Make the slave support depend on CONFIG_I2C_SLAVE. Otherwise it gets
included unconditionally, even when it is not needed.
I2C bus drivers which implement slave support must select
I2C_SLAVE.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Pull i2c updates from Wolfram Sang:
"For 3.19, the I2C subsystem has to offer special candy this time.
Right in time for Christmas :)
- I2C slave framework: finally, a generic mechanism for Linux being
an I2C slave (if the bus driver supports that). Docs are still
missing but will come later this cycle, the code is good enough to
go.
- I2C muxes represent their topology in sysfs much more detailed.
This will help users to navigate around much easier.
- irq population of i2c clients is now done at probe time, not device
creation time, to have better support for deferred probing.
- new drivers for Imagination SCB, Amlogic Meson
- DMA support added for Freescale IMX, Renesas SHMobile
- slightly bigger driver updates to OMAP, i801, AT91, and rk3x
(mostly quirk handling, timing updates, and using better kernel
interfaces)
- eeprom driver can now write with byte-access (very slow, but OK to
have)
- and the bunch of smaller fixes, cleanups, ID updates..."
* 'i2c/for-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (56 commits)
i2c: sh_mobile: remove unneeded DMA mask
i2c: rcar: add slave support
i2c: slave-eeprom: add eeprom simulator driver
i2c: core changes for slave support
MAINTAINERS: add I2C dt bindings also to I2C realm
i2c: designware: Fix falling time bindings doc
i2c: davinci: switch to use platform_get_irq
Documentation: i2c: Use PM ops instead of legacy suspend/resume
i2c: sh_mobile: optimize irq entry
i2c: pxa: add support for SCCB devices
omap: i2c: don't check bus state IP rev3.3 and earlier
i2c: s3c2410: Handle i2c sys_cfg register in i2c driver
i2c: rk3x: add Kconfig dependency on COMMON_CLK
i2c: omap: add notes related to i2c multimaster mode
i2c: omap: don't reset controller if Arbitration Lost detected
i2c: omap: implement workaround for handling invalid BB-bit values
i2c: omap: cleanup register definitions
i2c: rk3x: handle dynamic clock rate changes correctly
i2c: at91: enable probe deferring on dma channel request
i2c: at91: remove legacy DMA support
...
Finally(!), make Linux support being an I2C slave. Most of the existing
infrastructure is reused. We mainly add i2c_slave_register/unregister()
calls which tells i2c bus drivers to activate the slave mode. Then, they
also get a callback to report slave events to.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Lots of activity in the devicetree code for v3.18. Most of it is related
to getting all of the overlay support code in place, but there are other
important things in there.
There are a few trivial merge conflicts. They shouldn't give you any
trouble.
Highlights:
- OF_RECONFIG notifiers for SPI, I2C and Platform devices. Those
subsystems can now respond to live changes to the device tree.
- CONFIG_OF_OVERLAY method for applying live changes to the device tree
- Removal of the of_allnodes list. This used to be used to iterate over
all the nodes in the device tree, but it is unnecessary because the
same thing can be done by iterating over the list of child pointers.
Getting rid of of_allnodes saves some memory and avoids the
possibility of of_allnodes being sorted differently from the child
lists.
- Support for retrieving original DTB blob via sysfs. Needed by kexec.
- More unittests
- Documentation and minor bug fixes
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Merge tag 'devicetree-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/glikely/linux
Pull devicetree changes from Grant Likely:
"Lots of activity in the devicetree code for v3.18. Most of it is
related to getting all of the overlay support code in place, but there
are other important things in there.
Highlights:
- OF_RECONFIG notifiers for SPI, I2C and Platform devices. Those
subsystems can now respond to live changes to the device tree.
- CONFIG_OF_OVERLAY method for applying live changes to the device
tree
- Removal of the of_allnodes list. This used to be used to iterate
over all the nodes in the device tree, but it is unnecessary
because the same thing can be done by iterating over the list of
child pointers. Getting rid of of_allnodes saves some memory and
avoids the possibility of of_allnodes being sorted differently from
the child lists.
- Support for retrieving original DTB blob via sysfs. Needed by
kexec.
- More unittests
- Documentation and minor bug fixes"
* tag 'devicetree-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/glikely/linux: (42 commits)
of: Delete unnecessary check before calling "of_node_put()"
of: Drop ->next pointer from struct device_node
spi: Check for spi_of_notifier when CONFIG_OF_DYNAMIC=y
of: support passing console options with stdout-path
of: add optional options parameter to of_find_node_by_path()
of: Add bindings for chosen node, stdout-path
of: Remove unneeded and incorrect MODULE_DEVICE_TABLE
ARM: dt: fix up PL011 device tree bindings
of: base, fix of_property_read_string_helper kernel-doc
of: remove select of non-existant OF_DEVICE config symbol
spi/of: Add OF notifier handler
spi/of: Create new device registration method and accessors
i2c/of: Add OF_RECONFIG notifier handler
i2c/of: Factor out Devicetree registration code
of/overlay: Add overlay unittests
of/overlay: Introduce DT overlay support
of/reconfig: Add OF_DYNAMIC notifier for platform_bus_type
of/reconfig: Always use the same structure for notifiers
of/reconfig: Add debug output for OF_RECONFIG notifiers
of/reconfig: Add empty stubs for the of_reconfig methods
...
CONFIG_OF_DYNAMIC enables runtime changes to the device tree which in
turn may trigger addition or removal of devices from Linux. Add an
OF_RECONFIG notifier handler to receive tree change events and to
creating or destroy i2c devices as required.
Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
[grant.likely: clean up #ifdefs and drop unneeded error handling]
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Reviewed-by: Wolfram Sang <wsa@the-dreams.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-i2c@vger.kernel.org
Dynamically inserting i2c client device nodes requires the use
of a single device registration method. Factor out the loop body of
of_i2c_register_devices() so that it can be called for individual
device_nodes instead of for all the children of a node.
Note: The diff of this commit looks far more complicated than it
actually is due the indentation being changed for a large block of code.
When viewed using the diff -w flag to ignore whitespace changes it can
be seen that the change is actually quite simple.
Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>
[grant.likely: Made new function static and removed changes to header]
Signed-off-by: Grant Likely <grant.likely@linaro.org>
Reviewed-by: Wolfram Sang <wsa@the-dreams.de>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: linux-i2c@vger.kernel.org
ACPI 5.0 introduces _DEP (Operation Region Dependencies) to designate
device objects that OSPM should assign a higher priority in start
ordering due to future operation region accesses.
On Asus T100TA, ACPI battery info are read from a I2C slave device via
I2C operation region. Before I2C operation region handler is installed,
battery _STA always returns 0. There is a _DEP method of designating
start order under battery device node.
This patch is to implement _DEP feature to fix battery issue on the
Asus T100TA. Introducing acpi_dep_list and adding dep_unmet count
in struct acpi_device. During ACPI namespace scan, create struct
acpi_dep_data for a valid pair of master (device pointed to by _DEP)/
slave(device with _DEP), record master's and slave's ACPI handle in
it and put it into acpi_dep_list. The dep_unmet count will increase
by one if there is a device under its _DEP. Driver's probe() should
return EPROBE_DEFER when find dep_unmet is larger than 0. When I2C
operation region handler is installed, remove all struct acpi_dep_data
on the acpi_dep_list whose master is pointed to I2C host controller
and decrease slave's dep_unmet. When dep_unmet decreases to 0, all
_DEP conditions are met and then do acpi_bus_attach() for the device
in order to resolve battery _STA issue on the Asus T100TA.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=69011
Tested-by: Jan-Michael Brummer <jan.brummer@tabos.org>
Tested-by: Adam Williamson <adamw@happyassassin.net>
Tested-by: Michael Shigorin <shigorin@gmail.com>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
No need to initialize 'ret' if it gets assigned directly after that.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Since commit 2fd36c5526 ("i2c: core: Map OF IRQ at probe time"),
i2c slaves without interrupts (e.g. da9210 and at24 on r8a7791/koelsch)
fail to probe:
at24: probe of 2-0050 failed with error -22
da9210: probe of 6-0068 failed with error -22
This happens because the call to of_irq_get() in i2c_device_probe()
returns -EINVAL.
If a device node does not have an "interrupts" property,
of_irq_parse_one() fails. Unlike irq_of_parse_and_map(), of_irq_get()
does not ignore errors from of_irq_parse_one(), but forwards them.
Make i2c_device_probe() ignore all errors but -EPROBE_DEFER to fix this,
just like platform_get_irq() and platform_get_irq_byname() already do.
Fixes: 2fd36c5526 ("i2c: core: Map OF IRQ at probe time")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
I2C clients instantiated from OF get their IRQ mapped at device
registration time. This leads to the IRQ being silently ignored if the
related irqchip hasn't been proved yet.
Fix this by moving IRQ mapping at probe time using of_get_irq(). The
function operates as irq_of_parse_and_map() but additionally returns
-EPROBE_DEFER if the irqchip isn't available, allowing us to defer I2C
client probing.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Clients instantiated from OF get an IRQ mapping created at device
registration time. Dispose the mapping when the client is removed.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Cc: stable@kernel.org
The commit 46420dd73b (PM / Domains: Add APIs to attach/detach a PM
domain for a device) started using errno values in pm.h header file.
It also failed to include the header for these, thus it caused
compiler errors.
Instead of including the errno header to pm.h, let's move the functions
to pm_domain.h, since it's a better match.
Fixes: 46420dd73b (PM / Domains: Add APIs to attach/detach a PM domain for a device)
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
If adapter->dev.parent == NULL there is a NULL pointer dereference in
acpi_i2c_install_space_handler and acpi_i2c_remove_space_handler.
This is present since introduction of this code:
366047515c "i2c: rework kernel config I2C_ACPI" or even
da3c6647ee "I2C/ACPI: Clean up I2C ACPI code and Add CONFIG_I2C_ACPI"
The adapter->dev.parent == NULL case is valid for the i2c_stub,
so loading i2c_stub with ACPI_I2C_OPREGION enabled results in an oops.
This is also valid at least for i2c_tiny_usb and i2c_robotfuzz_osif.
Fix by checking whether it is null before calling ACPI_HANDLE.
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Commit 5d98e61d33 ("I2C/ACPI: Add i2c ACPI operation region support")
renamed the i2c-core module. This may cause regressions for
distributions, so put the ACPI code back into the core.
Reported-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Tested-by: Lan Tianyu <tianyu.lan@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Previously only the ACPI PM domain was supported by the i2c bus.
Let's convert to the common attach/detach functions for PM domains,
which currently means we are extending the support to include the
generic PM domain as well.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Kevin Hilman <khilman@linaro.org>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Reviewed-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Pull i2c updates from Wolfram Sang:
"Highlights:
- class based instantiation finally dropped for most embedded drivers
bringing boot up performance gains
- removed two drivers (one outdated, one a duplicate)
- ACPI has now operation region support (thanks to Lan Tianyu)
- the i2c-stub driver got overhauled and gained new features to
become more useful when writing i2c client drivers (thanks to
Guenter Roeck and Jean Delvare)
The rest is driver bugfixes, added bindings/ids, cleanups..."
* 'i2c/for-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (43 commits)
i2c: mpc: delete unneeded test before of_node_put
i2c: rk3x: fix interrupt handling issue
i2c: imx: Fix format warning for dev_dbg
i2c: qup: disable clks and return instead of just returning error
i2c: exynos5: always enable HSI2C
i2c: designware: add new bindings
i2c: gpio: Drop dead code in i2c_gpio_remove
i2c: pca954x: put the mux to disconnected state after resume
i2c: st: Update i2c timings
drivers/i2c/busses: use correct type for dma_map/unmap
i2c: i2c-st: Use %pa to print 'resource_size_t' type
i2c: s3c2410: resume the I2C controller earlier
i2c: stub: Avoid an array overrun on I2C block transfers
i2c: i801: Add device ID for Intel Wildcat Point PCH
i2c: i801: Fix the alignment of the device table
i2c: stub: Add support for banked register ranges
i2c: stub: Remember the number of emulated chips
i2c: stub: Add support for SMBus block commands
i2c: efm32: correct namespacing of location property
i2c: exynos5: remove extra line and fix an assignment
...
This patch adds helper functions to configure clock parents and rates
as specified through 'assigned-clock-parents', 'assigned-clock-rates'
DT properties for a clock provider or clock consumer device.
The helpers are now being called by the bus code for the platform, I2C
and SPI busses, before the driver probing and also in the clock core
after registration of a clock provider.
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
We have a warning already when support for old-fashioned class based
instantiation is about to be dropped somewhen soon from a driver. Let's
have another one when it was actually dropped. This allows to remove the
cruft a little earlier and still let users know what happened in the
rare case they are missing devices after the change. However, there is
enough interest to get rid of class based instantiation rather sooner
than later because it improves boot up time.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Clean up ACPI related code in the i2c core and add CONFIG_I2C_ACPI
to enable I2C ACPI code.
Current there is a race between removing I2C ACPI operation region
and ACPI AML code accessing. So make i2c core built-in if CONFIG_I2C_ACPI
is set.
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
ACPI 5.0 spec(5.5.2.4.5) defines GenericSerialBus(i2c, spi, uart) operation region.
It allows ACPI aml code able to access such kind of devices to implement
some ACPI standard method.
ACPI Spec defines some access attribute to associate with i2c protocol.
AttribQuick Read/Write Quick Protocol
AttribSendReceive Send/Receive Byte Protocol
AttribByte Read/Write Byte Protocol
AttribWord Read/Write Word Protocol
AttribBlock Read/Write Block Protocol
AttribBytes Read/Write N-Bytes Protocol
AttribProcessCall Process Call Protocol
AttribBlockProcessCall Write Block-Read Block Process Call Protocol
AttribRawBytes Raw Read/Write N-BytesProtocol
AttribRawProcessBytes Raw Process Call Protocol
On the Asus T100TA, Bios use GenericSerialBus operation region to access
i2c device to get battery info.
Sample code From Asus T100TA
Scope (_SB.I2C1)
{
Name (UMPC, ResourceTemplate ()
{
I2cSerialBus (0x0066, ControllerInitiated, 0x00061A80,
AddressingMode7Bit, "\\_SB.I2C1",
0x00, ResourceConsumer, ,
)
})
...
OperationRegion (DVUM, GenericSerialBus, Zero, 0x0100)
Field (DVUM, BufferAcc, NoLock, Preserve)
{
Connection (UMPC),
Offset (0x81),
AccessAs (BufferAcc, AttribBytes (0x3E)),
FGC0, 8
}
...
}
Device (BATC)
{
Name (_HID, EisaId ("PNP0C0A")) // _HID: Hardware ID
Name (_UID, One) // _UID: Unique ID
...
Method (_BST, 0, NotSerialized) // _BST: Battery Status
{
If (LEqual (AVBL, One))
{
Store (FGC0, BFFG)
If (LNotEqual (STAT, One))
{
ShiftRight (CHST, 0x04, Local0)
And (Local0, 0x03, Local0)
If (LOr (LEqual (Local0, One), LEqual (Local0, 0x02)))
{
Store (0x02, Local1)
}
...
}
The i2c operation region is defined under I2C1 scope. _BST method under
battery device BATC read battery status from the field "FCG0". The request
would be sent to i2c operation region handler.
This patch is to add i2c ACPI operation region support. Due to there are
only "Byte" and "Bytes" protocol access on the Asus T100TA, other protocols
have not been tested.
About RawBytes and RawProcessBytes protocol, they needs specific drivers to interpret
reference data from AML code according ACPI 5.0 SPEC(5.5.2.4.5.3.9 and 5.5.2.4.5.3.10).
So far, not found such case and will add when find real case.
Signed-off-by: Lan Tianyu <tianyu.lan@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The SMBUS tracepoints can be enabled thusly:
echo 1 >/sys/kernel/debug/tracing/events/i2c/enable
and will dump messages that can be viewed in /sys/kernel/debug/tracing/trace
that look like:
... smbus_read: i2c-0 a=051 f=0000 c=fa BYTE_DATA
... smbus_reply: i2c-0 a=051 f=0000 c=fa BYTE_DATA l=1 [39]
... smbus_result: i2c-0 a=051 f=0000 c=fa BYTE_DATA rd res=0
formatted as:
i2c-<adapter-nr>
a=<addr>
f=<flags>
c=<command>
<protocol-name>
<rd|wr>
res=<result>
l=<data-len>
[<data-block>]
The adapters to be traced can be selected by something like:
echo adapter_nr==1 >/sys/kernel/debug/tracing/events/i2c/filter
Note that this shares the same filter and enablement as i2c.
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Add tracepoints into the I2C message transfer function to retrieve the message
sent or received. The following config options must be turned on to make use
of the facility:
CONFIG_FTRACE
CONFIG_ENABLE_DEFAULT_TRACERS
The I2C tracepoint can be enabled thusly:
echo 1 >/sys/kernel/debug/tracing/events/i2c/enable
and will dump messages that can be viewed in /sys/kernel/debug/tracing/trace
that look like:
... i2c_write: i2c-5 #0 a=044 f=0000 l=2 [02-14]
... i2c_read: i2c-5 #1 a=044 f=0001 l=4
... i2c_reply: i2c-5 #1 a=044 f=0001 l=4 [33-00-00-00]
... i2c_result: i2c-5 n=2 ret=2
formatted as:
i2c-<adapter-nr>
#<message-array-index>
a=<addr>
f=<flags>
l=<datalen>
n=<message-array-size>
ret=<result>
[<data>]
The operation is done between the i2c_write/i2c_read lines and the i2c_reply
and i2c_result lines so that if the hardware hangs, the trace buffer can be
consulted to determine the problematic operation.
The adapters to be traced can be selected by something like:
echo adapter_nr==1 >/sys/kernel/debug/tracing/events/i2c/filter
These changes are based on code from Steven Rostedt.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Steven Rostedt <rostedt@goodmis.org>
[wsa: adapted path for 'enable' in the commit msg]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Class based instantiation can cause noticeable delays when booting. This
mechanism is used when it is not possible to describe slaves on I2C
busses. As we do have other mechanisms, most embedded I2C will not need
classes and for embedded it is explicitly not recommended to use them. Add
a deprecation warning for drivers which want to disable class based
instantiation in the near future to gain boot-up time, so users relying
on this technique can switch to something better. They really should.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Pull more i2c updates from Wolfram Sang:
"Mostly bugfixes, small but wanted cleanups, and Paul's init.h removal
applied"
* 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux:
i2c: rcar: fix NACK error code
i2c: update i2c_algorithm documentation
i2c: rcar: use devm_clk_get to ensure clock is properly ref-counted
i2c: rcar: do not print error if device nacks transfer
i2c: rely on driver core when sanitizing devices
i2c: delete non-required instances of include <linux/init.h>
i2c: acorn: is tristate and should use module.h
i2c: piix4: Standardize log messages
i2c: piix4: Use different message for AMD Auxiliary SMBus Controller
i2c: piix4: Add support for AMD ML and CZ SMBus changes
Pull hwmon updates from Jean Delvare:
"This include it87 driver improvements, and a tree-wide change of my
e-mail address"
* 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
Update Jean Delvare's e-mail address
hwmon: (it87) Print proper names for the IT8771E and IT8772E
hwmon: (it87) Add support for the ITE IT8603E
Commit 0998d06310 (device-core: Ensure drvdata = NULL when no driver
is bound) modified the driver core to always clear .driver and .drvdata
on remove or probe error. No need for the I2C core to do it.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
ACPI enumerated devices has ACPI style _HID and _CID strings,
all of these strings can be used for both driver loading and matching.
Currently, in Platform, I2C and SPI bus, the ACPI style driver matching
is supported by invoking acpi_driver_match_device() in bus .match() callback.
But, the module autoloading is still broken.
For example, there is any ACPI device with _HID "INTABCD" that is
enumerated to platform bus, and we have a driver that can probe it.
The driver exports its module_alias as "acpi:INTABCD" use the following code
static const struct acpi_device_id xxx_acpi_match[] = {
{ "INTABCD", 0 },
{ }
};
MODULE_DEVICE_TABLE(acpi, xxx_acpi_match);
But, unfortunately, the device' modalias is shown as "platform:INTABCD:00",
please refer to modalias_show() and platform_uevent() in
drivers/base/platform.c.
This results in that the driver will not be loaded automatically when the
device node is created, because their modalias do not match.
This also applies to I2C and SPI bus.
With this patch, the device' modalias will be shown as "acpi:INTABCD" as well.
Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Acked-by: Mark Brown <broonie@linaro.org>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
- ACPI-based device hotplug fixes for issues introduced recently and
a fix for an older error code path bug in the ACPI PCI host bridge
driver.
- Fix for recently broken OMAP cpufreq build from Viresh Kumar.
- Fix for a recent hibernation regression related to s2disk.
- Fix for a locking-related regression in the ACPI EC driver from
Puneet Kumar.
- System suspend error code path fix related to runtime PM and
runtime PM documentation update from Ulf Hansson.
- cpufreq's conservative governor fix from Xiaoguang Chen.
- New processor IDs for intel_idle and turbostat and removal of
an obsolete Kconfig option from Len Brown.
- New device IDs for the ACPI LPSS (Low-Power Subsystem) driver and
ACPI-based PCI hotplug (ACPIPHP) cleanup from Mika Westerberg.
- Removal of several ACPI video DMI blacklist entries that are not
necessary any more from Aaron Lu.
- Rework of the ACPI companion representation in struct device and
code cleanup related to that change from Rafael J Wysocki,
Lan Tianyu and Jarkko Nikula.
- Fixes for assigning names to ACPI-enumerated I2C and SPI devices
from Jarkko Nikula.
/
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Merge tag 'pm+acpi-2-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull more ACPI and power management updates from Rafael Wysocki:
- ACPI-based device hotplug fixes for issues introduced recently and a
fix for an older error code path bug in the ACPI PCI host bridge
driver
- Fix for recently broken OMAP cpufreq build from Viresh Kumar
- Fix for a recent hibernation regression related to s2disk
- Fix for a locking-related regression in the ACPI EC driver from
Puneet Kumar
- System suspend error code path fix related to runtime PM and runtime
PM documentation update from Ulf Hansson
- cpufreq's conservative governor fix from Xiaoguang Chen
- New processor IDs for intel_idle and turbostat and removal of an
obsolete Kconfig option from Len Brown
- New device IDs for the ACPI LPSS (Low-Power Subsystem) driver and
ACPI-based PCI hotplug (ACPIPHP) cleanup from Mika Westerberg
- Removal of several ACPI video DMI blacklist entries that are not
necessary any more from Aaron Lu
- Rework of the ACPI companion representation in struct device and code
cleanup related to that change from Rafael J Wysocki, Lan Tianyu and
Jarkko Nikula
- Fixes for assigning names to ACPI-enumerated I2C and SPI devices from
Jarkko Nikula
* tag 'pm+acpi-2-3.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (24 commits)
PCI / hotplug / ACPI: Drop unused acpiphp_debug declaration
ACPI / scan: Set flags.match_driver in acpi_bus_scan_fixed()
ACPI / PCI root: Clear driver_data before failing enumeration
ACPI / hotplug: Fix PCI host bridge hot removal
ACPI / hotplug: Fix acpi_bus_get_device() return value check
cpufreq: governor: Remove fossil comment in the cpufreq_governor_dbs()
ACPI / video: clean up DMI table for initial black screen problem
ACPI / EC: Ensure lock is acquired before accessing ec struct members
PM / Hibernate: Do not crash kernel in free_basic_memory_bitmaps()
ACPI / AC: Remove struct acpi_device pointer from struct acpi_ac
spi: Use stable dev_name for ACPI enumerated SPI slaves
i2c: Use stable dev_name for ACPI enumerated I2C slaves
ACPI: Provide acpi_dev_name accessor for struct acpi_device device name
ACPI / bind: Use (put|get)_device() on ACPI device objects too
ACPI: Eliminate the DEVICE_ACPI_HANDLE() macro
ACPI / driver core: Store an ACPI device pointer in struct acpi_dev_node
cpufreq: OMAP: Fix compilation error 'r & ret undeclared'
PM / Runtime: Fix error path for prepare
PM / Runtime: Update documentation around probe|remove|suspend
cpufreq: conservative: set requested_freq to policy max when it is over policy max
...
Pull i2c changes from Wolfram Sang:
- new drivers for exynos5, bcm kona, and st micro
- bigger overhauls for drivers mxs and rcar
- typical driver bugfixes, cleanups, improvements
- got rid of the superfluous 'driver' member in i2c_client struct This
touches a few drivers in other subsystems. All acked.
* 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (38 commits)
i2c: bcm-kona: fix error return code in bcm_kona_i2c_probe()
i2c: i2c-eg20t: do not print error message in syslog if no ACK received
i2c: bcm-kona: Introduce Broadcom I2C Driver
i2c: cbus-gpio: Fix device tree binding
i2c: wmt: add missing clk_disable_unprepare() on error
i2c: designware: add new ACPI IDs
i2c: i801: Add Device IDs for Intel Wildcat Point-LP PCH
i2c: exynos5: Remove incorrect clk_disable_unprepare
i2c: i2c-st: Add ST I2C controller
i2c: exynos5: add High Speed I2C controller driver
i2c: rcar: fixup rcar type naming
i2c: scmi: remove some bogus NULL checks
i2c: sh_mobile & rcar: Enable the driver on all ARM platforms
i2c: sh_mobile: Convert to clk_prepare/unprepare
i2c: mux: gpio: use reg value for i2c_add_mux_adapter
i2c: mux: gpio: use gpio_set_value_cansleep()
i2c: Include linux/of.h header
i2c: mxs: Fix PIO mode on i.MX23
i2c: mxs: Rework the PIO mode operation
i2c: mxs: distinguish i.MX23 and i.MX28 based I2C controller
...
Current I2C adapter id - client address "x-00yy" based device naming scheme
is not always stable enough to be used in name based matching, for instance
within ALSA SoC subsystem.
This is problematic in PC kind of platforms where I2C adapter numbers can
change due variable amount of bus controllers, probe order, add-on cards or
just because of BIOS settings.
This patch addresses the problem by using the ACPI device name with
"i2c-" prefix for ACPI enumerated I2C slaves. For them device name
"x-00yz" becomes "i2c-INTABCD:ij" after this patch.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Modify struct acpi_dev_node to contain a pointer to struct acpi_device
associated with the given device object (that is, its ACPI companion
device) instead of an ACPI handle corresponding to it. Introduce two
new macros for manipulating that pointer in a CONFIG_ACPI-safe way,
ACPI_COMPANION() and ACPI_COMPANION_SET(), and rework the
ACPI_HANDLE() macro to take the above changes into account.
Drop the ACPI_HANDLE_SET() macro entirely and rework its users to
use ACPI_COMPANION_SET() instead. For some of them who used to
pass the result of acpi_get_child() directly to ACPI_HANDLE_SET()
introduce a helper routine acpi_preset_companion() doing an
equivalent thing.
The main motivation for doing this is that there are things
represented by struct acpi_device objects that don't have valid
ACPI handles (so called fixed ACPI hardware features, such as
power and sleep buttons) and we would like to create platform
device objects for them and "glue" them to their ACPI companions
in the usual way (which currently is impossible due to the
lack of valid ACPI handles). However, there are more reasons
why it may be useful.
First, struct acpi_device pointers allow of much better type checking
than void pointers which are ACPI handles, so it should be more
difficult to write buggy code using modified struct acpi_dev_node
and the new macros. Second, the change should help to reduce (over
time) the number of places in which the result of ACPI_HANDLE() is
passed to acpi_bus_get_device() in order to obtain a pointer to the
struct acpi_device associated with the given "physical" device,
because now that pointer is returned by ACPI_COMPANION() directly.
Finally, the change should make it easier to write generic code that
will build both for CONFIG_ACPI set and unset without adding explicit
compiler directives to it.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com> # on Haswell
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Aaron Lu <aaron.lu@intel.com> # for ATA and SDIO part
* acpi-pm:
spi: attach/detach SPI device to the ACPI power domain
i2c: attach/detach I2C client device to the ACPI power domain
ACPI / PM: allow child devices to ignore parent power state
If the I2C client device is enumerated from ACPI namespace it might have
ACPI methods that needs to be called in order to transition the device to
different power states (such as _PSx).
Implement this for I2C client devices by checking if the device has an ACPI
handle and if that's the case, attach it to the ACPI power domain. In
addition we make sure that the device is fully powered when its ->probe()
function gets called.
For non-ACPI devices this patch is a no-op.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The code in acpi_i2c_register_devices() assumes that all i2c adapters
have a parent. This is not necessarily the case, for example the
i2c-stub driver instantiate a virtual i2c adapter without a parent.
Check for this to avoid a NULL pointer deference.
Signed-off-by: Jean Delvare <jdelvare@suse.de>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The 'driver' field of the i2c_client struct is redundant. The same data can be
accessed through to_i2c_driver(client->dev.driver). The generated code for both
approaches in more or less the same.
E.g. on ARM the expression client->driver->command(...) generates
...
ldr r3, [r0, #28]
ldr r3, [r3, #32]
blx r3
...
and the expression to_i2c_driver(client->dev.driver)->command(...) generates
...
ldr r3, [r0, #160]
ldr r3, [r3, #-4]
blx r3
...
Other architectures will generate similar code.
All users of the 'driver' field outside of the I2C core have already been
converted. So this only leaves the core itself. This patch converts the
remaining few users in the I2C core and then removes the 'driver' field from the
i2c_client struct.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This follows what has already been done for the DeviceTree helpers. Move
the ACPI helpers from drivers/acpi/acpi_i2c.c to the I2C core and update
documentation accordingly.
This also solves a problem reported by Jerry Snitselaar that we can't build
the ACPI I2C helpers as a module.
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
I2C of helpers used to live in of_i2c.c but experience (from SPI) shows
that it is much cleaner to have this in the core. This also removes a
circular dependency between the helpers and the core, and so we can
finally register child nodes in the core instead of doing this manually
in each driver. So, fix the drivers and documentation, too.
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
While writing the i2c-imc driver, I noticed that the warning message
when the i2c core can't figure out how to probe is mostly useless.
This trivial patch improves it.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
i2c_put_adapter dereferences i2c_adapter pointer passed without check
for NULL. This adds a check for non-NULL pointer to allow i2c_put_adapter
called with NULL and behave the same way i2c_release_client does already.
It allows to simplify drivers where you need to release the adapter
during probe failures.
Signed-off-by: Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The "runtime idle" helper routine, rpm_idle(), currently ignores
return values from .runtime_idle() callbacks executed by it.
However, it turns out that many subsystems use
pm_generic_runtime_idle() which checks the return value of the
driver's callback and executes pm_runtime_suspend() for the device
unless that value is not 0. If that logic is moved to rpm_idle()
instead, pm_generic_runtime_idle() can be dropped and its users
will not need any .runtime_idle() callbacks any more.
Moreover, the PCI, SCSI, and SATA subsystems' .runtime_idle()
routines, pci_pm_runtime_idle(), scsi_runtime_idle(), and
ata_port_runtime_idle(), respectively, as well as a few drivers'
ones may be simplified if rpm_idle() calls rpm_suspend() after 0 has
been returned by the .runtime_idle() callback executed by it.
To reduce overall code bloat, make the changes described above.
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Kevin Hilman <khilman@linaro.org>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
i2c: suppress lockdep warning on delete_device
Since commit 846f99749a the following lockdep
warning is thrown in case i2c device is removed (via delete_device sysfs
attribute) which contains subdevices (e.g. i2c multiplexer):
=============================================
[ INFO: possible recursive locking detected ]
3.8.7-0-sampleversion-fct #8 Tainted: G O
---------------------------------------------
bash/3743 is trying to acquire lock:
(s_active#110){++++.+}, at: [<ffffffff802b3048>] sysfs_hash_and_remove+0x58/0xc8
but task is already holding lock:
(s_active#110){++++.+}, at: [<ffffffff802b3cb8>] sysfs_write_file+0xc8/0x208
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(s_active#110);
lock(s_active#110);
*** DEADLOCK ***
May be due to missing lock nesting notation
4 locks held by bash/3743:
#0: (&buffer->mutex){+.+.+.}, at: [<ffffffff802b3c3c>] sysfs_write_file+0x4c/0x208
#1: (s_active#110){++++.+}, at: [<ffffffff802b3cb8>] sysfs_write_file+0xc8/0x208
#2: (&adap->userspace_clients_lock/1){+.+.+.}, at: [<ffffffff80454a18>] i2c_sysfs_delete_device+0x90/0x238
#3: (&__lockdep_no_validate__){......}, at: [<ffffffff803dcc24>] device_release_driver+0x24/0x48
stack backtrace:
Call Trace:
[<ffffffff80575cc8>] dump_stack+0x8/0x34
[<ffffffff801b50fc>] __lock_acquire+0x161c/0x2110
[<ffffffff801b5c3c>] lock_acquire+0x4c/0x70
[<ffffffff802b60cc>] sysfs_addrm_finish+0x19c/0x1e0
[<ffffffff802b3048>] sysfs_hash_and_remove+0x58/0xc8
[<ffffffff802b7d8c>] sysfs_remove_group+0x64/0x148
[<ffffffff803d990c>] device_remove_attrs+0x9c/0x1a8
[<ffffffff803d9b1c>] device_del+0x104/0x1d8
[<ffffffff803d9c18>] device_unregister+0x28/0x70
[<ffffffff8045505c>] i2c_del_adapter+0x1cc/0x328
[<ffffffff8045802c>] i2c_del_mux_adapter+0x14/0x38
[<ffffffffc025c108>] pca954x_remove+0x90/0xe0 [pca954x]
[<ffffffff804542f8>] i2c_device_remove+0x80/0xe8
[<ffffffff803dca9c>] __device_release_driver+0x74/0xf8
[<ffffffff803dcc2c>] device_release_driver+0x2c/0x48
[<ffffffff803dbc14>] bus_remove_device+0x13c/0x1d8
[<ffffffff803d9b24>] device_del+0x10c/0x1d8
[<ffffffff803d9c18>] device_unregister+0x28/0x70
[<ffffffff80454b08>] i2c_sysfs_delete_device+0x180/0x238
[<ffffffff802b3cd4>] sysfs_write_file+0xe4/0x208
[<ffffffff8023ddc4>] vfs_write+0xbc/0x160
[<ffffffff8023df6c>] SyS_write+0x54/0xd8
[<ffffffff8013d424>] handle_sys64+0x44/0x64
The problem is already known for USB and PCI subsystems. The reason is that
delete_device attribute is defined statically in i2c-core.c and used for all
devices in i2c subsystem.
Discussion of original USB problem:
http://lkml.indiana.edu/hypermail/linux/kernel/1204.3/01160.html
Commit 356c05d58a introduced new macro to suppress
lockdep warnings for this special case and included workaround for USB code.
LKML discussion of the workaround:
http://lkml.indiana.edu/hypermail/linux/kernel/1205.1/03634.html
As i2c case is in principle the same, the same workaround could be used here.
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nsn.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
CONFIG_HOTPLUG is going away as an option, cleanup CONFIG_HOTPLUG
ifdefs in i2c files.
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
i2c_del_adapter() is usually called from a drivers remove callback. The Linux
device driver model does not allow the remove callback to fail and all resources
allocated in the probe callback need to be freed, as well as all resources which
have been provided to the rest of the kernel(for example a I2C adapter) need to
be revoked. So any function revoking such resources isn't allowed to fail
either. i2c_del_adapter() adheres to this requirement and will never fail. But
i2c_del_adapter()'s return type is int, which may cause driver authors to think
that it can fail. This led to code constructs like:
ret = i2c_del_adapter(...);
BUG_ON(ret);
Since i2c_del_adapter() always returns 0 the BUG_ON is never hit and essentially
becomes dead code, which means it can be removed. Making the return type of
i2c_del_adapter() void makes it explicit that the function will never fail and
should prevent constructs like the above from re-appearing in the kernel code.
All callers of i2c_del_adapter() have already been updated in a previous patch
to ignore the return value, so the conversion of the return type from int to
void can be done without causing any build failures.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Reviewed-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Currently i2c_del_adapter() returns -EINVAL when it gets an adapter which is not
registered. But none of the users of i2c_del_adapter() depend on this behavior,
so for the sake of being able to sanitize the return type of i2c_del_adapter
argue, that the purpose of i2c_del_adapter() is to remove an I2C adapter from
the system. If the adapter is not registered in the first place this becomes a
no-op. So we can return success without having to do anything.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Reviewed-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
The detach_adapter callback has been deprecated for quite some time and has no
user left. Keeping it alive blocks other cleanups, so remove it.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Reviewed-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Add i2c bus recovery infrastructure to i2c adapters as specified in the i2c
protocol Rev. 03 section 3.1.16 titled "Bus clear".
http://www.nxp.com/documents/user_manual/UM10204.pdf
Sometimes during operation i2c bus hangs and we need to give dummy clocks to
slave device to start the transfer again. Now we may have capability in the bus
controller to generate these clocks or platform may have gpio pins which can be
toggled to generate dummy clocks. This patch supports both.
This patch also adds in generic bus recovery routines gpio or scl line based
which can be used by bus controller. In addition controller driver may provide
its own version of the bus recovery routine.
This doesn't support multi-master recovery for now.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[wsa: changed gpio type to int and minor reformatting]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This allows you to get the equivalent functionality of
i2c_add_numbered_adapter() with all data in the device tree and no
special case code in your driver. This is a common device tree
technique.
For quick reference, the FDT syntax for using an alias to provide an
ID looks like:
aliases {
i2c0 = &i2c_0;
i2c1 = &i2c_1;
};
Signed-off-by: Doug Anderson <dianders@chromium.org>
[wsa: removed one check from static function. We know our callers]
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
