In the match() callback, the struct device_driver * should not be
changed, so change the function callback to be a const *. This is one
step of many towards making the driver core safe to have struct
device_driver in read-only memory.
Because the match() callback is in all busses, all busses are modified
to handle this properly. This does entail switching some container_of()
calls to container_of_const() to properly handle the constant *.
For some busses, like PCI and USB and HV, the const * is cast away in
the match callback as those busses do want to modify those structures at
this point in time (they have a local lock in the driver structure.)
That will have to be changed in the future if they wish to have their
struct device * in read-only-memory.
Cc: Rafael J. Wysocki <rafael@kernel.org>
Reviewed-by: Alex Elder <elder@kernel.org>
Acked-by: Sumit Garg <sumit.garg@linaro.org>
Link: https://lore.kernel.org/r/2024070136-wrongdoer-busily-01e8@gregkh
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Fix up a few places in the platform core code that can easily handle
struct device_driver being constant. This is part of the work to make
all struct device_driver pointers be constant.
Cc: Rafael J. Wysocki <rafael@kernel.org>
Link: https://lore.kernel.org/r/20240611130103.3262749-8-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
struct platform_driver::remove returning an integer made driver authors
expect that returning an error code was proper error handling. However
the driver core ignores the error and continues to remove the device
because there is nothing the core could do anyhow and reentering the
remove callback again is only calling for trouble.
To prevent such wrong assumptions, change the return type of the remove
callback to void. This was prepared by introducing an alternative remove
callback returning void and converting all drivers to that. So .remove()
can be changed without further changes in drivers.
This corresponds to step b) of the plan outlined in commit
5c5a7680e6 ("platform: Provide a remove callback that returns no value").
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time via CONFIG_UBSAN_BOUNDS (for
array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).
As found with Coccinelle[1], add __counted_by for struct
irq_affinity_devres.
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Cc: linux-hardening@vger.kernel.org
Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1]
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20231006201749.work.432-kees@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
OF and ACPI currently are using asymmetrical APIs to check
for the firmware node type. Unify them by using is_*_node()
against struct fwnode_handle pointer.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20231003142122.3072824-4-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
With the temporary variable for the struct device pointer the code
looks better and slightly easier to read and parse by human being.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20231003142122.3072824-3-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The usual pattern is to bail out on the error case. Besides that
one of the labels is redundant as we may return directly. Refactor
platform_device_add() and platform_dma_configure() accordingly.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20231003142122.3072824-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Starting from the commit 37c12e7497 ("[DRIVER MODEL] Improved
dynamically allocated platform_device interface") the pdev expects
to be allocated beforehand or guaranteed to be non-NULL.
Hence the leftover check is now redundant (as we have no combined
calls like platform_device_add(platform_device_alloc(...)) in the
entire kernel source code.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20231003142122.3072824-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There's no reason the generic platform bus code needs to call
of_platform_register_reconfig_notifier(). The notifier can be setup
before the platform bus is. Let's move it into of_core_init() which is
called just before platform_bus_init() instead to keep more of the DT
bits in the DT code.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20230717143718.1715773-1-robh@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
__platform_driver_probe() pokes around in some bus and driver private
lists and locks in a way that is not needed at all. The code only wants
to know if a device was bound to the driver that was registered, so walk
all devices on the bus to see if there was a match. If there is not a
match, return an error. This is the same logic as was originally
present, but just done in a simpler and more obvious way that is not a
layering violation.
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Link: https://lore.kernel.org/r/20230131082459.301603-2-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In the reworking of the function __platform_driver_probe() over the
years, it turns out that the variable 'code' does not actually do
anything or mean anything anymore and can be removed to simplify the
logic when trying to read and understand what this function is actually
doing.
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Link: https://lore.kernel.org/r/20230131082459.301603-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The uevent() callback in struct bus_type should not be modifying the
device that is passed into it, so mark it as a const * and propagate the
function signature changes out into all relevant subsystems that use
this callback.
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20230111113018.459199-16-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When CONFIG_OF_IRQ is not enabled, there will be a stub method that always
returns 0 when getting IRQ. Thus, the if-branch can be removed safely.
Signed-off-by: Soha Jin <soha@lohu.info>
Link: https://lore.kernel.org/r/20221111094542.270540-1-soha@lohu.info
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
struct platform_driver::remove returning an integer made driver authors
expect that returning an error code was proper error handling. However
the driver core ignores the error and continues to remove the device
because there is nothing the core could do anyhow and reentering the
remove callback again is only calling for trouble.
So this is an source for errors typically yielding resource leaks in the
error path.
As there are too many platform drivers to neatly convert them all to
return void in a single go, do it in several steps after this patch:
a) Convert all drivers to implement .remove_new() returning void instead
of .remove() returning int;
b) Change struct platform_driver::remove() to return void and so make
it identical to .remove_new();
c) Change all drivers back to .remove() now with the better prototype;
d) drop struct platform_driver::remove_new().
While this touches all drivers eventually twice, steps a) and c) can be
done one driver after another and so reduces coordination efforts
immensely and simplifies review.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20221209150914.3557650-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Not only platform devices described by OF have named interrupts, but
devices described by ACPI also have named interrupts. The fwnode is an
abstraction to different standards, and using fwnode_irq_get_byname can
support more devices.
Signed-off-by: Soha Jin <soha@lohu.info>
Tested-by: Wende Tan <twd2.me@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Here is the set of driver core changes for 5.19-rc1.
Note, I'm not really happy with this pull request as-is, see below for
details, but overall this is all good for everything but a small set of
systems, which we have a fix for already.
Lots of tiny driver core changes and cleanups happened this cycle,
but the two major things were:
- firmware_loader reorganization and additions including the
ability to have XZ compressed firmware images and the ability
for userspace to initiate the firmware load when it needs to,
instead of being always initiated by the kernel. FPGA devices
specifically want this ability to have their firmware changed
over the lifetime of the system boot, and this allows them to
work without having to come up with yet-another-custom-uapi
interface for loading firmware for them.
- physical location support added to sysfs so that devices that
know this information, can tell userspace where they are
located in a common way. Some ACPI devices already support
this today, and more bus types should support this in the
future.
Smaller changes included:
- driver_override api cleanups and fixes
- error path cleanups and fixes
- get_abi script fixes
- deferred probe timeout changes.
It's that last change that I'm the most worried about. It has been
reported to cause boot problems for a number of systems, and I have a
tested patch series that resolves this issue. But I didn't get it
merged into my tree before 5.18-final came out, so it has not gotten any
linux-next testing.
I'll send the fixup patches (there are 2) as a follow-on series to this
pull request if you want to take them directly, _OR_ I can just revert
the probe timeout changes and they can wait for the next -rc1 merge
cycle. Given that the fixes are tested, and pretty simple, I'm leaning
toward that choice. Sorry this all came at the end of the merge window,
I should have resolved this all 2 weeks ago, that's my fault as it was
in the middle of some travel for me.
All have been tested in linux-next for weeks, with no reported issues
other than the above-mentioned boot time outs.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
"Here is the set of driver core changes for 5.19-rc1.
Lots of tiny driver core changes and cleanups happened this cycle, but
the two major things are:
- firmware_loader reorganization and additions including the ability
to have XZ compressed firmware images and the ability for userspace
to initiate the firmware load when it needs to, instead of being
always initiated by the kernel. FPGA devices specifically want this
ability to have their firmware changed over the lifetime of the
system boot, and this allows them to work without having to come up
with yet-another-custom-uapi interface for loading firmware for
them.
- physical location support added to sysfs so that devices that know
this information, can tell userspace where they are located in a
common way. Some ACPI devices already support this today, and more
bus types should support this in the future.
Smaller changes include:
- driver_override api cleanups and fixes
- error path cleanups and fixes
- get_abi script fixes
- deferred probe timeout changes.
It's that last change that I'm the most worried about. It has been
reported to cause boot problems for a number of systems, and I have a
tested patch series that resolves this issue. But I didn't get it
merged into my tree before 5.18-final came out, so it has not gotten
any linux-next testing.
I'll send the fixup patches (there are 2) as a follow-on series to this
pull request.
All have been tested in linux-next for weeks, with no reported issues
other than the above-mentioned boot time-outs"
* tag 'driver-core-5.19-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (55 commits)
driver core: fix deadlock in __device_attach
kernfs: Separate kernfs_pr_cont_buf and rename_lock.
topology: Remove unused cpu_cluster_mask()
driver core: Extend deferred probe timeout on driver registration
MAINTAINERS: add Russ Weight as a firmware loader maintainer
driver: base: fix UAF when driver_attach failed
test_firmware: fix end of loop test in upload_read_show()
driver core: location: Add "back" as a possible output for panel
driver core: location: Free struct acpi_pld_info *pld
driver core: Add "*" wildcard support to driver_async_probe cmdline param
driver core: location: Check for allocations failure
arch_topology: Trace the update thermal pressure
kernfs: Rename kernfs_put_open_node to kernfs_unlink_open_file.
export: fix string handling of namespace in EXPORT_SYMBOL_NS
rpmsg: use local 'dev' variable
rpmsg: Fix calling device_lock() on non-initialized device
firmware_loader: describe 'module' parameter of firmware_upload_register()
firmware_loader: Move definitions from sysfs_upload.h to sysfs.h
firmware_loader: Fix configs for sysfs split
selftests: firmware: Add firmware upload selftests
...
The devices on platform/amba/fsl-mc/PCI buses could be bound to drivers
with the device DMA managed by kernel drivers or user-space applications.
Unfortunately, multiple devices may be placed in the same IOMMU group
because they cannot be isolated from each other. The DMA on these devices
must either be entirely under kernel control or userspace control, never
a mixture. Otherwise the driver integrity is not guaranteed because they
could access each other through the peer-to-peer accesses which by-pass
the IOMMU protection.
This checks and sets the default DMA mode during driver binding, and
cleanups during driver unbinding. In the default mode, the device DMA is
managed by the device driver which handles DMA operations through the
kernel DMA APIs (see Documentation/core-api/dma-api.rst).
For cases where the devices are assigned for userspace control through the
userspace driver framework(i.e. VFIO), the drivers(for example, vfio_pci/
vfio_platfrom etc.) may set a new flag (driver_managed_dma) to skip this
default setting in the assumption that the drivers know what they are
doing with the device DMA.
Calling iommu_device_use_default_domain() before {of,acpi}_dma_configure
is currently a problem. As things stand, the IOMMU driver ignored the
initial iommu_probe_device() call when the device was added, since at
that point it had no fwspec yet. In this situation,
{of,acpi}_iommu_configure() are retriggering iommu_probe_device() after
the IOMMU driver has seen the firmware data via .of_xlate to learn that
it actually responsible for the given device. As the result, before
that gets fixed, iommu_use_default_domain() goes at the end, and calls
arch_teardown_dma_ops() if it fails.
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Stuart Yoder <stuyoder@gmail.com>
Cc: Laurentiu Tudor <laurentiu.tudor@nxp.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Link: https://lore.kernel.org/r/20220418005000.897664-5-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Stop sharing platform_dma_configure() helper as they are about to have
their own bus dma_configure callbacks.
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20220418005000.897664-4-baolu.lu@linux.intel.com
Signed-off-by: Joerg Roedel <jroedel@suse.de>
The commit a85a6c86c2 ("driver core: platform: Clarify that IRQ 0 is
invalid") only calls WARN() when IRQ0 is about to be returned, however
using IRQ0 is considered invalid (according to Linus) outside the arch/
code where it's used by the i8253 drivers. Many driver subsystems treat
0 specially (e.g. as an indication of the polling mode by libata), so
the users of platform_get_irq[_byname]() in them would have to filter
out IRQ0 explicitly and this (quite obviously) doesn't scale...
Let's finally get this straight and return -EINVAL instead of IRQ0!
Fixes: a85a6c86c2 ("driver core: platform: Clarify that IRQ 0 is invalid")
Acked-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Link: https://lore.kernel.org/r/025679e1-1f0a-ae4b-4369-01164f691511@omp.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Several core drivers and buses expect that driver_override is a
dynamically allocated memory thus later they can kfree() it.
However such assumption is not documented, there were in the past and
there are already users setting it to a string literal. This leads to
kfree() of static memory during device release (e.g. in error paths or
during unbind):
kernel BUG at ../mm/slub.c:3960!
Internal error: Oops - BUG: 0 [#1] PREEMPT SMP ARM
...
(kfree) from [<c058da50>] (platform_device_release+0x88/0xb4)
(platform_device_release) from [<c0585be0>] (device_release+0x2c/0x90)
(device_release) from [<c0a69050>] (kobject_put+0xec/0x20c)
(kobject_put) from [<c0f2f120>] (exynos5_clk_probe+0x154/0x18c)
(exynos5_clk_probe) from [<c058de70>] (platform_drv_probe+0x6c/0xa4)
(platform_drv_probe) from [<c058b7ac>] (really_probe+0x280/0x414)
(really_probe) from [<c058baf4>] (driver_probe_device+0x78/0x1c4)
(driver_probe_device) from [<c0589854>] (bus_for_each_drv+0x74/0xb8)
(bus_for_each_drv) from [<c058b48c>] (__device_attach+0xd4/0x16c)
(__device_attach) from [<c058a638>] (bus_probe_device+0x88/0x90)
(bus_probe_device) from [<c05871fc>] (device_add+0x3dc/0x62c)
(device_add) from [<c075ff10>] (of_platform_device_create_pdata+0x94/0xbc)
(of_platform_device_create_pdata) from [<c07600ec>] (of_platform_bus_create+0x1a8/0x4fc)
(of_platform_bus_create) from [<c0760150>] (of_platform_bus_create+0x20c/0x4fc)
(of_platform_bus_create) from [<c07605f0>] (of_platform_populate+0x84/0x118)
(of_platform_populate) from [<c0f3c964>] (of_platform_default_populate_init+0xa0/0xb8)
(of_platform_default_populate_init) from [<c01031f8>] (do_one_initcall+0x8c/0x404)
Provide a helper which clearly documents the usage of driver_override.
This will allow later to reuse the helper and reduce the amount of
duplicated code.
Convert the platform driver to use a new helper and make the
driver_override field const char (it is not modified by the core).
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220419113435.246203-2-krzysztof.kozlowski@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The commit 2043727c28 ("driver core: platform: Make use of the helper
function dev_err_probe()") missed to also convert platform_get_irq_byname()
for some strange reason -- do that now.
Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Link: https://lore.kernel.org/r/11a4aeb2-721c-56a9-919b-f356a30720e0@omp.ru
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add an explicit comment to document that the reference initialised by
platform_device_register() needs to be released by a call to
platform_device_put() also when registration fails (cf.
device_register()).
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20211222104213.5673-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When possible using dev_err_probe() helps to properly deal with the
PROBE_DEFER error, the benefit is that DEFER issue will be logged
in the devices_deferred debugfs file.
Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
Link: https://lore.kernel.org/r/20211105071509.969-1-caihuoqing@baidu.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use the helper macro SET_RUNTIME_PM_OPS() instead of the verbose
operators ".runtime_suspend/.runtime_resume", because the
SET_RUNTIME_PM_OPS() is a nice helper macro that could be brought
in to make code a little clearer, a little more concise.
Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
Link: https://lore.kernel.org/r/20210828090219.1177-1-caihuoqing@baidu.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are no more users for it. The last place where it's
called is in platform_device_register_full(). Replacing that
call with device_create_managed_software_node() and
removing the function.
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Link: https://lore.kernel.org/r/20210817102449.39994-3-heikki.krogerus@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The driver core ignores the return value of this callback because there
is only little it can do when a device disappears.
This is the final bit of a long lasting cleanup quest where several
buses were converted to also return void from their remove callback.
Additionally some resource leaks were fixed that were caused by drivers
returning an error code in the expectation that the driver won't go
away.
With struct bus_type::remove returning void it's prevented that newly
implemented buses return an ignored error code and so don't anticipate
wrong expectations for driver authors.
Reviewed-by: Tom Rix <trix@redhat.com> (For fpga)
Reviewed-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Cornelia Huck <cohuck@redhat.com> (For drivers/s390 and drivers/vfio)
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> (For ARM, Amba and related parts)
Acked-by: Mark Brown <broonie@kernel.org>
Acked-by: Chen-Yu Tsai <wens@csie.org> (for sunxi-rsb)
Acked-by: Pali Rohár <pali@kernel.org>
Acked-by: Mauro Carvalho Chehab <mchehab@kernel.org> (for media)
Acked-by: Hans de Goede <hdegoede@redhat.com> (For drivers/platform)
Acked-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Acked-By: Vinod Koul <vkoul@kernel.org>
Acked-by: Juergen Gross <jgross@suse.com> (For xen)
Acked-by: Lee Jones <lee.jones@linaro.org> (For mfd)
Acked-by: Johannes Thumshirn <jth@kernel.org> (For mcb)
Acked-by: Johan Hovold <johan@kernel.org>
Acked-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> (For slimbus)
Acked-by: Kirti Wankhede <kwankhede@nvidia.com> (For vfio)
Acked-by: Maximilian Luz <luzmaximilian@gmail.com>
Acked-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> (For ulpi and typec)
Acked-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com> (For ipack)
Acked-by: Geoff Levand <geoff@infradead.org> (For ps3)
Acked-by: Yehezkel Bernat <YehezkelShB@gmail.com> (For thunderbolt)
Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> (For intel_th)
Acked-by: Dominik Brodowski <linux@dominikbrodowski.net> (For pcmcia)
Acked-by: Rafael J. Wysocki <rafael@kernel.org> (For ACPI)
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org> (rpmsg and apr)
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> (For intel-ish-hid)
Acked-by: Dan Williams <dan.j.williams@intel.com> (For CXL, DAX, and NVDIMM)
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com> (For isa)
Acked-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (For firewire)
Acked-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> (For hid)
Acked-by: Thorsten Scherer <t.scherer@eckelmann.de> (For siox)
Acked-by: Sven Van Asbroeck <TheSven73@gmail.com> (For anybuss)
Acked-by: Ulf Hansson <ulf.hansson@linaro.org> (For MMC)
Acked-by: Wolfram Sang <wsa@kernel.org> # for I2C
Acked-by: Sudeep Holla <sudeep.holla@arm.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Finn Thain <fthain@linux-m68k.org>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20210713193522.1770306-6-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
These are only used by putting their address in an array of pointers to
const struct attribute_group (either directly or via the
__ATTRIBUTE_GROUP macro). Make them const to allow the compiler to place
them in read-only memory.
Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Link: https://lore.kernel.org/r/20210528213408.20067-1-rikard.falkeborn@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Since the macro was introduced in 2019 (commit bb6243b4f7 ("drivers:
platform: provide devm_platform_ioremap_resource_wc()") there is only a
single user which hardly justifies the function for the small task it
provides.
So drop the helper and open-code it in the only user. Adapt the non-wc
case accordingly.
For a all-mod-config build on amd64 this change introduces the following
changes according to bloat-o-meter:
add/remove: 0/1 grow/shrink: 1/0 up/down: 20/-252 (-232)
Function old new delta
devm_platform_ioremap_resource_wc 252 - -252
sram_probe 796 816 +20
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20210525103711.956438-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently the platform_get_irq_optional() returns an error code even
if IRQ resource sumply has not been found. It prevents caller to be
error code agnostic in their error handling.
Now:
ret = platform_get_irq_optional(...);
if (ret != -ENXIO)
return ret; // respect deferred probe
if (ret > 0)
...we get an IRQ...
After proposed change:
ret = platform_get_irq_optional(...);
if (ret < 0)
return ret;
if (ret > 0)
...we get an IRQ...
Reported-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210331144526.19439-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We have few code paths where same error code is assigned and
returned for missed IRQ. Unify that under single error path.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20210331145937.35980-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Here is the "big" driver core and debugfs update for 5.12-rc1
This set of driver core patches caused a bunch of problems in linux-next
for the past few weeks, when Saravana tried to set fw_devlink=on as the
default functionality. This caused a number of systems to stop booting,
and lots of bugs were fixed in this area for almost all of the reported
systems, but this option is not ready to be turned on just yet for the
default operation based on this testing, so I've reverted that change at
the very end so we don't have to worry about regressions in 5.12. We
will try to turn this on for 5.13 if testing goes better over the next
few months.
Other than the fixes caused by the fw_devlink testing in here, there's
not much more:
- debugfs fixes for invalid input into debugfs_lookup()
- kerneldoc cleanups
- warn message if platform drivers return an error on their
remove callback (a futile effort, but good to catch).
All of these have been in linux-next for a while now, and the
regressions have gone away with the revert of the fw_devlink change.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'driver-core-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core / debugfs update from Greg KH:
"Here is the "big" driver core and debugfs update for 5.12-rc1
This set of driver core patches caused a bunch of problems in
linux-next for the past few weeks, when Saravana tried to set
fw_devlink=on as the default functionality. This caused a number of
systems to stop booting, and lots of bugs were fixed in this area for
almost all of the reported systems, but this option is not ready to be
turned on just yet for the default operation based on this testing, so
I've reverted that change at the very end so we don't have to worry
about regressions in 5.12
We will try to turn this on for 5.13 if testing goes better over the
next few months.
Other than the fixes caused by the fw_devlink testing in here, there's
not much more:
- debugfs fixes for invalid input into debugfs_lookup()
- kerneldoc cleanups
- warn message if platform drivers return an error on their remove
callback (a futile effort, but good to catch).
All of these have been in linux-next for a while now, and the
regressions have gone away with the revert of the fw_devlink change"
* tag 'driver-core-5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (35 commits)
Revert "driver core: Set fw_devlink=on by default"
of: property: fw_devlink: Ignore interrupts property for some configs
debugfs: do not attempt to create a new file before the filesystem is initalized
debugfs: be more robust at handling improper input in debugfs_lookup()
driver core: auxiliary bus: Fix calling stage for auxiliary bus init
of: irq: Fix the return value for of_irq_parse_one() stub
of: irq: make a stub for of_irq_parse_one()
clk: Mark fwnodes when their clock provider is added/removed
PM: domains: Mark fwnodes when their powerdomain is added/removed
irqdomain: Mark fwnodes when their irqdomain is added/removed
driver core: fw_devlink: Handle suppliers that don't use driver core
of: property: Add fw_devlink support for optional properties
driver core: Add fw_devlink.strict kernel param
of: property: Don't add links to absent suppliers
driver core: fw_devlink: Detect supplier devices that will never be added
driver core: platform: Emit a warning if a remove callback returned non-zero
of: property: Fix fw_devlink handling of interrupts/interrupts-extended
gpiolib: Don't probe gpio_device if it's not the primary device
device.h: Remove bogus "the" in kerneldoc
gpiolib: Bind gpio_device to a driver to enable fw_devlink=on by default
...
- Sync dtc to upstream version v1.6.0-51-g183df9e9c2b9 and build
host fdtoverlay
- Add kbuild support to build DT overlays (%.dtbo)
- Drop NULLifying match table in of_match_device(). In preparation for
this, there are several driver cleanups to use
(of_)?device_get_match_data().
- Drop pointless wrappers from DT struct device API
- Convert USB binding schemas to use graph schema and remove old plain
text graph binding doc
- Convert spi-nor and v3d GPU bindings to DT schema
- Tree wide schema fixes for if/then schemas, array size constraints,
and undocumented compatible strings in examples
- Handle 'no-map' correctly for already reserved memblock regions
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Merge tag 'devicetree-for-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux
Pull devicetree updates from Rob Herring:
- Sync dtc to upstream version v1.6.0-51-g183df9e9c2b9 and build host
fdtoverlay
- Add kbuild support to build DT overlays (%.dtbo)
- Drop NULLifying match table in of_match_device().
In preparation for this, there are several driver cleanups to use
(of_)?device_get_match_data().
- Drop pointless wrappers from DT struct device API
- Convert USB binding schemas to use graph schema and remove old plain
text graph binding doc
- Convert spi-nor and v3d GPU bindings to DT schema
- Tree wide schema fixes for if/then schemas, array size constraints,
and undocumented compatible strings in examples
- Handle 'no-map' correctly for already reserved memblock regions
* tag 'devicetree-for-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux: (35 commits)
driver core: platform: Drop of_device_node_put() wrapper
of: Remove of_dev_{get,put}()
dt-bindings: usb: Change descibe to describe in usbmisc-imx.txt
dt-bindings: can: rcar_canfd: Group tuples in pin control properties
dt-bindings: power: renesas,apmu: Group tuples in cpus properties
dt-bindings: mtd: spi-nor: Convert to DT schema format
dt-bindings: Use portable sort for version cmp
dt-bindings: ethernet-controller: fix fixed-link specification
dt-bindings: irqchip: Add node name to PRUSS INTC
dt-bindings: interconnect: Fix the expected number of cells
dt-bindings: Fix errors in 'if' schemas
dt-bindings: iommu: renesas,ipmmu-vmsa: Make 'power-domains' conditionally required
dt-bindings: Fix undocumented compatible strings in examples
kbuild: Add support to build overlays (%.dtbo)
scripts: dtc: Remove the unused fdtdump.c file
scripts: dtc: Build fdtoverlay tool
scripts/dtc: Update to upstream version v1.6.0-51-g183df9e9c2b9
scripts: dtc: Fetch fdtoverlay.c from external DTC project
dt-bindings: thermal: sun8i: Fix misplaced schema keyword in compatible strings
dt-bindings: iio: dac: Fix AD5686 references
...
of_device_node_put() is just a wrapper for of_node_put(). The platform
driver core is already polluted with of_node pointers and the only 'get'
already uses of_node_get() (though typically the get would happen in
of_device_alloc()).
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20210211232745.1498137-3-robh@kernel.org
The driver core ignores the return value of a bus' remove callback. However
a driver returning an error code is a hint that there is a problem,
probably a driver author who expects that returning e.g. -EBUSY has any
effect.
The right thing to do would be to make struct platform_driver::remove()
return void. With the immense number of platform drivers this is however a
big quest and I hope to prevent at least a few new drivers that return an
error code here.
Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org>
Link: https://lore.kernel.org/r/20210207211537.19992-1-uwe@kleine-koenig.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The current check of nvec < minvec for nvec returned from
platform_irq_count() will not detect a negative error code in nvec.
This is because minvec is unsigned, and, as such, nvec is promoted to
unsigned in that check, which will make it a huge number (if it contained
-EPROBE_DEFER).
In practice, an error should not occur in nvec for the only in-tree
user, but add a check anyway.
Fixes: e15f2fa959 ("driver core: platform: Add devm_platform_get_irqs_affinity()")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/1608561055-231244-1-git-send-email-john.garry@huawei.com
Core:
- Consolidation and robustness changes for irq time accounting
- Cleanup and consolidation of irq stats
- Remove the fasteoi IPI flow which has been proved useless
- Provide an interface for converting legacy interrupt mechanism into
irqdomains
Drivers:
The rare event of not having completely new chip driver code, just new
DT bindings and extensions of existing drivers to accomodate new
variants!
- Preliminary support for managed interrupts on platform devices
- Correctly identify allocation of MSIs proxyied by another device
- Generalise the Ocelot support to new SoCs
- Improve GICv4.1 vcpu entry, matching the corresponding KVM optimisation
- Work around spurious interrupts on Qualcomm PDC
- Random fixes and cleanups
Thanks,
tglx
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Merge tag 'irq-core-2020-12-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq updates from Thomas Gleixner:
"Generic interrupt and irqchips subsystem updates. Unusually, there is
not a single completely new irq chip driver, just new DT bindings and
extensions of existing drivers to accomodate new variants!
Core:
- Consolidation and robustness changes for irq time accounting
- Cleanup and consolidation of irq stats
- Remove the fasteoi IPI flow which has been proved useless
- Provide an interface for converting legacy interrupt mechanism into
irqdomains
Drivers:
- Preliminary support for managed interrupts on platform devices
- Correctly identify allocation of MSIs proxyied by another device
- Generalise the Ocelot support to new SoCs
- Improve GICv4.1 vcpu entry, matching the corresponding KVM
optimisation
- Work around spurious interrupts on Qualcomm PDC
- Random fixes and cleanups"
* tag 'irq-core-2020-12-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits)
irqchip/qcom-pdc: Fix phantom irq when changing between rising/falling
driver core: platform: Add devm_platform_get_irqs_affinity()
ACPI: Drop acpi_dev_irqresource_disabled()
resource: Add irqresource_disabled()
genirq/affinity: Add irq_update_affinity_desc()
irqchip/gic-v3-its: Flag device allocation as proxied if behind a PCI bridge
irqchip/gic-v3-its: Tag ITS device as shared if allocating for a proxy device
platform-msi: Track shared domain allocation
irqchip/ti-sci-intr: Fix freeing of irqs
irqchip/ti-sci-inta: Fix printing of inta id on probe success
drivers/irqchip: Remove EZChip NPS interrupt controller
Revert "genirq: Add fasteoi IPI flow"
irqchip/hip04: Make IPIs use handle_percpu_devid_irq()
irqchip/bcm2836: Make IPIs use handle_percpu_devid_irq()
irqchip/armada-370-xp: Make IPIs use handle_percpu_devid_irq()
irqchip/gic, gic-v3: Make SGIs use handle_percpu_devid_irq()
irqchip/ocelot: Add support for Jaguar2 platforms
irqchip/ocelot: Add support for Serval platforms
irqchip/ocelot: Add support for Luton platforms
irqchip/ocelot: prepare to support more SoC
...
On shutdown the driver core calls the bus' shutdown callback also for
unbound devices. A driver's shutdown callback however is only called for
devices bound to this driver. Commit 9c30921fe7 ("driver core:
platform: use bus_type functions") changed the platform bus from driver
callbacks to bus callbacks, so the shutdown function must be prepared to
be called without a driver. Add the corresponding check in the shutdown
function.
Fixes: 9c30921fe7 ("driver core: platform: use bus_type functions")
Tested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20201212235533.247537-1-dmitry.baryshkov@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Drivers for multi-queue platform devices may also want managed interrupts
for handling HW queue completion interrupts, so add support.
The function accepts an affinity descriptor pointer, which covers all IRQs
expected for the device.
The function is devm class as the only current in-tree user will also use
devm method for requesting the interrupts; as such, the function is made
as devm as it can ensure ordering of freeing the irq and disposing of the
mapping.
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/1606905417-183214-5-git-send-email-john.garry@huawei.com
There are at least few existing users of the proposed API which
retrieves either MEM or IO resource from platform device.
Make it common to utilize in the existing and new users.
Cc: Eric Auger <eric.auger@redhat.com>
Cc: Alex Williamson <alex.williamson@redhat.com>
Cc: kvm@vger.kernel.org
Cc: linux-usb@vger.kernel.org
Cc: Peng Hao <peng.hao2@zte.com.cn>
Cc: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20201209203642.27648-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This works towards the goal mentioned in 2006 in commit 594c8281f9
("[PATCH] Add bus_type probe, remove, shutdown methods.").
The functions are moved to where the other bus_type functions are
defined and renamed to match the already established naming scheme.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20201119124611.2573057-3-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Instead of overwriting the core driver's probe function handle probing
devices for drivers loaded by platform_driver_probe() in the platform
driver probe function.
The intended goal is to not have to change the probe function to
simplify converting the platform bus to use bus functions.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20201119124611.2573057-2-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This way all callbacks and structures used to initialize
platform_bus_type are defined just before platform_bus_type and in the
same order. Also move platform_drv_probe_fail just before it's only
user.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20201119124611.2573057-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Change additional instances that could use sysfs_emit and sysfs_emit_at
that the coccinelle script could not convert.
o macros creating show functions with ## concatenation
o unbound sprintf uses with buf+len for start of output to sysfs_emit_at
o returns with ?: tests and sprintf to sysfs_emit
o sysfs output with struct class * not struct device * arguments
Miscellanea:
o remove unnecessary initializations around these changes
o consistently use int len for return length of show functions
o use octal permissions and not S_<FOO>
o rename a few show function names so DEVICE_ATTR_<FOO> can be used
o use DEVICE_ATTR_ADMIN_RO where appropriate
o consistently use const char *output for strings
o checkpatch/style neatening
Signed-off-by: Joe Perches <joe@perches.com>
Link: https://lore.kernel.org/r/8bc24444fe2049a9b2de6127389b57edfdfe324d.1600285923.git.joe@perches.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We don't need to specify any ranges when allocating IDs so we can switch
to ida_alloc() and ida_free() instead of the ida_simple_ counterparts.
ida_simple_get(ida, 0, 0, gfp) is equivalent to
ida_alloc_range(ida, 0, UINT_MAX, gfp) which is equivalent to
ida_alloc(ida, gfp). Note: IDR will never actually allocate an ID
larger than INT_MAX.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Link: https://lore.kernel.org/r/20200909180248.10093-1-brgl@bgdev.pl
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
I can't always remember the return values of these functions, and so I
usually jump to the function to read the kernel-doc and see that it
doesn't tell me. Then I have to spend more time reading the code to jump
to the function that actually tells me the return values. Let's document
it here so that we don't all have to spend time digging through the code
to understand the return values.
Cc: <linux-doc@vger.kernel.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20200910060440.2302925-1-swboyd@chromium.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
