ab5342f788a7bc1b0e68294d4f052cad07.1585905873.git.michal.simek@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-04-16 16:00:48 +02:00
Linus Torvalds
d38c07afc3 powerpc updates for 5.7
- A large series from Nick for 64-bit to further rework our exception vectors,
    and rewrite portions of the syscall entry/exit and interrupt return in C. The
    result is much easier to follow code that is also faster in general.
 
  - Cleanup of our ptrace code to split various parts out that had become badly
    intertwined with #ifdefs over the years.
 
  - Changes to our NUMA setup under the PowerVM hypervisor which should
    hopefully avoid non-sensical topologies which can lead to warnings from the
    workqueue code and other problems.
 
  - MAINTAINERS updates to remove some of our old orphan entries and update the
    status of others.
 
  - Quite a few other small changes and fixes all over the map.
 
 Thanks to:
   Abdul Haleem, afzal mohammed, Alexey Kardashevskiy, Andrew Donnellan, Aneesh
   Kumar K.V, Balamuruhan S, Cédric Le Goater, Chen Zhou, Christophe JAILLET,
   Christophe Leroy, Christoph Hellwig, Clement Courbet, Daniel Axtens, David
   Gibson, Douglas Miller, Fabiano Rosas, Fangrui Song, Ganesh Goudar, Gautham R.
   Shenoy, Greg Kroah-Hartman, Greg Kurz, Gustavo Luiz Duarte, Hari Bathini, Ilie
   Halip, Jan Kara, Joe Lawrence, Joe Perches, Kajol Jain, Larry Finger,
   Laurentiu Tudor, Leonardo Bras, Libor Pechacek, Madhavan Srinivasan, Mahesh
   Salgaonkar, Masahiro Yamada, Masami Hiramatsu, Mauricio Faria de Oliveira,
   Michael Neuling, Michal Suchanek, Mike Rapoport, Nageswara R Sastry, Nathan
   Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Nick Desaulniers,
   Oliver O'Halloran, Po-Hsu Lin, Pratik Rajesh Sampat, Rasmus Villemoes, Ravi
   Bangoria, Roman Bolshakov, Sam Bobroff, Sandipan Das, Santosh S, Sedat Dilek,
   Segher Boessenkool, Shilpasri G Bhat, Sourabh Jain, Srikar Dronamraju, Stephen
   Rothwell, Tyrel Datwyler, Vaibhav Jain, YueHaibing.
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Merge tag 'powerpc-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux

Pull powerpc updates from Michael Ellerman:
 "Slightly late as I had to rebase mid-week to insert a bug fix:

   - A large series from Nick for 64-bit to further rework our exception
     vectors, and rewrite portions of the syscall entry/exit and
     interrupt return in C. The result is much easier to follow code
     that is also faster in general.

   - Cleanup of our ptrace code to split various parts out that had
     become badly intertwined with #ifdefs over the years.

   - Changes to our NUMA setup under the PowerVM hypervisor which should
     hopefully avoid non-sensical topologies which can lead to warnings
     from the workqueue code and other problems.

   - MAINTAINERS updates to remove some of our old orphan entries and
     update the status of others.

   - Quite a few other small changes and fixes all over the map.

  Thanks to: Abdul Haleem, afzal mohammed, Alexey Kardashevskiy, Andrew
  Donnellan, Aneesh Kumar K.V, Balamuruhan S, Cédric Le Goater, Chen
  Zhou, Christophe JAILLET, Christophe Leroy, Christoph Hellwig, Clement
  Courbet, Daniel Axtens, David Gibson, Douglas Miller, Fabiano Rosas,
  Fangrui Song, Ganesh Goudar, Gautham R. Shenoy, Greg Kroah-Hartman,
  Greg Kurz, Gustavo Luiz Duarte, Hari Bathini, Ilie Halip, Jan Kara,
  Joe Lawrence, Joe Perches, Kajol Jain, Larry Finger, Laurentiu Tudor,
  Leonardo Bras, Libor Pechacek, Madhavan Srinivasan, Mahesh Salgaonkar,
  Masahiro Yamada, Masami Hiramatsu, Mauricio Faria de Oliveira, Michael
  Neuling, Michal Suchanek, Mike Rapoport, Nageswara R Sastry, Nathan
  Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Nick
  Desaulniers, Oliver O'Halloran, Po-Hsu Lin, Pratik Rajesh Sampat,
  Rasmus Villemoes, Ravi Bangoria, Roman Bolshakov, Sam Bobroff,
  Sandipan Das, Santosh S, Sedat Dilek, Segher Boessenkool, Shilpasri G
  Bhat, Sourabh Jain, Srikar Dronamraju, Stephen Rothwell, Tyrel
  Datwyler, Vaibhav Jain, YueHaibing"

* tag 'powerpc-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (158 commits)
  powerpc: Make setjmp/longjmp signature standard
  powerpc/cputable: Remove unnecessary copy of cpu_spec->oprofile_type
  powerpc: Suppress .eh_frame generation
  powerpc: Drop -fno-dwarf2-cfi-asm
  powerpc/32: drop unused ISA_DMA_THRESHOLD
  powerpc/powernv: Add documentation for the opal sensor_groups sysfs interfaces
  selftests/powerpc: Fix try-run when source tree is not writable
  powerpc/vmlinux.lds: Explicitly retain .gnu.hash
  powerpc/ptrace: move ptrace_triggered() into hw_breakpoint.c
  powerpc/ptrace: create ppc_gethwdinfo()
  powerpc/ptrace: create ptrace_get_debugreg()
  powerpc/ptrace: split out ADV_DEBUG_REGS related functions.
  powerpc/ptrace: move register viewing functions out of ptrace.c
  powerpc/ptrace: split out TRANSACTIONAL_MEM related functions.
  powerpc/ptrace: split out SPE related functions.
  powerpc/ptrace: split out ALTIVEC related functions.
  powerpc/ptrace: split out VSX related functions.
  powerpc/ptrace: drop PARAMETER_SAVE_AREA_OFFSET
  powerpc/ptrace: drop unnecessary #ifdefs CONFIG_PPC64
  powerpc/ptrace: remove unused header includes
  ...
2020-04-05 11:12:59 -07:00
Linus Torvalds
0ad5b053d4 Char/Misc driver patches for 5.7-rc1
Here is the big set of char/misc/other driver patches for 5.7-rc1.
 
 Lots of things in here, and it's later than expected due to some reverts
 to resolve some reported issues.  All is now clean with no reported
 problems in linux-next.
 
 Included in here is:
 	- interconnect updates
 	- mei driver updates
 	- uio updates
 	- nvmem driver updates
 	- soundwire updates
 	- binderfs updates
 	- coresight updates
 	- habanalabs updates
 	- mhi new bus type and core
 	- extcon driver updates
 	- some Kconfig cleanups
 	- other small misc driver cleanups and updates
 
 As mentioned, all have been in linux-next for a while, and with the last
 two reverts, all is calm and good.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'char-misc-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc driver updates from Greg KH:
 "Here is the big set of char/misc/other driver patches for 5.7-rc1.

  Lots of things in here, and it's later than expected due to some
  reverts to resolve some reported issues. All is now clean with no
  reported problems in linux-next.

  Included in here is:
   - interconnect updates
   - mei driver updates
   - uio updates
   - nvmem driver updates
   - soundwire updates
   - binderfs updates
   - coresight updates
   - habanalabs updates
   - mhi new bus type and core
   - extcon driver updates
   - some Kconfig cleanups
   - other small misc driver cleanups and updates

  As mentioned, all have been in linux-next for a while, and with the
  last two reverts, all is calm and good"

* tag 'char-misc-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (174 commits)
  Revert "driver core: platform: Initialize dma_parms for platform devices"
  Revert "amba: Initialize dma_parms for amba devices"
  amba: Initialize dma_parms for amba devices
  driver core: platform: Initialize dma_parms for platform devices
  bus: mhi: core: Drop the references to mhi_dev in mhi_destroy_device()
  bus: mhi: core: Initialize bhie field in mhi_cntrl for RDDM capture
  bus: mhi: core: Add support for reading MHI info from device
  misc: rtsx: set correct pcr_ops for rts522A
  speakup: misc: Use dynamic minor numbers for speakup devices
  mei: me: add cedar fork device ids
  coresight: do not use the BIT() macro in the UAPI header
  Documentation: provide IBM contacts for embargoed hardware
  nvmem: core: remove nvmem_sysfs_get_groups()
  nvmem: core: use is_bin_visible for permissions
  nvmem: core: use device_register and device_unregister
  nvmem: core: add root_only member to nvmem device struct
  extcon: axp288: Add wakeup support
  extcon: Mark extcon_get_edev_name() function as exported symbol
  extcon: palmas: Hide error messages if gpio returns -EPROBE_DEFER
  dt-bindings: extcon: usbc-cros-ec: convert extcon-usbc-cros-ec.txt to yaml format
  ...
2020-04-03 13:22:40 -07:00
Linus Torvalds
1f944f976d TTY/Serial patches for 5.7-rc1
Here is the big set of TTY / Serial patches for 5.7-rc1
 
 Lots of console fixups and reworking in here, serial core tweaks
 (doesn't that ever get old, why are we still creating new serial
 devices?), serial driver updates, line-protocol driver updates, and some
 vt cleanups and fixes included in here as well.
 
 All have been in linux-next with no reported issues.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial updates from Greg KH:
 "Here is the big set of TTY / Serial patches for 5.7-rc1

  Lots of console fixups and reworking in here, serial core tweaks
  (doesn't that ever get old, why are we still creating new serial
  devices?), serial driver updates, line-protocol driver updates, and
  some vt cleanups and fixes included in here as well.

  All have been in linux-next with no reported issues"

* tag 'tty-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (161 commits)
  serial: 8250: Optimize irq enable after console write
  serial: 8250: Fix rs485 delay after console write
  vt: vt_ioctl: fix use-after-free in vt_in_use()
  vt: vt_ioctl: fix VT_DISALLOCATE freeing in-use virtual console
  tty: serial: make SERIAL_SPRD depend on COMMON_CLK
  tty: serial: fsl_lpuart: fix return value checking
  tty: serial: fsl_lpuart: move dma_request_chan()
  ARM: dts: tango4: Make /serial compatible with ns16550a
  ARM: dts: mmp*: Make the serial ports compatible with xscale-uart
  ARM: dts: mmp*: Fix serial port names
  ARM: dts: mmp2-brownstone: Don't redeclare phandle references
  ARM: dts: pxa*: Make the serial ports compatible with xscale-uart
  ARM: dts: pxa*: Fix serial port names
  ARM: dts: pxa*: Don't redeclare phandle references
  serial: omap: drop unused dt-bindings header
  serial: 8250: 8250_omap: Add DMA support for UARTs on K3 SoCs
  serial: 8250: 8250_omap: Work around errata causing spurious IRQs with DMA
  serial: 8250: 8250_omap: Extend driver data to pass FIFO trigger info
  serial: 8250: 8250_omap: Move locking out from __dma_rx_do_complete()
  serial: 8250: 8250_omap: Account for data in flight during DMA teardown
  ...
2020-03-31 16:18:55 -07:00
Rafael J. Wysocki
8f1073ed8c Merge branch 'pm-qos'
* pm-qos: (30 commits)
  PM: QoS: annotate data races in pm_qos_*_value()
  Documentation: power: fix pm_qos_interface.rst format warning
  PM: QoS: Make CPU latency QoS depend on CONFIG_CPU_IDLE
  Documentation: PM: QoS: Update to reflect previous code changes
  PM: QoS: Update file information comments
  PM: QoS: Drop PM_QOS_CPU_DMA_LATENCY and rename related functions
  sound: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: usb: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: tty: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: spi: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: net: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: mmc: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: media: Call cpu_latency_qos_*() instead of pm_qos_*()
  drivers: hsi: Call cpu_latency_qos_*() instead of pm_qos_*()
  drm: i915: Call cpu_latency_qos_*() instead of pm_qos_*()
  x86: platform: iosf_mbi: Call cpu_latency_qos_*() instead of pm_qos_*()
  cpuidle: Call cpu_latency_qos_limit() instead of pm_qos_request()
  PM: QoS: Add CPU latency QoS API wrappers
  PM: QoS: Adjust pm_qos_request() signature and reorder pm_qos.h
  PM: QoS: Simplify definitions of CPU latency QoS trace events
  ...
2020-03-30 14:45:57 +02:00
Lukas Wunner
8d5b305484 serial: 8250: Optimize irq enable after console write
Commit 7f9803072f ("serial: 8250: Support console on software emulated
rs485 ports") amended serial8250_console_write() with rs485 support, but
positioned the invocation of ->rs485_stop_tx() after re-enablement of
interrupts.  The irq handler and ->console_write() are serialized with
the port spinlock, so no problem there, but due to the rs485 delay, the
irq handler may unnecessarily spin for a while.  Avoid that by moving
->rs485_stop_tx() before re-enablement of interrupts, which also mirrors
the order at the beginning of serial8250_console_write().

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/019839cb1f61b01210b6ff9ac9f9079ca77f8411.1585319447.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-27 15:45:54 +01:00
Lukas Wunner
4e36f94e99 serial: 8250: Fix rs485 delay after console write
Due to a silly copy-paste mistake, commit 7f9803072f ("serial: 8250:
Support console on software emulated rs485 ports") erroneously pauses
for the duration of delay_rts_before_send after writing to the console,
instead of delay_rts_after_send.  Mea culpa.

Fixes: 7f9803072f ("serial: 8250: Support console on software emulated rs485 ports")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Link: https://lore.kernel.org/r/9dd67f33c90d23f7fafa3b81b1e812ddabf9ca24.1585319447.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-27 15:45:54 +01:00
Eric Biggers
7cf64b18b0 vt: vt_ioctl: fix use-after-free in vt_in_use()
vt_in_use() dereferences console_driver->ttys[i] without proper locking.
This is broken because the tty can be closed and freed concurrently.

We could fix this by using 'READ_ONCE(console_driver->ttys[i]) != NULL'
and skipping the check of tty_struct::count.  But, looking at
console_driver->ttys[i] isn't really appropriate anyway because even if
it is NULL the tty can still be in the process of being closed.

Instead, fix it by making vt_in_use() require console_lock() and check
whether the vt is allocated and has port refcount > 1.  This works since
following the patch "vt: vt_ioctl: fix VT_DISALLOCATE freeing in-use
virtual console" the port refcount is incremented while the vt is open.

Reproducer (very unreliable, but it worked for me after a few minutes):

	#include <fcntl.h>
	#include <linux/vt.h>

	int main()
	{
		int fd, nproc;
		struct vt_stat state;
		char ttyname[16];

		fd = open("/dev/tty10", O_RDONLY);
		for (nproc = 1; nproc < 8; nproc *= 2)
			fork();
		for (;;) {
			sprintf(ttyname, "/dev/tty%d", rand() % 8);
			close(open(ttyname, O_RDONLY));
			ioctl(fd, VT_GETSTATE, &state);
		}
	}

KASAN report:

	BUG: KASAN: use-after-free in vt_in_use drivers/tty/vt/vt_ioctl.c:48 [inline]
	BUG: KASAN: use-after-free in vt_ioctl+0x1ad3/0x1d70 drivers/tty/vt/vt_ioctl.c:657
	Read of size 4 at addr ffff888065722468 by task syz-vt2/132

	CPU: 0 PID: 132 Comm: syz-vt2 Not tainted 5.6.0-rc5-00130-g089b6d3654916 #13
	Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20191223_100556-anatol 04/01/2014
	Call Trace:
	 [...]
	 vt_in_use drivers/tty/vt/vt_ioctl.c:48 [inline]
	 vt_ioctl+0x1ad3/0x1d70 drivers/tty/vt/vt_ioctl.c:657
	 tty_ioctl+0x9db/0x11b0 drivers/tty/tty_io.c:2660
	 [...]

	Allocated by task 136:
	 [...]
	 kzalloc include/linux/slab.h:669 [inline]
	 alloc_tty_struct+0x96/0x8a0 drivers/tty/tty_io.c:2982
	 tty_init_dev+0x23/0x350 drivers/tty/tty_io.c:1334
	 tty_open_by_driver drivers/tty/tty_io.c:1987 [inline]
	 tty_open+0x3ca/0xb30 drivers/tty/tty_io.c:2035
	 [...]

	Freed by task 41:
	 [...]
	 kfree+0xbf/0x200 mm/slab.c:3757
	 free_tty_struct+0x8d/0xb0 drivers/tty/tty_io.c:177
	 release_one_tty+0x22d/0x2f0 drivers/tty/tty_io.c:1468
	 process_one_work+0x7f1/0x14b0 kernel/workqueue.c:2264
	 worker_thread+0x8b/0xc80 kernel/workqueue.c:2410
	 [...]

Fixes: 4001d7b7fc ("vt: push down the tty lock so we can see what is left to tackle")
Cc: <stable@vger.kernel.org> # v3.4+
Acked-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20200322034305.210082-3-ebiggers@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-27 12:35:04 +01:00
Eric Biggers
ca4463bf84 vt: vt_ioctl: fix VT_DISALLOCATE freeing in-use virtual console
The VT_DISALLOCATE ioctl can free a virtual console while tty_release()
is still running, causing a use-after-free in con_shutdown().  This
occurs because VT_DISALLOCATE considers a virtual console's
'struct vc_data' to be unused as soon as the corresponding tty's
refcount hits 0.  But actually it may be still being closed.

Fix this by making vc_data be reference-counted via the embedded
'struct tty_port'.  A newly allocated virtual console has refcount 1.
Opening it for the first time increments the refcount to 2.  Closing it
for the last time decrements the refcount (in tty_operations::cleanup()
so that it happens late enough), as does VT_DISALLOCATE.

Reproducer:
	#include <fcntl.h>
	#include <linux/vt.h>
	#include <sys/ioctl.h>
	#include <unistd.h>

	int main()
	{
		if (fork()) {
			for (;;)
				close(open("/dev/tty5", O_RDWR));
		} else {
			int fd = open("/dev/tty10", O_RDWR);

			for (;;)
				ioctl(fd, VT_DISALLOCATE, 5);
		}
	}

KASAN report:
	BUG: KASAN: use-after-free in con_shutdown+0x76/0x80 drivers/tty/vt/vt.c:3278
	Write of size 8 at addr ffff88806a4ec108 by task syz_vt/129

	CPU: 0 PID: 129 Comm: syz_vt Not tainted 5.6.0-rc2 #11
	Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20191223_100556-anatol 04/01/2014
	Call Trace:
	 [...]
	 con_shutdown+0x76/0x80 drivers/tty/vt/vt.c:3278
	 release_tty+0xa8/0x410 drivers/tty/tty_io.c:1514
	 tty_release_struct+0x34/0x50 drivers/tty/tty_io.c:1629
	 tty_release+0x984/0xed0 drivers/tty/tty_io.c:1789
	 [...]

	Allocated by task 129:
	 [...]
	 kzalloc include/linux/slab.h:669 [inline]
	 vc_allocate drivers/tty/vt/vt.c:1085 [inline]
	 vc_allocate+0x1ac/0x680 drivers/tty/vt/vt.c:1066
	 con_install+0x4d/0x3f0 drivers/tty/vt/vt.c:3229
	 tty_driver_install_tty drivers/tty/tty_io.c:1228 [inline]
	 tty_init_dev+0x94/0x350 drivers/tty/tty_io.c:1341
	 tty_open_by_driver drivers/tty/tty_io.c:1987 [inline]
	 tty_open+0x3ca/0xb30 drivers/tty/tty_io.c:2035
	 [...]

	Freed by task 130:
	 [...]
	 kfree+0xbf/0x1e0 mm/slab.c:3757
	 vt_disallocate drivers/tty/vt/vt_ioctl.c:300 [inline]
	 vt_ioctl+0x16dc/0x1e30 drivers/tty/vt/vt_ioctl.c:818
	 tty_ioctl+0x9db/0x11b0 drivers/tty/tty_io.c:2660
	 [...]

Fixes: 4001d7b7fc ("vt: push down the tty lock so we can see what is left to tackle")
Cc: <stable@vger.kernel.org> # v3.4+
Reported-by: syzbot+522643ab5729b0421998@syzkaller.appspotmail.com
Acked-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20200322034305.210082-2-ebiggers@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-27 12:35:04 +01:00
Chunyan Zhang
3b9c55efb2 tty: serial: make SERIAL_SPRD depend on COMMON_CLK
kbuild-test reported an error:

  config: mips-randconfig-a001-20200321 ...
  >> drivers/tty/serial/sprd_serial.c:1175: undefined reference
  to `clk_set_parent'

Because some mips Kconfig selects HAVE_CLK but not COMMON_CLK and no
clk_set_parent implemented, so the error was exposed. So adding
dependence on COMMON_CLK can fix this issue.

Fixes: 7ba87cfec7 ("tty: serial: make SERIAL_SPRD not depend on ARCH_SPRD")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com>
Link: https://lore.kernel.org/r/20200325081427.20312-1-zhang.lyra@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-26 15:41:03 +01:00
Michael Walle
d7c53fb081 tty: serial: fsl_lpuart: fix return value checking
The return value of lpuart_dma_tx_request() is an negative errno on
failure and zero on success.

Fixes: 159381df14 ("tty: serial: fsl_lpuart: fix DMA operation when using IOMMU")
Reported-by: Leonard Crestez <leonard.crestez@nxp.com>
Signed-off-by: Michael Walle <michael@walle.cc>
Reviewed-by: Fugang Duan <fugang.duan@nxp.com>
Link: https://lore.kernel.org/r/20200325090658.25967-2-michael@walle.cc
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-26 15:34:05 +01:00
Michael Walle
d0e7600b91 tty: serial: fsl_lpuart: move dma_request_chan()
Move dma_request_chan() out of the atomic context. First this call
should not be in the atomic context at all and second the
dev_info_once() may cause a hang because because the console takes this
spinlock, too.

Fixes: 159381df14 ("tty: serial: fsl_lpuart: fix DMA operation when using IOMMU")
Reported-by: Leonard Crestez <leonard.crestez@nxp.com>
Signed-off-by: Michael Walle <michael@walle.cc>
Reviewed-by: Fugang Duan <fugang.duan@nxp.com>
Tested-by: Leonard Crestez <leonard.crestez@nxp.com>
Link: https://lore.kernel.org/r/20200325090658.25967-1-michael@walle.cc
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-26 15:34:05 +01:00
Uwe Kleine-König
c97c65f36e serial: omap: drop unused dt-bindings header
The definitons in the dt-binding's gpio header only contains some
constants to be used in device trees. It is not relevant for omap-serial
(as the gpio API hides the details) and in fact unused so it can just be
dropped.

Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org>
Link: https://lore.kernel.org/r/20200321204031.30369-1-uwe@kleine-koenig.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24 12:26:11 +01:00
Vignesh Raghavendra
c26389f998 serial: 8250: 8250_omap: Add DMA support for UARTs on K3 SoCs
UART on K3 SoCs has configurable RX timeout behavior (controlled via
EFR2) and better DMA integration. This allows to transfer as larger
amount data per DMA transfer compared to older SoCs.  Add support for
the same.

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20200319110344.21348-7-vigneshr@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24 12:25:11 +01:00
Vignesh Raghavendra
c6689dfd87 serial: 8250: 8250_omap: Work around errata causing spurious IRQs with DMA
As per Advisory 27 of AM437x Silicon errata document, Spurious UART
interrupts may occur when DMA mode (FCR.DMA_MODE) is enabled. The
Interrupt Controller flags that a UART interrupt has occurred; however,
the associated IT_PENDING bit remains set to 1, indicating that no
interrupt is pending. Acknowledge the spurious interrupts for every
occurrence as workaround.

Errata is applicable to all TI SoCs with this IP.

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20200319110344.21348-6-vigneshr@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24 12:25:11 +01:00
Vignesh Raghavendra
7229b84c20 serial: 8250: 8250_omap: Extend driver data to pass FIFO trigger info
Although same 8250 compliant UART IP is reused across different SoC,
their integration wrt DMA varies greatly across SoCs. Therefore,
different SoC may need to use different FIFO trigger level for DMA
event and DMA configuration parameters. Provide a way to pass this
information via driver data. This is required to support UART DMA on
AM654/J721e SoCs.

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20200319110344.21348-5-vigneshr@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24 12:25:10 +01:00
Peter Ujfalusi
7898984167 serial: 8250: 8250_omap: Move locking out from __dma_rx_do_complete()
Caller functions of __dma_rx_do_complete() already hold rx_dma_lock.
Therefore move locking out of the function to avoid need to release and
reacquire lock.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20200319110344.21348-4-vigneshr@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24 12:25:10 +01:00
Vignesh Raghavendra
4bcf59a5de serial: 8250: 8250_omap: Account for data in flight during DMA teardown
Take into account data stuck in DMA internal buffers before pushing data
to higher layer. dma_tx_state has "in_flight_bytes" member that provides
this information.

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20200319110344.21348-3-vigneshr@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24 12:25:10 +01:00
Vignesh Raghavendra
7cf4df30a9 serial: 8250: 8250_omap: Terminate DMA before pushing data on RX timeout
Terminate and flush DMA internal buffers, before pushing RX data to
higher layer. Otherwise, this will lead to data corruption, as driver
would end up pushing stale buffer data to higher layer while actual data
is still stuck inside DMA hardware and has yet not arrived at the
memory.
While at that, replace deprecated dmaengine_terminate_all() with
dmaengine_terminate_async().

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20200319110344.21348-2-vigneshr@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24 12:25:10 +01:00
Peter Ujfalusi
4ce35a3617 serial: 8250_omap: Fix sleeping function called from invalid context during probe
When booting j721e the following bug is printed:

[    1.154821] BUG: sleeping function called from invalid context at kernel/sched/completion.c:99
[    1.154827] in_atomic(): 0, irqs_disabled(): 128, non_block: 0, pid: 12, name: kworker/0:1
[    1.154832] 3 locks held by kworker/0:1/12:
[    1.154836]  #0: ffff000840030728 ((wq_completion)events){+.+.}, at: process_one_work+0x1d4/0x6e8
[    1.154852]  #1: ffff80001214fdd8 (deferred_probe_work){+.+.}, at: process_one_work+0x1d4/0x6e8
[    1.154860]  #2: ffff00084060b170 (&dev->mutex){....}, at: __device_attach+0x38/0x138
[    1.154872] irq event stamp: 63096
[    1.154881] hardirqs last  enabled at (63095): [<ffff800010b74318>] _raw_spin_unlock_irqrestore+0x70/0x78
[    1.154887] hardirqs last disabled at (63096): [<ffff800010b740d8>] _raw_spin_lock_irqsave+0x28/0x80
[    1.154893] softirqs last  enabled at (62254): [<ffff800010080c88>] _stext+0x488/0x564
[    1.154899] softirqs last disabled at (62247): [<ffff8000100fdb3c>] irq_exit+0x114/0x140
[    1.154906] CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.6.0-rc6-next-20200318-00094-g45e4089b0bd3 #221
[    1.154911] Hardware name: Texas Instruments K3 J721E SoC (DT)
[    1.154917] Workqueue: events deferred_probe_work_func
[    1.154923] Call trace:
[    1.154928]  dump_backtrace+0x0/0x190
[    1.154933]  show_stack+0x14/0x20
[    1.154940]  dump_stack+0xe0/0x148
[    1.154946]  ___might_sleep+0x150/0x1f0
[    1.154952]  __might_sleep+0x4c/0x80
[    1.154957]  wait_for_completion_timeout+0x40/0x140
[    1.154964]  ti_sci_set_device_state+0xa0/0x158
[    1.154969]  ti_sci_cmd_get_device_exclusive+0x14/0x20
[    1.154977]  ti_sci_dev_start+0x34/0x50
[    1.154984]  genpd_runtime_resume+0x78/0x1f8
[    1.154991]  __rpm_callback+0x3c/0x140
[    1.154996]  rpm_callback+0x20/0x80
[    1.155001]  rpm_resume+0x568/0x758
[    1.155007]  __pm_runtime_resume+0x44/0xb0
[    1.155013]  omap8250_probe+0x2b4/0x508
[    1.155019]  platform_drv_probe+0x50/0xa0
[    1.155023]  really_probe+0xd4/0x318
[    1.155028]  driver_probe_device+0x54/0xe8
[    1.155033]  __device_attach_driver+0x80/0xb8
[    1.155039]  bus_for_each_drv+0x74/0xc0
[    1.155044]  __device_attach+0xdc/0x138
[    1.155049]  device_initial_probe+0x10/0x18
[    1.155053]  bus_probe_device+0x98/0xa0
[    1.155058]  deferred_probe_work_func+0x74/0xb0
[    1.155063]  process_one_work+0x280/0x6e8
[    1.155068]  worker_thread+0x48/0x430
[    1.155073]  kthread+0x108/0x138
[    1.155079]  ret_from_fork+0x10/0x18

To fix the bug we need to first call pm_runtime_enable() prior to any
pm_runtime calls.

Reported-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Link: https://lore.kernel.org/r/20200320125200.6772-1-peter.ujfalusi@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24 12:25:09 +01:00
Vignesh Raghavendra
f4b042a050 serial: 8250: 8250_omap: Fix throttle to call stop_rx()
Call stop_rx() to halt reception when throttle is requested. Update
unthrottle callback to restart reception.

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20200319103230.16867-3-vigneshr@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24 12:25:09 +01:00
Vignesh Raghavendra
f19c3f6c81 serial: 8250_port: Don't service RX FIFO if throttled
When port's throttle callback is called, it should stop pushing any more
data into TTY buffer to avoid buffer overflow. This means driver has to
stop HW from receiving more data and assert the HW flow control. For
UARTs with auto HW flow control (such as 8250_omap) manual assertion of
flow control line is not possible and only way is to allow RX FIFO to
fill up, thus trigger auto HW flow control logic.

Therefore make sure that 8250 generic IRQ handler does not drain data
when port is stopped (i.e UART_LSR_DR is unset in read_status_mask). Not
servicing, RX FIFO would trigger auto HW flow control when FIFO
occupancy reaches preset threshold, thus halting RX.
Since, error conditions in UART_LSR register are cleared just by reading
the register, data has to be drained in case there are FIFO errors, else
error information will lost.

Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com>
Link: https://lore.kernel.org/r/20200319103230.16867-2-vigneshr@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24 12:25:09 +01:00
Raviteja Narayanam
706bbc572d serial: uartps: Add TACTIVE check in cdns_uart_tx_empty function
Make sure that all bytes are transmitted out of Uart by monitoring
CDNS_UART_SR_TACTIVE bit as well.

Signed-off-by: Raviteja Narayanam <raviteja.narayanam@xilinx.com>
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Acked-by: Maarten Brock <m.brock@vanmierlo.com>
Link: https://lore.kernel.org/r/e2514818af5973be291cc117d07739f068b71639.1584610774.git.shubhrajyoti.datta@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24 12:23:04 +01:00
Raviteja Narayanam
97451855cc serial: uartps: Remove unconditional wait inside set_termios
set_termios function should not wait for the transmit FIFO empty
(CDNS_UART_SR_TXEMPTY) unconditionally. The tty layer takes care
of it based on the parameter passed (TCSANOW/TCSADRAIN/TCSAFLUSH).

Signed-off-by: Raviteja Narayanam <raviteja.narayanam@xilinx.com>
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Link: https://lore.kernel.org/r/536e190dd5bbb474007a67e6323c048288942a28.1584610774.git.shubhrajyoti.datta@xilinx.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-24 12:23:03 +01:00
Greg Kroah-Hartman
cbf580ff09 Merge 5.6-rc7 into tty-next
We need the tty fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-23 08:02:55 +01:00
Greg Kroah-Hartman
baca54d956 Merge 5.6-rc7 into char-misc-next
We need the char/misc driver fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-23 07:59:38 +01:00
Eric Biggers
6e622cd8bd tty: fix compat TIOCGSERIAL checking wrong function ptr
Commit 7765435030 ("take compat TIOC[SG]SERIAL treatment into
tty_compat_ioctl()") changed the compat version of TIOCGSERIAL to start
checking for the presence of the ->set_serial function pointer rather
than ->get_serial.  This appears to be a copy-and-paste error, since
->get_serial is the function pointer that is called as well as the
pointer that is checked by the non-compat version of TIOCGSERIAL.

Fix this by checking the correct function pointer.

Fixes: 7765435030 ("take compat TIOC[SG]SERIAL treatment into tty_compat_ioctl()")
Cc: <stable@vger.kernel.org> # v4.20+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200224182044.234553-3-ebiggers@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18 13:15:13 +01:00
Eric Biggers
17329563a9 tty: fix compat TIOCGSERIAL leaking uninitialized memory
Commit 7765435030 ("take compat TIOC[SG]SERIAL treatment into
tty_compat_ioctl()") changed the compat version of TIOCGSERIAL to start
copying a whole 'serial_struct32' to userspace rather than individual
fields, but failed to initialize all padding and fields -- namely the
hole after the 'iomem_reg_shift' field, and the 'reserved' field.

Fix this by initializing the struct to zero.

[v2: use sizeof, and convert the adjacent line for consistency.]

Reported-by: syzbot+8da9175e28eadcb203ce@syzkaller.appspotmail.com
Fixes: 7765435030 ("take compat TIOC[SG]SERIAL treatment into tty_compat_ioctl()")
Cc: <stable@vger.kernel.org> # v4.20+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200224182044.234553-2-ebiggers@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18 13:15:13 +01:00
Eric Biggers
ed069827ca tty: drop outdated comments about release_tty() locking
The current version of the TTY code unlocks the tty_struct(s) before
release_tty() rather than after.  Moreover, tty_unlock_pair() no longer
exists.  Thus, remove the outdated comments regarding tty_unlock_pair().

Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20200224073359.292795-1-ebiggers@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18 13:08:45 +01:00
Nishad Kamdar
db1032f7e4 tty: n_tracesink: Use the correct style for SPDX License Identifier
This patch corrects the SPDX License Identifier style in
header file related to Kernel driver API to route trace data.
For C header files Documentation/process/license-rules.rst
mandates C-like comments (opposed to C source files where
C++ style should be used).

Changes made by using a script provided by Joe Perches here:
https://lkml.org/lkml/2019/2/7/46.

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Nishad Kamdar <nishadkamdar@gmail.com>
Link: https://lore.kernel.org/r/20200302143642.GA3335@nishad
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18 13:01:31 +01:00
Nishad Kamdar
bdc3070e3f tty: hvc: Use the correct style for SPDX License Identifier
This patch corrects the SPDX License Identifier style in
header file related to the HVC driver.
For C header files Documentation/process/license-rules.rst
mandates C-like comments (opposed to C source files where
C++ style should be used).

Changes made by using a script provided by Joe Perches here:
https://lkml.org/lkml/2019/2/7/46.

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Nishad Kamdar <nishadkamdar@gmail.com>
Link: https://lore.kernel.org/r/20200301170419.GA7125@nishad
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18 13:01:05 +01:00
Takashi Iwai
caa47cc639 tty: nozomi: Use scnprintf() for avoiding potential buffer overflow
Since snprintf() returns the would-be-output size instead of the
actual output size, the succeeding calls may go beyond the given
buffer limit.  Fix it by replacing with scnprintf().

Also rewrite the code in a standard if-form instead of ugly
conditional operators.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20200311092905.24362-1-tiwai@suse.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18 12:59:29 +01:00
Takashi Iwai
e39c0ffe8c tty: serial: pch_uart: Use scnprintf() for avoiding potential buffer overflow
Since snprintf() returns the would-be-output size instead of the
actual output size, the succeeding calls may go beyond the given
buffer limit.  Fix it by replacing with scnprintf().

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20200311092930.24433-1-tiwai@suse.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18 12:59:29 +01:00
Alexandre Belloni
e2c2e79871 tty: nozomi: fix spelling mistake "reserverd" -> "reserved"
The reserved bits should be named reserved.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20200214141455.20902-1-alexandre.belloni@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18 12:59:29 +01:00
Chunyan Zhang
7253407747 serial: sprd: remove redundant sprd_port cleanup
We don't need to cleanup sprd_port anymore, since we've dropped the way
of using the sprd_port[] array to get port index.

Reviewed-by: Baolin Wang <baolin.wang7@gmail.com>
Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com>
Link: https://lore.kernel.org/r/20200318105049.19623-3-zhang.lyra@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18 12:20:04 +01:00
Chunyan Zhang
4b7349cb4e serial: sprd: getting port index via serial aliases only
This patch simplifies the process of getting serial port number, with
this patch, serial devices must have aliases configured in devicetree.

The serial port searched out via sprd_port array maybe wrong if we don't
have serial alias defined in devicetree, and specify console with command
line, we would get the wrong port number if other serial ports probe
failed before console's. So using aliases is mandatory.

Reviewed-by: Baolin Wang <baolin.wang7@gmail.com>
Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com>
Link: https://lore.kernel.org/r/20200318105049.19623-2-zhang.lyra@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18 12:20:04 +01:00
Vincent Chen
630db5cbc7 tty: serial: Add CONSOLE_POLL support to SiFive UART
Add CONSOLE_POLL support for future KGDB porting.

Signed-off-by: Vincent Chen <vincent.chen@sifive.com>

Changes since v1:
1. Fix the compile error reported by kbuild test robot
Link: https://lore.kernel.org/r/1584492027-23236-1-git-send-email-vincent.chen@sifive.com

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-18 11:07:13 +01:00
Andy Shevchenko
089b6d3654 serial: 8250_port: Disable DMA operations for kernel console
It would be too tricky and error prone to allow DMA operations on
kernel console.

One of the concern is when DMA is a separate device, for example on
Intel CherryTrail platforms, and might need special work around to be
functional, see the commit

  eebb3e8d8a ("ACPI / LPSS: override power state for LPSS DMA device")

for more information.

Another one is that kernel console is used in atomic context, e.g.
when printing crucial information to the user (Oops or crash),
and DMA may not serve due to power management complications
including non-atomic ACPI calls but not limited to it (see above).

Besides that, other concerns are described in the commit

  84b40e3b57 ("serial: 8250: omap: Disable DMA for console UART")

done for OMAP UART and may be repeated here.

Disable any kind of DMA operations on kernel console due to above concerns.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200217114016.49856-7-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-17 15:58:00 +01:00
Andy Shevchenko
bedb404e91 serial: 8250_port: Don't use power management for kernel console
Doing any kind of power management for kernel console is really bad idea.

First of all, it runs in poll and atomic mode. This fact attaches a limitation
on the functions that might be called. For example, pm_runtime_get_sync() might
sleep and thus can't be used. This call needs, for example, to bring the device
to powered on state on the system, where the power on sequence may require
on-atomic operations, such as Intel Cherrytrail with ACPI enumerated UARTs.
That said, on ACPI enabled platforms it might even call firmware for a job.

On the other hand pm_runtime_get() doesn't guarantee that device will become
powered on fast enough.

Besides that, imagine the case when console is about to print a kernel Oops and
it's powered off. In such an emergency case calling the complex functions is
not the best what we can do, taking into consideration that user wants to see
at least something of the last kernel word before it passes away.

Here we modify the 8250 console code to prevent runtime power management.

Note, there is a behaviour change for OMAP boards. It will require to detach
kernel console to become idle.

Link: https://lists.openwall.net/linux-kernel/2018/09/29/65
Suggested-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200217114016.49856-6-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-17 15:58:00 +01:00
Andy Shevchenko
a3cb39d258 serial: core: Allow detach and attach serial device for console
In the future we would like to disable power management on the serial devices
used as kernel consoles to avoid weird behaviour in some cases. However,
disabling PM may prevent system to go to deep sleep states, which in its turn
leads to the higher power consumption.

Tony Lindgren proposed a work around, i.e. allow user to detach such consoles
to make PM working again. In case user wants to see what's going on, it also
provides a mechanism to attach console back.

Link: https://lists.openwall.net/linux-kernel/2018/09/29/65
Suggested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200217114016.49856-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-17 15:57:59 +01:00
Geert Uytterhoeven
7e13d0a6b1 Revert "tty: serial: samsung_tty: build it for any platform"
This reverts commit 175b558d0e.

When the user configures a kernel without support for Samsung SoCs, it
makes no sense to ask the user about enabling "Samsung SoC serial
support", as Samsung serial ports can only be found on Samsung SoCs.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200306102301.16870-1-geert+renesas@glider.be
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-17 15:22:23 +01:00
Lanqing Liu
efc176929a serial: sprd: Fix a dereference warning
We should validate if the 'sup' is NULL or not before freeing DMA
memory, to fix below warning.

"drivers/tty/serial/sprd_serial.c:1141 sprd_remove()
 error: we previously assumed 'sup' could be null (see line 1132)"

Fixes: f4487db58e ("serial: sprd: Add DMA mode support")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Lanqing Liu <liuhhome@gmail.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/e2bd92691538e95b04a2c2a728f3292e1617018f.1584325957.git.liuhhome@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-17 15:20:41 +01:00
Chunyan Zhang
f1b49d5a07 serial: sprd: remove __init from sprd_console_setup
The function sprd_console_setup() would be called from .probe() which can
be called after freeing __init functions, for example the .probe() would
return -EPROBE_DEFER since it depends on clock modules.

Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com>
Reviewed-by: Baolin Wang <baolin.wang7@gmail.com>
Link: https://lore.kernel.org/r/20200316101930.9962-3-zhang.lyra@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-17 15:20:41 +01:00
Chunyan Zhang
72cc06be19 serial: sprd: check console via stdout-path in addition
The SPRD serial driver need to know which serial port would be used as
console in an early period during initialization, the purpose is to
keep the console port alive as possible even if there's some error
caused by no clock configured under serial devicetree nodes. But with
the patch [1], the console port couldn't be identified if missing
console command line.

So this patch adds using another interface to do check by reading
stdout-path.

[1] https://lore.kernel.org/lkml/20190826072929.7696-4-zhang.lyra@gmail.com/

Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com>
Reviewed-by: Baolin Wang <baolin.wang7@gmail.com>
Link: https://lore.kernel.org/r/20200316101930.9962-2-zhang.lyra@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-17 15:20:41 +01:00
Stephen Rothwell
3670664b5d tty: evh_bytechan: Fix out of bounds accesses
ev_byte_channel_send() assumes that its third argument is a 16 byte
array. Some places where it is called it may not be (or we can't
easily tell if it is). Newer compilers have started producing warnings
about this, so make sure we actually pass a 16 byte array.

There may be more elegant solutions to this, but the driver is quite
old and hasn't been updated in many years.

The warnings (from a powerpc allyesconfig build) are:

  In file included from include/linux/byteorder/big_endian.h:5,
                   from arch/powerpc/include/uapi/asm/byteorder.h:14,
                   from include/asm-generic/bitops/le.h:6,
                   from arch/powerpc/include/asm/bitops.h:250,
                   from include/linux/bitops.h:29,
                   from include/linux/kernel.h:12,
                   from include/asm-generic/bug.h:19,
                   from arch/powerpc/include/asm/bug.h:109,
                   from include/linux/bug.h:5,
                   from include/linux/mmdebug.h:5,
                   from include/linux/gfp.h:5,
                   from include/linux/slab.h:15,
                   from drivers/tty/ehv_bytechan.c:24:
  drivers/tty/ehv_bytechan.c: In function ‘ehv_bc_udbg_putc’:
  arch/powerpc/include/asm/epapr_hcalls.h:298:20: warning: array subscript 1 is outside array bounds of ‘const char[1]’ [-Warray-bounds]
    298 |  r6 = be32_to_cpu(p[1]);
  include/uapi/linux/byteorder/big_endian.h:40:51: note: in definition of macro ‘__be32_to_cpu’
     40 | #define __be32_to_cpu(x) ((__force __u32)(__be32)(x))
        |                                                   ^
  arch/powerpc/include/asm/epapr_hcalls.h:298:7: note: in expansion of macro ‘be32_to_cpu’
    298 |  r6 = be32_to_cpu(p[1]);
        |       ^~~~~~~~~~~
  drivers/tty/ehv_bytechan.c:166:13: note: while referencing ‘data’
    166 | static void ehv_bc_udbg_putc(char c)
        |             ^~~~~~~~~~~~~~~~

Fixes: dcd83aaff1 ("tty/powerpc: introduce the ePAPR embedded hypervisor byte channel driver")
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Tested-by: Laurentiu Tudor <laurentiu.tudor@nxp.com>
[mpe: Trim warnings from change log]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200109183912.5fcb52aa@canb.auug.org.au
2020-03-17 23:40:31 +11:00
Jiri Slaby
c3a834e87c vt: indent switch-case in setterm_command properly
Shift cases one level left. This makes the code more readable and some
lines need not wrap anymore.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200316065911.11024-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-16 08:41:17 +01:00
Jiri Slaby
f0e8e3da22 vt: selection, use rounddown() for start/endline computation
We have a helper called rounddown for these modulo computations. So use
it.

No functional change intended and "objdump -d" proves that.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200316065911.11024-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-16 08:41:17 +01:00
Jiri Slaby
85af37056a vt: use min() to limit intervals
Instead of awkward ternary operator with comparison, use simple min()
for blankinterval and vesa_off_interval.

No functional change intended and "objdump -d" proves that.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200316065911.11024-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-16 08:41:17 +01:00
Jiri Slaby
b18d1c2efa tty: n_hdlc, remove FILE and LINE from pr_debug
As Joe suggests, dynamic debug can print module name and line number
along with message. So remove __FILE__ and __LINE__ from all those
pr_debug calls.

Out of curiosity, I measured the savings, 200 bytes of code are gone.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Suggested-by: Joe Perches <joe@perches.com>
Link: https://lore.kernel.org/r/20200316064910.4941-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-16 08:39:47 +01:00
Jiri Slaby
5b30dee6cc vt: selection, fix double lock introduced by a merge
The merge commit cb05c6c82f (Merge 5.6-rc5 into tty-next) introduced a
double lock to set_selection_kernel. vc_sel.lock is locked both in
set_selection_kernel and its callee __set_selection_kernel now.

Remove the latter.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Link: https://lore.kernel.org/r/20200316064544.4799-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-16 08:39:47 +01:00
Douglas Anderson
d49e7953f9 tty: serial: qcom_geni_serial: Don't try to manually disable the console
The geni serial driver's shutdown code had a special case to call
console_stop().  Grepping through the code, it was the only serial
driver doing something like this (the only other caller of
console_stop() was in serial_core.c).

As far as I can tell there's no reason to call console_stop() in the
geni code.  ...and a good reason _not_ to call it.  Specifically if
you have an agetty running on the same serial port as the console then
killing the agetty kills your console and if you start the agetty
again the console doesn't come back.

Fixes: c4f528795d ("tty: serial: msm_geni_serial: Add serial driver support for GENI based QUP")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200313134635.2.I3648fac6c98b887742934146ac2729ecb7232eb1@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-14 09:40:27 +01:00
Douglas Anderson
e83766334f tty: serial: qcom_geni_serial: No need to stop tx/rx on UART shutdown
On a board using qcom_geni_serial I found that I could no longer
interact with kdb if I got a crash after the "agetty" running on the
same serial port was killed.  This meant that various classes of
crashes that happened at reboot time were undebuggable.

Reading through the code, I couldn't figure out why qcom_geni_serial
felt the need to run so much code at port shutdown time.  All we need
to do is disable the interrupt.

After I make this change then a hardcoded kgdb_breakpoint in some late
shutdown code now allows me to interact with the debugger.  I also
could freely close / re-open the port without problems.

Fixes: c4f528795d ("tty: serial: msm_geni_serial: Add serial driver support for GENI based QUP")
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200313134635.1.Icf54c533065306b02b880c46dfd401d8db34e213@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-14 09:40:27 +01:00
Eric Biggers
1aa6e058dd vt: vt_ioctl: remove unnecessary console allocation checks
The vc_cons_allocated() checks in vt_ioctl() and vt_compat_ioctl() are
unnecessary because they can only be reached by calling ioctl() on an
open tty, which implies the corresponding virtual console is allocated.

And even if the virtual console *could* be freed concurrently, then
these checks would be broken since they aren't done under console_lock,
and the vc_data is dereferenced before them anyway.

So, remove these unneeded checks to avoid confusion.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20200224080326.295046-1-ebiggers@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12 21:43:49 +01:00
Eric Biggers
c57c1644c2 vt: drop redundant might_sleep() in do_con_write()
The might_sleep() in do_con_write() is redundant because console_lock()
already contains might_sleep().  Remove it.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Link: https://lore.kernel.org/r/20200224073450.292892-1-ebiggers@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12 17:36:10 +01:00
Randy Dunlap
2cca608ad9 tty: reorganize tty & serial menus
Move LDISC_AUTOLOAD ahead of the Serial drivers menu.

Move the Serial drivers menu ahead of the Non-standard serial port
support menu.

Move NOZOMI out of the SERIAL_NONSTANDARD area since it does not
depend on SERIAL_NONSTANDARD and it breaks the SERIAL_NONSTANDARD
menu list.

Alphabetize the remaining drivers (in tty/Kconfig) by their prompt strings.
[The drivers in tty/hvc/Kconfig and tty/serial/Kconfig have not
been alphabetized.]

Cc: Jiri Slaby <jslaby@suse.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20200311225736.32147-4-rdunlap@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12 17:17:30 +01:00
Randy Dunlap
00e3754397 tty: source all tty Kconfig files in one place
'source' (include) all of the tty/*/Kconfig files from
drivers/tty/Kconfig instead of from drivers/char/Kconfig.
This consolidates them both in source code and in menu
presentation to the user.

Move hvc/Kconfig and serial/Kconfig 'source' lines into the
if TTY/endif block and remove the if TTY/endif blocks from
those 2 files.

Cc: linux-serial@vger.kernel.org
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Suggested-by: Jiri Slaby <jslaby@suse.com>
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20200311225736.32147-3-rdunlap@infradead.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12 17:17:30 +01:00
Andy Shevchenko
da9a5aa340 serial: core: Refactor uart_unlock_and_check_sysrq()
Refactor uart_unlock_and_check_sysrq() to:

  - explicitly show that we release a port lock which makes
    static analyzers happy:

CHECK   drivers/tty/serial/serial_core.c
.../serial_core.c:3290:17: warning: context imbalance in 'uart_unlock_and_check_sysrq' - unexpected unlock

  - use flags instead of irqflags to avoid confusion with IRQ flags

  - provide one return point

  - be more compact

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Dmitry Safonov <0x7f454c46@gmail.com>
Link: https://lore.kernel.org/r/20200310174337.74109-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12 17:16:42 +01:00
Andy Shevchenko
e140ef3692 serial: core: Use uart_console() helper in SysRq code
Use uart_console() helper in SysRq code instead of open coded variant.
This eliminates the conditional entirely for SERIAL_CORE_CONSOLE=n case.
While here, refactor the conditional to be more compact.

Reviewed-by: Dmitry Safonov <0x7f454c46@gmail.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200310174337.74109-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12 17:16:41 +01:00
Andy Shevchenko
b18896ff3a serial: core: Print escaped SysRq Magic sequence if enabled
It is useful to see on the serial console the magic sequence itself
to enable SysRq without rummaging source code.

Reviewed-by: Dmitry Safonov <0x7f454c46@gmail.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200310174337.74109-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12 17:16:41 +01:00
Andy Shevchenko
2ce5eace42 serial: core: Use string length for SysRq magic sequence
Compiler is not happy about using ARRAY_SIZE() in comparison to smaller type:

  CC      drivers/tty/serial/serial_core.o
.../serial_core.c: In function ‘uart_try_toggle_sysrq’:
.../serial_core.c:3222:24: warning: comparison is always false due to limited range of data type [-Wtype-limits]
 3222 |  if (++port->sysrq_seq < (ARRAY_SIZE(sysrq_toggle_seq) - 1)) {
      |                        ^

Looking at the code it appears that there is an additional weirdness,
i.e. use ARRAY_SIZE() against simple string literal. Yes, the idea probably
was to allow '\0' in the sequence, but it's impractical: kernel configuration
won't accept it to begin with followed by a comment about '\0' before
comparison in question.

Drop all these by switching to strlen() and convert code accordingly.

Note, GCC seems clever enough to calculate string length at compile time.

Fixes: 68af43173d ("serial/sysrq: Add MAGIC_SYSRQ_SERIAL_SEQUENCE")
Reviewed-by: Dmitry Safonov <0x7f454c46@gmail.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200310174337.74109-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12 17:16:41 +01:00
satya priya
f9d690b6ec tty: serial: qcom_geni_serial: Allocate port->rx_fifo buffer in probe
To fix the RX cancel command failure, rx_fifo buffer needs to be
flushed in stop_rx() by calling handle_rx().In handle_rx() the data
in rx_fifo buffer is read and then dropped, not sent to upper layers.

If set_termios is called before startup, by this time memory is not
allocated to port->rx_fifo buffer, which leads to a NULL pointer
dereference.

To avoid this NULL pointer dereference allocate memory to port->rx_fifo
in probe itself.

Signed-off-by: satya priya <skakit@codeaurora.org>
Reported-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/1583477228-32231-2-git-send-email-skakit@codeaurora.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12 10:10:27 +01:00
Linus Walleij
9a8da6082d tty: serial: ifx6x60: Convert to GPIO descriptors
This driver for the Intel MID never seems to have been properly
integrated upstream: the platform data in <linux/spi/ifx_modem.h>
is not used anywhere in the kernel and haven't been since it was
merged into the kernel in 2010.

There might be out-of-tree users, so I don't want to delete the
driver, but I will refactor it to use GPIO descriptors, which
means that out-of-tree users will need to adapt.

There are several examples in the kernel of how to provide the
resources necessary for using GPIO descriptors to pass in the
GPIO lines, for the MID platform in particular, it will suffice
to inspect the code in files like:
arch/x86/platform/intel-mid/device_libs/platform_bt.c

This refactoring transfers all GPIOs in the driver, including
a hard-coded "PMU reset" in the driver to use GPIO descriptors
instead.

The following named GPIO descriptors need to be supplied:
- reset
- power
- mrdy
- srdy
- rst_out
- pmu_reset

Cc: Russ Gorby <russ.gorby@intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200311083131.693908-2-linus.walleij@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12 10:03:54 +01:00
Linus Walleij
b685e6febd tty: serial: ifx6x60: Use helper variable for dev
The &spi->dev is used so many times that the code gets
visibly better by introducing a simple dev helper variable.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20200311083131.693908-1-linus.walleij@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12 10:03:54 +01:00
Michael Walle
e33253f3b7 tty: serial: fsl_lpuart: add LS1028A earlycon support
Add a early_console_setup() for the LS1028A SoC with 32bit, little
endian access. If the bootloader does a fixup of the clock-frequency
node the baudrate divisor register will automatically be set.

Signed-off-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200306214433.23215-5-michael@walle.cc
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12 10:02:00 +01:00
Michael Walle
c2f448cff2 tty: serial: fsl_lpuart: add LS1028A support
The LS1028A uses little endian register access and has a different FIFO
size encoding.

Signed-off-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200306214433.23215-4-michael@walle.cc
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12 10:02:00 +01:00
Michael Walle
a092ab25fd tty: serial: fsl_lpuart: fix DMA mapping
Use the correct device to request the DMA mapping. Otherwise the IOMMU
doesn't get the mapping and it will generate a page fault.

The error messages look like:
[   19.012140] arm-smmu 5000000.iommu: Unhandled context fault: fsr=0x402, iova=0xbbfff800, fsynr=0x3e0021, cbfrsynra=0x828, cb=9
[   19.023593] arm-smmu 5000000.iommu: Unhandled context fault: fsr=0x402, iova=0xbbfff800, fsynr=0x3e0021, cbfrsynra=0x828, cb=9

This was tested on a custom board with a LS1028A SoC.

Signed-off-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200306214433.23215-3-michael@walle.cc
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12 10:02:00 +01:00
Michael Walle
159381df14 tty: serial: fsl_lpuart: fix DMA operation when using IOMMU
The DMA channel might not be available at probe time. This is esp. the
case if the DMA controller has an IOMMU mapping.

There is also another caveat. If there is no DMA controller at all,
dma_request_chan() will also return -EPROBE_DEFER. Thus we cannot test
for -EPROBE_DEFER in probe(). Otherwise the lpuart driver will fail to
probe if, for example, the DMA driver is not enabled in the kernel
configuration.

To workaround this, we request the DMA channel in _startup(). Other
serial drivers do it the same way.

Signed-off-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200306214433.23215-2-michael@walle.cc
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12 10:02:00 +01:00
Andy Shevchenko
207f6f34fb tty/serial: atmel: Use uart_console() helper
Use uart_console() helper in instead of open coded variant.

Note, SERIAL_CORE_CONSOLE is selected by SERIAL_ATMEL_CONSOLE,
thus no functional changes expected.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Richard Genoud <richard.genoud@gmail.com>
Link: https://lore.kernel.org/r/20200310133057.86840-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12 10:00:22 +01:00
Andy Shevchenko
cfb7bdfc69 serial: pic32_uart: Use uart_console() helper
Use uart_console() helper in instead of open coded variant.

Note, SERIAL_CORE_CONSOLE is selected by SERIAL_PIC32_CONSOLE,
thus no functional changes expected.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200311090027.64441-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12 10:00:22 +01:00
Palmer Dabbelt
4cbd7814bb tty: sifive: Finish transmission before changing the clock
SiFive's UART has a software controller clock divider that produces the
final baud rate clock.  Whenever the clock that drives the UART is
changed this divider must be updated accordingly, and given that these
two events are controlled by software they cannot be done atomically.
During the period between updating the UART's driving clock and internal
divider the UART will transmit a different baud rate than what the user
has configured, which will probably result in a corrupted transmission
stream.

The SiFive UART has a FIFO, but due to an issue with the programming
interface there is no way to directly determine when the UART has
finished transmitting.  We're essentially restricted to dead reckoning
in order to figure that out: we can use the FIFO's TX busy register to
figure out when the last frame has begun transmission and just delay for
a long enough that the last frame is guaranteed to get out.

As far as the actual implementation goes: I've modified the existing
existing clock notifier function to drain both the FIFO and the shift
register in on PRE_RATE_CHANGE.  As far as I know there is no hardware
flow control in this UART, so there's no good way to ask the other end
to stop transmission while we can't receive (inserting software flow
control messages seems like a bad idea here).

Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Tested-by: Yash Shah <yash.shah@sifive.com>
Link: https://lore.kernel.org/r/20200307042637.83728-1-palmer@dabbelt.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-12 09:55:41 +01:00
Greg Kroah-Hartman
cb05c6c82f Merge 5.6-rc5 into tty-next
We need the vt fixes in here and it resolves a merge issue with
drivers/tty/vt/selection.c

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-10 10:02:49 +01:00
Serge Semin
d24e163af0 tty: mips_ejtag_fdc: Mark expected switch fall-through
Mark mips_ejtag_fdc_encode() methods switch-case-4 as expecting to
fall through.

This patch fixes the following warning:

drivers/tty/mips_ejtag_fdc.c: In function ‘mips_ejtag_fdc_encode’:
drivers/tty/mips_ejtag_fdc.c:245:13: warning: this statement may fall through [-Wimplicit-fallthrough=]
   word.word &= 0x00ffffff;
   ~~~~~~~~~~^~~~~~~~~~~~~
drivers/tty/mips_ejtag_fdc.c:246:2: note: here
  case 3:
  ^~~~

Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Signed-off-by: Alexey Malahov <Alexey.Malahov@baikalelectronics.ru>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Link: https://lore.kernel.org/r/20200306124913.151A68030792@mail.baikalelectronics.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-07 09:52:02 +01:00
Dmitry Safonov
68af43173d serial/sysrq: Add MAGIC_SYSRQ_SERIAL_SEQUENCE
Many embedded boards have a disconnected TTL level serial which can
generate some garbage that can lead to spurious false sysrq detects.

Currently, sysrq can be either completely disabled for serial console
or always disabled (with CONFIG_MAGIC_SYSRQ_SERIAL), since
commit 732dbf3a61 ("serial: do not accept sysrq characters via serial port")

At Arista, we have such boards that can generate BREAK and random
garbage. While disabling sysrq for serial console would solve
the problem with spurious false sysrq triggers, it's also desirable
to have a way to enable sysrq back.

As a measure of balance between on and off options, add
MAGIC_SYSRQ_SERIAL_SEQUENCE which is a string sequence that can enable
sysrq if it follows BREAK on a serial line. The longer the string - the
less likely it may be in the garbage.

Having the way to enable sysrq was beneficial to debug lockups with
a manual investigation in field and on the other side preventing false
sysrq detections.

Based-on-patch-by: Vasiliy Khoruzhick <vasilykh@arista.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Link: https://lore.kernel.org/r/20200302175135.269397-3-dima@arista.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-07 09:52:02 +01:00
Dmitry Safonov
eaee41727e sysctl/sysrq: Remove __sysrq_enabled copy
Many embedded boards have a disconnected TTL level serial which can
generate some garbage that can lead to spurious false sysrq detects.

Currently, sysrq can be either completely disabled for serial console
or always disabled (with CONFIG_MAGIC_SYSRQ_SERIAL), since
commit 732dbf3a61 ("serial: do not accept sysrq characters via serial port")

At Arista, we have such boards that can generate BREAK and random
garbage. While disabling sysrq for serial console would solve
the problem with spurious false sysrq triggers, it's also desirable
to have a way to enable sysrq back.

Having the way to enable sysrq was beneficial to debug lockups with
a manual investigation in field and on the other side preventing false
sysrq detections.

As a preparation to add sysrq_toggle_support() call into uart,
remove a private copy of sysrq_enabled from sysctl - it should reflect
the actual status of sysrq.

Furthermore, the private copy isn't correct already in case
sysrq_always_enabled is true. So, remove __sysrq_enabled and use a
getter-helper sysrq_mask() to check sysrq_key_op enabled status.

Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Dmitry Safonov <dima@arista.com>
Link: https://lore.kernel.org/r/20200302175135.269397-2-dima@arista.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-07 09:52:02 +01:00
Lukas Wunner
7f9803072f serial: 8250: Support console on software emulated rs485 ports
Commit e490c9144c ("tty: Add software emulated RS485 support for 8250")
introduced support to use RTS as an rs485 Transmit Enable signal if data
is transmitted through the tty layer.

Console messages bypass the tty layer and instead are emitted via
serial8250_console_write().  Amend that function to drive RTS as well,
allowing for a console on rs485 ports.

Note that serial8250_console_write() may be called concurrently to the
tty layer accessing the port.  The two protect their accesses with the
port lock, but serial8250_console_write() may find RTS still being
asserted by the tty layer, in which case it shouldn't be deasserted
after the console message has been printed.  Recognize such situations
by checking the em485->tx_stopped flag.

If a delay_rts_before_send or delay_rts_after_send has been specified,
serial8250_console_write() busy-waits for its duration.  Optimizations
for those wait times are conceivable:  E.g. if RTS is already asserted,
we could check whether em485->start_tx_timer is active and wait only
for the remaining expire time.  But this would require calling into
the hrtimer infrastructure, which involves acquiring locks and
potentially reprogramming timer hardware.  Such operations seem too
risky in the context of console printout, which needs to work even when
the kernel has crashed and emits a BUG splat.  So I've gone with a
simplistic solution which just always waits for the full delay.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Matwey V. Kornilov <matwey@sai.msu.ru>
Link: https://lore.kernel.org/r/65edffce4670a19e598015c03cbe46f1ffd93e43.1582895077.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-07 09:52:02 +01:00
Lukas Wunner
f93bf75891 serial: 8250_bcm2835aux: Support rs485 software emulation
Amend 8250_bcm2835aux.c to support rs485 as introduced for 8250_omap.c
by commit e490c9144c ("tty: Add software emulated RS485 support for
8250").

The bcm2835aux differs from omap chips by inverting the meaning of RTS
in the MCR register:  If the bit is clear, RTS is high.  With omap, it's
apparently the other way round.

Moreover, omap achieves half-duplex mode by disabling the UART_IER_RDI
interrupt and clearing the RX FIFO when TX stops.  This approach doesn't
work on bcm2835aux because the UART_LSR_DR bit is set even when
UART_IER_RDI is disabled.  Consequently, serial8250_handle_irq() invokes
serial8250_rx_chars() to empty the FIFO and characters are received even
though the user requested half-duplex.  Solve by disabling the receiver
using the non-standard CNTL register.

Cache that register in the driver's private data for performance.  Set
the private data pointer before calling serial8250_register_8250_port()
to prevent a null pointer deref in case one of the rs485 callbacks is
invoked immediately after port registration.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Matwey V. Kornilov <matwey@sai.msu.ru>
Link: https://lore.kernel.org/r/dd86460e20a8f979b7272a0bde73640312b902b1.1582895077.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-07 09:52:02 +01:00
Lukas Wunner
058bc104f7 serial: 8250: Generalize rs485 software emulation
Commit e490c9144c ("tty: Add software emulated RS485 support for 8250")
introduced support to use RTS as an rs485 Transmit Enable signal.
So far the only drivers taking advantage of it are 8250_omap.c and
8250_of.c.

We're about to make use of the feature in 8250_bcm2835aux.c as well.
The bcm2835aux differs from omap chips by inverting the meaning of RTS
in the MCR register.  Moreover, omap achieves half-duplex mode by
disabling the RX interrupt and clearing the RX FIFO when TX stops.
The bcm2835aux requires disabling the receiver instead.

Support these behavioral differences by generalizing the rs485 emulation:
Introduce ->rs485_start_tx() and ->rs485_stop_tx() callbacks in struct
uart_8250_port, provide generic implementations containing the existing
code and use them as callbacks in 8250_omap.c and 8250_of.c.

start_tx_rs485() is idempotent in that it recognizes whether RTS is
already asserted.  Achieve the same by introducing a tx_stopped flag in
struct uart_8250_em485.  This may even perform a little better on arches
where memory access is faster than mmio access.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Matwey V. Kornilov <matwey@sai.msu.ru>
Link: https://lore.kernel.org/r/5ac0464ae4414708e723a1e0d52b0c1b2bd41b9b.1582895077.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-07 09:52:02 +01:00
Lukas Wunner
41a70b7f47 serial: 8250: Deduplicate rs485 active_timer assignment
When rs485 transmission over an 8250 port stops, __stop_tx() assigns
active_timer = NULL before calling __stop_tx_rs485().

That function in turn either assigns active_timer = stop_tx_timer and
rearms the timer (in case a delay_rts_after_send needs to be observed)
or directly calls __do_stop_tx_rs485().

Move the assignment active_timer = NULL to __stop_tx_rs485() into the
branch which directly calls __do_stop_tx_rs485(), thereby avoiding a
duplicate assignment and simplifying the code.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Matwey V. Kornilov <matwey@sai.msu.ru>
Link: https://lore.kernel.org/r/bca638405550eaf92f0c6060b553b687f35885e0.1582895077.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-07 09:52:02 +01:00
Lukas Wunner
6d3e54e195 serial: 8250: Sanitize rs485 config harder
Amend the generic ->rs485_config() callback to sanitize RTS polarity and
zero-fill the padding (in addition to the existing sanitization of the
RTS delays).

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Matwey V. Kornilov <matwey@sai.msu.ru>
Link: https://lore.kernel.org/r/ff833721bc372d38678f289eb2a44dbf016d5203.1582895077.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-07 09:52:01 +01:00
Lukas Wunner
283e096ffb serial: 8250: Deduplicate ->rs485_config() callback
Commit e490c9144c ("tty: Add software emulated RS485 support for 8250")
introduced support to use RTS as an rs485 Transmit Enable signal.
Drivers opt in to the feature by calling serial8250_em485_init() from
their ->rs485_config() callback.

So far there are two drivers doing that, 8250_omap.c and 8250_of.c.
Both use an identical callback.  We're about to add a third user of that
callback, therefore deduplicate it and move it to 8250_port.c.

Drivers now opt in to rs485 software emulation by assigning the generic
serial8250_rs485_config() callback introduced herein to their
.rs485_config struct member.  This change allows unexporting
serial8250_em485_init() and declaring it static.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Matwey V. Kornilov <matwey@sai.msu.ru>
Cc: Heiko Schocher <hs@denx.de>
Link: https://lore.kernel.org/r/fcef63642dc4eae41ae7842d23747b2bf5d40285.1582895077.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-07 09:52:01 +01:00
Lukas Wunner
fe7f0fa43c serial: 8250: Support rs485 devicetree properties
Retrieve rs485 devicetree properties on registration of 8250 ports in
case they are attached to an rs485 transceiver.

If the property "linux,rs485-enabled-at-boot-time" is present, invoke
the ->rs485_config() callback to immediately deassert RTS, thereby
ceasing control of the bus.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Giulio Benetti <giulio.benetti@micronovasrl.com>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/5908ea89b7f9da54872d6634b606d83db032297a.1582895077.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-07 09:52:01 +01:00
Lukas Wunner
f45709df77 serial: 8250: Don't touch RTS modem control while in rs485 mode
serial8250_do_set_mctrl() currently allows modifying the RTS modem
control line even when RTS is used as an rs485 Transmit Enable signal.
It is thus possible for user space to interfere with rs485 communication
by invoking a TIOCMSET ioctl().

Ignore such change requests and retain the current RTS polarity when in
rs485 mode.  Note that serial8250_set_mctrl() is always called with
port->lock held, so there's no risk that RTS is changed concurrently.

Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: Matwey V. Kornilov <matwey@sai.msu.ru>
Link: https://lore.kernel.org/r/b1ce34ca9bc4d7bdc6e9852fcf30b1f4e37c8a80.1582895077.git.lukas@wunner.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-07 09:52:01 +01:00
Michael Walle
f8c3686c65 serial: earlycon: prefer EARLYCON_DECLARE() variant
If a driver exposes early consoles with EARLYCON_DECLARE() and
OF_EARLYCON_DECLARE(), pefer the non-OF variant if the user specifies it
by
  earlycon=<driver>,<options>

The rationale behind this is that some drivers register multiple setup
functions under the same driver name. Eg.

OF_EARLYCON_DECLARE(lpuart, "fsl,vf610-lpuart", lpuart_early_console_setup);
OF_EARLYCON_DECLARE(lpuart32, "fsl,ls1021a-lpuart", lpuart32_early_console_setup);
OF_EARLYCON_DECLARE(lpuart32, "fsl,imx7ulp-lpuart", lpuart32_imx_early_console_setup);
EARLYCON_DECLARE(lpuart, lpuart_early_console_setup);
EARLYCON_DECLARE(lpuart32, lpuart32_early_console_setup);

It depends on the order of the entries which console_setup() actually
gets called. To make things worse, I guess it also depends on the
compiler how these are ordered. Thus always prefer the EARLYCON_DECLARE()
ones.

Signed-off-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200220174607.24285-1-michael@walle.cc
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-07 09:52:01 +01:00
Nishad Kamdar
4f5f588737 tty: serial: Use the correct style for SPDX License Identifier
This patch corrects the SPDX License Identifier style in
header files related to tty serial drivers.
For C header files Documentation/process/license-rules.rst
mandates C-like comments (opposed to C source files where
C++ style should be used).

Changes made by using a script provided by Joe Perches here:
https://lkml.org/lkml/2019/2/7/46.

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Nishad Kamdar <nishadkamdar@gmail.com>
Link: https://lore.kernel.org/r/20200301204517.GA10368@nishad
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-07 09:52:01 +01:00
Michael Walle
2b2e71fe65 tty: serial: fsl_lpuart: free IDs allocated by IDA
Since commit 3bc3206e1c ("serial: fsl_lpuart: Remove the alias node
dependence") the port line number can also be allocated by IDA, but in
case of an error the ID will no be removed again. More importantly, any
ID will be freed in remove(), even if it wasn't allocated but instead
fetched by of_alias_get_id(). If it was not allocated by IDA there will
be a warning:
  WARN(1, "ida_free called for id=%d which is not allocated.\n", id);

Move the ID allocation more to the end of the probe() so that we still
can use plain return in the first error cases.

Fixes: 3bc3206e1c ("serial: fsl_lpuart: Remove the alias node dependence")
Signed-off-by: Michael Walle <michael@walle.cc>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200303174306.6015-3-michael@walle.cc
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-06 14:10:44 +01:00
Michael Walle
0e28ed6c9d Revert "tty: serial: fsl_lpuart: drop EARLYCON_DECLARE"
This reverts commit a659652f61.

This broke the earlycon on LS1021A processors because the order of the
earlycon_setup() functions were changed. Before the commit the normal
lpuart32_early_console_setup() was called. After the commit the
lpuart32_imx_early_console_setup() is called instead.

Fixes: a659652f61 ("tty: serial: fsl_lpuart: drop EARLYCON_DECLARE")
Signed-off-by: Michael Walle <michael@walle.cc>
Link: https://lore.kernel.org/r/20200303174306.6015-2-michael@walle.cc
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-06 14:10:44 +01:00
Ronald Tschalär
35d4670aae serdev: Fix detection of UART devices on Apple machines.
On Apple devices the _CRS method returns an empty resource template, and
the resource settings are instead provided by the _DSM method. But
commit 33364d63c7 (serdev: Add ACPI
devices by ResourceSource field) changed the search for serdev devices
to require valid, non-empty resource template, thereby breaking Apple
devices and causing bluetooth devices to not be found.

This expands the check so that if we don't find a valid template, and
we're on an Apple machine, then just check for the device being an
immediate child of the controller and having a "baud" property.

Cc: <stable@vger.kernel.org> # 5.5
Fixes: 33364d63c7 ("serdev: Add ACPI devices by ResourceSource field")
Signed-off-by: Ronald Tschalär <ronald@innovation.ch>
Link: https://lore.kernel.org/r/20200211194723.486217-1-ronald@innovation.ch
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-06 14:10:44 +01:00
Chunyan Zhang
7ba87cfec7 tty: serial: make SERIAL_SPRD not depend on ARCH_SPRD
Remove the dependency with ARCH_SPRD from sprd serial/console Kconfig-s,
since we want them can be built-in when ARCH_SPRD is set as 'm'.

Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com>
Link: https://lore.kernel.org/r/20200305103228.9686-2-zhang.lyra@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-06 13:31:20 +01:00
Andy Shevchenko
1b91d97c66 serial: 8250_lpss: Add ->setup() for Elkhart Lake ports
The ->setup() callback is mandatory for the devices.
Provide it for Elkhart Lake UART ports.

Note, for time being it's empty, but in the future it might require
an additional configuration such as DMA.

Reported-by: Raymond Tan <raymond.tan@intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200305130822.36850-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-06 13:31:19 +01:00
Changqi Hu
e32a83c70c serial: 8250-mtk: modify mtk uart power and clock management
MTK uart design no need to control uart clock,
so we just control bus clock in runtime function.
Add uart clock used count to avoid repeatedly switching the clock.

Signed-off-by: Changqi Hu <changqi.hu@mediatek.com>
Link: https://lore.kernel.org/r/1582707225-26815-1-git-send-email-changqi.hu@mediatek.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-06 13:28:30 +01:00
George Hilliard
5a08a4877a tty: imx serial: Implement support for reversing TX and RX polarity
The peripheral has support for inverting its input and/or output
signals.  This is useful if the hardware flips polarity of the
peripheral's signal, such as swapped +/- pins on an RS-422 transceiver,
or an inverting level shifter.  Add support for these control registers
via the device tree binding.

As part of this change, make the writes of the various registers more
uniform by moving the UCR3 block up near the other registers' blocks,
since the INVT bit must be set before enabling the peripheral.

Signed-off-by: George Hilliard <ghilliard@kopismobile.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20200226222319.18383-3-ghilliard@kopismobile.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-06 13:26:26 +01:00
Daniel Golle
9be1064fe5 serial: ar933x_uart: add RS485 support
Emulate half-duplex operation and use mctrl_gpio to add support for
RS485 tranceiver with transmit/receive switch hooked to RTS GPIO line.
This is needed to make use of the RS485 port found on Teltonika RUT955.

Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Link: https://lore.kernel.org/r/20200221212331.GA21467@makrotopia.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-06 13:26:26 +01:00
Roja Rani Yarubandi
9fa3c4b1fa tty: serial: qcom_geni_serial: Fix GPIO swapping with workaround
Add capability to support RX-TX, CTS-RTS pins swap in HW.

Configure UART_IO_MACRO_CTRL register accordingly if RX-TX pair
or CTS-RTS pair or both pairs swapped.

Signed-off-by: Roja Rani Yarubandi <rojay@codeaurora.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Tested-by: Matthias Kaehlcke <mka@chromium.org>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Link: https://lore.kernel.org/r/20200304112203.408-1-rojay@codeaurora.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-06 13:16:20 +01:00
Linus Walleij
97cbaf2c82 tty: serial: cpm_uart: Convert to use GPIO descriptors
The CPM UART (PowerPC) has an open coded GPIO modem control
handling. Since I can't test this I can't just migrate it to
the serial mctrl GPIO helper library though I wish I could.
I do second best and convert it to GPIO descriptors at least.

Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20200229231842.247563-1-linus.walleij@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-06 13:16:16 +01:00
Linus Walleij
8145e85f82 tty: serial: lantiq: Drop GPIO include
Nothing in this driver uses the symbols from <linux/gpio.h>
so drop this include.

Cc: Rahul Tanwar <rahul.tanwar@linux.intel.com>
Cc: Songjun Wu <songjun.wu@linux.intel.com>
Cc: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Cc: John Crispin <john@phrozen.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20200229212331.174946-1-linus.walleij@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-06 13:16:16 +01:00
Linus Walleij
67f468d4ae tty: serial: atmel_serial: Drop GPIO includes
Nothing in this driver uses the symbols from these GPIO
includes so drop them. These are probably just historical
artifacts from befor mctrl_gpio was used.

Cc: Ludovic Desroches <ludovic.desroches@microchip.com>
Cc: Razvan Stefanescu <razvan.stefanescu@microchip.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Link: https://lore.kernel.org/r/20200229220941.205599-1-linus.walleij@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-06 13:16:16 +01:00
Jiri Slaby
bc80932cc2 vt: selection, indent switch-case properly
Shift the cases one level left as this is how we are supposed to write
the switch-case code according to the CodingStyle.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219073951.16151-9-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-06 08:35:40 +01:00
Jiri Slaby
6ff66e0813 vt: selection, remove redeclaration of poke_blanked_console
It is declared in vt_kern.h, so no need to declare it in selection.c
which includes the header.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219073951.16151-8-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-06 08:35:40 +01:00
Jiri Slaby
f400991bf8 vt: switch vt_dont_switch to bool
vt_dont_switch is pure boolean, no need for whole char.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219073951.16151-6-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-06 08:35:39 +01:00
Jiri Slaby
9256d09f1d vt: selection, create struct from console selection globals
Move all the selection global variables to a structure vc_selection,
instantiated as vc_sel. This helps to group all the variables together
and see what should be protected by the embedded lock too.

It might be used later also for per-console selection support.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219073951.16151-5-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-06 08:35:39 +01:00
Jiri Slaby
555b4ef797 vt: selection, localize use_unicode
use_unicode needs not be global. It is used only in set_selection_kernel
and sel_pos (a callee). It is also always set there prior calling
sel_pos. So make use_unicode local and rename it to plain shorter
"unicode". Finally, propagate it to sel_pos via parameter.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219073951.16151-4-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-06 08:35:38 +01:00
Jiri Slaby
101f227c24 vt: selection, remove 2 local variables from set_selection_kernel
multiplier and mode are not actually needed:
* multiplier is used only in kmalloc_array, so use "use_unicode ? 4 : 1"
  directly
* mode is used only to assign a bool in this manner:
  if (cond)
    x = true;
  else
    x = false;
  So do "x = cond" directly.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219073951.16151-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-06 08:35:38 +01:00
Jay Dolan
10c5ccc3c6 serial: 8250_exar: add support for ACCES cards
Add ACCES VIDs and PIDs that use the Exar chips

Signed-off-by: Jay Dolan <jay.dolan@accesio.com>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200305140504.22237-1-jay.dolan@accesio.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-05 21:30:04 +01:00
tangbin
4a3e208474 tty:serial:mvebu-uart:fix a wrong return
in this place, the function should return a
negative value and the PTR_ERR already returns
a negative,so return -PTR_ERR() is wrong.

Signed-off-by: tangbin <tangbin@cmss.chinamobile.com>
Cc: stable <stable@vger.kernel.org>
Acked-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200305013823.20976-1-tangbin@cmss.chinamobile.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-03-05 21:26:34 +01:00
Jiri Slaby
e8c75a30a2 vt: selection, push sel_lock up
sel_lock cannot nest in the console lock. Thanks to syzkaller, the
kernel states firmly:

> WARNING: possible circular locking dependency detected
> 5.6.0-rc3-syzkaller #0 Not tainted
> ------------------------------------------------------
> syz-executor.4/20336 is trying to acquire lock:
> ffff8880a2e952a0 (&tty->termios_rwsem){++++}, at: tty_unthrottle+0x22/0x100 drivers/tty/tty_ioctl.c:136
>
> but task is already holding lock:
> ffffffff89462e70 (sel_lock){+.+.}, at: paste_selection+0x118/0x470 drivers/tty/vt/selection.c:374
>
> which lock already depends on the new lock.
>
> the existing dependency chain (in reverse order) is:
>
> -> #2 (sel_lock){+.+.}:
>        mutex_lock_nested+0x1b/0x30 kernel/locking/mutex.c:1118
>        set_selection_kernel+0x3b8/0x18a0 drivers/tty/vt/selection.c:217
>        set_selection_user+0x63/0x80 drivers/tty/vt/selection.c:181
>        tioclinux+0x103/0x530 drivers/tty/vt/vt.c:3050
>        vt_ioctl+0x3f1/0x3a30 drivers/tty/vt/vt_ioctl.c:364

This is ioctl(TIOCL_SETSEL).
Locks held on the path: console_lock -> sel_lock

> -> #1 (console_lock){+.+.}:
>        console_lock+0x46/0x70 kernel/printk/printk.c:2289
>        con_flush_chars+0x50/0x650 drivers/tty/vt/vt.c:3223
>        n_tty_write+0xeae/0x1200 drivers/tty/n_tty.c:2350
>        do_tty_write drivers/tty/tty_io.c:962 [inline]
>        tty_write+0x5a1/0x950 drivers/tty/tty_io.c:1046

This is write().
Locks held on the path: termios_rwsem -> console_lock

> -> #0 (&tty->termios_rwsem){++++}:
>        down_write+0x57/0x140 kernel/locking/rwsem.c:1534
>        tty_unthrottle+0x22/0x100 drivers/tty/tty_ioctl.c:136
>        mkiss_receive_buf+0x12aa/0x1340 drivers/net/hamradio/mkiss.c:902
>        tty_ldisc_receive_buf+0x12f/0x170 drivers/tty/tty_buffer.c:465
>        paste_selection+0x346/0x470 drivers/tty/vt/selection.c:389
>        tioclinux+0x121/0x530 drivers/tty/vt/vt.c:3055
>        vt_ioctl+0x3f1/0x3a30 drivers/tty/vt/vt_ioctl.c:364

This is ioctl(TIOCL_PASTESEL).
Locks held on the path: sel_lock -> termios_rwsem

> other info that might help us debug this:
>
> Chain exists of:
>   &tty->termios_rwsem --> console_lock --> sel_lock

Clearly. From the above, we have:
 console_lock -> sel_lock
 sel_lock -> termios_rwsem
 termios_rwsem -> console_lock

Fix this by reversing the console_lock -> sel_lock dependency in
ioctl(TIOCL_SETSEL). First, lock sel_lock, then console_lock.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Reported-by: syzbot+26183d9746e62da329b8@syzkaller.appspotmail.com
Fixes: 07e6124a1a ("vt: selection, close sel_buffer race")
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200228115406.5735-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 16:06:49 +01:00
Jiri Slaby
4b70dd57a1 vt: selection, push console lock down
We need to nest the console lock in sel_lock, so we have to push it down
a bit. Fortunately, the callers of set_selection_* just lock the console
lock around the function call. So moving it down is easy.

In the next patch, we switch the order.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Fixes: 07e6124a1a ("vt: selection, close sel_buffer race")
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200228115406.5735-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-28 16:06:49 +01:00
Greg Kroah-Hartman
ba08cf452f Merge 5.6-rc3 into tty-next
We want the tty fixes in here as well.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-24 08:39:55 +01:00
Kees Cook
e24cd4e6d6 n_tty: Distribute switch variables for initialization
Variables declared in a switch statement before any case statements
cannot be automatically initialized with compiler instrumentation (as
they are not part of any execution flow). With GCC's proposed automatic
stack variable initialization feature, this triggers a warning (and they
don't get initialized). Clang's automatic stack variable initialization
(via CONFIG_INIT_STACK_ALL=y) doesn't throw a warning, but it also
doesn't initialize such variables[1]. Note that these warnings (or silent
skipping) happen before the dead-store elimination optimization phase,
so even when the automatic initializations are later elided in favor of
direct initializations, the warnings remain.

To avoid these problems, move such variables into the "case" where
they're used or lift them up into the main function body.

drivers/tty/n_tty.c: In function ‘__process_echoes’:
drivers/tty/n_tty.c:657:18: warning: statement will never be executed [-Wswitch-unreachable]
  657 |     unsigned int num_chars, num_bs;
      |                  ^~~~~~~~~

[1] https://bugs.llvm.org/show_bug.cgi?id=44916

Reviewed-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20200220062313.69209-1-keescook@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-23 20:14:50 +01:00
Jiri Slaby
e587e8f174 vt: ioctl, switch VT_IS_IN_USE and VT_BUSY to inlines
These two were macros. Switch them to static inlines, so that it's more
understandable what they are doing.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219073951.16151-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-21 10:31:18 +01:00
Jiri Slaby
dce05aa6ee vt: selection, introduce vc_is_sel
Avoid global variables (namely sel_cons) by introducing vc_is_sel. It
checks whether the parameter is the current selection console. This will
help putting sel_cons to a struct later.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219073951.16151-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-21 10:31:18 +01:00
Jiri Slaby
80967ff2d1 n_hdlc: wrap a comment properly
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084118.26491-24-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-21 10:24:34 +01:00
Jiri Slaby
1283c72135 n_hdlc: fix whitespace around binary operators
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084118.26491-23-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-21 10:24:34 +01:00
Jiri Slaby
8d79bb5c4b n_hdlc: add missing spaces after commas
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084118.26491-22-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-21 10:24:34 +01:00
Jiri Slaby
2bfb2b753b n_hdlc: remove spaces between function name and (
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084118.26491-21-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-21 10:24:34 +01:00
Jiri Slaby
43741e9bc0 n_hdlc: remove useless whitespace at line wraps
Do
  s@[ \t]\+$@@
  s@ \+\t@\t@
on the file as there are many spaces at the begininning of lines and
many spaces/tabs at EOLs. And vim screamed.

git show -w is supposed to show no difference here.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084118.26491-20-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-21 10:24:34 +01:00
Jiri Slaby
d86b05cb0e n_hdlc: use __func__ and pr_ print helpers
* we mark the message in n_hdlc_tty_receive as error
* we use __func__ instead of explicit function name
* we switch the remaining prints to pr_* helpers

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084118.26491-19-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-21 10:24:34 +01:00
Jiri Slaby
b9c010dfe8 n_hdlc: remove unneeded ifdef
TTY_NO_WRITE_SPLIT is (always) defined in linux/tty.h, so no need to
check for it.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084118.26491-18-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-21 10:24:34 +01:00
Jiri Slaby
0f23829814 n_hdlc: switch tbusy and woke_up to bools
They are in fact bools, so save some bytes (8B on x86_64). Also describe
@woke_up as we know what it is.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084118.26491-17-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-21 10:24:33 +01:00
Jiri Slaby
edee649f9d n_hdlc: move tty_ldisc_ops to the bottom
This makes forward declarations unnecessary. So drop them.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084118.26491-16-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-21 10:24:33 +01:00
Jiri Slaby
740708abbb n_hdlc: add helper for buffers allocation
Given both rx and tx allocations do the same, add a new helper
(n_hdlc_alloc_buf) and use it for both of them. This cleans up
n_hdlc_alloc slightly.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084118.26491-15-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-21 10:24:33 +01:00
Jiri Slaby
844cc5f9e5 n_hdlc: remove checking of n_hdlc
We got rid of backup_tty recently. Also, the tty layer ensures not to
call other ldisc hooks after ldisc close. That means, all those tests
are superfluous now so remove them.

Note that we remove the magic check in write after schedule too. The tty
cannot change during schedule.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084118.26491-14-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-21 10:24:33 +01:00
Jiri Slaby
df6de639d4 n_hdlc: remove cached tty
It's not needed, as now it's clear, that it's always the same as the one
passed from the tty layer.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084118.26491-13-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-21 10:24:33 +01:00
Jiri Slaby
43e784eca8 n_hdlc: inline n_hdlc_release
Put the body of n_hdlc_release into the only caller. It can be seen,
that the "if" is superfluous now -- the same happens few lines above in
n_hdlc_tty_close already. So drop it.

Drop also n_hdlc2tty macro as this was the only user.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084118.26491-12-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-21 10:24:33 +01:00
Jiri Slaby
75011682e7 n_hdlc: expand tty2n_hdlc macro
It's simple tty->disc_data, but it obfuscates code. So expand it to all
locations and drop it.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084118.26491-11-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-21 10:24:33 +01:00
Jiri Slaby
4040c82860 n_hdlc: remove unused backup_tty
It's only set to NULL and never properly used.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084118.26491-10-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-21 10:24:33 +01:00
Jiri Slaby
a1274b26ac n_hdlc: remove unused flags
They are only set to 0 and never read.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084118.26491-9-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-21 10:24:33 +01:00
Jiri Slaby
5f2895143d n_hdlc: invert conditions in n_hdlc_tty_close and n_hdlc_tty_poll
This makes the functions return immediatelly on invalid state. And we
can push the indent of the later code one level left.

Pass "-w" to "git show" to see we are changing only the conditions (and
whitespace).

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084118.26491-8-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-21 10:24:33 +01:00
Jiri Slaby
30fafd92c2 n_hdlc: simplify freeing of buffer list
n_hdlc_release contains four loops to free each buffer list. Create a
helper (n_hdlc_free_buf_list) and call it for every list instead. It
makes n_hdlc_release more readable.

We are switching from "for (;;)" to "do {} while (buf)" which avoids the
"if (buf)" completely -- kfree is a nop for NULL pointers.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084118.26491-7-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-21 10:24:33 +01:00
Jiri Slaby
c549725ff8 n_hdlc: use clamp() for maxframe
It is easier to read. And use MAX_HDLC_FRAME_SIZE instead of magic
constant.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084118.26491-6-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-21 10:24:32 +01:00
Jiri Slaby
cda3756ca5 n_hdlc: cleanup messages during registration
1) n_hdlc prints two lines during registration. Squeeze it into one.
2) prefix the error message with "N_HDLC: ", so that it's clear which
   ldisc failed to register.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084118.26491-5-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-21 10:24:32 +01:00
Jiri Slaby
aebe5fc3b5 n_hdlc: put init/exit strings directly to prints
These strings were put aside from prints to save some bytes after module
load or when built-in -- they were freed after module load (__init ones) or
when the driver is selected as built-in (__exit ones).

The savings are negligible, but the code readability is worse by the
order of magnitude. So put the strings where they belong. Note that it
also used to make little sense putting const data in .data (the __exit
case).

While at it, switch to pr_info, pr_err, not using the KERN_INFO and _ERR
directly.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084118.26491-4-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-21 10:24:32 +01:00
Jiri Slaby
f3c2e27750 n_hdlc: convert debuglevel use to pr_debug
With pr_debug we have a fine-grained control about debugging prints. So
convert the use of global debuglevel variable and tests to a commonly
used pr_debug. And drop debuglevel completely.

This also implicitly adds a loglevel to the messages (KERN_DEBUG) as it
was missing on most of them.

And also use __func__ instead of function names explicitly typed.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084118.26491-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-21 10:24:32 +01:00
Jiri Slaby
683efabc66 n_hdlc: remove unused macros
VERSION and bset are unused. Remove them.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084118.26491-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-21 10:24:32 +01:00
Jiri Slaby
66c3bdf11d n_hdlc: remove tracing debug prints
We can trace functions using ftrace, so there is no need for this
additional prints. Remove them.

We keep only those which print some additional info, not only function
name & "entry"/"exit".

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084118.26491-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-21 10:24:32 +01:00
Greg Kroah-Hartman
3b3845bb6c tty: serial: samsung_tty: remove SERIAL_SAMSUNG_DEBUG
Since a05025d0ce ("tty: serial: samsung_tty: use standard debugging
macros") this configuration option is not used at all, so remove it from
the Kconfig file.

Cc: linux-kernel@vger.kernel.org
Cc: linux-serial@vger.kernel.org
Cc: linux-samsung-soc@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Shinbeom Choi <sbeom.choi@samsung.com>
Cc: HYUN-KI KOO <hyunki00.koo@samsung.com>
Cc: Hyunki Koo <kkoos00@naver.com>
Cc: Donghoon Yu <hoony.yu@samsung.com>
Cc: Kukjin Kim <kgene@kernel.org>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20200220102628.3371996-2-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-20 13:46:28 +01:00
Greg Kroah-Hartman
175b558d0e tty: serial: samsung_tty: build it for any platform
There is no need to tie this driver to only a specific SoC, or compile
test, so remove that dependancy from the Kconfig rules.

Cc: linux-kernel@vger.kernel.org
Cc: linux-serial@vger.kernel.org
Cc: linux-samsung-soc@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Shinbeom Choi <sbeom.choi@samsung.com>
Cc: HYUN-KI KOO <hyunki00.koo@samsung.com>
Cc: Hyunki Koo <kkoos00@naver.com>
Cc: Donghoon Yu <hoony.yu@samsung.com>
Cc: Kukjin Kim <kgene@kernel.org>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20200220102628.3371996-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-20 13:46:19 +01:00
Jiri Slaby
c50704bdef n_gsm: switch escape to bool
gsm_mux->escape is used as a bool, so treat it as such.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084949.28074-10-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-19 12:46:48 +01:00
Jiri Slaby
7a9ed9c069 n_gsm: switch constipated to bool
Both gsm_dlci->constipated and gsm_mux->constipated are used as bools,
so treat them as such.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084949.28074-9-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-19 12:46:48 +01:00
Jiri Slaby
e9360b9a0d n_gsm: switch throttled to bool
gsm_dlci->throttled is used as a bool, so treat it as such.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084949.28074-8-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-19 12:46:48 +01:00
Jiri Slaby
5677fcf376 n_gsm: switch dead to bool
Both gsm_dlci->dead and gsm_mux->dead are used as bools, so treat them
as such.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084949.28074-7-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-19 12:46:48 +01:00
Jiri Slaby
d8ca4ecf8d n_gsm: add missing \n to prints
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084949.28074-6-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-19 12:46:48 +01:00
Jiri Slaby
edd05a735a n_gsm: add missing __user annotations
sparse warns about incorrect types:
n_gsm.c:2638:35: warning: incorrect type in argument 1 (different address spaces)
n_gsm.c:2638:35:    expected void [noderef] <asn:1> *to
n_gsm.c:2638:35:    got void *

The ioctl handler casts its `arg' to (void *) without __user. Add that.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084949.28074-5-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-19 12:46:47 +01:00
Jiri Slaby
329aa6e6e1 n_gsm: introduce enum gsm_mux_state
gsm_mux->state is clearly an enumeration. So introduce one and use it
-- compiler now checks if valid values are assigned to the field.

Note that a compiler warns about unhandled cases in switch. Add default
cases with a pr_debug (which is not printed by default).

The values of the states are preserved thanks to the nature of enum.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084949.28074-4-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-19 12:46:47 +01:00
Jiri Slaby
e1785996f4 n_gsm: introduce enum gsm_dlci_mode
gsm_dlci->mode is clearly an enumeration. So introduce one and use it
-- compiler now checks if valid values are assigned to the field.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084949.28074-3-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-19 12:46:47 +01:00
Jiri Slaby
72ae8cc192 n_gsm: introduce enum gsm_dlci_state
gsm_dlci->state is clearly an enumeration. So introduce one and use it
-- compiler now checks if valid values are assigned to the field.

Note that a compiler warns about unhandled cases in switch. Add default
cases with a pr_debug (which is not printed by default).

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084949.28074-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-19 12:46:47 +01:00
Jiri Slaby
036bca1fcc n_gsm: drop unneeded gsm_dlci->fifo field
gsm_dlci->fifo always points to gsm_dlci->_fifo. So drop the pointer and
rename _fifo to fifo. And update all the users (add & to them).

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200219084949.28074-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-19 12:46:47 +01:00
Andy Shevchenko
21680a6dcb serial: 8250_port: Use dev_*() instead of pr_*()
Convert pr_*() calls to dev_*() ones. We have a port, we should use it.

Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200217114016.49856-5-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-19 11:38:58 +01:00
Andy Shevchenko
567a0e17f7 serial: 8250_port: Switch to use DEVICE_ATTR_RW()
Move device attributes to DEVICE_ATTR_RW() as that would make things
a lot more "obvious" what is happening here.

Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200217114016.49856-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-19 11:38:58 +01:00
Alexandre Belloni
47eff47cc2 tty: serial: efm32: fix spelling mistake "reserverd" -> "reserved"
Fix a spelling mistake in a comment.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20200214141406.20792-1-alexandre.belloni@bootlin.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-02-19 11:38:58 +01:00