Commit Graph

181 Commits

Author SHA1 Message Date
Linus Torvalds 43c95d3694 This is the bulk of pin control changes for the v5.3 kernel
cycle:
 
 Core changes:
 
 - Device links can optionally be added between a pin control
   producer and its consumers. This will affect how the system
   power management is handled: a pin controller will not suspend
   before all of its consumers have been suspended. This was
   necessary for the ST Microelectronics STMFX expander and
   need to be tested on other systems as well: it makes sense
   to make this default in the long run. Right now it is
   opt-in per driver.
 
 - Drive strength can be specified in microamps. With decreases
   in silicon technology, milliamps isn't granular enough, let's
   make it possible to select drive strengths in microamps. Right
   now the Meson (AMlogic) driver needs this.
 
 New drivers:
 
 - New subdriver for the Tegra 194 SoC.
 
 - New subdriver for the Qualcomm SDM845.
 
 - New subdriver for the Qualcomm SM8150.
 
 - New subdriver for the Freescale i.MX8MN (Freescale is now a
   product line of NXP).
 
 - New subdriver for Marvell MV98DX1135.
 
 Driver improvements:
 
 - The Bitmain BM1880 driver now supports pin config in
   addition to muxing.
 
 - The Qualcomm drivers can now reserve some GPIOs as taken
   aside and not usable for users. This is used in ACPI systems
   to take out some GPIO lines used by the BIOS so that
   noone else (neither kernel nor userspace) will play with them
   by mistake and crash the machine.
 
 - A slew of refurbishing around the Aspeed drivers (board
   management controllers for servers) in preparation for the
   new Aspeed AST2600 SoC.
 
 - A slew of improvements over the SH PFC drivers as usual.
 
 - Misc cleanups and fixes.
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Merge tag 'pinctrl-v5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl

Pull pin control updates from Linus Walleij:
 "This is the bulk of pin control changes for the v5.3 kernel cycle:

  Core changes:

   - Device links can optionally be added between a pin control producer
     and its consumers. This will affect how the system power management
     is handled: a pin controller will not suspend before all of its
     consumers have been suspended.

     This was necessary for the ST Microelectronics STMFX expander and
     need to be tested on other systems as well: it makes sense to make
     this default in the long run.

     Right now it is opt-in per driver.

   - Drive strength can be specified in microamps. With decreases in
     silicon technology, milliamps isn't granular enough, let's make it
     possible to select drive strengths in microamps.

     Right now the Meson (AMlogic) driver needs this.

  New drivers:

   - New subdriver for the Tegra 194 SoC.

   - New subdriver for the Qualcomm SDM845.

   - New subdriver for the Qualcomm SM8150.

   - New subdriver for the Freescale i.MX8MN (Freescale is now a product
     line of NXP).

   - New subdriver for Marvell MV98DX1135.

  Driver improvements:

   - The Bitmain BM1880 driver now supports pin config in addition to
     muxing.

   - The Qualcomm drivers can now reserve some GPIOs as taken aside and
     not usable for users. This is used in ACPI systems to take out some
     GPIO lines used by the BIOS so that noone else (neither kernel nor
     userspace) will play with them by mistake and crash the machine.

   - A slew of refurbishing around the Aspeed drivers (board management
     controllers for servers) in preparation for the new Aspeed AST2600
     SoC.

   - A slew of improvements over the SH PFC drivers as usual.

   - Misc cleanups and fixes"

* tag 'pinctrl-v5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (106 commits)
  pinctrl: aspeed: Strip moved macros and structs from private header
  pinctrl: aspeed: Fix missed include
  pinctrl: baytrail: Use GENMASK() consistently
  pinctrl: baytrail: Re-use data structures from pinctrl-intel.h
  pinctrl: baytrail: Use defined macro instead of magic in byt_get_gpio_mux()
  pinctrl: qcom: Add SM8150 pinctrl driver
  dt-bindings: pinctrl: qcom: Add SM8150 pinctrl binding
  dt-bindings: pinctrl: qcom: Document missing gpio nodes
  pinctrl: aspeed: Add implementation-related documentation
  pinctrl: aspeed: Split out pinmux from general pinctrl
  pinctrl: aspeed: Clarify comment about strapping W1C
  pinctrl: aspeed: Correct comment that is no longer true
  MAINTAINERS: Add entry for ASPEED pinctrl drivers
  dt-bindings: pinctrl: aspeed: Convert AST2500 bindings to json-schema
  dt-bindings: pinctrl: aspeed: Convert AST2400 bindings to json-schema
  dt-bindings: pinctrl: aspeed: Split bindings document in two
  pinctrl: qcom: Add irq_enable callback for msm gpio
  pinctrl: madera: Fixup SPDX headers
  pinctrl: qcom: sdm845: Fix CONFIG preprocessor guard
  pinctrl: tegra: Add bitmask support for parked bits
  ...
2019-07-13 15:02:27 -07:00
Geert Uytterhoeven f99d479bcb gpiolib: Document new gpio_chip.init_valid_mask field
A new field init_valid_mask was added to struct gpio_chip, but it was
not documented.

Fixes: f8ec92a9f6 ("gpiolib: Add init_valid_mask exported function")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20190701142650.25122-1-geert+renesas@glider.be
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-07-04 09:33:57 +02:00
Enrico Weigelt f310f2eff7 gpio: Add comments on #if/#else/#endif
Improve readability a bit by commenting #if/#else/#endif statements
with the checked preprocessor symbols.

Signed-off-by: Enrico Weigelt <info@metux.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-06-27 15:56:50 +01:00
Linus Walleij 4892d3a6a0 gpio: Drop the parent_irq from gpio_irq_chip
We already have an array named "parents" so instead
of letting one point to the other, simply allocate a
dynamic array to hold the parents, just one if desired
and drop the number of members in gpio_irq_chip by
1. Rename gpiochip to gc in the process.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-06-14 10:16:16 +02:00
Enrico Weigelt d664c43958 gpio: Fix build warnings on undefined struct pinctrl_dev
This fixes the warnings:

* include/linux/gpio.h:254:11: warning: 'struct pinctrl_dev' declared
  inside parameter list will not be visible outside of this definition
  or declaration
* include/linux/gpio/driver.h:602:11: warning: 'struct pinctrl_dev'
  declared inside parameter list will not be visible outside of this
  definition or declaration

Fixes: 78b99577b3 ("pinctrl: remove unused pin_is_valid()")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Enrico Weigelt <info@metux.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-06-13 02:38:28 +02:00
Linus Walleij 5923ea6c2c gpio: pass lookup and descriptor flags to request_own
When a gpio_chip wants to request a descriptor from itself
using gpiochip_request_own_desc() it needs to be able to specify
fully how to use the descriptor, notably line inversion
semantics. The workaround in the gpiolib.c can be removed
and cases (such as SPI CS) where we need at times to request
a GPIO with line inversion semantics directly on a chip for
workarounds, can be fully supported with this call.

Fix up some users of the API that weren't really using the
last flag to set up the line as input or output properly
but instead just calling direction setting explicitly
after requesting the line.

Cc: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-06-07 23:20:23 +02:00
Linus Torvalds 8148c17b17 This is the bulk of the GPIO changes for the v5.2 kernel cycle:
Core changes:
 - The gpiolib MMIO driver has been enhanced to handle two direction
   registers, i.e. one register to set lines as input and one register
   to set lines as output. It turns out some silicon engineer thinks
   the ability to configure a line as input and output at the same
   time makes sense, this can be debated but includes a lot of analog
   electronics reasoning, and the registers are there and need to
   be handled consistently. Unsurprisingly, we enforce the lines to
   be either inputs or outputs in such schemes.
 - Send in the proper argument value to .set_config() dispatched to
   the pin control subsystem. Nobody used it before, now someone
   does, so fix it to work as expected.
 - The ACPI gpiolib portions can now handle pin bias setting (pull up
   or pull down). This has been in the ACPI spec for years and we
   finally have it properly integrated with Linux GPIOs. It was based
   on an observation from Andy Schevchenko that Thomas Petazzoni's
   changes to the core for biasing the PCA950x GPIO expander actually
   happen to fit hand-in-glove with what the ACPI core needed.
   Such nice synergies happen sometimes.
 
 New drivers:
 - A new driver for the Mellanox BlueField GPIO controller. This is
   using 64bit MMIO registers and can configure lines as inputs
   and outputs at the same time and after improving the MMIO library
   we handle it just fine. Interesting.
 - A new IXP4xx proper gpiochip driver with hierarchical interrupts
   should be coming in from the ARM SoC tree as well.
 
 Driver enhancements:
 - The PCA053x driver handles the CAT9554 GPIO expander.
 - The PCA053x driver handles the NXP PCAL6416 GPIO expander.
 - Wake-up support on PCA053x GPIO lines.
 - OMAP now does a nice asynchronous IRQ handling on wake-ups by
   letting everything wake up on edges, and this makes runtime PM
   work as expected too.
 
 Misc:
 - Several cleanups such as devres fixes.
 - Get rid of some languager comstructs that cause problems when
   compiling with LLVMs clang.
 - Documentation review and update.
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Merge tag 'gpio-v5.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull gpio updates from Linus Walleij:
 "This is the bulk of the GPIO changes for the v5.2 kernel cycle. A bit
  later than usual because I was ironing out my own mistakes. I'm
  holding some stuff back for the next kernel as a result, and this
  should be a healthy and well tested batch.

  Core changes:

   - The gpiolib MMIO driver has been enhanced to handle two direction
     registers, i.e. one register to set lines as input and one register
     to set lines as output. It turns out some silicon engineer thinks
     the ability to configure a line as input and output at the same
     time makes sense, this can be debated but includes a lot of analog
     electronics reasoning, and the registers are there and need to be
     handled consistently. Unsurprisingly, we enforce the lines to be
     either inputs or outputs in such schemes.

   - Send in the proper argument value to .set_config() dispatched to
     the pin control subsystem. Nobody used it before, now someone does,
     so fix it to work as expected.

   - The ACPI gpiolib portions can now handle pin bias setting (pull up
     or pull down). This has been in the ACPI spec for years and we
     finally have it properly integrated with Linux GPIOs. It was based
     on an observation from Andy Schevchenko that Thomas Petazzoni's
     changes to the core for biasing the PCA950x GPIO expander actually
     happen to fit hand-in-glove with what the ACPI core needed. Such
     nice synergies happen sometimes.

  New drivers:

   - A new driver for the Mellanox BlueField GPIO controller. This is
     using 64bit MMIO registers and can configure lines as inputs and
     outputs at the same time and after improving the MMIO library we
     handle it just fine. Interesting.

   - A new IXP4xx proper gpiochip driver with hierarchical interrupts
     should be coming in from the ARM SoC tree as well.

  Driver enhancements:

   - The PCA053x driver handles the CAT9554 GPIO expander.

   - The PCA053x driver handles the NXP PCAL6416 GPIO expander.

   - Wake-up support on PCA053x GPIO lines.

   - OMAP now does a nice asynchronous IRQ handling on wake-ups by
     letting everything wake up on edges, and this makes runtime PM work
     as expected too.

  Misc:

   - Several cleanups such as devres fixes.

   - Get rid of some languager comstructs that cause problems when
     compiling with LLVMs clang.

   - Documentation review and update"

* tag 'gpio-v5.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (85 commits)
  gpio: Update documentation
  docs: gpio: convert docs to ReST and rename to *.rst
  gpio: sch: Remove write-only core_base
  gpio: pxa: Make two symbols static
  gpiolib: acpi: Respect pin bias setting
  gpiolib: acpi: Add acpi_gpio_update_gpiod_lookup_flags() helper
  gpiolib: acpi: Set pin value, based on bias, more accurately
  gpiolib: acpi: Change type of dflags
  gpiolib: Introduce GPIO_LOOKUP_FLAGS_DEFAULT
  gpiolib: Make use of enum gpio_lookup_flags consistent
  gpiolib: Indent entry values of enum gpio_lookup_flags
  gpio: pca953x: add support for pca6416
  dt-bindings: gpio: pca953x: document the nxp,pca6416
  gpio: pca953x: add pcal6416 to the of_device_id table
  gpio: gpio-omap: Remove conditional pm_runtime handling for GPIO interrupts
  gpio: gpio-omap: configure edge detection for level IRQs for idle wakeup
  tracing: stop making gpio tracing configurable
  gpio: pca953x: Configure wake-up path when wake-up is enabled
  gpio: of: Optimize quirk checks
  gpio: mmio: Drop bgpio_dir_inverted
  ...
2019-05-11 10:54:43 -04:00
Andy Shevchenko 2d6c06f5a4 gpiolib: Introduce GPIO_LOOKUP_FLAGS_DEFAULT
Since GPIO library operates with enumerator when it's subject to handle
the GPIO lookup flags, it will be better to clearly see what default means.

Thus, introduce GPIO_LOOKUP_FLAGS_DEFAULT entry to describe
the default assumptions.

While here, replace 0 by newly introduced constant.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-04-23 10:55:10 +02:00
Andy Shevchenko fed7026adc gpiolib: Make use of enum gpio_lookup_flags consistent
The library uses enum gpio_lookup_flags to define the possible
characteristics of GPIO pin. Since enumerator listed only individual
bits the common use of it is in a form of a bitmask of
gpio_lookup_flags GPIO_* values. The more correct type for this is
unsigned long.

Due to above convert all users to use unsigned long instead of
enum gpio_lookup_flags except enumerator definition.

While here, make field and parameter descriptions consistent as well.

Suggested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-04-23 10:55:07 +02:00
Andy Shevchenko 4050586b2b gpiolib: Indent entry values of enum gpio_lookup_flags
Indent entry values in the enum gpio_lookup_flags for better readability.

No functional change.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-04-23 10:54:42 +02:00
Linus Walleij 27157af663 gpio: mmio: Drop bgpio_dir_inverted
The direction inversion semantics are now handled by simply
using the registers for in/out available, no need to keep
track of inversion semantics exmplicitly anymore.

Reviewed-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Reviewed-by: Jan Kotas <jank@cadence.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-04-08 11:17:43 +02:00
Linus Walleij f69e00bd21 gpio: mmio: Support two direction registers
It turns out that one specific hardware has two direction
registers: one to set a GPIO line as input and another one
to set a GPIO line as output. So in theory a line can be
configured as input and output at the same time.

Make the MMIO GPIO helper deal with this: store both
registers in the state container, use both in the generic
code if present. Synchronize the input register to the
output register when we register a GPIO chip, with the
output settings taking precedence.

Keep the helper variable to detect inverted direction
semantics (only direction in register) but augment the
code to be more straight-forward for the generic case
when setting the registers.

Fix some flunky with unreadable direction registers at
the same time as we're touching this code.

Cc: David Woods <dwoods@mellanox.com>
Cc: Shravan Kumar Ramani <sramani@mellanox.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-04-05 00:04:13 +07:00
Jan Kundrát 64ebde5b0f gpiolib: export devprop_gpiochip_set_names()
This function is needed in mcp23s08. That driver is a special snowflake
because it supports several hardware chips as a single "GPIO chip" under
Linux.

Signed-off-by: Jan Kundrát <jan.kundrat@cesnet.cz>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Phil Reid <preid@electromag.com.au>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-03-24 04:48:02 +01:00
Linus Walleij 92de6bc3a8 Merge branch 'ib-pca953x-config' into devel 2019-02-14 08:45:22 +01:00
Thomas Petazzoni d449991c4d gpio: add core support for pull-up/pull-down configuration
This commit adds support for configuring the pull-up and pull-down
resistors available in some GPIO controllers. While configuring
pull-up/pull-down is already possible through the pinctrl subsystem,
some GPIO controllers, especially simple ones such as GPIO expanders
on I2C, don't have any pinmuxing capability and therefore do not use
the pinctrl subsystem.

This commit implements the GPIO_PULL_UP and GPIO_PULL_DOWN flags,
which can be used from the Device Tree, to enable a pull-up or
pull-down resistor on a given GPIO.

The flag is simply propagated all the way to the core GPIO subsystem,
where it is used to call the gpio_chip ->set_config callback with the
appropriate existing PIN_CONFIG_BIAS_* values.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-02-13 09:10:14 +01:00
Brian Masney ef74f70e5a gpio: add irq domain activate/deactivate functions
This adds the two new functions gpiochip_irq_domain_activate and
gpiochip_irq_domain_deactivate that can be used as the activate and
deactivate functions in the struct irq_domain_ops. This is for
situations where only gpiochip_{lock,unlock}_as_irq needs to be called.
SPMI and SSBI GPIO are two users that will initially use these
functions.

Signed-off-by: Brian Masney <masneyb@onstation.org>
Suggested-by: Stephen Boyd <sboyd@kernel.org>
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-01-24 15:33:04 +01:00
Linus Torvalds 24dc83635f This is the bulk of GPIO changes for the v4.21 kernel series:
Core changes:
 
 - Some core changes are already in outside of this pull
   request as they came through the regulator tree, most
   notably devm_gpiod_unhinge() that removes devres refcount
   management from a GPIO descriptor. This is needed in
   subsystems such as regulators where the regulator core
   need to take over the reference counting and lifecycle
   management for a GPIO descriptor.
 
 - We dropped devm_gpiochip_remove() and devm_gpio_chip_match()
   as nothing needs it. We can bring it back if need be.
 
 - Add a global TODO so people see where we are going. This
   helps setting the direction now that we are two GPIO
   maintainers.
 
 - Handle the MMC CD/WP properties in the device tree core.
   (The bulk of patches activating this code is already
   merged through the MMC/SD tree.)
 
 - Augment gpiochip_request_own_desc() to pass a flag so
   we as gpiochips can request lines as active low or open
   drain etc even from ourselves.
 
 New drivers:
 
 - New driver for Cadence GPIO blocks.
 
 - New driver for Atmel SAMA5D2 PIOBU GPIO lines.
 
 Driver improvements:
 
 - A major refactoring of the PCA953x driver - this driver has
   been around for ages, and is now modernized to reduce code
   duplication that has stacked up and is using regmap to read
   write and cache registers.
 
 - Intel drivers are now maintained in a separate tree and
   start with a round of cleanups and unifications.
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Merge tag 'gpio-v4.21-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO updates from Linus Walleij:
 "This is the bulk of GPIO changes for the v4.21 kernel series.

  Core changes:

   - Some core changes are already in outside of this pull request as
     they came through the regulator tree, most notably
     devm_gpiod_unhinge() that removes devres refcount management from a
     GPIO descriptor. This is needed in subsystems such as regulators
     where the regulator core need to take over the reference counting
     and lifecycle management for a GPIO descriptor.

   - We dropped devm_gpiochip_remove() and devm_gpio_chip_match() as
     nothing needs it. We can bring it back if need be.

   - Add a global TODO so people see where we are going. This helps
     setting the direction now that we are two GPIO maintainers.

   - Handle the MMC CD/WP properties in the device tree core. (The bulk
     of patches activating this code is already merged through the
     MMC/SD tree.)

   - Augment gpiochip_request_own_desc() to pass a flag so we as
     gpiochips can request lines as active low or open drain etc even
     from ourselves.

  New drivers:

   - New driver for Cadence GPIO blocks.

   - New driver for Atmel SAMA5D2 PIOBU GPIO lines.

  Driver improvements:

   - A major refactoring of the PCA953x driver - this driver has been
     around for ages, and is now modernized to reduce code duplication
     that has stacked up and is using regmap to read write and cache
     registers.

   - Intel drivers are now maintained in a separate tree and start with
     a round of cleanups and unifications"

* tag 'gpio-v4.21-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (99 commits)
  gpio: sama5d2-piobu: Depend on OF_GPIO
  gpio: Add Cadence GPIO driver
  dt-bindings: gpio: Add bindings for Cadence GPIO
  gpiolib-acpi: remove unused variable 'err', cleans up build warning
  gpio: mxs: read pin level directly instead of using .get
  gpio: aspeed: remove duplicated statement
  gpio: add driver for SAMA5D2 PIOBU pins
  dt-bindings: arm: atmel: describe SECUMOD usage as a GPIO controller
  gpio/mmc/of: Respect polarity in the device tree
  dt-bindings: gpio: rcar: Add r8a774c0 (RZ/G2E) support
  memory: omap-gpmc: Get the header of the enum
  ARM: omap1: Fix new user of gpiochip_request_own_desc()
  gpio: pca953x: Add regmap dependency for PCA953x driver
  gpio: raspberrypi-exp: decrease refcount on firmware dt node
  gpiolib: Fix return value of gpio_to_desc() stub if !GPIOLIB
  gpio: pca953x: Restore registers after suspend/resume cycle
  gpio: pca953x: Zap single use of pca953x_read_single()
  gpio: pca953x: Zap ad-hoc reg_output cache
  gpio: pca953x: Zap ad-hoc reg_direction cache
  gpio: pca953x: Perform basic regmap conversion
  ...
2018-12-28 20:00:21 -08:00
Krzysztof Kozlowski c5510b8daf gpiolib: Fix return value of gpio_to_desc() stub if !GPIOLIB
If CONFIG_GPOILIB is not set, the stub of gpio_to_desc() should return
the same type of error as regular version: NULL.  All the callers
compare the return value of gpio_to_desc() against NULL, so returned
ERR_PTR would be treated as non-error case leading to dereferencing of
error value.

Fixes: 79a9becda8 ("gpiolib: export descriptor-based GPIO interface")
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-12-14 16:06:24 +01:00
Linus Walleij 21abf10381 gpio: Pass a flag to gpiochip_request_own_desc()
Before things go out of hand, make it possible to pass
flags when requesting "own" descriptors from a gpio_chip.
This is necessary if the chip wants to request a GPIO with
active low semantics, for example.

Cc: Janusz Krzysztofik <jmkrzyszt@gmail.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Roger Quadros <rogerq@ti.com>
Reviewed-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-12-14 14:24:33 +01:00
Linus Walleij 891ddbc79a
gpio: Add devm_gpiod_unhinge()
This adds a function named devm_gpiod_unhinge() that removes
the resource management from a GPIO descriptor.

I am not sure if this is the best anglosaxon name for the
function, no other managed resources have an equivalent
currently, but I chose "unhinge" as the closest intuitive
thing I could imagine that fits Rusty Russell's API design
criterions "the obvious use is the correct one" and
"the name tells you how to use it".

The idea came out of a remark from Mark Brown that it should
be possible to handle over management of a resource from
devres to the regulator core, and indeed we can do that.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-12-11 01:04:23 +00:00
Linus Walleij fe6c473e3e
gpio: Export gpiod_get_from_of_node()
This function already exist inside gpiolib, we were just
reluctant to make it available to the kernel at large as
the devm_* seemed to be enough for anyone.

However we found out that regulators need to do their own
lifecycle/refcounting on GPIO descriptors and explicitly
call gpiod_put() when done with a descriptor, so export
this function so we can hand the refcounting over to the
regulator core for these descriptors after retrieveal.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-12-11 01:04:04 +00:00
Johan Hovold eee3919c5f gpio: drop broken to_gpio_irq_chip() helper
Drop the broken to_gpio_irq_chip() container_of() helper, which would
break the build for anyone who tries to use it.

Specifically, struct gpio_irq_chip only holds a pointer to a struct
irq_chip so using container_of() on an irq-chip pointer makes no sense.

Fixes: da80ff81a8 ("gpio: Move irqchip into struct gpio_irq_chip")
Cc: Thierry Reding <treding@nvidia.com>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-11-16 22:46:02 +01:00
Muchun Song 18534df419 gpiolib: Fix possible use after free on label
gpiod_request_commit() copies the pointer to the label passed as
an argument only to be used later. But there's a chance the caller
could immediately free the passed string(e.g., local variable).
This could trigger a use after free when we use gpio label(e.g.,
gpiochip_unlock_as_irq(), gpiochip_is_requested()).

To be on the safe side: duplicate the string with kstrdup_const()
so that if an unaware user passes an address to a stack-allocated
buffer, we won't get the arbitrary label.

Also fix gpiod_set_consumer_name().

Signed-off-by: Muchun Song <smuchun@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-11-05 08:54:42 +01:00
Uwe Kleine-König 48207d7595 gpio: drop devm_gpiochip_remove()
There is hardly any reason to call devm_gpiochip_remove() because the
driver core handles calling gpiochip_remove() automatically.

To make it harder to introduce new (and probably unneeded) callers, drop
the function.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-11-05 08:54:42 +01:00
Linus Torvalds 114b5f8f7e This is the bulk of GPIO changes for the v4.20 series:
Core changes:
 
 - A patch series from Hans Verkuil to make it possible to
   enable/disable IRQs on a GPIO line at runtime and drive GPIO
   lines as output without having to put/get them from scratch.
   The irqchip callbacks have been improved so that they can
   use only the fastpatch callbacks to enable/disable irqs
   like any normal irqchip, especially the gpiod_lock_as_irq()
   has been improved to be callable in fastpath context.
   A bunch of rework had to be done to achieve this but it is
   a big win since I never liked to restrict this to slowpath.
   The only call requireing slowpath was try_module_get() and
   this is kept at the .request_resources() slowpath callback.
   In the GPIO CEC driver this is a big win sine a single
   line is used for both outgoing and incoming traffic, and
   this needs to use IRQs for incoming traffic while actively
   driving the line for outgoing traffic.
 
 - Janusz Krzysztofik improved the GPIO array API to pass a
   "cookie" (struct gpio_array) and a bitmap for setting or
   getting multiple GPIO lines at once. This improvement
   orginated in a specific need to speed up an OMAP1 driver and
   has led to a much better API and real performance gains
   when the state of the array can be used to bypass a lot
   of checks and code when we want things to go really fast.
   The previous code would minimize the number of calls
   down to the driver callbacks assuming the CPU speed was
   orders of magnitude faster than the I/O latency, but this
   assumption was wrong on several platforms: what we needed
   to do was to profile and improve the speed on the hot
   path of the array functions and this change is now
   completed.
 
 - Clean out the painful and hard to grasp BNF experiments
   from the device tree bindings. Future approaches are looking
   into using JSON schema for this purpose. (Rob Herring
   is floating a patch series.)
 
 New drivers:
 
 - The RCAR driver now supports r8a774a1 (RZ/G2M).
 
 - Synopsys GPIO via CREGs driver.
 
 Major improvements:
 
 - Modernization of the EP93xx driver to use irqdomain and
   other contemporary concepts.
 
 - The ingenic driver has been merged into the Ingenic pin
   control driver and removed from the GPIO subsystem.
 
 - Debounce support in the ftgpio010 driver.
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Merge tag 'gpio-v4.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO updates from Linus Walleij:
 "This is the bulk of GPIO changes for the v4.20 series:

  Core changes:

   - A patch series from Hans Verkuil to make it possible to
     enable/disable IRQs on a GPIO line at runtime and drive GPIO lines
     as output without having to put/get them from scratch.

     The irqchip callbacks have been improved so that they can use only
     the fastpatch callbacks to enable/disable irqs like any normal
     irqchip, especially the gpiod_lock_as_irq() has been improved to be
     callable in fastpath context.

     A bunch of rework had to be done to achieve this but it is a big
     win since I never liked to restrict this to slowpath. The only call
     requireing slowpath was try_module_get() and this is kept at the
     .request_resources() slowpath callback. In the GPIO CEC driver this
     is a big win sine a single line is used for both outgoing and
     incoming traffic, and this needs to use IRQs for incoming traffic
     while actively driving the line for outgoing traffic.

   - Janusz Krzysztofik improved the GPIO array API to pass a "cookie"
     (struct gpio_array) and a bitmap for setting or getting multiple
     GPIO lines at once.

     This improvement orginated in a specific need to speed up an OMAP1
     driver and has led to a much better API and real performance gains
     when the state of the array can be used to bypass a lot of checks
     and code when we want things to go really fast.

     The previous code would minimize the number of calls down to the
     driver callbacks assuming the CPU speed was orders of magnitude
     faster than the I/O latency, but this assumption was wrong on
     several platforms: what we needed to do was to profile and improve
     the speed on the hot path of the array functions and this change is
     now completed.

   - Clean out the painful and hard to grasp BNF experiments from the
     device tree bindings. Future approaches are looking into using JSON
     schema for this purpose. (Rob Herring is floating a patch series.)

  New drivers:

   - The RCAR driver now supports r8a774a1 (RZ/G2M).

   - Synopsys GPIO via CREGs driver.

  Major improvements:

   - Modernization of the EP93xx driver to use irqdomain and other
     contemporary concepts.

   - The ingenic driver has been merged into the Ingenic pin control
     driver and removed from the GPIO subsystem.

   - Debounce support in the ftgpio010 driver"

* tag 'gpio-v4.20-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (116 commits)
  gpio: Clarify kerneldoc on gpiochip_set_chained_irqchip()
  gpio: Remove unused 'irqchip' argument to gpiochip_set_cascaded_irqchip()
  gpio: Drop parent irq assignment during cascade setup
  mmc: pwrseq_simple: Fix incorrect handling of GPIO bitmap
  gpio: fix SNPS_CREG kconfig dependency warning
  gpiolib: Initialize gdev field before is used
  gpio: fix kernel-doc after devres.c file rename
  gpio: fix doc string for devm_gpiochip_add_data() to not talk about irq_chip
  gpio: syscon: Fix possible NULL ptr usage
  gpiolib: Show correct direction from the beginning
  pinctrl: msm: Use init_valid_mask exported function
  gpiolib: Add init_valid_mask exported function
  GPIO: add single-register GPIO via CREG driver
  dt-bindings: Document the Synopsys GPIO via CREG bindings
  gpio: mockup: use device properties instead of platform_data
  gpio: Slightly more helpful debugfs
  gpio: omap: Remove set but not used variable 'dev'
  gpio: omap: drop omap_gpio_list
  Accept partial 'gpio-line-names' property.
  gpio: omap: get rid of the conditional PM runtime calls
  ...
2018-10-23 08:45:05 +01:00
Mark Brown 4fd1f509e8
Merge branch 'regulator-4.20' into regulator-next 2018-10-21 17:00:02 +01:00
Linus Walleij b0ce7b29bf
regulator/gpio: Allow nonexclusive GPIO access
This allows nonexclusive (simultaneous) access to a single
GPIO line for the fixed regulator enable line. This happens
when several regulators use the same GPIO for enabling and
disabling a regulator, and all need a handle on their GPIO
descriptor.

This solution with a special flag is not entirely elegant
and should ideally be replaced by something more careful as
this makes it possible for several consumers to
enable/disable the same GPIO line to the left and right
without any consistency. The current use inside the regulator
core should however be fine as it takes special care to
handle this.

For the state of the GPIO backend, this is still the
lesser evil compared to going back to global GPIO
numbers.

Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Jon Hunter <jonathanh@nvidia.com>
Fixes: efdfeb079c ("regulator: fixed: Convert to use GPIO descriptor only")
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>
2018-10-12 18:55:02 +02:00
Stephen Boyd 3e779a2e7f gpio: Assign gpio_irq_chip::parents to non-stack pointer
gpiochip_set_cascaded_irqchip() is passed 'parent_irq' as an argument
and then the address of that argument is assigned to the gpio chips
gpio_irq_chip 'parents' pointer shortly thereafter. This can't ever
work, because we've just assigned some stack address to a pointer that
we plan to dereference later in gpiochip_irq_map(). I ran into this
issue with the KASAN report below when gpiochip_irq_map() tried to setup
the parent irq with a total junk pointer for the 'parents' array.

BUG: KASAN: stack-out-of-bounds in gpiochip_irq_map+0x228/0x248
Read of size 4 at addr ffffffc0dde472e0 by task swapper/0/1

CPU: 7 PID: 1 Comm: swapper/0 Not tainted 4.14.72 #34
Call trace:
[<ffffff9008093638>] dump_backtrace+0x0/0x718
[<ffffff9008093da4>] show_stack+0x20/0x2c
[<ffffff90096b9224>] __dump_stack+0x20/0x28
[<ffffff90096b91c8>] dump_stack+0x80/0xbc
[<ffffff900845a350>] print_address_description+0x70/0x238
[<ffffff900845a8e4>] kasan_report+0x1cc/0x260
[<ffffff900845aa14>] __asan_report_load4_noabort+0x2c/0x38
[<ffffff900897e098>] gpiochip_irq_map+0x228/0x248
[<ffffff900820cc08>] irq_domain_associate+0x114/0x2ec
[<ffffff900820d13c>] irq_create_mapping+0x120/0x234
[<ffffff900820da78>] irq_create_fwspec_mapping+0x4c8/0x88c
[<ffffff900820e2d8>] irq_create_of_mapping+0x180/0x210
[<ffffff900917114c>] of_irq_get+0x138/0x198
[<ffffff9008dc70ac>] spi_drv_probe+0x94/0x178
[<ffffff9008ca5168>] driver_probe_device+0x51c/0x824
[<ffffff9008ca6538>] __device_attach_driver+0x148/0x20c
[<ffffff9008ca14cc>] bus_for_each_drv+0x120/0x188
[<ffffff9008ca570c>] __device_attach+0x19c/0x2dc
[<ffffff9008ca586c>] device_initial_probe+0x20/0x2c
[<ffffff9008ca18bc>] bus_probe_device+0x80/0x154
[<ffffff9008c9b9b4>] device_add+0x9b8/0xbdc
[<ffffff9008dc7640>] spi_add_device+0x1b8/0x380
[<ffffff9008dcbaf0>] spi_register_controller+0x111c/0x1378
[<ffffff9008dd6b10>] spi_geni_probe+0x4dc/0x6f8
[<ffffff9008cab058>] platform_drv_probe+0xdc/0x130
[<ffffff9008ca5168>] driver_probe_device+0x51c/0x824
[<ffffff9008ca59cc>] __driver_attach+0x100/0x194
[<ffffff9008ca0ea8>] bus_for_each_dev+0x104/0x16c
[<ffffff9008ca58c0>] driver_attach+0x48/0x54
[<ffffff9008ca1edc>] bus_add_driver+0x274/0x498
[<ffffff9008ca8448>] driver_register+0x1ac/0x230
[<ffffff9008caaf6c>] __platform_driver_register+0xcc/0xdc
[<ffffff9009c4b33c>] spi_geni_driver_init+0x1c/0x24
[<ffffff9008084cb8>] do_one_initcall+0x240/0x3dc
[<ffffff9009c017d0>] kernel_init_freeable+0x378/0x468
[<ffffff90096e8240>] kernel_init+0x14/0x110
[<ffffff9008086fcc>] ret_from_fork+0x10/0x18

The buggy address belongs to the page:
page:ffffffbf037791c0 count:0 mapcount:0 mapping:          (null) index:0x0
flags: 0x4000000000000000()
raw: 4000000000000000 0000000000000000 0000000000000000 00000000ffffffff
raw: ffffffbf037791e0 ffffffbf037791e0 0000000000000000 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffffffc0dde47180: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffffc0dde47200: f1 f1 f1 f1 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f2 f2
>ffffffc0dde47280: f2 f2 00 00 00 00 00 00 00 00 00 00 f3 f3 f3 f3
                                                       ^
 ffffffc0dde47300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffffc0dde47380: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

Let's leave around one unsigned int in the gpio_irq_chip struct for the
single parent irq case and repoint the 'parents' array at it. This way
code is left mostly intact to setup parents and we waste an extra few
bytes per structure of which there should be only a handful in a system.

Cc: Evan Green <evgreen@chromium.org>
Cc: Thierry Reding <treding@nvidia.com>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Fixes: e0d8972898 ("gpio: Implement tighter IRQ chip integration")
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-10-10 14:03:27 +02:00
Ricardo Ribalda Delgado f8ec92a9f6 gpiolib: Add init_valid_mask exported function
Add a function that allows initializing the valid_mask from
gpiochip_add_data.

This prevents race conditions during gpiochip initialization.

If the function is not exported, then the old behaviour is respected,
this is, set all gpios as valid.

Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Tested-by: Jeffrey Hugo <jhugo@codeaurora.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-10-10 10:31:40 +02:00
Geert Uytterhoeven 3c940660cb gpio: Restore indentation of continued lines
Fixes: 3027743f83 ("gpio: Remove VLA from gpiolib")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-10-01 12:22:41 +02:00
Geert Uytterhoeven cf9af0d578 gpio: Propagate errors from gpiod_set_array_value_complex()
Internal helper function gpiod_set_array_value_complex() was changed to
return an error value, but not all gpiolib callers were updated to
propagate the new error up.

Fixes: 3027743f83 ("gpio: Remove VLA from gpiolib")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-10-01 12:22:15 +02:00
Linus Walleij e48d194d12 gpio: Add comments on single direction chips
A patch from Ricardo got me thinking about some gpio chip
semantics so let's drop in some comments to make things
more clear around that.

Cc: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Cc: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-25 09:54:14 +02:00
Linus Walleij a2ab170374 Merge branch 'ib-array-bitmaps' into devel 2018-09-20 08:36:36 -07:00
Janusz Krzysztofik 77588c14ac gpiolib: Pass array info to get/set array functions
In order to make use of array info obtained from gpiod_get_array() and
speed up processing of arrays matching single GPIO chip layout, that
information must be passed to get/set array functions.  Extend the
functions' API with that additional parameter and update all users.
Pass NULL if a user builds an array itself from single GPIOs.

Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Miguel Ojeda Sandonis <miguel.ojeda.sandonis@gmail.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Sebastien Bourdelin <sebastien.bourdelin@savoirfairelinux.com>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Peter Korsgaard <peter.korsgaard@barco.com>
Cc: Peter Rosin <peda@axentia.se>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Rojhalat Ibrahim <imr@rtschenk.de>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Kishon Vijay Abraham I <kishon@ti.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Michael Hennerich <Michael.Hennerich@analog.com>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: Hartmut Knaack <knaack.h@gmx.de>
Cc: Peter Meerwald-Stadler <pmeerw@pmeerw.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Yegor Yefremov <yegorslists@googlemail.com>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-13 11:16:54 +02:00
Janusz Krzysztofik bf9346f5d4 gpiolib: Identify arrays matching GPIO hardware
Certain GPIO array lookup results may map directly to GPIO pins of a
single GPIO chip in hardware order.  If that condition is recognized
and handled efficiently, significant performance gain of get/set array
functions may be possible.

While processing a request for an array of GPIO descriptors, identify
those which represent corresponding pins of a single GPIO chip.  Skip
over pins which require open source or open drain special processing.
Moreover, identify pins which require inversion.  Pass a pointer to
that information with the array to the caller so it can benefit from
enhanced performance as soon as get/set array functions can accept and
make efficient use of it.

Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-13 11:16:12 +02:00
Janusz Krzysztofik b9762bebc6 gpiolib: Pass bitmaps, not integer arrays, to get/set array
Most users of get/set array functions iterate consecutive bits of data,
usually a single integer, while processing array of results obtained
from, or building an array of values to be passed to those functions.
Save time wasted on those iterations by changing the functions' API to
accept bitmaps.

All current users are updated as well.

More benefits from the change are expected as soon as planned support
for accepting/passing those bitmaps directly from/to respective GPIO
chip callbacks if applicable is implemented.

Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Miguel Ojeda Sandonis <miguel.ojeda.sandonis@gmail.com>
Cc: Sebastien Bourdelin <sebastien.bourdelin@savoirfairelinux.com>
Cc: Lukas Wunner <lukas@wunner.de>
Cc: Peter Korsgaard <peter.korsgaard@barco.com>
Cc: Peter Rosin <peda@axentia.se>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Rojhalat Ibrahim <imr@rtschenk.de>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Russell King <rmk+kernel@armlinux.org.uk>
Cc: Kishon Vijay Abraham I <kishon@ti.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Michael Hennerich <Michael.Hennerich@analog.com>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: Hartmut Knaack <knaack.h@gmx.de>
Cc: Peter Meerwald-Stadler <pmeerw@pmeerw.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Yegor Yefremov <yegorslists@googlemail.com>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-13 11:15:30 +02:00
Hans Verkuil 461c1a7d47 gpiolib: override irq_enable/disable
When using the gpiolib irqchip helpers install irq_enable/disable
hooks for the irqchip to ensure that gpiolib knows when the irq
is enabled or disabled, allowing drivers to disable the irq and then
use it as an output pin, and later switch the direction to input and
re-enable the irq.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-10 08:56:38 +02:00
Hans Verkuil 4e9439ddac gpiolib: add flag to indicate if the irq is disabled
GPIO drivers call gpiochip_(un)lock_as_irq whenever they want to use a gpio
as an interrupt. This is done when the irq is requested and it marks the
gpio as in use by an interrupt.

This is problematic for cases where a gpio pin is used as an interrupt
pin, then, after the irq is disabled, is used as a regular gpio pin.
Currently it is not possible to do this other than by first freeing
the interrupt so gpiochip_unlock_as_irq is called, since an attempt to
switch the gpio direction for output will fail since gpiolib believes
that the gpio is in use for an interrupt and it does not know that it
the irq is actually disabled.

There are currently two drivers that would like to be able to do this:
the tda998x_drv.c driver where a regular gpio pin needs to be temporarily
reconfigured as an interrupt pin during CEC calibration, and the cec-gpio
driver where you want to configure the gpio pin as an interrupt while
waiting for traffic over the CEC bus, or as a regular pin when receiving or
transmitting a CEC message.

The solution is to add a new flag that is set when the irq is enabled,
and have gpiod_direction_output check for that flag.

We also add functions that drivers that do not use GPIOLIB_IRQCHIP
can call when they enable/disable the irq.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-10 08:56:11 +02:00
Hans Verkuil 4e6b823867 gpiolib: export gpiochip_irq_reqres/relres()
GPIO drivers that do not use GPIOLIB_IRQCHIP can hook these into
the irq_request_resource and irq_release_resource callbacks of the
irq_chip so they correctly 'get' the module and lock the gpio line
for IRQ use.

This will simplify driver code.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-10 08:54:57 +02:00
Randy Dunlap 02ad0437de gpio: fix kernel-doc notation warning for 'request_key'
Fix kernel-doc warning for missing struct member 'request_key':

../include/linux/gpio/driver.h:142: warning: Function parameter or member 'request_key' not described in 'gpio_irq_chip'

Fixes: 39c3fd5895 ("kernel/irq: Extend lockdep class for request mutex")

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: linux-gpio@vger.kernel.org
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-10 08:48:24 +02:00
Linus Walleij d799a4de0a gpio: mmio: Fix up inverted direction registers
The bgpio_init() takes one of two arguments to specify a register
to set the direction of the GPIO line: either dirout that
indicates that a 1 in the bit in that register sets the
corresponding line to output, or dirin which indicates that
a 1 in the bit in that register sets the corresponding line to
input. Conversely setting the bit to 0 on these will turn the
line into input and output respectively. One of these can
be defined but not both.

This means that a platform that sets a bit to 1 for output
only defines dirout and a platform that sets a bit to 0 for
output only defines dirin. In short this defines the polarity
of the direction register.

Both can also be left as NULL meaning the GPIO chip is either
input only or output only.

Tomer Maimon discovered that for get/set chips (those where the
get and set registers are defined but no separate clear register,
and specifying BGPIOF_READ_OUTPUT_REG_SET so that we say we
want to read the output value from the SET register)
we are unconditionally reading the value from the SET register
when the direction bit is 1 and from the DAT register when the
direction bit is 0, not taking the direction bit polarity into
account.

It would be expected that when the direction bit is inverted
(dirin is defined but not dirout) we read the current value from
the DAT register when the bit is 1 and from the SET register
when the bit is 0.

Currently only some versions of ATH79, brcmstb, some versions of
CLP711x, GE, IOP and Loongson use the dirin mode (a 1 in the
register means input). They are unaffected because
BGPIOF_READ_OUTPUT_REG_SET is not set on any of them. (They
do not read back the SET register to figure out the output
value.) So this is no regression with current drivers.

However the behaviour is wrong and does not work with Tomer's
new driver where he needs to use the BGIOF_READ_OUTPUT_REG_SET.
This fixes the above issue by:

- Instead of defining separate functions for the inverted case,
  set up a flag in the gpio_chip that indicates that the
  direction is inverted.
- Remove the special inverted functions for setting
  input/output and getting the direction, rely on the flag
  instead.
- Respect this flag in bgpio_get_set() and
  bgpio_get_set_multiple()

Reported-by: Tomer Maimon <tmaimon77@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-08-10 23:19:17 +02:00
Andy Shevchenko 0969a204bf gpiolib: Use GPIOD_OUT_{LOW,HIGH} macros in open drain ones
There should not be anything more than stated by the name of newly
introduced constants, i.e.
	GPIOD_OUT_LOW_OPEN_DRAIN == GPIOD_OUT_LOW + open drain
and nothing more.

Make it better to read and slightly more robust by using GPIOD_OUT_LOW
and GPIOD_OUT_HIGH constants with open drain flag.

No functional change intended.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-30 00:06:33 +02:00
Linus Walleij 2b6c83cad1 Merge branch 'ib-aspeed' into devel 2018-07-02 16:10:25 +02:00
Benjamin Herrenschmidt a7ca13826e gpio: aspeed: Add interfaces for co-processor to grab GPIOs
On the Aspeed chip, the GPIOs can be under control of the ARM
chip or of the ColdFire coprocessor. (There's a third command
source, the LPC bus, which we don't use or support yet).

The control of which master is allowed to modify a given
GPIO is per-bank (8 GPIOs).

Unfortunately, systems already exist for which we want to
use GPIOs of both sources in the same bank.

This provides an API exported by the gpio-aspeed driver
that an aspeed coprocessor driver can use to "grab" some
GPIOs for use by the coprocessor, and allow the coprocessor
driver to provide callbacks for arbitrating access.

Once at least one GPIO of a given bank has been "grabbed"
by the coprocessor, the entire bank is marked as being
under coprocessor control. It's command source is switched
to the coprocessor.

If the ARM then tries to write to a GPIO in such a marked bank,
the provided callbacks are used to request access from the
coprocessor driver, which is responsible to doing whatever
is necessary to "pause" the coprocessor or prevent it from
trying to use the GPIOs while the ARM is doing its accesses.

During that time, the command source for the bank is temporarily
switched back to the ARM.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-07-02 16:10:15 +02:00
Linus Walleij 90b39402e9 gpio: Add API to explicitly name a consumer
The GPIO (descriptor) API registers a "label" naming what is
currently using the GPIO line. Typically this is taken from
things like the device tree node, so "reset-gpios" will result
in he line being labeled "reset".

The technical effect is pretty much zero: the use is for
debug and introspection, such as "lsgpio" and debugfs files.

However sometimes the user want this cuddly feeling of
listing all GPIO lines and seeing exactly what they are for
and it gives a very fulfilling sense of control. Especially
in the cases when the device tree node doesn't provide a
good name, or anonymous GPIO lines assigned just to
"gpios" in the device tree because the usage is implicit.

For these cases it may be nice to be able to label the
line directly and explicitly.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-06-18 07:55:30 +02:00
Laura Abbott 3027743f83 gpio: Remove VLA from gpiolib
The new challenge is to remove VLAs from the kernel
(see https://lkml.org/lkml/2018/3/7/621) to eventually
turn on -Wvla.

Using a kmalloc array is the easy way to fix this but kmalloc is still
more expensive than stack allocation. Introduce a fast path with a
fixed size stack array to cover most chip with gpios below some fixed
amount. The slow path dynamically allocates an array to cover those
chips with a large number of gpios.

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Phil Reid <preid@electromag.com.au>
Reviewed-and-tested-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Laura Abbott <labbott@redhat.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-05-23 14:01:03 +02:00
Bartosz Golaszewski a411e81e61 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>
2018-05-16 14:35:24 +02:00
Stephen Boyd 726cb3ba49 gpiolib: Support 'gpio-reserved-ranges' property
Some qcom platforms make some GPIOs or pins unavailable for use by
non-secure operating systems, and thus reading or writing the registers
for those pins will cause access control issues. Add support for a DT
property to describe the set of GPIOs that are available for use so that
higher level OSes are able to know what pins to avoid reading/writing.
Non-DT platforms can add support by directly updating the
chip->valid_mask.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Tested-by: Timur Tabi <timur@codeaurora.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-03-27 15:34:20 +02:00
Linus Torvalds 9798f5178f The is the bulk of GPIO changes for the v4.16 kernel cycle.
Core changes:
 
 - Disallow open drain and open source flags to be set
   simultaneously. This doesn't make electrical sense, and would
   the hardware actually respond to this setting, the result
   would be short circuit.
 
 - ACPI GPIO has a new core infrastructure for handling quirks.
   The quirks are there to deal with broken ACPI tables centrally
   instead of pushing the work to individual drivers. In the world
   of BIOS writers, the ACPI tables are perfect. Until they find a
   mistake in it. When such a mistake is found, we can patch it
   with a quirk. It should never happen, the problem is that it
   happens. So we accomodate for it.
 
 - Several documentation updates.
 
 - Revert the patch setting up initial direction state from
   reading the device. This was causing bad things for drivers
   that can't read status on all its pins. It is only affecting
   debugfs information quality.
 
 - Label descriptors with the device name if no explicit label is
   passed in.
 
 - Pave the ground for transitioning SPI and regulators to use
   GPIO descriptors by implementing some quirks in the device tree
   GPIO parsing code.
 
 New drivers:
 
 - New driver for the Access PCIe IDIO 24 family.
 
 Other:
 
 - Major refactorings and improvements to the GPIO mockup driver
   used for test and verification.
 
 - Moved the AXP209 driver over to pin control since it gained a
   pin control back-end. These patches will appear (with the same
   hashes) in the pin control pull request as well.
 
 - Convert the onewire GPIO driver w1-gpio to use descriptors.
   This is merged here since the W1 maintainers send very few
   pull requests and he ACKed it.
 
 - Start to clean up driver headers using <linux/gpio.h> to just
   use <linux/gpio/driver.h> as appropriate.
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Merge tag 'gpio-v4.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio

Pull GPIO updates from Linus Walleij:
 "The is the bulk of GPIO changes for the v4.16 kernel cycle. It is
  pretty calm this time around I think. I even got time to get to things
  like starting to clean up header includes.

  Core changes:

   - Disallow open drain and open source flags to be set simultaneously.
     This doesn't make electrical sense, and would the hardware actually
     respond to this setting, the result would be short circuit.

   - ACPI GPIO has a new core infrastructure for handling quirks. The
     quirks are there to deal with broken ACPI tables centrally instead
     of pushing the work to individual drivers. In the world of BIOS
     writers, the ACPI tables are perfect. Until they find a mistake in
     it. When such a mistake is found, we can patch it with a quirk. It
     should never happen, the problem is that it happens. So we
     accomodate for it.

   - Several documentation updates.

   - Revert the patch setting up initial direction state from reading
     the device. This was causing bad things for drivers that can't read
     status on all its pins. It is only affecting debugfs information
     quality.

   - Label descriptors with the device name if no explicit label is
     passed in.

   - Pave the ground for transitioning SPI and regulators to use GPIO
     descriptors by implementing some quirks in the device tree GPIO
     parsing code.

  New drivers:

   - New driver for the Access PCIe IDIO 24 family.

  Other:

   - Major refactorings and improvements to the GPIO mockup driver used
     for test and verification.

   - Moved the AXP209 driver over to pin control since it gained a pin
     control back-end. These patches will appear (with the same hashes)
     in the pin control pull request as well.

   - Convert the onewire GPIO driver w1-gpio to use descriptors. This is
     merged here since the W1 maintainers send very few pull requests
     and he ACKed it.

   - Start to clean up driver headers using <linux/gpio.h> to just use
     <linux/gpio/driver.h> as appropriate"

* tag 'gpio-v4.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (103 commits)
  gpio: Timestamp events in hardirq handler
  gpio: Fix kernel stack leak to userspace
  gpio: Fix a documentation spelling mistake
  gpio: Documentation update
  gpiolib: remove redundant initialization of pointer desc
  gpio: of: Fix NPE from OF flags
  gpio: stmpe: Delete an unnecessary variable initialisation in stmpe_gpio_probe()
  gpio: stmpe: Move an assignment in stmpe_gpio_probe()
  gpio: stmpe: Improve a size determination in stmpe_gpio_probe()
  gpio: stmpe: Use seq_putc() in stmpe_dbg_show()
  gpio: No NULL owner
  gpio: stmpe: i2c transfer are forbiden in atomic context
  gpio: davinci: Include proper header
  gpio: da905x: Include proper header
  gpio: cs5535: Include proper header
  gpio: crystalcove: Include proper header
  gpio: bt8xx: Include proper header
  gpio: bcm-kona: Include proper header
  gpio: arizona: Include proper header
  gpio: amd8111: Include proper header
  ...
2018-01-31 12:25:27 -08:00
Linus Walleij 92542edc42 gpio: Export devm_gpiod_get_from_of_node() for consumers
We have been holding back on adding an API for fetching GPIO handles
directly from device nodes, strongly preferring to get it from the
spawn devices instead.

The fwnode interface however already contains an API for doing this,
as it is used for opaque device tree nodes or ACPI nodes for getting
handles to LEDs and keys that use GPIO: those are specified as one
child per LED/key in the device tree and are not individual devices.

However regulators present a special problem as they already have
helper functions to traverse the device tree from a regulator node
and two levels down to fill in data, and as it already traverses
GPIO nodes in its own way, and already holds a pointer to each
regulators device tree node, it makes most sense to export an
API to fetch the GPIO descriptor directly from the node.

We only support the devm_* version for now, hopefully no non-devres
version will be needed.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-01-12 11:05:24 +01:00