The gpio-mockup driver creates the properties that are shared between
platform and GPIO devices. Because of that, the properties may not
be removed at the proper point of time without provoking a use-after-free
as shown in the following backtrace:
refcount_t: underflow; use-after-free.
WARNING: CPU: 0 PID: 103 at lib/refcount.c:28 refcount_warn_saturate+0xd1/0x120
...
Call Trace:
kobject_put+0xdc/0xf0
software_node_notify_remove+0xa8/0xc0
device_del+0x15a/0x3e0
That's why the driver has to manage the lifetime of the software nodes
by itself.
The problem originates from the old device_add_properties() API, but
has been only revealed after the commit bd1e336aa8 ("driver core: platform:
Remove platform_device_add_properties()"). Hence, it's used as a landmark
for backporting.
Fixes: bd1e336aa8 ("driver core: platform: Remove platform_device_add_properties()")
Reported-by: Kent Gibson <warthog618@gmail.com>
Tested-by: Kent Gibson <warthog618@gmail.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
[Bartosz: tweaked local variable placement]
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Switch to use gpiochip_get_desc() helper.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Since platform_device_unregister() is NULL-aware, we don't need to duplicate
this check. Remove it and fold the rest of the code.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Allow the mockup driver to be probed via the device tree without any
module parameters, allowing it to be used to configure and test higher
level drivers like the leds-gpio driver and corresponding userspace
before actual hardware is available.
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Let's move the code preparing the device properties into a separate
routine. This has the advantage of simplifying the error handling and
makes the indentation less deep.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
GPIO line names are currently created by the driver from the chip label.
We'll want to support custom formats for line names (for instance: to
name all lines the same) for user-space tests so create them in the
module init function and pass them to the driver using the standard
'gpio-line-names' property.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
While we do check the "chip-name" property in probe(), we never actually
use it. Let's pass the chip label to the driver using device properties
as we'll want to allow users to define their own once dynamically
created chips are supported.
The property is renamed to "chip-label" to not cause any confusion with
the actual chip name which is of the form: "gpiochipX".
If the "chip-label" property is missing, let's do what most devices in
drivers/gpio/ do and use dev_name().
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
The driver actually supports 4 properties but we only ever set up up to
three. This will change however in upcoming patches so increase the
number of really (as in: the number the property array can hold)
supported properties to 4.
Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
There's a return; at the end of a void function. This is not needed so
remove it.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
We don't need a custom logging helper. Let's use the standard pr_fmt()
macro which allows us to use all pr_*() routines with custom format.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Drop the definition for the driver name. Let's use KBUILD_MODNAME for
the log format and use the "gpio-mockup" value directly in the only
place where it's relevant: in the name of the device.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
This module doesn't need gpio/consumer.h - it's a provider. It also
doesn't use any symbols from init.h so let's remove both includes.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
If the module init function fails after creating the debugs directory,
it's never removed. Add proper cleanup calls to avoid this resource
leak.
Fixes: 9202ba2397 ("gpio: mockup: implement event injecting over debugfs")
Cc: <stable@vger.kernel.org>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
The interrupt simulator API exposes a lot of custom data structures and
functions and doesn't reuse the interfaces already exposed by the irq
subsystem. This patch tries to address it.
We hide all the simulator-related data structures from users and instead
rely on the well-known irq domain. When creating the interrupt simulator
the user receives a pointer to a newly created irq_domain and can use it
to create mappings for simulated interrupts.
It is also possible to pass a handle to fwnode when creating the simulator
domain and retrieve it using irq_find_matching_fwnode().
The irq_sim_fire() function is dropped as well. Instead we implement the
irq_get/set_irqchip_state interface.
We modify the two modules that use the simulator at the same time as
adding these changes in order to reduce the intermediate bloat that would
result when trying to migrate the drivers in separate patches.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> #for IIO
Link: https://lore.kernel.org/r/20200514083901.23445-3-brgl@bgdev.pl
The indentation is wrong in gpio_mockup_apply_pull(). This patch makes
the code more readable.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Link: https://lore.kernel.org/r/20200210155059.29609-1-brgl@bgdev.pl
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
I have missed two indentation issues in commit 64e7112ee3 ("gpio:
mockup: add set_config to support pull up/down"). This commit fixes them.
Fixes: 64e7112ee3 ("gpio: mockup: add set_config to support pull up/down")
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Restore the external behavior of gpio-mockup to what it was prior to the
change to using GPIO_LINE_DIRECTION.
Fixes: e42615ec23 ("gpio: Use new GPIO_LINE_DIRECTION")
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Add support for the pull up/down state set via gpiolib line requests to
be reflected in the state of the mockup.
Use case is for testing of the GPIO uAPI, specifically the pull up/down
flags.
Signed-off-by: Kent Gibson <warthog618@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
It's hard for occasional GPIO code reader/writer to know if values 0/1
equal to IN or OUT. Use defined GPIO_LINE_DIRECTION_IN and
GPIO_LINE_DIRECTION_OUT to help them out.
NOTE - for gpio-amd-fch and gpio-bd9571mwv:
This commit also changes the return value for direction get to equal 1
for direction INPUT. Prior this commit these drivers might have
returned some other positive value but 1 for INPUT.
Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Acked-by: Scott Branden <scott.branden@broadcom.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Reviewed-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Acked-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
When using single_open() for opening, single_release() should be
used instead of seq_release(), otherwise there is a memory leak.
Fixes: 2a9e27408e ("gpio: mockup: rework debugfs interface")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.
Cc: Bamvor Jian Zhang <bamv2005@gmail.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Cc: linux-gpio@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[Bartosz: removed one more check for debugfs return value]
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Calling read() for a single byte read will return 2 currently. Use
simple_read_from_buffer() which correctly handles all sizes.
Fixes: 2a9e27408e ("gpio: mockup: rework debugfs interface")
Reviewed-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
The debugfs read callback must advance ppos or users using read() on
the file descriptor will never get the EOL. This wasn't spotted before
as I was using busybox cat for testing which uses sendfile() internally
and only noticed it now when switched to cat from coreutils.
Fixes: 2a9e27408e ("gpio: mockup: rework debugfs interface")
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Modify the way the debugfs interface works in gpio-mockup. Introduce
the concept of dummy pull config which will keep the mockup lines in
known state. The pull values can be modified by writing to the debugfs
files corresponding to lines. Lines in input mode always report the
current pull value, lines in output mode change the line value but
it will revert back to the one specified by current pull when released.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
The unlocked variants only get called from places where we already have
the pointer to the underlying gpio_mockup_chip structure, so take it
as parameter instead of struct gpio_chip.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
While no user reported any race condition problems with gpio-mockup,
let's be on the safe side and use a mutex when performing any changes
on the dummy chip structures.
Suggested-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Commit 3edfb7bd76 ("gpiolib: Show correct direction from the
beginning") fixed an existing issue but broke libgpiod tests by
changing the default direction of dummy lines to output.
We don't break user-space so make gpio-mockup behave as before.
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Some users want to introduce device tree support to the mockup driver.
Let's make it easier by switching to using generic device properties.
The driver stays compatible with previous use cases and after this
conversion there'll be no need to change the way probing of mockup
GPIO chips works.
Tested with libgpiod test suite.
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Use the SPDX license identifier for GPLv2.0 or later and remove the
license boilerplate.
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
If we failed to create the top debugfs directory, we must not try to
create the child nodes. We currently only check if gpio_mockup_dbg_dir
is not NULL, but it can also contain an errno if debugfs is disabled
in build options. Use IS_ERR_OR_NULL() instead.
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Bamvor changed his mail so let's updat his mail address
everywhere.
Cc: Bamvor Jian Zhang <bamv2005@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The return value of platform_device_register_resndata() on error is
an error code converted to pointer with ERR_PTR(), not NULL.
Check the return value correctly.
Fixes: 8a39f597bc ("gpio: mockup: rework device probing")
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
In order to avoid repeating the calculations on every access - add
helpers for gpio base and ngpio components of the ranges array.
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This variable holds the number of mockup GPIO ranges so rename it
accordingly.
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
As discussed with Marc Zyngier: irq_sim_init() and its devres variant
should return the base of the allocated interrupt range on success
rather than 0. This will be modified later - first, change the way
users handle the return value of these routines.
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Implement the set_multiple() callback and register it with the gpiolib
framework. This is only meant to also test the internal kernel API.
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Minor readability tweak: prefer breaking the lines in a way where the
second part is longer than the first.
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Improve the module params sanitization: bail out from init if the user
tries to pass a non-positive number of GPIO lines for any mockup chip.
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The debugfs routines returning pointers can return NULL or error codes
embedded with ERR_PTR(). Check the return values with IS_ERR_OR_NULL().
While we're at it: make the error message more specific so it's not
confused with the one emitted when the top-level gpio-mockup debugfs
directory creation fails.
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Keep GPIO chip callbacks, event trigger callbacks and mockup chip
setup code visibly separated. We're mostly good - just need to move
the line naming routine below.
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
GPIO values are universally represented as integers. Change the type
of the variable storing the current line value to int for consistency.
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Currently each chip has a dedicated directory in debugfs for event
triggers. We use the chip's label for the directory name, but the user
can't really associate these directories with chip names without
parsing the relevant sysfs entries.
Use chip names for directory names. For backward compatibility: create
links pointing to the actual directories named using the chip labels.
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Move the last bits of code dealing with module parameters to the init
function. Add a new variable to platform data, which indicates to the
probe function if it should name the GPIO lines. If we ever want to
make the line naming more fine-grained (e.g. per chip switch) it will
be easier this way.
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Now that the probe() function only does what is should, there's no
need to split the chip adding logic into a separate routine. Merge
gpio_mockup_add() into gpio_mockup_probe().
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Andy Shevchenko