Commit Graph

488 Commits

Author SHA1 Message Date
Andrew Jeffery fa59dd234c Revert "gpio: use new gpio_set_config() helper in more places"
gpio-aspeed implements support for PIN_CONFIG_INPUT_DEBOUNCE. As of
v5.1-rc1 we're seeing the following when booting a Romulus BMC kernel:

> [   21.373137] ------------[ cut here ]------------
> [   21.374545] WARNING: CPU: 0 PID: 1 at drivers/gpio/gpio-aspeed.c:834 unregister_allocated_timer+0x38/0x94
> [   21.376181] No timer allocated to offset 74
> [   21.377672] CPU: 0 PID: 1 Comm: swapper Not tainted 5.1.0-rc1-dirty #6
> [   21.378800] Hardware name: Generic DT based system
> [   21.379965] Backtrace:
> [   21.381024] [<80107d44>] (dump_backtrace) from [<80107f78>] (show_stack+0x20/0x24)
> [   21.382713]  r7:8038b720 r6:00000009 r5:00000000 r4:87897c64
> [   21.383815] [<80107f58>] (show_stack) from [<80656398>] (dump_stack+0x20/0x28)
> [   21.385042] [<80656378>] (dump_stack) from [<80115f1c>] (__warn.part.3+0xb4/0xdc)
> [   21.386253] [<80115e68>] (__warn.part.3) from [<80115fb0>] (warn_slowpath_fmt+0x6c/0x90)
> [   21.387471]  r6:00000342 r5:807f8758 r4:80a07008
> [   21.388278] [<80115f48>] (warn_slowpath_fmt) from [<8038b720>] (unregister_allocated_timer+0x38/0x94)
> [   21.389809]  r3:0000004a r2:807f8774
> [   21.390526]  r7:00000000 r6:0000000a r5:60000153 r4:0000004a
> [   21.391601] [<8038b6e8>] (unregister_allocated_timer) from [<8038baac>] (aspeed_gpio_set_config+0x330/0x48c)
> [   21.393248] [<8038b77c>] (aspeed_gpio_set_config) from [<803840b0>] (gpiod_set_debounce+0xe8/0x114)
> [   21.394745]  r10:82ee2248 r9:00000000 r8:87b63a00 r7:00001388 r6:87947320 r5:80729310
> [   21.396030]  r4:879f64a0
> [   21.396499] [<80383fc8>] (gpiod_set_debounce) from [<804b4350>] (gpio_keys_probe+0x69c/0x8e0)
> [   21.397715]  r7:845d94b8 r6:00000001 r5:00000000 r4:87b63a1c
> [   21.398618] [<804b3cb4>] (gpio_keys_probe) from [<8040eeec>] (platform_dev_probe+0x44/0x80)
> [   21.399834]  r10:00000003 r9:80a3a8b0 r8:00000000 r7:00000000 r6:80a7f9dc r5:80a3a8b0
> [   21.401163]  r4:8796bc10
> [   21.401634] [<8040eea8>] (platform_drv_probe) from [<8040d0d4>] (really_probe+0x208/0x3dc)
> [   21.402786]  r5:80a7f8d0 r4:8796bc10
> [   21.403547] [<8040cecc>] (really_probe) from [<8040d7a4>] (driver_probe_device+0x130/0x170)
> [   21.404744]  r10:0000007b r9:8093683c r8:00000000 r7:80a07008 r6:80a3a8b0 r5:8796bc10
> [   21.405854]  r4:80a3a8b0
> [   21.406324] [<8040d674>] (driver_probe_device) from [<8040da8c>] (device_driver_attach+0x68/0x70)
> [   21.407568]  r9:8093683c r8:00000000 r7:80a07008 r6:80a3a8b0 r5:00000000 r4:8796bc10
> [   21.408877] [<8040da24>] (device_driver_attach) from [<8040db14>] (__driver_attach+0x80/0x150)
> [   21.410327]  r7:80a07008 r6:8796bc10 r5:00000001 r4:80a3a8b0
> [   21.411294] [<8040da94>] (__driver_attach) from [<8040b20c>] (bus_for_each_dev+0x80/0xc4)
> [   21.412641]  r7:80a07008 r6:8040da94 r5:80a3a8b0 r4:87966f30
> [   21.413580] [<8040b18c>] (bus_for_each_dev) from [<8040dc0c>] (driver_attach+0x28/0x30)
> [   21.414943]  r7:00000000 r6:87b411e0 r5:80a33fc8 r4:80a3a8b0
> [   21.415927] [<8040dbe4>] (driver_attach) from [<8040bbf0>] (bus_add_driver+0x14c/0x200)
> [   21.417289] [<8040baa4>] (bus_add_driver) from [<8040e2b4>] (driver_register+0x84/0x118)
> [   21.418652]  r7:80a60ae0 r6:809226b8 r5:80a07008 r4:80a3a8b0
> [   21.419652] [<8040e230>] (driver_register) from [<8040fc28>] (__platform_driver_register+0x3c/0x50)
> [   21.421193]  r5:80a07008 r4:809525f8
> [   21.421990] [<8040fbec>] (__platform_driver_register) from [<809226d8>] (gpio_keys_init+0x20/0x28)
> [   21.423447] [<809226b8>] (gpio_keys_init) from [<8090128c>] (do_one_initcall+0x80/0x180)
> [   21.424886] [<8090120c>] (do_one_initcall) from [<80901538>] (kernel_init_freeable+0x1ac/0x26c)
> [   21.426354]  r8:80a60ae0 r7:80a60ae0 r6:8093685c r5:00000008 r4:809525f8
> [   21.427579] [<8090138c>] (kernel_init_freeable) from [<8066d9a0>] (kernel_init+0x18/0x11c)
> [   21.428819]  r10:00000000 r9:00000000 r8:00000000 r7:00000000 r6:00000000 r5:8066d988
> [   21.429947]  r4:00000000
> [   21.430415] [<8066d988>] (kernel_init) from [<801010e8>] (ret_from_fork+0x14/0x2c)
> [   21.431666] Exception stack(0x87897fb0 to 0x87897ff8)
> [   21.432877] 7fa0:                                     00000000 00000000 00000000 00000000
> [   21.434446] 7fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> [   21.436052] 7fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> [   21.437308]  r5:8066d988 r4:00000000
> [   21.438102] ---[ end trace d7d7ac3a80567d0e ]---

We only hit unregister_allocated_timer() if the argument to
aspeed_gpio_set_config() is 0, but we can't be calling through
gpiod_set_debounce() from gpio_keys_probe() unless the gpio-keys button has a
non-zero debounce interval.

Commit 6581eaf0e8 ("gpio: use new gpio_set_config() helper in more places")
spreads the use of gpio_set_config() to the debounce and transitory
state configuration paths. The implementation of gpio_set_config() is:

> static int gpio_set_config(struct gpio_chip *gc, unsigned offset,
> 			   enum pin_config_param mode)
> {
> 	unsigned long config = { PIN_CONF_PACKED(mode, 0) };
>
> 	return gc->set_config ? gc->set_config(gc, offset, config) : -ENOTSUPP;
> }

Here it packs its own config value with a fixed argument of 0; this is
incorrect behaviour for implementing the debounce and transitory functions, and
the debounce and transitory gpio_set_config() call-sites now have an undetected
type mismatch as they both already pack their own config parameter (i.e. what
gets passed is not an `enum pin_config_param`). Indeed this can be seen in the
small diff for 6581eaf0e890:

> diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
> index de595fa31a1a..1f239aac43df 100644
> --- a/drivers/gpio/gpiolib.c
> +++ b/drivers/gpio/gpiolib.c
> @@ -2725,7 +2725,7 @@ int gpiod_set_debounce(struct gpio_desc *desc, unsigned debounce)
>         }
>
>         config = pinconf_to_config_packed(PIN_CONFIG_INPUT_DEBOUNCE, debounce);
> -       return chip->set_config(chip, gpio_chip_hwgpio(desc), config);
> +       return gpio_set_config(chip, gpio_chip_hwgpio(desc), config);
>  }
>  EXPORT_SYMBOL_GPL(gpiod_set_debounce);
>
> @@ -2762,7 +2762,7 @@ int gpiod_set_transitory(struct gpio_desc *desc, bool transitory)
>         packed = pinconf_to_config_packed(PIN_CONFIG_PERSIST_STATE,
>                                           !transitory);
>         gpio = gpio_chip_hwgpio(desc);
> -       rc = chip->set_config(chip, gpio, packed);
> +       rc = gpio_set_config(chip, gpio, packed);
>         if (rc == -ENOTSUPP) {
>                 dev_dbg(&desc->gdev->dev, "Persistence not supported for GPIO %d\n",
>                                 gpio);

Revert commit 6581eaf0e8 ("gpio: use new gpio_set_config() helper in
more places") to restore correct behaviour for gpiod_set_debounce() and
gpiod_set_transitory().

Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2019-03-27 09:40:07 +01:00
Linus Walleij 8fab3d713c gpio updates for v5.1
- support for a new variant of pca953x
 - documentation fix from Wolfram
 - some tegra186 name changes
 - two minor fixes for madera and altera-a10sr
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Merge tag 'gpio-v5.1-updates-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/brgl/linux into devel

gpio updates for v5.1

- support for a new variant of pca953x
- documentation fix from Wolfram
- some tegra186 name changes
- two minor fixes for madera and altera-a10sr
2019-02-17 21:59:33 +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
Thomas Petazzoni 6581eaf0e8 gpio: use new gpio_set_config() helper in more places
As suggested by Linus Walleij, let's use the new gpio_set_config()
helper in gpiod_set_debounce() and gpiod_set_transitory().

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-02-13 09:09:06 +01:00
Thomas Petazzoni 7147978985 gpio: rename gpio_set_drive_single_ended() to gpio_set_config()
This commit simply renames gpio_set_drive_single_ended() to
gpio_set_config(), as the function is not specific to setting the GPIO
drive type, and will be used for other purposes in followup commits.

In addition, it moves the function above gpiod_direction_input(), as
it will be used from gpiod_direction_input().

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-02-13 09:08:35 +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
Bartosz Golaszewski 1033be5899 gpiolib: fix line event timestamps for nested irqs
Nested interrupts run inside the calling thread's context and the top
half handler is never called which means that we never read the
timestamp.

This issue came up when trying to read line events from a gpiochip
using regmap_irq_chip for interrupts.

Fix it by reading the timestamp from the irq thread function if it's
still 0 by the time the second handler is called.

Fixes: d58f2bf261 ("gpio: Timestamp events in hardirq handler")
Cc: stable@vger.kernel.org
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
2019-01-23 17:24:01 +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
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
Mark Brown e6202e8249
Merge branch 'for-linus' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/regulator into regulator-4.21 2018-12-11 20:44:49 +00:00
Linus Walleij ec757001c8
gpio: Enable nonexclusive gpiods from DT nodes
This makes gpiod_get_from_of_node() respect the
GPIOD_FLAGS_BIT_NONEXCLUSIVE flag which is especially
nice when getting regulator GPIOs right out of device
tree nodes.

Suggested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Fixes: b0ce7b29bf ("regulator/gpio: Allow nonexclusive GPIO access")
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 01:04:12 +00:00
Laurent Pinchart 0696d79456 gpio: drop devm_gpio_chip_match()
Commit 48207d7595 ("gpio: drop devm_gpiochip_remove()") dropped the
last user of drop devm_gpio_chip_match(), causing a defined but not used
compilation warning. Fix it by removing the function.

Fixes: 48207d7595 ("gpio: drop devm_gpiochip_remove()")
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-11-15 09:58:15 +01:00
Vladimir Zapolskiy a05a140499 gpio: don't free unallocated ida on gpiochip_add_data_with_key() error path
The change corrects the error path in gpiochip_add_data_with_key()
by avoiding to call ida_simple_remove(), if ida_simple_get() returns
an error.

Note that ida_simple_remove()/ida_free() throws a BUG(), if id argument
is negative, it allows to easily check the correctness of the fix by
fuzzing the return value from ida_simple_get().

Fixes: ff2b135922 ("gpio: make the gpiochip a real device")
Cc: stable@vger.kernel.org # v4.6+
Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-11-09 11:16:57 +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.
 -----BEGIN PGP SIGNATURE-----
 
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 mFT/t/IbTmRpCgbEv4CDx4Kc/InE0sUnQr1TL/1WvU6uObM6Ncxq5Z90MvyrgzYu
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 2jj1cdZztjv8A+9cspHDpQP+jDvl1VSc10nR5fRu1TttSpUwzRJaB30NBNXJmMJc
 5KUr67lEbsQRPsBvFErU11bydPqhfT+pXmODcfIwS0EtATQ8WC5mkSb/Ooei0fvT
 oZ7uR3Os8tMf7isOKssEyFabKwhnfOEt6TBt9em0TfUtInOo0Dc7r8TfBcn57fyZ
 xg2R9DQEVRfac8bjhF/BI5KHuN9IMGDDvj6XApumQVliZbISRjMnh3jte6RpcV0A
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 hujsxcJzGQqjCe0moeY/1d7vsy0ZjbHoS+p5fy79U212y2O7onEzFU92AX89bxKC
 rx2eCNmiZxCUy1nqu8edO62VnH6QdnqG3o+a4DJfCSHPvFM/E/NX9zHemZubQQ4I
 rYXNy4bL4tEG9cqWMfBxWrpiDZw7H6l8kXwdZG8IMyRU9BcKu96amgZ+jBXwzoaB
 JZelAAUWB9APghJYFr7o
 =YosT
 -----END PGP SIGNATURE-----

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
Stephen Boyd 40f5ff4f9f gpio: Clarify kerneldoc on gpiochip_set_chained_irqchip()
This doesn't support nested anymore, so drivers shouldn't call it with
the handler set to NULL.

Cc: Evan Green <evgreen@chromium.org>
Cc: Thierry Reding <treding@nvidia.com>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-10-16 09:30:22 +02:00
Stephen Boyd 3c1f6b2d11 gpio: Remove unused 'irqchip' argument to gpiochip_set_cascaded_irqchip()
This argument hasn't ever been used since it was introduced in commit
1425052097 ("gpio: add IRQ chip helpers in gpiolib"). Let's drop it to
reduce reading confusion.

Cc: Evan Green <evgreen@chromium.org>
Cc: Thierry Reding <treding@nvidia.com>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-10-16 09:29:30 +02:00
Stephen Boyd 9cb7cf9c4e gpio: Drop parent irq assignment during cascade setup
We want to set the irq parent for interrupts that we're setting up to be
cascaded from another interrupt controller, but we may or may not have
already mapped the gpiochip irqs into the kernel's virtual irq number
space at this point. If we have mapped irqs before calling here, then
we've gone through gpiochip_irq_map() and called irq_set_parent()
already. If we haven't mapped irqs, then the gpiochip is dynamically
mapping irqs and we can rely on gpiochip_irq_map() or the gpio driver's
irqdomain ops to setup the irq parent properly.

Either way, setting the parent here when cascading the gpiochip doesn't
make much sense because it should be done at irq mapping time. In the
dynamic mapping case, this code is mapping virq 0 to some parent virq in
a loop. While that's benign, let's drop this code to simplify.

Cc: Evan Green <evgreen@chromium.org>
Cc: Thierry Reding <treding@nvidia.com>
Cc: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-10-16 09:27:11 +02:00
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
Ricardo Ribalda Delgado 767cd17a5c gpiolib: Initialize gdev field before is used
gpio_hog depends on gdev field being initialized. This patch fixes an
OOPs during initialization of TI's AM335x-ICEv2.

Fixes: 3edfb7bd76 ("gpiolib: Show correct direction from the beginning")
Tested-by: Vignesh R <vigneshr@ti.com>
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-10-12 10:16:19 +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
Uwe Kleine-König 3925b90fa4 gpio: fix doc string for devm_gpiochip_add_data() to not talk about irq_chip
The function is about adding a gpio_chip so dev has to belong to this
one. Fix wording to be more grammatically correct (but attention, I'm
not a native speaker).

Signed-off-by: Uwe Kleine-König <uwe@kleine-koenig.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-10-10 13:36:18 +02:00
Ricardo Ribalda Delgado 3edfb7bd76 gpiolib: Show correct direction from the beginning
Current code assumes that the direction is input if direction_input
function is set.
This might not be the case on GPIOs with programmable direction.

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 10:32:00 +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
Linus Walleij 90fd227029 gpio: Slightly more helpful debugfs
This at least makes debugfs print if the line is active
high or low. That is pretty helpful as what we display
as "lo" or "hi" is the raw physical level of the line.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-10-02 10:06:29 +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
Janusz Krzysztofik 799d5eb4e7 gpiolib: Fix incorrect use of find_next_zero_bit()
Commit b17566a6b0 ("gpiolib: Implement fast processing path in
get/set array"), already fixed to some extent with commit 5d581d7e8cdc
("gpiolib: Fix missing updates of bitmap index"), introduced a new mode
of processing bitmaps where bits applicable for fast bitmap processing
path are supposed to be skipped while iterating bits which don't apply.
Unfortunately, find_next_zero_bit() function supposed to skip over
those fast bits is always called with a 'start' argument equal to an
index of last zero bit found and returns that index value again an
again, causing an infinite loop.

Fix it by incrementing the index uncoditionally before
find_next_zero_bit() is optionally called.

Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-10-01 11:35:37 +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
Ricardo Ribalda Delgado ae9847f48a gpiolib: Fix gpio_direction_* for single direction GPIOs
GPIOs with no programmable direction are not required to implement
direction_output nor direction_input.

If we try to set an output direction on an output-only GPIO or input
direction on an input-only GPIO simply return 0.

This allows this single direction GPIO to be used by libgpiod.

Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-25 09:34:48 +02:00
Linus Walleij dae5f0afcf gpio: Use SPDX header for core library
Use the SPDX headers and cut down on boilerplate to indicate the
license in the core gpiolib implementation.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-25 09:08:48 +02:00
Janusz Krzysztofik c4c958aa64 gpiolib: Fix array members of same chip processed separately
New code introduced by commit bf9346f5d4 ("gpiolib: Identify arrays
matching GPIO hardware") forcibly tries to find an array member which
has its array index number equal to its hardware pin number and set
up an array info for possible fast bitmap processing of all arrray
pins belonging to that chip which also satisfy that numbering rule.

Depending on array content, it may happen that consecutive array
members which belong to the same chip but don't have array indexes
equal to their pin hardware numbers will be split into groups, some of
them processed together via the fast bitmap path, and rest of them
separetely.  However, applications may expect all those pins being
processed together with a single call to .set_multiple() chip callback,
like that was done before the change.

Limit applicability of fast bitmap processing path to cases where all
pins of consecutive array members starting from 0 which belong to the
same chip have their hardware numbers equal to their corresponding
array indexes.  That should still speed up processing of applications
using whole GPIO banks as I/O ports, while not breaking simultaneous
manipulation of consecutive pins of the same chip which don't follow
the equal numbering rule.

Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-24 13:47:05 +02:00
Janusz Krzysztofik 35ae7f9694 gpiolib: Fix missing updates of bitmap index
In new code introduced by commit b17566a6b0 ("gpiolib: Implement fast
processing path in get/set array"), bitmap index is not updated with
next found zero bit position as it should while skipping over pins
already processed via fast bitmap path, possibly resulting in an
infinite loop.  Fix it.

Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-24 13:46:53 +02:00
Linus Walleij a2ab170374 Merge branch 'ib-array-bitmaps' into devel 2018-09-20 08:36:36 -07:00
Ricardo Ribalda Delgado 19a4fbffc9 gpiolib: Free the last requested descriptor
The current code only frees N-1 gpios if an error occurs during
gpiod_set_transitory, gpiod_direction_output or gpiod_direction_input.
Leading to gpios that cannot be used by userspace nor other drivers.

Cc: Timur Tabi <timur@codeaurora.org>
Cc: stable@vger.kernel.org
Fixes: ab3dbcf78f ("gpioib: do not free unrequested descriptors)
Reported-by: Jan Lorenzen <jl@newtec.dk>
Reported-by: Jim Paris <jim@jtan.com>
Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-18 16:36:05 -07:00
Hans Verkuil 171948ea33 gpiolib: check if irqchip already has the irq hook replacements
Some drivers use a single irqchip for multiple gpiochips. As a result the
irqchip hooks are overridden for the first gpiochip that was added, but
for the other gpiochip instances this should not happen again, otherwise
we would go into an infinite recursion.

Check for this, but also log a message that the driver should be fixed
since this is bad practice.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Tested-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-17 08:24:02 -07:00
Wolfram Sang d0121b8548 gpiolib: use better errno if get_direction is not available
EINVAL is very generic, use ENOTSUPP in case the gpiochip does not
provide this function. While removing the assignment from the 'status'
variable, use better indentation in the declaration block.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-14 10:45:13 +02:00
Janusz Krzysztofik b17566a6b0 gpiolib: Implement fast processing path in get/set array
Certain GPIO descriptor arrays returned by gpio_get_array() may contain
information on direct mapping of array members to pins of a single GPIO
chip in hardware order.  In such cases, bitmaps of values can be passed
directly from/to the chip's .get/set_multiple() callbacks without
wasting time on iterations.

Add respective code to gpiod_get/set_array_bitmap_complex() functions.
Pins not applicable for fast path are processed as before, skipping
over the 'fast' ones.

Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Janusz Krzysztofik <jmkrzyszt@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-13 11:17:23 +02:00
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
Uwe Kleine-König fa38869b01 gpiolib: Don't support irq sharing for userspace
This concerns gpio edge detection for GPIO IRQs used from
userspace for GPIO event listeners.

Trying to work out the right event if it's not sure that the
examined gpio actually moved is impossible.

Consider two gpios "gpioA" and "gpioB" that share an interrupt.
gpioA's irq should trigger on any edge, gpioB's on a falling edge.
If now the common irq fires and both gpio lines are high, there
are several possibilities that could have happend:

 a) gpioA just had a low-to-high edge
 b) gpioB just had a high-to-low-to-high spike
 c) a combination of both a) and b)

While c) is unlikely (in most setups) a) and b) alone are bad
enough. Currently the code assumes case a) unconditionally and
doesn't report an event for gpioB. Note that even if there is no
irq sharing involved a spike for a gpio might not result in an
event if it's configured to trigger for a single edge only.

The only way to improve this is to drop support for interrupt
sharing. This way a spike results in an event for the right gpio
at least. Note that apart from dropping IRQF_SHARED this
effectively undoes commit df1e76f28f
("gpiolib: skip unwanted events, don't convert them to opposite edge").

This obviously breaks setups that rely on interrupt sharing,
but given that this cannot be reliable, this is probably an
acceptable trade-off.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
[Assuming there are no users of interrupt sharing yet]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-13 10:58:38 +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 ca620f2de1 gliolib: set hooks in gpiochip_set_irq_hooks()
Centralize setting the irq_request/release_resources callbacks
in one function since we'll be adding more callbacks to that.

Also fix the removal of the callback overrides: this should
only be done if we actually installed our own callback there.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-09-10 08:55:38 +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
Biju Das 3789f5acb9 gpiolib: Avoid calling chip->request() for unused gpios
Add a check for unused gpios to avoid chip->request() call to client
driver for unused gpios.

Signed-off-by: Biju Das <biju.das@bp.renesas.com>
Reviewed-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2018-08-10 23:19:17 +02:00