This option was added in 6a89a314 to
allow use of the devm_gpio_* functions without CONFIG_GPIOLIB.

However, only a few months later in
b69ac524, CONFIG_GPIOLIB was added
as a dependency, defeating the original purpose of this option.
Instead of that patch, the original commit could have just been
reverted (and in fact was partially so in
403c1d0b). Further, since this
option has a dependency on HAS_IOMEM, even though it does not
require it, it causes build failures when !HAS_IOMEM (e.g. in a
uml build).

Fix that by completely removing the option, in essence completing
the reversion of the original commit.
Signed-off-by: NKeno Fischer <keno@juliacomputing.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The bit in the TC3589x direction register is 0 for input
and 1 for output, but the gpiolib expects the reverse.
Fix up the logic.

Cc: stable@vger.kernel.org
Fixes: 14063d71 ("gpio: tc3589x: add .get_direction() and small cleanup")
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

When locking a GPIO line as IRQ, we go to lengths to
double-check that the line is really set as input before
marking it as used for IRQ. This is not good on GPIO chips
that can sleep, because this function is called in IRQ-safe
context. Just skip this if it can't be checked quickly.

Currently this happens on sleeping expanders such as STMPE
or TC3589x:

BUG: scheduling while atomic: swapper/1/0x00000002
Modules linked in:
CPU: 0 PID: 1 Comm: swapper Not tainted 4.9.0-rc1+ #38
Hardware name: Nomadik STn8815
[<c000f2e0>] (unwind_backtrace) from [<c000d244>] (show_stack+0x10/0x14)
[<c000d244>] (show_stack) from [<c0037b78>] (__schedule_bug+0x54/0x80)
[<c0037b78>] (__schedule_bug) from [<c042df14>] (__schedule+0x3a0/0x460)
[<c042df14>] (__schedule) from [<c042e028>] (schedule+0x54/0xb8)
(...)

This patch fixes that problem and relies on the direction
read from the chip when it was added.

Cc: stable@vger.kernel.org
Fixes: 9c10280d ("gpio: flush direction status in gpiochip_lock_as_irq()")
Cc: Patrice Chotard <patrice.chotard@st.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Need to ensure that reg_output is not updated while setting multiple
bits. This makes the mutex locking behaviour for the set_multiple call
consistent with that of the set_value call.

Cc: stable@vger.kernel.org
Fixes: b4818afe ("gpio: pca953x: Add set_multiple to allow multiple")
Signed-off-by: NPhil Reid <preid@electromag.com.au>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

gpiod_set_array_value_complex does not clear the bits field.
Therefore when the drivers set_multiple funciton is called bits outside
the mask are undefined and can be either set or not. So bank_val needs
to be masked with bank_mask before or with the reg_val cache.

Cc: stable@vger.kernel.org
Fixes: b4818afe ("gpio: pca953x: Add set_multiple to allow multiple")
Signed-off-by: NPhil Reid <preid@electromag.com.au>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This fixes the irq allocation in this driver to not print:
 irq: Cannot allocate irq_descs @ IRQ34, assuming pre-allocated
 irq: Cannot allocate irq_descs @ IRQ66, assuming pre-allocated

Which happens because the driver already called irq_alloc_descs()
and so the change to use irq_domain_add_simple resulted in calling
irq_alloc_descs() twice.

Modernize the irq allocation in this driver to use the
irq_domain_add_linear flow directly and eliminate the use of
irq_domain_add_simple/legacy

Fixes: ce931f57 ("gpio/mvebu: convert to use irq_domain_add_simple()")
Signed-off-by: NJason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Sylvain Lemieux reports the LPC32xx GPIO driver is broken since
commit 762c2e46 ("gpio: of: remove of_gpiochip_and_xlate() and
struct gg_data").  Probably, gpio-etraxfs.c and gpio-davinci.c are
broken too.

Those drivers register multiple gpio_chip that are associated to a
single OF node, and their own .of_xlate() checks if the passed
gpio_chip is valid.

Now, the problem is of_find_gpiochip_by_node() returns the first
gpio_chip found to match the given node.  So, .of_xlate() fails,
except for the first GPIO bank.

Reverting the commit could be a solution, but I do not want to go
back to the mess of struct gg_data.  Another solution here is to
take the match by a node pointer and the success of .of_xlate().
It is a bit clumsy to call .of_xlate twice; for gpio_chip matching
and for really getting the gpio_desc index.  Perhaps, our long-term
goal might be to convert the drivers to single chip registration,
but this commit will solve the problem until then.

Fixes: 762c2e46 ("gpio: of: remove of_gpiochip_and_xlate() and struct gg_data")
Signed-off-by: NMasahiro Yamada <yamada.masahiro@socionext.com>
Reported-by: NSylvain Lemieux <slemieux.tyco@gmail.com>
Tested-by: NDavid Lechner <david@lechnology.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

When allocating a new line handle or event a file is allocated that it is
associated to. The file is attached to a file descriptor of the current
process and the file descriptor is returned to userspace using
copy_to_user(). If this copy operation fails the line handle or event
allocation is aborted, all acquired resources are freed and an error is
returned.

But the file struct is not freed and left attached to the userspace
application and even though the file descriptor number was not copied it is
trivial to guess. If a userspace application performs a IOCTL on such a
left over file descriptor it will trigger a use-after-free and if the file
descriptor is closed (latest when the application exits) a double-free is
triggered.

anon_inode_getfd() performs 3 tasks, allocate a file struct, allocate a
file descriptor for the current process and install the file struct in the
file descriptor. As soon as the file struct is installed in the file
descriptor it is accessible by userspace (even if the IOCTL itself hasn't
completed yet), this means uninstalling the fd on the error path is not an
option, since userspace might already got a reference to the file.

Instead anon_inode_getfd() needs to be broken into its individual steps.
The allocation of the file struct and file descriptor is done first, then
the copy_to_user() is executed and only if it succeeds the file is
installed.

Since the file struct is reference counted it can not be just freed, but
its reference needs to be dropped, which will also call the release()
callback, which will free the state attached to the file. So in this case
the normal error cleanup path should not be taken.

Cc: stable@vger.kernel.org
Fixes: d932cd49 ("gpio: free handles in fringe cases")
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

From the beginning of the gpio-mpc8xxx.c, the "handle_level_irq"
has being used to handle GPIO interrupts in the PowerPC/Layerscape
platforms. But actually, almost all PowerPC/Layerscape platforms
assert an interrupt request upon either a high-to-low change or
any change on the state of the signal.

So the "handle_level_irq" is not reasonable for PowerPC/Layerscape
GPIO interrupt, it should be "handle_edge_irq". Otherwise the system
may lost some interrupts from the PIN's state changes.
Signed-off-by: NLiu Gang <Gang.Liu@nxp.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

If the driver is built as a module, autoload won't work because the module
alias information is not filled. So user-space can't match the registered
device with the corresponding module.

Export the module alias information using the MODULE_DEVICE_TABLE() macro.

Before this patch:

$ modinfo drivers/gpio/gpio-ath79.ko | grep alias
$

After this patch:

$ modinfo drivers/gpio/gpio-ath79.ko | grep alias
alias:          of:N*T*Cqca,ar9340-gpioC*
alias:          of:N*T*Cqca,ar9340-gpio
alias:          of:N*T*Cqca,ar7100-gpioC*
alias:          of:N*T*Cqca,ar7100-gpio
Signed-off-by: NJavier Martinez Canillas <javier@osg.samsung.com>
Acked-by: NAban Bedel <albeu@free.fr>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

If the driver is built as a module, autoload won't work because the module
alias information is not filled. So user-space can't match the registered
device with the corresponding module.

Export the module alias information using the MODULE_DEVICE_TABLE() macro.

Before this patch:

$ modinfo drivers/gpio/gpio-ts4800.ko | grep alias
$

After this patch:

$ modinfo drivers/gpio/gpio-ts4800.ko | grep alias
alias:          of:N*T*Ctechnologic,ts4800-gpioC*
alias:          of:N*T*Ctechnologic,ts4800-gpio
Signed-off-by: NJavier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The GPIO_GET_LINEEVENT_IOCTL currently ignores unknown or undefined
linehandle and lineevent flags. From a backwards and forwards compatibility
viewpoint it is highly desirable to reject unknown flags though.

On one hand an application that is using newer flags and is running on
an older kernel has no way to detect if the new flags were handled
correctly if they are silently discarded.

On the other hand an application that (accidentally) passes undefined flags
will run fine on an older kernel, but may break on a newer kernel when
these flags get defined.

Ensure that requests that have undefined flags set are rejected with an
error, rather than silently discarding the undefined flags.

Cc: stable@vger.kernel.org
Fixes: 61f922db ("gpio: userspace ABI for reading GPIO line events")
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The GPIO_GET_LINEHANDLE_IOCTL currently ignores unknown or undefined
linehandle flags. From a backwards and forwards compatibility viewpoint it
is highly desirable to reject unknown flags though.

On one hand an application that is using newer flags and is running on
an older kernel has no way to detect if the new flags were handled
correctly if they are silently discarded.

On the other hand an application that (accidentally) passes undefined flags
will run fine on an older kernel, but may break on a newer kernel when
these flags get defined.

Ensure that requests that have undefined flags set are rejected with an
error, rather than silently discarding the undefined flags.

Cc: stable@vger.kernel.org
Fixes: d7c51b47 ("gpio: userspace ABI for reading/writing GPIO lines")
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The GPIOHANDLE_GET_LINE_VALUES_IOCTL handler allocates a gpiohandle_data
struct on the stack and then passes it to copy_to_user(). But depending on
the number of requested line handles the struct is only partially
initialized.

This exposes the previous, potentially sensitive, stack content to the
issuing userspace application. To avoid this make sure that the struct is
fully initialized.

Cc: stable@vger.kernel.org
Fixes: d7c51b47 ("gpio: userspace ABI for reading/writing GPIO lines")
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The line offset that is used as an index into the descs array is provided
by userspace and might go beyond the bounds of the array. If that happens
undefined behavior will occur.

Make sure that the offset is within the bounds of the desc array and reject
any requests that specify a value outside of it.

Cc: stable@vger.kernel.org
Fixes: 61f922db ("gpio: userspace ABI for reading GPIO line events")
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The GPIOHANDLE_GET_LINE_VALUES_IOCTL handler allocates a gpiohandle_data
struct on the stack and then passes it to copy_to_user(). But only the
first element of the values array in the struct is set, which leaves the
struct partially initialized.

This exposes the previous, potentially sensitive, stack content to the
issuing userspace application. To avoid this make sure that the struct is
fully initialized.

Cc: stable@vger.kernel.org
Fixes: 61f922db ("gpio: userspace ABI for reading GPIO line events")
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The line offset that is used as an index into the descs array is provided
by userspace and might go beyond the bounds of the array. If that happens
undefined behavior will occur.

Make sure that the offset is within the bounds of the desc array and reject
any requests that specify a value outside of it.

Cc: stable@vger.kernel.org
Fixes: d7c51b47 ("gpio: userspace ABI for reading/writing GPIO lines")
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The GPIO_GET_CHIPINFO_IOCTL handler allocates a gpiochip_info struct on the
stack and then passes it to copy_to_user(). But depending on the length of
the GPIO chip name and label the struct is only partially initialized.

This exposes the previous, potentially sensitive, stack content to the
issuing userspace application. To avoid this make sure that the struct is
fully initialized.

Cc: stable@vger.kernel.org
Fixes: 521a2ad6 ("gpio: add userspace ABI for GPIO line information")
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The current line offset validation is off by one. Depending on the data
stored behind the descs array this can either cause undefined behavior or
disclose arbitrary, potentially sensitive, memory to the issuing userspace
application.

Make sure that offset is within the bounds of the desc array.

Cc: stable@vger.kernel.org
Fixes: 521a2ad6 ("gpio: add userspace ABI for GPIO line information")
Signed-off-by: NLars-Peter Clausen <lars@metafoo.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

acpi_dev_gpio_irq_get() currently ignores the error returned
by acpi_get_gpiod_by_index() and overwrites it with -ENOENT.

Problem is this error can be -EPROBE_DEFER, which just blows
up some drivers when the module ordering is not correct.

Cc: stable@vger.kernel.org
Signed-off-by: NDavid Arcari <darcari@redhat.com>
Signed-off-by: NBenjamin Tissoires <benjamin.tissoires@redhat.com>
Acked-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Building the gpio-mockup driver without SYSFS results in a harmless Kconfig
warning:

warning: (GPIO_MOCKUP) selects GPIO_SYSFS which has unmet direct dependencies (GPIOLIB && SYSFS)

We can easily avoid that warning by adding a dependency on SYSFS.

Fixes: 0f98dd1b ("gpio/mockup: add virtual gpio device")
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

&& was obviously intended here.

Fixes: 6936e1f8 ('gpio: stmpe: Write int status register only when needed')
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Acked-by: NPatrice Chotard <patrice.chotard@st.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Free memory mapping, if mxs_gpio_probe is not successful.
Signed-off-by: NArvind Yadav <arvind.yadav.cs@gmail.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This is a follow-up to commit 559b4699 ("gpio: pca953x: fix an
incorrect lockdep warning"). The reason for calling
lockdep_set_subclass() in pca953x_probe() is not explained in
the code.

Add a comment describing the problem, partial solution and required
future extensions.
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

of_get_named_gpiod_flags() was missing a static inline version
when compiling without OF_GPIO. Add this.
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

of_gpiochip_add() and of_gpiochip_remove() are only used locally
in the gpio subsystem so move these functions to the local
header.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The generic GPIO library directly implement code for acpi_find_gpio()
which is only used with CONFIG_ACPI. This was probably done because
OF did the same thing, but I removed that so remove this too.

Rename the internal acpi_find_gpio() in gpiolib-acpi.c to
acpi_populate_gpio_lookup() which seems to be more appropriate anyway
so as to avoid a namespace clash with the same function.

Make the stub return -ENOENT rather than -ENOSYS (as that is for
syscalls!).

For some reason the sunxi pin control driver was including the private
gpiolib header, it works just fine without it so remove that oneliner.

Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The generic GPIO library directly implement code for of_find_gpio()
which is only used with CONFIG_OF and causes compilation problems
on archs that do not even have stubs for OF functions, especially
on UM that does not implement any IO remap functions.

Move the function to gpiolib-of.c, implement a static inline stub
in gpiolib.h returning PTR_ERR(-ENOENT) if CONFIG_OF_GPIO is not
set and be done with it.
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This one is pretty obvious: on UM Linux compilation of things
like allmodconfig and allyesconfig will fail due to the
absence of IO memory. Simply make these drivers depend on
HAS_IOMEM, it has been implicitly assumed all the time, so
just make it explicit.

The generic MMIO library also assumes that IOMEM is present
so make also this depend on HAS_IOMEM.
Reported-by: Nkbuild test robot <fengguang.wu@intel.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Avoid custom (1 << bits) shifting by consequently using the
BIT() macro from <linux/bitops.h>.
Reviewed-by: NPatrice Chotard <patrice.chotard@st.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Exploit the new mechanism for masking off disallowed IRQs
added by Mika Westerberg to properly manage the STMPE
"norequest mask" to disallow also mapping said lines as
IRQs.
Reviewed-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: NPatrice Chotard <patrice.chotard@st.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

The HTC GPIO driver is a pure GPIO driver and I just can not
see what it is doing inside MFD. Let's just move it to GPIO
and take this opportunity to move the platform data to
<linux/platform_data/gpio-htc-egpio.h>

Cc: arm@kernel.org
Cc: Russell King <linux@armlinux.org.uk>
Acked-by: NLee Jones <lee.jones@linaro.org>
Acked-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

This patch add basic structure of a virtual gpio device(gpio-mockup)
for testing gpio subsystem. The tester could manipulate such device
through userspace(sysfs or char device) and check the result from
debugfs.

Currently, it support one or more gpiochip(determined by module
parameters with base,ngpio pair). One could test the overlap of
different gpiochip and test the direction and/or output values of
these chips.
Signed-off-by: NKamlakant Patel <kamlakant.patel@broadcom.com>
Signed-off-by: NBamvor Jian Zhang <bamvor.zhangjian@linaro.org>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

sparse  rightfully said:

drivers/gpio/gpio-pca953x.c:771:45: warning: symbol 'id' shadows an earlier one
drivers/gpio/gpio-pca953x.c:742:36: originally declared here

So, name them explicitly 'i2c_id' and 'acpi_id' to avoid any confusion.
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

If an I2C GPIO multiplexer is driven by a GPIO provided by an expander
when there's a second expander using the same device driver on one of
the I2C bus segments, lockdep prints a deadlock warning when trying to
set the direction or the value of the GPIOs provided by the second
expander.

The below diagram presents the setup:

                                               - - - - -
 -------             ---------  Bus segment 1 |         |
|       |           |         |---------------  Devices
|       | SCL/SDA   |         |               |         |
| Linux |-----------| I2C MUX |                - - - - -
|       |    |      |         | Bus segment 2
|       |    |      |         |-------------------
 -------     |       ---------                    |
             |           |                    - - - - -
        ------------     | MUX GPIO          |         |
       |            |    |                     Devices
       |    GPIO    |    |                   |         |
       | Expander 1 |----                     - - - - -
       |            |                             |
        ------------                              | SCL/SDA
                                                  |
                                             ------------
                                            |            |
                                            |    GPIO    |
                                            | Expander 2 |
                                            |            |
                                             ------------

The reason for lockdep warning is that we take the chip->i2c_lock in
pca953x_gpio_set_value() or pca953x_gpio_direction_output() and then
come right back to pca953x_gpio_set_value() when the GPIO mux kicks
in. The locks actually protect different expanders, but for lockdep
both are of the same class, so it says:

  Possible unsafe locking scenario:

        CPU0
        ----
   lock(&chip->i2c_lock);
   lock(&chip->i2c_lock);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

In order to get rid of the warning, retrieve the adapter nesting depth
and use it as lockdep subclass for chip->i2c_lock.
Signed-off-by: NBartosz Golaszewski <bgolaszewski@baylibre.com>
Acked-by: NPeter Rosin <peda@axentia.se>
Acked-by: NPeter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

This patch adds zynq specific check for bank 0 pins 7 and 8
are special and cannot be used as inputs
Signed-off-by: NNava kishore Manne <navam@xilinx.com>
Reported-by: NJonas Karlsson <Jonas.d.karlsson@gmail.com>
Acked-by: NSören Brinkmann <soren.brinkmann@xilinx.com>
Acked-by: NMichal Simek <michal.simek@xilinx.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Implement the get_direction callback for the GPIOs found in the AXP209
PMIC.

Due to the way they are implemented, in the same register you have the
muxing options, GPIO directions and GPIO values. Since you have no control
over what value is there at reset, simply use output as the default.
Signed-off-by: NMaxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Remove unneeded error handling on the result of a call
to platform_get_resource() when the value is passed to
devm_ioremap_resource().
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

Remove unneeded error handling on the result of a call
to platform_get_resource() when the value is passed to
devm_ioremap_resource().
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>

When using GPIO irqchip helpers to setup irqchip for a gpiolib based
driver, it is not possible to select which GPIOs to add to the IRQ domain.
Instead it just adds all GPIOs which is not always desired. For example
there might be GPIOs that for some reason cannot generated normal
interrupts at all.

To support this we add a flag irq_need_valid_mask to struct gpio_chip. When
this flag is set the core allocates irq_valid_mask that holds one bit for
each GPIO the chip has. By default all bits are set but drivers can
manipulate this using set_bit() and clear_bit() accordingly.

Then when gpiochip_irqchip_add() is called, this mask is checked and all
GPIOs with bit is set are added to the IRQ domain created for the GPIO
chip.
Suggested-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NMika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: NLinus Walleij <linus.walleij@linaro.org>