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Documentation: gpio: Move GPIO mapping documentation to driver-api Move gpio/board.txt to driver-api/gpio/board.rst and make sure it builds cleanly as ReST. Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-03-09 00:40:23 +01:00
Documentation: gpiolib: document new interface gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-16 21:34:21 +09:00
gpio: Documentation update Update a slew of documentation files with the latest changes in the API/ABI. Again stress that sysfs is deprecated. Add all new flags and clean up and move some text. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-01-18 10:43:43 +01:00
gpio: delete ARCH_[WANTS_OPTIONAL|REQUIRE]_GPIOLIB The GPIOLIB is now selectable explicitly, and always available for all archs. All archs that require GPIOLIB are switched to select GPIOLIB directly. Delete the hairy ARCH_REQUIRE_GPIOLIB and ARCH_WANTS_OPTIONAL_GPIOLIB Kconfig symbols. Cc: Michael Büsch <m@bues.ch> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-04-19 13:40:17 +02:00
Documentation: gpiolib: document new interface gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-16 21:34:21 +09:00
Documentation: gpio: mention that <function>-gpio has been deprecated The gpiolib supports parsing DT properties of the form <function>-gpio but it was only added for compatibility with older DT bindings that got it wrong and should not be used in newer bindings. The commit that added support for this was: dd34c37aa3e8 ("gpio: of: Allow -gpio suffix for property names") but didn't update the documentation to explain this so it's been a source of confusion. So let's make clear this in the GPIO documentation. Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-09-21 15:14:46 +02:00
Documentation: gpio: Move GPIO mapping documentation to driver-api Move gpio/board.txt to driver-api/gpio/board.rst and make sure it builds cleanly as ReST. Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-03-09 00:40:23 +01:00
Documentation: gpiolib: document new interface gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-16 21:34:21 +09:00
Documentation: gpio: mention that <function>-gpio has been deprecated The gpiolib supports parsing DT properties of the form <function>-gpio but it was only added for compatibility with older DT bindings that got it wrong and should not be used in newer bindings. The commit that added support for this was: dd34c37aa3e8 ("gpio: of: Allow -gpio suffix for property names") but didn't update the documentation to explain this so it's been a source of confusion. So let's make clear this in the GPIO documentation. Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-09-21 15:14:46 +02:00
Documentation: gpiolib: document new interface gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-16 21:34:21 +09:00
Documentation: gpio: mention that <function>-gpio has been deprecated The gpiolib supports parsing DT properties of the form <function>-gpio but it was only added for compatibility with older DT bindings that got it wrong and should not be used in newer bindings. The commit that added support for this was: dd34c37aa3e8 ("gpio: of: Allow -gpio suffix for property names") but didn't update the documentation to explain this so it's been a source of confusion. So let's make clear this in the GPIO documentation. Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-09-21 15:14:46 +02:00
Documentation: gpiolib: document new interface gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-16 21:34:21 +09:00
Documentation: gpio: Move GPIO mapping documentation to driver-api Move gpio/board.txt to driver-api/gpio/board.rst and make sure it builds cleanly as ReST. Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-03-09 00:40:23 +01:00
Documentation: gpiolib: document new interface gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-16 21:34:21 +09:00
Documentation: gpio: board: add flags parameter to gpiod_get*() functions With commit 39b2bbe3d715 ("gpio: add flags argument to gpiod_get*() functions") the gpiod_get*() functions got a 'flags' parameter. Reflect this in the documentation, too. Signed-off-by: Dirk Behme <dirk.behme@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-09-02 20:07:09 +02:00
Documentation: gpiolib: document new interface gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-16 21:34:21 +09:00
Documentation: gpio: board: add flags parameter to gpiod_get*() functions With commit 39b2bbe3d715 ("gpio: add flags argument to gpiod_get*() functions") the gpiod_get*() functions got a 'flags' parameter. Reflect this in the documentation, too. Signed-off-by: Dirk Behme <dirk.behme@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-09-02 20:07:09 +02:00
Documentation: gpiolib: document new interface gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-16 21:34:21 +09:00
gpio: Documentation update Update a slew of documentation files with the latest changes in the API/ABI. Again stress that sysfs is deprecated. Add all new flags and clean up and move some text. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-01-18 10:43:43 +01:00
Documentation: gpiolib: document new interface gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-16 21:34:21 +09:00
Documentation: gpio: board: describe the con_id parameter The con_id parameter has to match the GPIO description and is automatically extended by the GPIO suffix if not NULL. I had to look into the code to understand this and properly find the GPIO I've been looking for, so document this. Signed-off-by: Dirk Behme <dirk.behme@gmail.com> Acked-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-09-02 20:07:10 +02:00
Documentation: gpio: Move GPIO mapping documentation to driver-api Move gpio/board.txt to driver-api/gpio/board.rst and make sure it builds cleanly as ReST. Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-03-09 00:40:23 +01:00
Documentation: gpio: board: describe the con_id parameter The con_id parameter has to match the GPIO description and is automatically extended by the GPIO suffix if not NULL. I had to look into the code to understand this and properly find the GPIO I've been looking for, so document this. Signed-off-by: Dirk Behme <dirk.behme@gmail.com> Acked-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-09-02 20:07:10 +02:00
Documentation: gpiolib: document new interface gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-16 21:34:21 +09:00
Documentation: gpio: Update ACPI part of the document to mention _DSD With ACPI 5.1 _DSD (Device Specific Data) it is now possible to name functions just like Device Tree is doing. Make sure that the documentation mentions _DSD as the recommended way to describe GPIOs in ACPI systems. Reported-by: Darren Hart <dvhart@linux.intel.com> Reviewed-by: Darren Hart <dvhart@linux.intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-04-01 11:13:16 +03:00
Documentation: gpio: Move GPIO mapping documentation to driver-api Move gpio/board.txt to driver-api/gpio/board.rst and make sure it builds cleanly as ReST. Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-03-09 00:40:23 +01:00
Documentation: gpio: Update ACPI part of the document to mention _DSD With ACPI 5.1 _DSD (Device Specific Data) it is now possible to name functions just like Device Tree is doing. Make sure that the documentation mentions _DSD as the recommended way to describe GPIOs in ACPI systems. Reported-by: Darren Hart <dvhart@linux.intel.com> Reviewed-by: Darren Hart <dvhart@linux.intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-04-01 11:13:16 +03:00
ACPI: docs: gpio-properties: Unify ASL style for GPIO examples GPIO examples of ASL in the board.rst, enumeration.rst and gpio-properties.rst are not unified. Unify them for better reader experience. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-03-08 16:05:59 +02:00
Documentation: gpio: Update ACPI part of the document to mention _DSD With ACPI 5.1 _DSD (Device Specific Data) it is now possible to name functions just like Device Tree is doing. Make sure that the documentation mentions _DSD as the recommended way to describe GPIOs in ACPI systems. Reported-by: Darren Hart <dvhart@linux.intel.com> Reviewed-by: Darren Hart <dvhart@linux.intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-04-01 11:13:16 +03:00
ACPI: docs: gpio-properties: Unify ASL style for GPIO examples GPIO examples of ASL in the board.rst, enumeration.rst and gpio-properties.rst are not unified. Unify them for better reader experience. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2022-03-08 16:05:59 +02:00
Documentation: gpio: Update ACPI part of the document to mention _DSD With ACPI 5.1 _DSD (Device Specific Data) it is now possible to name functions just like Device Tree is doing. Make sure that the documentation mentions _DSD as the recommended way to describe GPIOs in ACPI systems. Reported-by: Darren Hart <dvhart@linux.intel.com> Reviewed-by: Darren Hart <dvhart@linux.intel.com> Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-04-01 11:13:16 +03:00
docs: fix broken documentation links Mostly due to x86 and acpi conversion, several documentation links are still pointing to the old file. Fix them. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Reviewed-by: Wolfram Sang <wsa@the-dreams.de> Reviewed-by: Sven Van Asbroeck <TheSven73@gmail.com> Reviewed-by: Bhupesh Sharma <bhsharma@redhat.com> Acked-by: Mark Brown <broonie@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2019-06-07 15:54:32 -03:00
Documentation: gpiolib: document new interface gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-16 21:34:21 +09:00
Documentation: gpio: add documentation about using software nodes Introduce documentation regarding use of software nodes to describe GPIOs on legacy boards that have not been converted to device tree. Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Tested-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/tnaaz2qlk5jpbonfle7uy7pb54qx6ixwuczfbkwtxxwpj7hwas@y7a2rwko3k6c Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-08-17 14:30:20 -07:00
Documentation: gpio: update the preferred method for using software node lookup In its current version, the manual for converting of board files from using GPIO lookup tables to software nodes recommends leaving the software nodes representing GPIO controllers as "free-floating", not attached objects and relying on the matching of their names against the GPIO controller's name. This is an abuse of the software node API and makes it impossible to create fw_devlinks between GPIO suppliers and consumers in this case. We want to remove this behavior from GPIOLIB and to this end, work on converting all existing drivers to using "attached" software nodes. Except for a few corner-cases where board files define consumers depending on GPIO controllers described in firmware - where we need to reference a real firmware node from a software node - which requires a more complex approach, most board files can easily be converted to using propert firmware node lookup. Update the documentation to recommend attaching the GPIO chip's software nodes to the actual platform devices and show how to do it. Reviewed-by: Linus Walleij <linusw@kernel.org> Link: https://patch.msgid.link/20260403-doc-gpio-swnodes-v2-1-c705f5897b80@oss.qualcomm.com Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
2026-04-03 15:04:55 +02:00
Documentation: gpio: add documentation about using software nodes Introduce documentation regarding use of software nodes to describe GPIOs on legacy boards that have not been converted to device tree. Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Tested-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/tnaaz2qlk5jpbonfle7uy7pb54qx6ixwuczfbkwtxxwpj7hwas@y7a2rwko3k6c Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-08-17 14:30:20 -07:00
Documentation: gpio: update the preferred method for using software node lookup In its current version, the manual for converting of board files from using GPIO lookup tables to software nodes recommends leaving the software nodes representing GPIO controllers as "free-floating", not attached objects and relying on the matching of their names against the GPIO controller's name. This is an abuse of the software node API and makes it impossible to create fw_devlinks between GPIO suppliers and consumers in this case. We want to remove this behavior from GPIOLIB and to this end, work on converting all existing drivers to using "attached" software nodes. Except for a few corner-cases where board files define consumers depending on GPIO controllers described in firmware - where we need to reference a real firmware node from a software node - which requires a more complex approach, most board files can easily be converted to using propert firmware node lookup. Update the documentation to recommend attaching the GPIO chip's software nodes to the actual platform devices and show how to do it. Reviewed-by: Linus Walleij <linusw@kernel.org> Link: https://patch.msgid.link/20260403-doc-gpio-swnodes-v2-1-c705f5897b80@oss.qualcomm.com Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
2026-04-03 15:04:55 +02:00
Documentation: gpio: add documentation about using software nodes Introduce documentation regarding use of software nodes to describe GPIOs on legacy boards that have not been converted to device tree. Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Tested-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/tnaaz2qlk5jpbonfle7uy7pb54qx6ixwuczfbkwtxxwpj7hwas@y7a2rwko3k6c Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-08-17 14:30:20 -07:00
Documentation: gpio: update the preferred method for using software node lookup In its current version, the manual for converting of board files from using GPIO lookup tables to software nodes recommends leaving the software nodes representing GPIO controllers as "free-floating", not attached objects and relying on the matching of their names against the GPIO controller's name. This is an abuse of the software node API and makes it impossible to create fw_devlinks between GPIO suppliers and consumers in this case. We want to remove this behavior from GPIOLIB and to this end, work on converting all existing drivers to using "attached" software nodes. Except for a few corner-cases where board files define consumers depending on GPIO controllers described in firmware - where we need to reference a real firmware node from a software node - which requires a more complex approach, most board files can easily be converted to using propert firmware node lookup. Update the documentation to recommend attaching the GPIO chip's software nodes to the actual platform devices and show how to do it. Reviewed-by: Linus Walleij <linusw@kernel.org> Link: https://patch.msgid.link/20260403-doc-gpio-swnodes-v2-1-c705f5897b80@oss.qualcomm.com Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
2026-04-03 15:04:55 +02:00
Documentation: gpio: add documentation about using software nodes Introduce documentation regarding use of software nodes to describe GPIOs on legacy boards that have not been converted to device tree. Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Tested-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Link: https://lore.kernel.org/r/tnaaz2qlk5jpbonfle7uy7pb54qx6ixwuczfbkwtxxwpj7hwas@y7a2rwko3k6c Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
2025-08-17 14:30:20 -07:00
Documentation: gpiolib: document new interface gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-16 21:34:21 +09:00
Documentation: gpio: Move GPIO mapping documentation to driver-api Move gpio/board.txt to driver-api/gpio/board.rst and make sure it builds cleanly as ReST. Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-03-09 00:40:23 +01:00
Documentation: gpiolib: document new interface gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-16 21:34:21 +09:00
gpio: split gpiod board registration into machine header As per example from the regulator subsystem: put all defines and functions related to registering board info for GPIO descriptors into a separate <linux/gpio/machine.h> header. Cc: Andrew Victor <linux@maxim.org.za> Cc: Nicolas Ferre <nicolas.ferre@atmel.com> Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Thierry Reding <thierry.reding@gmail.com> Acked-by: Stephen Warren <swarren@wwwdotorg.org> Reviewed-by: Alexandre Courbot <gnurou@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-07-24 20:08:55 +02:00
Documentation: gpiolib: document new interface gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-16 21:34:21 +09:00
Documentation: gpio: Move GPIO mapping documentation to driver-api Move gpio/board.txt to driver-api/gpio/board.rst and make sure it builds cleanly as ReST. Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-03-09 00:40:23 +01:00
Documentation: gpiolib: document new interface gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-16 21:34:21 +09:00
gpiolib: Add support for GPIO lookup by line name Currently a GPIO lookup table can only refer to a specific GPIO by a tuple, consisting of a GPIO controller label and a GPIO offset inside the controller. However, a GPIO may also carry a line name, defined by DT or ACPI. If present, the line name is the most use-centric way to refer to a GPIO. Hence add support for looking up GPIOs by line name. Note that there is no guarantee that GPIO line names are globally unique, so this will use the first match found. Implement this by reusing the existing gpiod_lookup infrastructure. Rename gpiod_lookup.chip_label to gpiod_lookup.key, to make it clear that this field can have two meanings, and update the kerneldoc and GPIO_LOOKUP*() macros. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Tested-by: Eugeniu Rosca <erosca@de.adit-jv.com> Reviewed-by: Ulrich Hecht <uli+renesas@fpond.eu> Reviewed-by: Eugeniu Rosca <erosca@de.adit-jv.com> Link: https://lore.kernel.org/r/20200511145257.22970-4-geert+renesas@glider.be Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2020-05-11 16:52:54 +02:00
Documentation: gpiolib: document new interface gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-16 21:34:21 +09:00
gpiolib: Add support for GPIO lookup by line name Currently a GPIO lookup table can only refer to a specific GPIO by a tuple, consisting of a GPIO controller label and a GPIO offset inside the controller. However, a GPIO may also carry a line name, defined by DT or ACPI. If present, the line name is the most use-centric way to refer to a GPIO. Hence add support for looking up GPIOs by line name. Note that there is no guarantee that GPIO line names are globally unique, so this will use the first match found. Implement this by reusing the existing gpiod_lookup infrastructure. Rename gpiod_lookup.chip_label to gpiod_lookup.key, to make it clear that this field can have two meanings, and update the kerneldoc and GPIO_LOOKUP*() macros. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Tested-by: Eugeniu Rosca <erosca@de.adit-jv.com> Reviewed-by: Ulrich Hecht <uli+renesas@fpond.eu> Reviewed-by: Eugeniu Rosca <erosca@de.adit-jv.com> Link: https://lore.kernel.org/r/20200511145257.22970-4-geert+renesas@glider.be Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2020-05-11 16:52:54 +02:00
Documentation: gpiolib: document new interface gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-16 21:34:21 +09:00
gpio: better lookup method for platform GPIOs Change the format of the platform GPIO lookup tables to make them less confusing and improve lookup efficiency. The previous format was a single linked-list that required to compare the device name and function ID of every single GPIO defined for each lookup. Switch that to a list of per-device tables, so that the lookup can be done in two steps, omitting the GPIOs that are not relevant for a particular device. The matching rules are now defined as follows: - The device name must match *exactly*, and can be NULL for GPIOs not assigned to a particular device, - If the function ID in the lookup table is NULL, the con_id argument of gpiod_get() will not be used for lookup. However, if it is defined, it must match exactly. - The index must always match. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Acked-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>
2013-12-03 12:20:11 +09:00
Documentation: gpiolib: document new interface gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-16 21:34:21 +09:00
gpio: Documentation update Update a slew of documentation files with the latest changes in the API/ABI. Again stress that sysfs is deprecated. Add all new flags and clean up and move some text. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-01-18 10:43:43 +01:00
gpio: Fix a documentation spelling mistake Simple etraneous letter. Reported-by: Alexander Stein <alexander.stein@systec-electronic.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-01-21 16:52:31 +01:00
gpio: Documentation update Update a slew of documentation files with the latest changes in the API/ABI. Again stress that sysfs is deprecated. Add all new flags and clean up and move some text. Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-01-18 10:43:43 +01:00
Documentation: gpiolib: document new interface gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-16 21:34:21 +09:00
gpiolib: Add support for GPIO lookup by line name Currently a GPIO lookup table can only refer to a specific GPIO by a tuple, consisting of a GPIO controller label and a GPIO offset inside the controller. However, a GPIO may also carry a line name, defined by DT or ACPI. If present, the line name is the most use-centric way to refer to a GPIO. Hence add support for looking up GPIOs by line name. Note that there is no guarantee that GPIO line names are globally unique, so this will use the first match found. Implement this by reusing the existing gpiod_lookup infrastructure. Rename gpiod_lookup.chip_label to gpiod_lookup.key, to make it clear that this field can have two meanings, and update the kerneldoc and GPIO_LOOKUP*() macros. Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> Tested-by: Eugeniu Rosca <erosca@de.adit-jv.com> Reviewed-by: Ulrich Hecht <uli+renesas@fpond.eu> Reviewed-by: Eugeniu Rosca <erosca@de.adit-jv.com> Link: https://lore.kernel.org/r/20200511145257.22970-4-geert+renesas@glider.be Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2020-05-11 16:52:54 +02:00
Documentation: gpiolib: document new interface gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-16 21:34:21 +09:00
gpio: better lookup method for platform GPIOs Change the format of the platform GPIO lookup tables to make them less confusing and improve lookup efficiency. The previous format was a single linked-list that required to compare the device name and function ID of every single GPIO defined for each lookup. Switch that to a list of per-device tables, so that the lookup can be done in two steps, omitting the GPIOs that are not relevant for a particular device. The matching rules are now defined as follows: - The device name must match *exactly*, and can be NULL for GPIOs not assigned to a particular device, - If the function ID in the lookup table is NULL, the con_id argument of gpiod_get() will not be used for lookup. However, if it is defined, it must match exactly. - The index must always match. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Acked-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>
2013-12-03 12:20:11 +09:00
gpio: documenatation: fix GPIO_LOOKUP{,_IDX} documentation The 'dev_id' parameter of the GPIO_LOOKUP{,_IDX} macros were removed by commit ad824783fb23 ("gpio: better lookup method for platform GPIOs"). Update the documentation to reflect that. Signed-off-by: Gabor Juhos <juhosg@openwrt.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-02-25 08:00:45 +01:00
Documentation: gpiolib: document new interface gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-16 21:34:21 +09:00
Documentation: gpio: Move GPIO mapping documentation to driver-api Move gpio/board.txt to driver-api/gpio/board.rst and make sure it builds cleanly as ReST. Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-03-09 00:40:23 +01:00
Documentation: gpiolib: document new interface gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-16 21:34:21 +09:00
Documentation: gpio: Move GPIO mapping documentation to driver-api Move gpio/board.txt to driver-api/gpio/board.rst and make sure it builds cleanly as ReST. Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-03-09 00:40:23 +01:00
Documentation: gpiolib: document new interface gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-16 21:34:21 +09:00
gpio: better lookup method for platform GPIOs Change the format of the platform GPIO lookup tables to make them less confusing and improve lookup efficiency. The previous format was a single linked-list that required to compare the device name and function ID of every single GPIO defined for each lookup. Switch that to a list of per-device tables, so that the lookup can be done in two steps, omitting the GPIOs that are not relevant for a particular device. The matching rules are now defined as follows: - The device name must match *exactly*, and can be NULL for GPIOs not assigned to a particular device, - If the function ID in the lookup table is NULL, the con_id argument of gpiod_get() will not be used for lookup. However, if it is defined, it must match exactly. - The index must always match. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Acked-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>
2013-12-03 12:20:11 +09:00
Documentation: gpiolib: document new interface gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-16 21:34:21 +09:00
Documentation: gpio: Move GPIO mapping documentation to driver-api Move gpio/board.txt to driver-api/gpio/board.rst and make sure it builds cleanly as ReST. Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-03-09 00:40:23 +01:00
Documentation: gpiolib: document new interface gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-16 21:34:21 +09:00
Documentation: gpio: board: add flags parameter to gpiod_get*() functions With commit 39b2bbe3d715 ("gpio: add flags argument to gpiod_get*() functions") the gpiod_get*() functions got a 'flags' parameter. Reflect this in the documentation, too. Signed-off-by: Dirk Behme <dirk.behme@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-09-02 20:07:09 +02:00
Documentation: gpiolib: document new interface gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-16 21:34:21 +09:00
Documentation: gpio: board: add flags parameter to gpiod_get*() functions With commit 39b2bbe3d715 ("gpio: add flags argument to gpiod_get*() functions") the gpiod_get*() functions got a 'flags' parameter. Reflect this in the documentation, too. Signed-off-by: Dirk Behme <dirk.behme@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-09-02 20:07:09 +02:00
Documentation: gpiolib: document new interface gpiolib now exports a new descriptor-based interface which deprecates the older integer-based one. This patch documents this new interface and also takes the opportunity to brush-up the GPIO documentation a little bit. The new descriptor-based interface follows the same consumer/driver model as many other kernel subsystems (e.g. clock, regulator), so its documentation has similarly been splitted into different files. The content of the former documentation has been reused whenever it made sense; however, some of its content did not apply to the new interface anymore and have this been removed. Likewise, new sections like the mapping of GPIOs to devices have been written from scratch. The deprecated legacy-based documentation is still available, untouched, under Documentation/gpio/gpio-legacy.txt. Signed-off-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-11-16 21:34:21 +09:00
Documentation: gpio: board: add flags parameter to gpiod_get*() functions With commit 39b2bbe3d715 ("gpio: add flags argument to gpiod_get*() functions") the gpiod_get*() functions got a 'flags' parameter. Reflect this in the documentation, too. Signed-off-by: Dirk Behme <dirk.behme@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-09-02 20:07:09 +02:00
gpio/board.txt: point to gpiod_set_value gpiod_set_value() is preffered interface these days, so add a pointer. Also fix a missing ). Signed-off-by: Pavel Machek <pavel@ucw.cz> [Fixed some grammar and reworded] Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-10-03 10:43:46 +02:00
gpiolib: add hogs support for machine code Board files constitute a significant part of the users of the legacy GPIO framework. In many cases they only export a line and set its desired value. We could use GPIO hogs for that like we do for DT and ACPI but there's no support for that in machine code. This patch proposes to extend the machine.h API with support for registering hog tables in board files. Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-04-10 22:30:28 +02:00
gpiolib: Implement fast processing path in get/set array Certain GPIO descriptor arrays returned by gpio_get_array() may contain information on direct mapping of array members to pins of a single GPIO chip in hardware order. In such cases, bitmaps of values can be passed directly from/to the chip's .get/set_multiple() callbacks without wasting time on iterations. Add respective code to gpiod_get/set_array_bitmap_complex() functions. Pins not applicable for fast path are processed as before, skipping over the 'fast' ones. Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-05 23:50:08 +02:00
gpiolib: Fix array members of same chip processed separately New code introduced by commit bf9346f5d47b ("gpiolib: Identify arrays matching GPIO hardware") forcibly tries to find an array member which has its array index number equal to its hardware pin number and set up an array info for possible fast bitmap processing of all arrray pins belonging to that chip which also satisfy that numbering rule. Depending on array content, it may happen that consecutive array members which belong to the same chip but don't have array indexes equal to their pin hardware numbers will be split into groups, some of them processed together via the fast bitmap path, and rest of them separetely. However, applications may expect all those pins being processed together with a single call to .set_multiple() chip callback, like that was done before the change. Limit applicability of fast bitmap processing path to cases where all pins of consecutive array members starting from 0 which belong to the same chip have their hardware numbers equal to their corresponding array indexes. That should still speed up processing of applications using whole GPIO banks as I/O ports, while not breaking simultaneous manipulation of consecutive pins of the same chip which don't follow the equal numbering rule. Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-24 01:53:36 +02:00
gpiolib: Implement fast processing path in get/set array Certain GPIO descriptor arrays returned by gpio_get_array() may contain information on direct mapping of array members to pins of a single GPIO chip in hardware order. In such cases, bitmaps of values can be passed directly from/to the chip's .get/set_multiple() callbacks without wasting time on iterations. Add respective code to gpiod_get/set_array_bitmap_complex() functions. Pins not applicable for fast path are processed as before, skipping over the 'fast' ones. Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-05 23:50:08 +02:00
Documenation: driver-api: fix gpio/board.rst warning Fix markup warning: insert a blank line before the list. Documentation/driver-api/gpio/board.rst:209: WARNING: Unexpected indentation. Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Bartosz Golaszewski <bgolaszewski@baylibre.com> Cc: linux-gpio@vger.kernel.org Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-02-10 22:28:24 -08:00
gpiolib: Fix array members of same chip processed separately New code introduced by commit bf9346f5d47b ("gpiolib: Identify arrays matching GPIO hardware") forcibly tries to find an array member which has its array index number equal to its hardware pin number and set up an array info for possible fast bitmap processing of all arrray pins belonging to that chip which also satisfy that numbering rule. Depending on array content, it may happen that consecutive array members which belong to the same chip but don't have array indexes equal to their pin hardware numbers will be split into groups, some of them processed together via the fast bitmap path, and rest of them separetely. However, applications may expect all those pins being processed together with a single call to .set_multiple() chip callback, like that was done before the change. Limit applicability of fast bitmap processing path to cases where all pins of consecutive array members starting from 0 which belong to the same chip have their hardware numbers equal to their corresponding array indexes. That should still speed up processing of applications using whole GPIO banks as I/O ports, while not breaking simultaneous manipulation of consecutive pins of the same chip which don't follow the equal numbering rule. Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-24 01:53:36 +02:00
gpiolib: Implement fast processing path in get/set array Certain GPIO descriptor arrays returned by gpio_get_array() may contain information on direct mapping of array members to pins of a single GPIO chip in hardware order. In such cases, bitmaps of values can be passed directly from/to the chip's .get/set_multiple() callbacks without wasting time on iterations. Add respective code to gpiod_get/set_array_bitmap_complex() functions. Pins not applicable for fast path are processed as before, skipping over the 'fast' ones. Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-05 23:50:08 +02:00
gpiolib: Fix array members of same chip processed separately New code introduced by commit bf9346f5d47b ("gpiolib: Identify arrays matching GPIO hardware") forcibly tries to find an array member which has its array index number equal to its hardware pin number and set up an array info for possible fast bitmap processing of all arrray pins belonging to that chip which also satisfy that numbering rule. Depending on array content, it may happen that consecutive array members which belong to the same chip but don't have array indexes equal to their pin hardware numbers will be split into groups, some of them processed together via the fast bitmap path, and rest of them separetely. However, applications may expect all those pins being processed together with a single call to .set_multiple() chip callback, like that was done before the change. Limit applicability of fast bitmap processing path to cases where all pins of consecutive array members starting from 0 which belong to the same chip have their hardware numbers equal to their corresponding array indexes. That should still speed up processing of applications using whole GPIO banks as I/O ports, while not breaking simultaneous manipulation of consecutive pins of the same chip which don't follow the equal numbering rule. Cc: Jonathan Corbet <corbet@lwn.net> Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-24 01:53:36 +02:00