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path: root/drivers/gpio/gpiolib.c
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2017-02-23Merge tag 'gpio-v4.11-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio Pull GPIO updates from Linus Walleij: "This is the bulk of GPIO changes for the v4.11 cycle Core changes: - Augment fwnode_get_named_gpiod() to configure the GPIO pin immediately after requesting it like all other APIs do. This is a treewide change also updating all users. - Pass a GPIO label down to gpiod_request() from fwnode_get_named_gpiod(). This makes debugfs and the userspace ABI correctly reflect the current in-kernel consumer of a pin taken using this abstraction. This is a treewide change also updating all users. - Rename devm_get_gpiod_from_child() to devm_fwnode_get_gpiod_from_child() to reflect the fact that this function is operating on a fwnode object. This is a treewide change also updating all users. - Make it possible to take multiple GPIOs in a single hog of device tree hogs. - The refactorings switching GPIO chips to use the .set_config() callback using standard pin control properties and providing a backend into the pin control subsystem that were also merged into the pin control tree naturally appear here too. Testing instrumentation: - A whole slew of cleanups and improvements to the mockup GPIO driver. We now have an extended userspace test exercising the subsystem, and we can inject interrupts etc from userspace to fully test the core GPIO functionality. New drivers: - New driver for the Cortina Systems Gemini GPIO controller. - New driver for the Exar XR17V352/354/358 chips. - New driver for the ACCES PCI-IDIO-16 PCI GPIO card. Driver changes: - RCAR: set the irqchip parent device, add fine-grained runtime PM support. - pca953x: support optional RESET control line on the chip. - DaVinci: cleanups and simplifications. Add support for multiple instances. - .set_multiple() and naming of lines on more or less all of the ISA/PCI GPIO controllers. - mcp23s08: refactored to use regmap as a first step to further rewrites and modernizations" * tag 'gpio-v4.11-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (61 commits) gpio: reintroduce devm_get_gpiod_from_child() gpio: pci-idio-16: Fix PCI BAR index gpio: pci-idio-16: Fix PCI device ID code gpio: mockup: implement event injecting over debugfs gpio: mockup: add a dummy irqchip gpio: mockup: implement naming the lines gpio: mockup: code shrink gpio: mockup: readability tweaks gpio: Add GPIO support for the ACCES PCI-IDIO-16 gpio: Add the devm_fwnode_get_index_gpiod_from_child() helper gpio: Rename devm_get_gpiod_from_child() gpio: mcp23s08: Select REGMAP/REGMAP_I2C to fix build error gpio: ws16c48: Add support for GPIO names gpio: gpio-mm: Add support for GPIO names gpio: 104-idio-16: Add support for GPIO names gpio: 104-idi-48: Add support for GPIO names gpio: 104-dio-48e: Add support for GPIO names gpio: ws16c48: Remove unnecessary driver_data set gpio: gpio-mm: Remove unnecessary driver_data set gpio: 104-idio-16: Remove unnecessary driver_data set ...
2017-02-05Merge branch 'ib-gpiod-flags' into develLinus Walleij
2017-02-04gpio: Add the devm_fwnode_get_index_gpiod_from_child() helperBoris Brezillon
devm_fwnode_get_gpiod_from_child() currently allows GPIO users to request a GPIO that is defined in a child fwnode instead of directly in the device fwnode. Extend this API by adding the devm_fwnode_get_index_gpiod_from_child() helper which does the same except you can also specify an index in case the 'xx-gpios' property describe several GPIOs. Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-31gpiolib: Fix a WARN_ON that can never triggerChristophe JAILLET
"if (!x) WARN_ON(x)" can never trigger. Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-30Merge tag 'v4.10-rc6' into develLinus Walleij
Linux 4.10-rc6 Resolved conflicts in: drivers/pinctrl/pinctrl-amd.c drivers/pinctrl/samsung/pinctrl-exynos.c
2017-01-26Merge branch 'ib-pinctrl-genprops' of /home/linus/linux-pinctrl into develLinus Walleij
2017-01-26pinctrl / gpio: Introduce .set_config() callback for GPIO chipsMika Westerberg
Currently we already have two pin configuration related callbacks available for GPIO chips .set_single_ended() and .set_debounce(). In future we expect to have even more, which does not scale well if we need to add yet another callback to the GPIO chip structure for each possible configuration parameter. Better solution is to reuse what we already have available in the generic pinconf. To support this, we introduce a new .set_config() callback for GPIO chips. The callback takes a single packed pin configuration value as parameter. This can then be extended easily beyond what is currently supported by just adding new types to the generic pinconf enum. If the GPIO driver is backed up by a pinctrl driver the GPIO driver can just assign gpiochip_generic_config() (introduced in this patch) to .set_config and that will take care configuration requests are directed to the pinctrl driver. We then convert the existing drivers over .set_config() and finally remove the .set_single_ended() and .set_debounce() callbacks. Suggested-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-26Merge branch 'ib-gpiod-flags' into develLinus Walleij
2017-01-26gpio: Pass GPIO label down to gpiod_requestAlexander Stein
Currently all users of fwnode_get_named_gpiod() have no way to specify a label for the GPIO. So GPIOs listed in debugfs are shown with label "?". With this change a proper label is used. Also adjust all users so they can pass a label, properly retrieved from device tree properties. Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Jacek Anaszewski <jacek.anaszewski@gmail.com> Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-26gpiolib: Convert fwnode_get_named_gpiod() to configure GPIOAndy Shevchenko
Make fwnode_get_named_gpiod() consistent with the rest of gpiod_get() like API, i.e. configure GPIO pin immediately after request. Besides obvious clean up it will help to configure pins based on firmware provided resources. Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-19gpio: provide lockdep keys for nested/unnested irqchipsLinus Walleij
The helper function for adding a GPIO chip compiles in a lockdep key for debugging, the same key is needed for nested chips as well. The macro construction is unreadable, replace this with two static inlines instead. The _gpiochip_irqchip_add prefixed function is not helpful, rename it with gpiochip_irqchip_add_key() that tell us what the function is actually doing. Fixes: d245b3f9bd36 ("gpio: simplify adding threaded interrupts") Cc: Roger Quadros <rogerq@ti.com> Reported-by: Clemens Gruber <clemens.gruber@pqgruber.com> Reported-by: Roger Quadros <rogerq@ti.com> Reported-by: Grygorii Strashko <grygorii.strashko@ti.com> Tested-by: Clemens Gruber <clemens.gruber@pqgruber.com> Tested-by: Grygorii Strashko <grygorii.strashko@ti.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-11gpio: Remove impossible checks on container_of() resultStephen Boyd
container_of() does pointer math on the pointer that's passed in. If it were to return a NULL pointer the value passed in would need to be perfectly offset from 0 to make that so. Remove these checks because they don't make sense. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2017-01-11gpiolib: Switch to for_each_set_bit()Andy Shevchenko
The macro for_each_set_bit() effectively looks up to the next set bit in array of bits. Instead of open coding that switch to for_each_set_bit() in gpio_chip_set_multiple(). While here, make gpio_chip_set_multiple() non-destructive against its parameters. We are safe since all callers, i.e. gpiod_set_array_value_complex(), handle that already. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-12-30gpio: Move freeing of GPIO hogs before numbing of the deviceGeert Uytterhoeven
When removing a gpiochip that uses GPIO hogging (e.g. by unloading the chip's DT overlay), a warning is printed: gpio gpiochip8: REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED This happens because gpiochip_free_hogs() is called after the gdev->chip pointer is reset to NULL. Hence __gpiod_free() cannot determine the chip in use, and cannot clear flags nor call the optional chip-specific .free() callback. Move the call to gpiochip_free_hogs() up to fix this. Cc: stable@vger.kernel.org Fixes: ff2b135922992756 ("gpio: make the gpiochip a real device") Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-12-13Merge tag 'gpio-v4.10-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio Pull GPIO updates from Luinus Walleij: "Bulk GPIO changes for the v4.10 kernel cycle: Core changes: - Simplify threaded interrupt handling: instead of passing numbed parameters to gpiochip_irqchip_add_chained() we create a new call: gpiochip_irqchip_add_nested() so the two types are clearly semantically different. Also make sure that all nested chips call gpiochip_set_nested_irqchip() which is necessary for IRQ resend to work properly if it happens. - Return error on seek operations for the chardev. - Clamp values set as part of gpio[d]_direction_output() so that anything != 0 will be send down to the driver as "1" not the value passed in. - ACPI can now support naming of GPIO lines, hogs and holes in the GPIO lists. New drivers: - The SX150x driver was deemed unfit for the GPIO subsystem and was moved over to a combined GPIO+pinctrl driver in the pinctrl subsystem. New features: - Various cleanups to various drivers" * tag 'gpio-v4.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (49 commits) gpio: merrifield: Implement gpio_get_direction callback gpio: merrifield: Add support for hardware debouncer gpio: chardev: Return error for seek operations gpio: arizona: Tidy up probe error path gpio: arizona: Remove pointless set of platform drvdata gpio: pl061: delete platform data handling gpio: pl061: move platform data into driver gpio: pl061: rename variable from chip to pl061 gpio: pl061: rename state container struct gpio: pl061: use local state for parent IRQ storage gpio: set explicit nesting on drivers gpio: simplify adding threaded interrupts gpio: vf610: use builtin_platform_driver gpio: axp209: use correct register for GPIO input status gpio: stmpe: fix interrupt handling bug gpio: em: depnd on ARCH_SHMOBILE gpio: zx: depend on ARCH_ZX gpio: x86: update config dependencies for x86 specific hardware gpio: mb86s7x: use builtin_platform_driver gpio: etraxfs: use builtin_platform_driver ...
2016-12-07Merge branch 'thread-irq-simpler' into develLinus Walleij
2016-12-07gpio: chardev: Return error for seek operationsLars-Peter Clausen
The GPIO chardev is used for management tasks (allocating line and event handles) and does neither support read() nor write() operations. Hence it does not make much sense to allow seek operations. Currently the chardev uses noop_llseek() for its seek implementation. This function does not move the pointer and simply returns the current position (always 0 for the GPIO chardev). noop_llseek() is primarily meant for devices that can not support seek, but where there might be a user that depends on the seek() operation succeeding. For newly added devices that can not support seek operations it is recommended to use no_llseek(), which will return an error. For more information see commit 6038f373a3dc ("llseek: automatically add .llseek fop"). Unfortunately this was overlooked when the GPIO chardev ABI was introduced. But it is highly unlikely that since then userspace applications have appeared that rely on being able to perform non-failing seek operations on a GPIO chardev file descriptor. So it should be safe to change from noop_llseel() to no_seek(). Also use nonseekable_open() in the chardev open() callback to clear the FMODE_SEEK, FMODE_PREAD and FMODE_PWRITE flags from the file. Neither of these should be set on a file that does not support seek operations. Cc: stable@vger.kernel.org Fixes: 3c702e9987e2 ("gpio: add a userspace chardev ABI for GPIOs") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-11-25gpio: simplify adding threaded interruptsLinus Walleij
This tries to simplify the use of CONFIG_GPIOLIB_IRQCHIP when using threaded interrupts: add a new call gpiochip_irqchip_add_nested() to indicate that we're dealing with a nested rather than a chained irqchip, then create a separate gpiochip_set_nested_irqchip() to mirror the gpiochip_set_chained_irqchip() call to connect the parent and child interrupts. In the nested case gpiochip_set_nested_irqchip() does nothing more than call irq_set_parent() on each valid child interrupt, which has little semantic effect in the kernel, but this is probably still formally correct. Update all drivers using nested interrupts to use gpiochip_irqchip_add_nested() so we can now see clearly which these users are. The DLN2 driver can drop its specific hack with .irq_not_threaded as we now recognize whether a chip is threaded or not from its use of gpiochip_irqchip_add_nested() signature rather than from inspecting .can_sleep. We rename the .irq_parent to .irq_chained_parent since this parent IRQ is only really kept around for the chained interrupt handlers. Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Octavian Purdila <octavian.purdila@intel.com> Cc: Daniel Baluta <daniel.baluta@intel.com> Cc: Bin Gao <bin.gao@linux.intel.com> Cc: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: Ajay Thomas <ajay.thomas.david.rajamanickam@intel.com> Cc: Semen Protsenko <semen.protsenko@globallogic.com> Cc: Alexander Stein <alexander.stein@systec-electronic.com> Cc: Phil Reid <preid@electromag.com.au> Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com> Cc: Patrice Chotard <patrice.chotard@st.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-11-15gpio: tag line labels used for interruptsLinus Walleij
When a GPIO line is marked as used for an interrupt, it is helpful to set the label to "interrupt" so we know what is going on when inspecting the lines. If a GPIO is already properly named by gpiod_get*() we don't need to do this. It only happens when a line is used from the irqchip side of a GPIO driver without communicating with the GPIO side, such as when gpiochip is used as interrupt provider in the device tree. If the line is still marked as used by "interrupt" when we unmark it as used by an interrupt, also remove this label from the descriptor. Also shape up the code around unmarking IRQ lines. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-11-15gpio: clamp values on gpio[d]_direction_output()Linus Walleij
I saw weird values != [0,1] being passed down to drivers in their .set_direction_output() callbacks. Go over the gpiolib and make sure to hammer it to [0,1] before hitting the driver to avoid undesired side effects. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-11-15gpio: do not double-check direction on sleeping chipsLinus Walleij
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: 9c10280d85c1 ("gpio: flush direction status in gpiochip_lock_as_irq()") Cc: Patrice Chotard <patrice.chotard@st.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-10-31gpio: GPIO_GET_LINE{HANDLE,EVENT}_IOCTL: Fix file descriptor leakLars-Peter Clausen
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: d932cd49182f ("gpio: free handles in fringe cases") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-10-21gpio: GPIO_GET_LINEEVENT_IOCTL: Reject invalid line and event flagsLars-Peter Clausen
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: 61f922db7221 ("gpio: userspace ABI for reading GPIO line events") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-10-21gpio: GPIO_GET_LINEHANDLE_IOCTL: Reject invalid line flagsLars-Peter Clausen
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: d7c51b47ac11 ("gpio: userspace ABI for reading/writing GPIO lines") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-10-21gpio: GPIOHANDLE_GET_LINE_VALUES_IOCTL: Fix information leakLars-Peter Clausen
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: d7c51b47ac11 ("gpio: userspace ABI for reading/writing GPIO lines") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-10-21gpio: GPIO_GET_LINEEVENT_IOCTL: Validate line offsetLars-Peter Clausen
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: 61f922db7221 ("gpio: userspace ABI for reading GPIO line events") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-10-21gpio: GPIOHANDLE_GET_LINE_VALUES_IOCTL: Fix information leakLars-Peter Clausen
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: 61f922db7221 ("gpio: userspace ABI for reading GPIO line events") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-10-21gpio: GPIO_GET_LINEHANDLE_IOCTL: Validate line offsetLars-Peter Clausen
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: d7c51b47ac11 ("gpio: userspace ABI for reading/writing GPIO lines") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-10-21gpio: GPIO_GET_CHIPINFO_IOCTL: Fix information leakLars-Peter Clausen
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: 521a2ad6f862 ("gpio: add userspace ABI for GPIO line information") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-10-21gpio: GPIO_GET_CHIPINFO_IOCTL: Fix line offset validationLars-Peter Clausen
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: 521a2ad6f862 ("gpio: add userspace ABI for GPIO line information") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-10-03gpio: acpi: separation of concernsLinus Walleij
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: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-10-03gpio: OF: separation of concernsLinus Walleij
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: Linus Walleij <linus.walleij@linaro.org>
2016-09-23Merge branch 'gpio-irq-validmask' of /home/linus/linux-pinctrl into develLinus Walleij
2016-09-23gpiolib: Make it possible to exclude GPIOs from IRQ domainMika Westerberg
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: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-09-13gpiolib: Forbid irqchip default trigger for ACPI enumerated devicesMika Westerberg
Follow DT and forbid default trigger if the GPIO irqchip device is enumerated from ACPI. Triggering for these devices will be configured automatically from ACPI interrupt resources provided by the BIOS. Suggested-by: Linus Walleij <linus.walleij@linaro.org> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-09-12gpio/gpiolib: Forbid irqchip default trigger if probed over DTMarc Zyngier
Using a default trigger is a bad idea if using DT to configure interrupts, as the device's interrupt specifier will always contain the trigger configuration. Let's warn about that particular situation, and revert to not having a default. Hopefully, the couple of drivers still using this feature will quickly be fixed. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-08-19gpio: refactor gpiochip_find() slightlyMasahiro Yamada
The if...else... block after the loop can be dropped with a slight refactoring. Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-07-26Merge tag 'gpio-v4.8-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio Pull GPIO updates from Linus Walleij: "This is the bulk of GPIO changes for the v4.8 kernel cycle. The big news is the completion of the chardev ABI which I'm very happy about and apart from that it's an ordinary, quite busy cycle. The details are below. The patches are tested in linux-next for some time, patches to other subsystem mostly have ACKs. I got overly ambitious with configureing lines as input for IRQ lines but it turns out that some controllers have their interrupt-enable and input-enabling in orthogonal settings so the assumption that all IRQ lines are input lines does not hold. Oh well, revert and back to the drawing board with that. Core changes: - The big item is of course the completion of the character device ABI. It has now replaced and surpassed the former unmaintainable sysfs ABI: we can now hammer (bitbang) individual lines or sets of lines and read individual lines or sets of lines from userspace, and we can also register to listen to GPIO events from userspace. As a tie-in we have two new tools in tools/gpio: gpio-hammer and gpio-event-mon that illustrate the proper use of the new ABI. As someone said: the wild west days of GPIO are now over. - Continued to remove the pointless ARCH_[WANT_OPTIONAL|REQUIRE]_GPIOLIB Kconfig symbols. I'm patching hexagon, openrisc, powerpc, sh, unicore, ia64 and microblaze. These are either ACKed by their maintainers or patched anyways after a grace period and no response from maintainers. Some archs (ARM) come in from their trees, and others (x86) are still not fixed, so I might send a second pull request to root it out later in this merge window, or just defer to v4.9. - The GPIO tools are moved to the tools build system. New drivers: - New driver for the MAX77620/MAX20024. - New driver for the Intel Merrifield. - Enabled PCA953x for the TI PCA9536. - Enabled PCA953x for the Intel Edison. - Enabled R8A7792 in the RCAR driver. Driver improvements: - The STMPE and F7188x now supports the .get_direction() callback. - The Xilinx driver supports setting multiple lines at once. - ACPI support for the Vulcan GPIO controller. - The MMIO GPIO driver supports device tree probing. - The Acer One 10 is supported through the _DEP ACPI attribute. Cleanups: - A major cleanup of the OF/DT support code. It is way easier to read and understand now, probably this improves performance too. - Drop a few redundant .owner assignments. - Remove CLPS711x boardfile support: we are 100% DT" * tag 'gpio-v4.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (67 commits) MAINTAINERS: Add INTEL MERRIFIELD GPIO entry gpio: dwapb: add missing fwnode_handle_put() in dwapb_gpio_get_pdata() gpio: merrifield: Protect irq_ack() and gpio_set() by lock gpio: merrifield: Introduce GPIO driver to support Merrifield gpio: intel-mid: Make it depend to X86_INTEL_MID gpio: intel-mid: Sort header block alphabetically gpio: intel-mid: Remove potentially harmful code gpio: rcar: add R8A7792 support gpiolib: remove duplicated include from gpiolib.c Revert "gpio: convince line to become input in irq helper" gpiolib: of_find_gpio(): Don't discard errors gpio: of: Allow overriding the device node gpio: free handles in fringe cases gpio: tps65218: Add platform_device_id table gpio: max77620: get gpio value based on direction gpio: lynxpoint: avoid potential warning on error path tools/gpio: add install section tools/gpio: move to tools buildsystem gpio: intel-mid: switch to devm_gpiochip_add_data() gpio: 74x164: Use spi_write() helper instead of open coding ...
2016-07-22gpiolib: remove duplicated include from gpiolib.cWei Yongjun
Remove duplicated include. Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-07-06Revert "gpio: convince line to become input in irq helper"Linus Walleij
This reverts commit 7e7c059cb50c7c72d5a393b2c34fc57de1b01b55. I was wrong about trying to do this, as it breaks the orthogonality between gpiochips and irqchips. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-07-06gpiolib: of_find_gpio(): Don't discard errorsLars-Peter Clausen
Since commit dd34c37aa3e8 ("gpio: of: Allow -gpio suffix for property names") when requesting a GPIO from the devicetree gpiolib looks for properties with both the '-gpio' and the '-gpios' suffix. This was implemented by first searching for the property with the '-gpios' suffix and if that yields an error try the '-gpio' suffix. This approach has the issue that any error returned when looking for the '-gpios' suffix is silently discarded. Commit 06fc3b70f1dc ("gpio: of: Fix handling for deferred probe for -gpio suffix") partially addressed the issue by treating the EPROBE_DEFER error as a special condition. This fixed the case when the property is specified, but the GPIO provider is not ready yet. But there are other cases in which of_get_named_gpiod_flags() returns an error even though the property is specified, e.g. if the specification is incorrect. of_find_gpio() should only try to look for the property with the '-gpio' suffix if no property with the '-gpios' suffix was found. If the property was not found of_get_named_gpiod_flags() will return -ENOENT, so update the condition to abort and propagate the error to the caller in all other cases. This is important for gpiod_get_optinal() and friends to behave correctly in case the specifier contains errors. Without this patch they'll return NULL if the property uses the '-gpios' suffix and the specifier contains errors, which falsely indicates to the caller that no GPIO was specified. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-07-06gpio: of: Allow overriding the device nodeThierry Reding
When registering a GPIO chip, drivers can override the device tree node associated with the chip by setting the chip's ->of_node field. If set, this field is supposed to take precedence over the ->parent->of_node field, but the code doesn't actually do that. Commit 762c2e46c059 ("gpio: of: remove of_gpiochip_and_xlate() and struct gg_data") exposes this because it now no longer matches on the GPIO chip's ->of_node field, but the GPIO device's ->of_node field that is set using the procedure described above. Signed-off-by: Thierry Reding <treding@nvidia.com> Acked-by: Alexandre Courbot <acourbot@nvidia.com> Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-07-04gpio: free handles in fringe casesLinus Walleij
If we fail when copying the ioctl() struct to userspace we still need to clean up the cruft otherwise left behind or it will stay around until the issuing process terminates the file handle. Reported-by: Alexander Stein <alexander.stein@systec-electronic.com> Acked-by: Alexander Stein <alexander.stein@systec-electronic.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-07-04Revert "gpiolib: Split GPIO flags parsing and GPIO configuration"Johan Hovold
This reverts commit 923b93e451db876d1479d3e4458fce14fec31d1c. Make sure consumers do not overwrite gpio flags for pins that have already been claimed. While adding support for gpio drivers to refuse a request using unsupported flags, the order of when the requested flag was checked and the new flags were applied was reversed to that consumers could overwrite flags for already requested gpios. This not only affects device-tree setups where two drivers could request the same gpio using conflicting configurations, but also allowed user space to clear gpio flags for already claimed pins simply by attempting to export them through the sysfs interface. By for example clearing the FLAG_ACTIVE_LOW flag this way, user space could effectively change the polarity of a signal. Reverting this change obviously prevents gpio drivers from doing sanity checks on the flags in their request callbacks. Fortunately only one recently added driver (gpio-tps65218 in v4.6) appears to do this, and a follow up patch could restore this functionality through a different interface. Cc: stable <stable@vger.kernel.org> # 4.4 Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-23gpio: convince line to become input in irq helperLinus Walleij
The generic IRQ helper library just checks if the IRQ line is set as input before activating it for interrupts. As we recently started to check things better with .get_dir() it turns out that it's good to try to convince the line to become an input before attempting to lock it as IRQ. Reviewed-by: Björn Andersson <bjorn.andersson@linaro.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-18gpiolib: make lineevent_irq_thread staticBen Dooks
The lineevent_irq_thread is not exported, so make it static to fix the following warning: drivers/gpio/gpiolib.c:654:13: warning: symbol 'lineevent_irq_thread' was not declared. Should it be static? Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-18gpio: make the iterator point to last handleLinus Walleij
When initializing the GPIO handles, we use the iterator (i) to back off if something goes wrong. But since the iterator is also used after we pass the loop, we must decrement by one after exiting the loop so that we point at the last element in the array. Reported-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: Walter Harms <wharms@bfs.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-17gpio: make library immune to error pointersLinus Walleij
Most functions that take a GPIO descriptor in need to check the descriptor for IS_ERR(). We do this mostly in the VALIDATE_DESC() macro except for the gpiod_to_irq() function which needs special handling. Cc: stable@vger.kernel.org Reported-by: Grygorii Strashko <grygorii.strashko@ti.com> Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com> Acked-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-17gpio: make sure gpiod_to_irq() returns negative on NULL descLinus Walleij
commit 54d77198fdfbc4f0fe11b4252c1d9c97d51a3264 ("gpio: bail out silently on NULL descriptors") doesn't work for gpiod_to_irq(): drivers assume that NULL descriptors will give negative IRQ numbers in return. It has been pointed out that returning 0 is NO_IRQ and that drivers should be amended to treat this as an error, but that is for the longer term: now let us repair the semantics. Cc: Maxime Ripard <maxime.ripard@free-electrons.com> Reported-by: Hans de Goede <hdegoede@redhat.com> Tested-by: Hans de Goede <hdegoede@redhat.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-16gpiolib: avoid uninitialized data in gpio kfifoArnd Bergmann
gcc reports a theoretical case for returning uninitialized data in the kfifo when a GPIO interrupt happens and neither GPIOEVENT_REQUEST_RISING_EDGE nor GPIOEVENT_REQUEST_FALLING_EDGE are set: drivers/gpio/gpiolib.c: In function 'lineevent_irq_thread': drivers/gpio/gpiolib.c:683:87: error: 'ge.id' may be used uninitialized in this function [-Werror=maybe-uninitialized] This case should not happen, but to be on the safe side, let's return from the irq handler without adding data to the FIFO to ensure we can never leak stack data to user space. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Fixes: 61f922db7221 ("gpio: userspace ABI for reading GPIO line events") Signed-off-by: Linus Walleij <linus.walleij@linaro.org>