Commit Graph

50 Commits

Author SHA1 Message Date
Linus Walleij
22a5db98a3 Merge branch 'gpio-irq-validmask' of /home/linus/linux-pinctrl into devel 2016-09-23 14:51:18 +02:00
Mika Westerberg
79b804cb6a gpiolib: Make it possible to exclude GPIOs from IRQ domain
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>
2016-09-23 14:49:50 +02:00
Linus Walleij
65053e1a77 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>
2016-08-08 09:50:00 +02:00
Andrew Jeffery
3a0000f0ca gpio: Fix paths to GPIO driver source files
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-06-13 09:30:31 +02:00
Linus Walleij
451938d52f gpio: clarify open drain/source docs
Make the text clearer, remove reference to confusing "positive"
and "negative" and elaborate a bit.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-04-27 10:23:44 +02:00
Linus Walleij
6b5029d3ec gpio: document open drain/source behaviour
This has been a totally undocumented feature for years so add some
generic concepts and documentation about open drain/source, include
some facts on how we now support for hardware.

Cc: Michael Hennerich <michael.hennerich@analog.com>
Cc: Nicolas Saenz Julienne <nicolassaenzj@gmail.com>
Cc: H. Nikolaus Schaller <hns@goldelico.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2016-04-09 20:14:26 +02:00
Gabor Juhos
cfb7428c3d gpio: documenatation: fix GPIO_LOOKUP{,_IDX} documentation
The 'dev_id' parameter of the GPIO_LOOKUP{,_IDX} macros were removed by
commit ad824783fb ("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 16:01:51 +01:00
Masanari Iida
547d4c1078 Doc: gpio: Fix typos in Documentation/gpio
This patch fix some spelling typos found in Documentation/gpio.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-11-20 16:51:16 -07:00
Linus Torvalds
5ebe0ee802 There is a nice new document from Neil on how pathname lookups work and
some new CAN driver documentation.  Beyond that, we have kernel-doc fixes,
 a bit more work to support reproducible builds, and the usual collection of
 small fixes.
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Merge tag 'docs-for-linus' of git://git.lwn.net/linux

Pull documentation update from Jon Corbet:
 "There is a nice new document from Neil on how pathname lookups work
  and some new CAN driver documentation.  Beyond that, we have
  kernel-doc fixes, a bit more work to support reproducible builds, and
  the usual collection of small fixes"

* tag 'docs-for-linus' of git://git.lwn.net/linux: (34 commits)
  Documentation: add new description of path-name lookup.
  Documentation/vm/slub.txt: document slabinfo-gnuplot.sh
  Doc: ABI/stable: Fix typo in ABI/stable
  doc: Clarify that nmi_watchdog param is for hardlockups
  Typo correction for description in gpio document.
  DocBook: Fix kernel-doc to be case-insensitive for private:
  kernel-docs.txt: update kernelnewbies reference
  Doc:kvm: Fix typo in Doc/virtual/kvm
  Documentation/Changes: Add bc in "Current Minimal Requirements" section
  Documentation/email-clients.txt: remove trailing whitespace
  DocBook: Use a fixed encoding for output
  MAINTAINERS: The docs tree has moved
  Docs/kernel-parameters: Add earlycon devicetree usage
  SubmittingPatches: make Subject examples match the de facto standard
  Documentation: gpio: mention that <function>-gpio has been deprecated
  Documentation: cgroups: just fix a few typos
  Documentation: Update kselftest.txt
  Documentation: DMA API: Be more explicit that nents is always the same
  Documentation: Update the default value of crashkernel low
  zram: update documentation
  ...
2015-11-05 15:59:24 -08:00
Grygorii Strashko
c307b00254 gpio: add a real time compliance notes
Put in a compliance checklist.

Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-10-27 11:13:42 +01:00
Linus Walleij
4aa50b87f1 Revert "gpio: add a real time compliance checklist"
This reverts commit 677b2ff4af.
2015-10-27 11:13:18 +01:00
Linus Walleij
677b2ff4af gpio: add a real time compliance checklist
Add some information about real time compliance to the driver document.
Inspired by Grygorii Strashko's real time compliance patches.

Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-10-20 10:17:35 +02:00
Sachin Pandhare
0ea1563bc1 Typo correction for description in gpio document.
Corrected Documentation/gpio/sysfs.txt for typos and wording.
typos: syfs -> sysfs, manges -> manages
wording: entry -> entries

Signed-off-by: Sachin Pandhare <sachinpandhare@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-10-11 15:39:01 -06:00
Javier Martinez Canillas
2b71920e60 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:

dd34c37aa3 ("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>
2015-09-24 15:56:13 -06:00
Javier Martinez Canillas
ae80d64ee8 Documentation: gpio: Explain that <function>-gpio is also supported
The GPIO documentation mentions that GPIOs are mapped by defining a
<function>-gpios property in the consumer device's node but a -gpio
sufix is also supported after commit:

dd34c37aa3 ("gpio: of: Allow -gpio suffix for property names")

Update the documentation to match the implementation.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-09-14 09:12:03 +02:00
Dirk Behme
87e77e46c6 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>
2015-09-14 09:12:03 +02:00
Dirk Behme
69de52ba32 Documentation: gpio: board: add flags parameter to gpiod_get*() functions
With commit 39b2bbe3d7 ("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>
2015-09-14 09:12:03 +02:00
Dirk Behme
ac49fbd1f9 Documentation: gpio: consumer: describe active low property
I've been searching for any documentation of 'the active-low property of a GPIO'
already mentioned in this documenation. But couldn't find any. Add it.

Sigend-off-by: Dirk Behme <dirk.behme@gmail.com>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
[Spelling, grammar fixes]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-08-17 10:38:52 +02:00
Linus Walleij
c21cde6fe1 gpio: document interaction with other subsystems
Now I am very fed up with people reinventing kernel wheels in
userspace "just because they can" (read, sysfs). Put in a angry
blurb in sysfs doc and put in a new file with pointers to other
subsystem drivers utilizing GPIOs.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-07-21 11:39:32 +02:00
Linus Torvalds
1e467e68e5 Documentation updates for 4.2
The main thing here is Ingo's big subdirectory documenting feature support
 for each architecture.  Beyond that, it's the usual pile of fixes, tweaks,
 and small additions.
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Merge tag 'docs-for-linus' of git://git.lwn.net/linux-2.6

Pull documentation updates from Jonathan Corbet:
 "The main thing here is Ingo's big subdirectory documenting feature
  support for each architecture.  Beyond that, it's the usual pile of
  fixes, tweaks, and small additions"

* tag 'docs-for-linus' of git://git.lwn.net/linux-2.6: (79 commits)
  doc:md: fix typo in md.txt.
  Documentation/mic/mpssd: don't build x86 userspace when cross compiling
  Documentation/prctl: don't build tsc tests when cross compiling
  Documentation/vDSO: don't build tests when cross compiling
  Doc:ABI/testing: Fix typo in sysfs-bus-fcoe
  Doc: Docbook: Change wikipedia's URL from http to https in scsi.tmpl
  Doc: Change wikipedia's URL from http to https
  Documentation/kernel-parameters: add missing pciserial to the earlyprintk
  Doc:pps: Fix typo in pps.txt
  kbuild : Fix documentation of INSTALL_HDR_PATH
  Documentation: filesystems: updated struct file_operations documentation in vfs.txt
  kbuild: edit explanation of clean-files variable
  Doc: ja_JP: Fix typo in HOWTO
  Move freefall program from Documentation/ to tools/
  Documentation: ARM: EXYNOS: Describe boot loaders interface
  Doc:nfc: Fix typo in nfc-hci.txt
  vfs: Minor documentation fix
  Doc: networking: txtimestamp: fix printf format warning
  Documentation, intel_pstate: Improve legacy mode internal governors description
  Documentation: extend use case for EXPORT_SYMBOL_GPL()
  ...
2015-06-24 20:01:36 -07:00
Rojhalat Ibrahim
e2bfba4185 fix documentation after renaming gpiod_set_array to gpiod_set_array_value
Patch "gpiolib: rename gpiod_set_array to gpiod_set_array_value" omitted
to also change the function names in the documentation. Let's fix that.

Signed-off-by: Rojhalat Ibrahim <imr@rtschenk.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-06-04 10:46:43 +02:00
Geert Uytterhoeven
cbfa2c5281 gpiolib: Grammar s/an negative/a negative/
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-05-22 09:31:15 -06:00
Johan Hovold
166a85e442 gpio: remove gpiod_sysfs_set_active_low
Remove gpiod_sysfs_set_active_low (and gpio_sysfs_set_active_low) which
allowed code to change the polarity of a gpio line even after it had
been exported through sysfs.

Drivers should not care, and generally does not know, about gpio-line
polarity which is a hardware feature that needs to be described by
firmware.

It is currently possible to define gpio-line polarity in device-tree and
acpi firmware or using platform data. Userspace can also change the
polarity through sysfs.

Note that drivers using the legacy gpio interface could still use
GPIOF_ACTIVE_LOW to change the polarity before exporting the gpio.

There are no in-kernel users of this interface.

Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Harry Wei <harryxiyou@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@zh-kernel.org
Cc: linux-arch@vger.kernel.org
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-05-12 10:46:53 +02:00
Linus Torvalds
d6a24d0640 The documentation tree update for 4.1. Numerous fixes, the overdue removal
of the i2o docs, some new Chinese translations, and, hopefully, the README
 fix that will end the flow of identical patches to that file.
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Merge tag 'docs-for-linus' of git://git.lwn.net/linux-2.6

Pull documentation updates from Jonathan Corbet:
 "Numerous fixes, the overdue removal of the i2o docs, some new Chinese
  translations, and, hopefully, the README fix that will end the flow of
  identical patches to that file"

* tag 'docs-for-linus' of git://git.lwn.net/linux-2.6: (34 commits)
  Documentation/memcg: update memcg/kmem status
  Documentation: blackfin: Makefile: Typo building issue
  Documentation/vm/pagemap.txt: correct location of page-types tool
  Documentation/memory-barriers.txt: typo fix
  doc: Add guest_nice column to example output of `cat /proc/stat'
  Documentation/kernel-parameters: Move "eagerfpu" to its right place
  Documentation: gpio: Update ACPI part of the document to mention _DSD
  docs/completion.txt: Various tweaks and corrections
  doc: completion: context, scope and language fixes
  Documentation:Update Documentation/zh_CN/arm64/memory.txt
  Documentation:Update Documentation/zh_CN/arm64/booting.txt
  Documentation: Chinese translation of arm64/legacy_instructions.txt
  DocBook media: fix broken EIA hyperlink
  Documentation: tweak the maintainers entry
  README: Change gzip/bzip2 to xz compression format
  README: Update version number reference
  doc:pci: Fix typo in Documentation/PCI
  Documentation: drm: Use '->' when describing access through pointers.
  Documentation: Remove mentioning of block barriers
  Documentation/email-clients.txt: Fix one grammar mistake, add extra info about TB
  ...
2015-04-18 11:10:49 -04:00
Mika Westerberg
cfc507648c 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>
2015-04-04 15:20:27 +02:00
Rojhalat Ibrahim
de3b696542 extend documentation for gpiod_set_array() functions
Extend the documentation for the gpiod_set_array() functions and elaborate
a bit on possible use cases.

Signed-off-by: Rojhalat Ibrahim <imr@rtschenk.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-03-09 17:38:49 +01:00
Rojhalat Ibrahim
331758eef8 gpiolib: add devm_gpiod_get_array and devm_gpiod_put_array functions
Add device managed variants of gpiod_get_array() / gpiod_put_array()
functions for conveniently obtaining and disposing of an entire array
of GPIOs with one function call.

Signed-off-by: Rojhalat Ibrahim <imr@rtschenk.de>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-03-05 09:55:42 +01:00
Rojhalat Ibrahim
6685852732 gpiolib: add gpiod_get_array and gpiod_put_array functions
Introduce new functions for conveniently obtaining and disposing of
an entire array of GPIOs with one function call.

ACPI parts tested by Mika Westerberg, DT parts tested by Rojhalat
Ibrahim.

Change log:
v5: move the ACPI functions to gpiolib-acpi.c
v4: - use shorter names for members of struct gpio_descs
    - rename lut_gpio_count to platform_gpio_count for clarity
    - add check for successful memory allocation
    - use ERR_CAST()
v3: - rebase on current linux-gpio devel branch
    - fix ACPI GPIO counting
    - allow for zero-sized arrays
    - make the flags argument mandatory for the new functions
    - clarify documentation
v2: change interface

Suggested-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Rojhalat Ibrahim <imr@rtschenk.de>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Rojhalat Ibrahim <imr@rtschenk.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-03-05 09:52:28 +01:00
Fabio Estevam
4f7d45596e gpio: board.txt: Fix the gpio name example
As explained in this file:

"GPIOs mappings are defined in the consumer device's node, in a property named
<function>-gpios"

So fix the example to match the convention.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-01-28 11:14:00 -07:00
Linus Torvalds
980f3c344f This is the bulk of GPIO changes for the v3.19 series:
- A new API that allows setting more than one GPIO at the
   time. This is implemented for the new descriptor-based
   API only and makes it possible to e.g. toggle a clock and
   data line at the same time, if the hardware can do this
   with a single register write. Both consumers and drivers
   need new calls, and the core will fall back to driving
   individual lines where needed. Implemented for the MPC8xxx
   driver initially.
 - Patched the mdio-mux-gpio and the serial mctrl driver
   that drives modems to use the new multiple-setting API
   to set several signals simultaneously.
 - Get rid of the global GPIO descriptor array, and instead
   allocate descriptors dynamically for each GPIO on a certain
   GPIO chip. This moves us closer to getting rid of the
   limitation of using the global, static GPIO numberspace.
 - New driver and device tree bindings for 74xx ICs.
 - New driver and device tree bindings for the VF610 Vybrid.
 - Support the RCAR r8a7793 and r8a7794.
 - Guidelines for GPIO device tree bindings trying to get
   things a bit more strict with the advent of combined
   device properties.
 - Suspend/resume support for the MVEBU driver.
 - A slew of minor fixes and improvements.
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Merge tag 'gpio-v3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull take two of the GPIO updates:
 "Same stuff as last time, now with a fixup patch for the previous
  compile error plus I ran a few extra rounds of compile-testing.

  This is the bulk of GPIO changes for the v3.19 series:

   - A new API that allows setting more than one GPIO at the time.  This
     is implemented for the new descriptor-based API only and makes it
     possible to e.g. toggle a clock and data line at the same time, if
     the hardware can do this with a single register write.  Both
     consumers and drivers need new calls, and the core will fall back
     to driving individual lines where needed.  Implemented for the
     MPC8xxx driver initially

   - Patched the mdio-mux-gpio and the serial mctrl driver that drives
     modems to use the new multiple-setting API to set several signals
     simultaneously

   - Get rid of the global GPIO descriptor array, and instead allocate
     descriptors dynamically for each GPIO on a certain GPIO chip.  This
     moves us closer to getting rid of the limitation of using the
     global, static GPIO numberspace

   - New driver and device tree bindings for 74xx ICs

   - New driver and device tree bindings for the VF610 Vybrid

   - Support the RCAR r8a7793 and r8a7794

   - Guidelines for GPIO device tree bindings trying to get things a bit
     more strict with the advent of combined device properties

   - Suspend/resume support for the MVEBU driver

   - A slew of minor fixes and improvements"

* tag 'gpio-v3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (33 commits)
  gpio: mcp23s08: fix up compilation error
  gpio: pl061: document gpio-ranges property for bindings file
  gpio: pl061: hook request if gpio-ranges avaiable
  gpio: mcp23s08: Add option to configure IRQ output polarity as active high
  gpio: fix deferred probe detection for legacy API
  serial: mctrl_gpio: use gpiod_set_array function
  mdio-mux-gpio: Use GPIO descriptor interface and new gpiod_set_array function
  gpio: remove const modifier from gpiod_get_direction()
  gpio: remove gpio_descs global array
  gpio: mxs: implement get_direction callback
  gpio: em: Use dynamic allocation of GPIOs
  gpio: Check if base is positive before calling gpio_is_valid()
  gpio: mcp23s08: Add simple IRQ support for SPI devices
  gpio: mcp23s08: request a shared interrupt
  gpio: mcp23s08: Do not free unrequested interrupt
  gpio: rcar: Add r8a7793 and r8a7794 support
  gpio-mpc8xxx: add mpc8xxx_gpio_set_multiple function
  gpiolib: allow simultaneous setting of multiple GPIO outputs
  gpio: mvebu: add suspend/resume support
  gpio: gpio-davinci: remove duplicate check on resource
  ..
2014-12-14 14:05:05 -08:00
Rojhalat Ibrahim
5f42424354 gpiolib: allow simultaneous setting of multiple GPIO outputs
Introduce new functions gpiod_set_array & gpiod_set_raw_array to the consumer
interface which allow setting multiple outputs with just one function call.
Also add an optional set_multiple function to the driver interface. Without an
implementation of that function in the chip driver outputs are set
sequentially.

Implementing the set_multiple function in a chip driver allows for:
- Improved performance for certain use cases. The original motivation for this
  was the task of configuring an FPGA. In that specific case, where 9 GPIO
  lines have to be set many times, configuration time goes down from 48 s to
  20 s when using the new function.
- Simultaneous glitch-free setting of multiple pins on any kind of parallel
  bus attached to GPIOs provided they all reside on the same chip and bank.

Limitations:
  Performance is only improved for normal high-low outputs. Open drain and
  open source outputs are always set separately from each other. Those kinds
  of outputs could probably be accelerated in a similar way if we could
  forgo the error checking when setting GPIO directions.

Change log:
  v6: - rebase on current linux-gpio devel branch
  v5: - check can_sleep property per chip
      - remove superfluous checks
      - supplement documentation
  v4: - add gpiod_set_array function for setting logical values
      - change interface of the set_multiple driver function to use
        unsigned long as type for the bit fields
      - use generic bitops (which also use unsigned long for bit fields)
      - do not use ARCH_NR_GPIOS any more
  v3: - add documentation
      - change commit message
  v2: - use descriptor interface
      - allow arbitrary groups of GPIOs spanning multiple chips

Signed-off-by: Rojhalat Ibrahim <imr@rtschenk.de>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-11-27 15:01:18 +01:00
Rafael J. Wysocki
e36d453e98 ACPI / GPIO: Document ACPI GPIO mappings API
Document the previously introduced method that can be used by device
drivers to provide the GPIO subsystem with mappings between GPIO names
(connection IDs) and GpioIo()/GpioInt() resources in _CRS.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
2014-11-04 21:58:24 +01:00
Alexandre Courbot
e3a2e87893 gpio: rename gpio_lock_as_irq to gpiochip_lock_as_irq
This function actually operates on a gpio_chip, so its prefix should
reflect that fact for consistency with other functions defined in
gpio/driver.h.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-10-28 17:30:59 +01:00
Linus Torvalds
ea584595fc This is the bulk of GPIO changes for the v3.18 development
cycle:
 
 - Increase the default ARCH_NR_GPIO from 256 to 512. This
   was done to avoid having a custom <asm/gpio.h> header for
   the x86 architecture - GPIO is custom and complicated
   enough as it is already! We want to move to a radix to
   store the descriptors going forward, and finally get rid
   of this fixed array size altogether.
 
 - Endgame patching of the gpio_remove() semantics initiated
   by Abdoulaye Berthe. It is not accepted by the system that
   the removal of a GPIO chip fails during e.g. reboot or
   shutdown, and therefore the return value has now painfully
   been refactored away. For special cases like GPIO expanders
   on a hot-pluggable bus like USB, we may later add some
   gpiochip_try_remove() call, but for the cases we have now,
   return values are moot.
 
 - Some incremental refactoring of the gpiolib core and ACPI
   GPIO library for more descriptor usage.
 
 - Refactor the chained IRQ handler set-up method to handle
   also threaded, nested interrupts and set up the parent IRQ
   correctly. Switch STMPE and TC3589x drivers to use this
   registration method.
 
 - Add a .irq_not_threaded flag to the struct gpio_chip, so
   that also GPIO expanders that block but are still not
   using threaded IRQ handlers.
 
 - New drivers for the ARM64 X-Gene SoC GPIO controller.
 
 - The syscon GPIO driver has been improved to handle the
   "DSP GPIO" found on the TI Keystone 2 SoC:s.
 
 - ADNP driver switched to use gpiolib irqchip helpers.
 
 - Refactor the DWAPB driver to support being instantiated
   from and MFD cell (platform device).
 
 - Incremental feature improvement in the Zynq, MCP23S08,
   DWAPB, OMAP, Xilinx and Crystalcove drivers.
 
 - Various minor fixes.
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Merge tag 'gpio-v3.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO changes from Linus Walleij:
 "This is the bulk of GPIO changes for the v3.18 development cycle:

   - Increase the default ARCH_NR_GPIO from 256 to 512.  This was done
     to avoid having a custom <asm/gpio.h> header for the x86
     architecture - GPIO is custom and complicated enough as it is
     already! We want to move to a radix to store the descriptors going
     forward, and finally get rid of this fixed array size altogether.

   - Endgame patching of the gpio_remove() semantics initiated by
     Abdoulaye Berthe.  It is not accepted by the system that the
     removal of a GPIO chip fails during eg reboot or shutdown, and
     therefore the return value has now painfully been refactored away.
     For special cases like GPIO expanders on a hot-pluggable bus like
     USB, we may later add some gpiochip_try_remove() call, but for the
     cases we have now, return values are moot.

   - Some incremental refactoring of the gpiolib core and ACPI GPIO
     library for more descriptor usage.

   - Refactor the chained IRQ handler set-up method to handle also
     threaded, nested interrupts and set up the parent IRQ correctly.
     Switch STMPE and TC3589x drivers to use this registration method.

   - Add a .irq_not_threaded flag to the struct gpio_chip, so that also
     GPIO expanders that block but are still not using threaded IRQ
     handlers.

   - New drivers for the ARM64 X-Gene SoC GPIO controller.

   - The syscon GPIO driver has been improved to handle the "DSP GPIO"
     found on the TI Keystone 2 SoC:s.

   - ADNP driver switched to use gpiolib irqchip helpers.

   - Refactor the DWAPB driver to support being instantiated from and
     MFD cell (platform device).

   - Incremental feature improvement in the Zynq, MCP23S08, DWAPB, OMAP,
     Xilinx and Crystalcove drivers.

   - Various minor fixes"

* tag 'gpio-v3.18-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (52 commits)
  gpio: pch: Build context save/restore only for PM
  pinctrl: abx500: get rid of unused variable
  gpio: ks8695: fix 'else should follow close brace '}''
  gpio: stmpe: add verbose debug code
  gpio: stmpe: fix up interrupt enable logic
  gpio: staticize xway_stp_init()
  gpio: handle also nested irqchips in the chained handler set-up
  gpio: set parent irq on chained handlers
  gpiolib: irqchip: use irq_find_mapping while removing irqchip
  gpio: crystalcove: support virtual GPIO
  pinctrl: bcm281xx: make Kconfig dependency more strict
  gpio: kona: enable only on BCM_MOBILE or for compile testing
  gpio, bcm-kona, LLVMLinux: Remove use of __initconst
  gpio: Fix ngpio in gpio-xilinx driver
  gpio: dwapb: fix pointer to integer cast
  gpio: xgene: Remove unneeded #ifdef CONFIG_OF guard
  gpio: xgene: Remove unneeded forward declation for struct xgene_gpio
  gpio: xgene: Fix missing spin_lock_init()
  gpio: ks8695: fix switch case indentation
  gpiolib: add irq_not_threaded flag to gpio_chip
  ...
2014-10-09 14:58:15 -04:00
Linus Walleij
3f97d5fcf9 gpio: handle also nested irqchips in the chained handler set-up
To unify how we connect cascaded IRQ chips to parent IRQs, if
NULL us passed as handler to the gpiochip_set_chained_irqchip()
function, assume the chips is nested rather than chained, and
we still get the parent set up correctly by way of this function
call.

Alter the drivers for tc3589x and stmpe to use this to set up
their chained handlers as a demonstration of the usage.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-09-26 14:39:08 +02:00
Alexandre Courbot
abdc08a3a2 gpio: change gpiochip_request_own_desc() prototype
The current prototype of gpiochip_request_own_desc() requires to obtain
a pointer to a descriptor. This is in contradiction to all other GPIO
request schemes, and imposes an extra step of obtaining a descriptor to
drivers. Most drivers actually cannot even perform that step since the
function that does it (gpichip_get_desc()) is gpiolib-private.

Change gpiochip_request_own_desc() to return a descriptor from a
(chip, hwnum) tuple and update users of this function (currently
gpiolib-acpi only).

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-08-29 08:58:34 +02:00
Alexandre Courbot
1b11a9b9e0 Documentation: gpio: documentation for optional getters functions
Add a mention about the _optional variants of (devm_)gpiod_get*().

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-08-29 08:53:53 +02:00
Alexandre Courbot
39b2bbe3d7 gpio: add flags argument to gpiod_get*() functions
The huge majority of GPIOs have their direction and initial value set
right after being obtained by one of the gpiod_get() functions. The
integer GPIO API had gpio_request_one() that took a convenience flags
parameter allowing to specify an direction and value applied to the
returned GPIO. This feature greatly simplifies client code and ensures
errors are always handled properly.

A similar feature has been requested for the gpiod API. Since setting
the direction of a GPIO is so often the very next action done after
obtaining its descriptor, we prefer to extend the existing functions
instead of introducing new functions that would raise the
number of gpiod getters to 16 (!).

The drawback of this approach is that all gpiod clients need to be
updated. To limit the pain, temporary macros are introduced that allow
gpiod_get*() to be called with or without the extra flags argument. They
will be removed once all consumer code has been updated.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-07-28 12:28:05 +02:00
Linus Walleij
0a6d315827 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>
2014-07-28 12:23:35 +02:00
Guenter Roeck
f7d4ad98fd gpiolib: Export gpiochip_request_own_desc and gpiochip_free_own_desc
Both functions were introduced to let gpio drivers request their own
gpio pins. Without exporting the functions, this can however only be
used by gpio drivers built into the kernel.

Secondary impact is that the functions can not currently be used by
platform initialization code associated with the gpio-pca953x driver.
This code permits auto-export of gpio pins through platform data, but
if this functionality is used, the module can no longer be unloaded due
to the problem solved with the introduction of gpiochip_request_own_desc
and gpiochip_free_own_desc.

Export both function so they can be used from modules and from
platform initialization code.

Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-07-24 10:25:00 +02:00
Alexandre Courbot
d74be6dfea gpio: remove gpiod_lock/unlock_as_irq()
gpio_lock/unlock_as_irq() are working with (chip, offset) arguments and
are thus not using the old integer namespace. Therefore, there is no
reason to have gpiod variants of these functions working with
descriptors, especially since the (chip, offset) tuple is more suitable
to the users of these functions (GPIO drivers, whereas GPIO descriptors
are targeted at GPIO consumers).

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-07-23 17:43:24 +02:00
Linus Torvalds
1aacb90eaa Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial into next
Pull trivial tree changes from Jiri Kosina:
 "Usual pile of patches from trivial tree that make the world go round"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (23 commits)
  staging: go7007: remove reference to CONFIG_KMOD
  aic7xxx: Remove obsolete preprocessor define
  of: dma: doc fixes
  doc: fix incorrect formula to calculate CommitLimit value
  doc: Note need of bc in the kernel build from 3.10 onwards
  mm: Fix printk typo in dmapool.c
  modpost: Fix comment typo "Modules.symvers"
  Kconfig.debug: Grammar s/addition/additional/
  wimax: Spelling s/than/that/, wording s/destinatary/recipient/
  aic7xxx: Spelling s/termnation/termination/
  arm64: mm: Remove superfluous "the" in comment
  of: Spelling s/anonymouns/anonymous/
  dma: imx-sdma: Spelling s/determnine/determine/
  ath10k: Improve grammar in comments
  ath6kl: Spelling s/determnine/determine/
  of: Improve grammar for of_alias_get_id() documentation
  drm/exynos: Spelling s/contro/control/
  radio-bcm2048.c: fix wrong overflow check
  doc: printk-formats: do not mention casts for u64/s64
  doc: spelling error changes
  ...
2014-06-04 08:50:34 -07:00
Carlos Garcia
c98be0c96d doc: spelling error changes
Fixed multiple spelling errors.

Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Carlos E. Garcia <carlos@cgarcia.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2014-05-05 15:32:05 +02:00
Linus Walleij
90887db883 gpio: document gpio irqchips a bit more, describe helpers
This adds some documentation about the GPIO irqchips, what types
exist etc.

Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-04-28 12:35:07 -07:00
Philipp Zabel
ef70bbe1aa gpio: make gpiod_direction_output take a logical value
The documentation was not clear about whether
gpio_direction_output should take a logical value or the physical
level on the output line, i.e. whether the ACTIVE_LOW status
would be taken into account.

This converts gpiod_direction_output to use the logical level
and adds a new gpiod_direction_output_raw for the raw value.

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-02-07 09:47:02 +01:00
Linus Walleij
99adc05948 gpio: document how to make combined GPIO+irqchip drivers
Write a few words on how GPIO drivers supplying an irqchip should
be written.

Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2014-02-03 09:11:57 +01:00
Alexandre Courbot
2a3cf6a359 gpiolib: return -ENOENT if no GPIO mapping exists
Some devices drivers make use of optional GPIO parameters. For such
drivers, it is important to discriminate between the case where no
GPIO mapping has been defined for the function they are requesting, and
the case where a mapping exists but an error occured while resolving it
or when acquiring the GPIO.

This patch changes the family of gpiod_get() functions such that they
will return -ENOENT if and only if no GPIO mapping is defined for the
requested function. Other error codes are used when an actual error
occured during the GPIO resolution.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-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>
2013-12-12 19:33:59 +01:00
Alexandre Courbot
ad824783fb 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>
2013-12-09 14:05:51 +01:00
Alexandre Courbot
56a39aac59 Documentation: gpiolib: add 00-INDEX file
Give a short overview of the various GPIO documentation files.

Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2013-12-03 13:10:48 +01:00
Alexandre Courbot
fd8e198cfc 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>
2013-11-25 09:02:30 +01:00