The devm_ resource manager functions allow memory to be automatically
released when a device is unbound. This patch takes advantage of the
resource manager functions and replaces the gpiochip_add_data call and
request_irq call with the devm_gpiochip_add_data call and
devm_request_irq call respectively. In addition, the ws16c48_remove
function has been removed as no longer necessary due to the use of the
relevant devm_ resource manager functions.
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The devm_ resource manager functions allow memory to be automatically
released when a device is unbound. This patch takes advantage of the
resource manager functions and replaces the gpiochip_add_data call with
the devm_gpiochip_add_data call. In addition, the gpiomm_remove function
has been removed as no longer necessary due to the use of the relevant
devm_ resource manager functions.
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The devm_ resource manager functions allow memory to be automatically
released when a device is unbound. This patch takes advantage of the
resource manager functions and replaces the gpiochip_add_data call and
request_irq call with the devm_gpiochip_add_data call and
devm_request_irq call respectively. In addition, the idio_16_remove
function has been removed as no longer necessary due to the use of the
relevant devm_ resource manager functions.
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The devm_ resource manager functions allow memory to be automatically
released when a device is unbound. This patch takes advantage of the
resource manager functions and replaces the gpiochip_add_data call and
request_irq call with the devm_gpiochip_add_data call and
devm_request_irq call respectively. In addition, the idi_48_remove
function has been removed as no longer necessary due to the use of the
relevant devm_ resource manager functions.
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The devm_ resource manager functions allow memory to be automatically
released when a device is unbound. This patch takes advantage of the
resource manager functions and replaces the gpiochip_add_data call and
request_irq call with the devm_gpiochip_add_data call and
devm_request_irq call respectively. In addition, the dio48e_remove
function has been removed as no longer necessary due to the use of the
relevant devm_ resource manager functions.
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Currently we already have two pin configuration related callbacks
available for GPIO chips .set_single_ended() and .set_debounce(). In
future we expect to have even more, which does not scale well if we need
to add yet another callback to the GPIO chip structure for each possible
configuration parameter.
Better solution is to reuse what we already have available in the
generic pinconf.
To support this, we introduce a new .set_config() callback for GPIO
chips. The callback takes a single packed pin configuration value as
parameter. This can then be extended easily beyond what is currently
supported by just adding new types to the generic pinconf enum.
If the GPIO driver is backed up by a pinctrl driver the GPIO driver can
just assign gpiochip_generic_config() (introduced in this patch) to
.set_config and that will take care configuration requests are directed
to the pinctrl driver.
We then convert the existing drivers over .set_config() and finally
remove the .set_single_ended() and .set_debounce() callbacks.
Suggested-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This is less straight-forward than one would hope, as some banks only
have 4 pins rather than 8, others are output only, yet more (W and
X, already supported) are input-only, and in the case of the g4 SoC bank
AC doesn't exist.
Add some structs to describe the varying properties of different banks
and integrate mechanisms to deny requests for unsupported
configurations.
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The Aspeed SoCs have more GPIOs than can be represented with A-Z. The
documentation uses two letter names such as AA and AB, so make the names
a three-character array in the bank struct to accommodate this.
Signed-off-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Exar XR17V352/354/358 chips have 16 multi-purpose inputs/outputs which
can be controlled using gpio interface.
Add the gpio specific code.
Signed-off-by: Sudip Mukherjee <sudip.mukherjee@codethink.co.uk>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The WinSystems WS16C48 provides registers where 8 lines of GPIO may be
set at a time. This patch add support for the set_multiple callback
function, thus allowing multiple GPIO output lines to be set more
efficiently in groups.
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The Diamond Systems GPIO-MM series provides registers where 8 lines of
GPIO may be set at a time. This patch add support for the set_multiple
callback function, thus allowing multiple GPIO output lines to be set
more efficiently in groups.
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The ACCES 104-IDIO-16 series provides registers where 8 lines of GPIO
may be set at a time. This patch add support for the set_multiple
callback function, thus allowing multiple GPIO output lines to be set
more efficiently in groups.
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The ACCES 104-DIO-48E series provides registers where 8 lines of GPIO
may be set at a time. This patch add support for the set_multiple
callback function, thus allowing multiple GPIO output lines to be set
more efficiently in groups.
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This is a heavy edit/rewrite of the GPIO driver for the Gemini
SoC from arch/arm/mach-gemini/gpio.c.
This rewrite uses all the best-in-class helper like generic
GPIO and GPIOLIB_IRQCHIP and has been tested on ITian Square One
Gemini-based NAS/router.
Cc: Janos Laube <janos.dev@gmail.com>
Cc: Paulius Zaleckas <paulius.zaleckas@gmail.com>
Cc: Hans Ulli Kroll <ulli.kroll@googlemail.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
With the current redesign of driver it's not necessary to have
custom .xlate() as the gpiolib will assign default of_gpio_simple_xlate().
Suggested-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Keerthy <j-keerthy@ti.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Update GPIO driver to support Multiple GPIO controllers by updating
the base of subsequent GPIO chips with total of previous chips
gpio count so that gpio_add_chip gets unique numbers.
Signed-off-by: Keerthy <j-keerthy@ti.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The Davinci GPIO driver is implemented to work with one monolithic
Davinci GPIO platform device which may have up to Y(144) gpios.
The Davinci GPIO driver instantiates number of GPIO chips with
max 32 gpio pins per each during initialization and one IRQ domain.
So, the current GPIO's opjects structure is:
<platform device> Davinci GPIO controller
|- <gpio0_chip0> ------|
... |--- irq_domain (hwirq [0..143])
|- <gpio0_chipN> ------|
Current driver creates one chip for every 32 GPIOs in a controller.
This was a limitation earlier now there is no need for that. Hence
redesigning the driver to create one gpio chip for all the ngpio
in the controller.
|- <gpio0_chip0> ------|--- irq_domain (hwirq [0..143]).
The previous discussion on this can be found here:
https://www.spinics.net/lists/linux-omap/msg132869.html
Signed-off-by: Keerthy <j-keerthy@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
gpio2regs is written making an assumption that driver supports only
one instance of gpio controller. Removing this and adding a generic
array so as to support multiple instances of gpio controllers.
Signed-off-by: Keerthy <j-keerthy@ti.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The only usage of function intel_gpio_runtime_idle() is here (in the
same file):
static const struct dev_pm_ops intel_gpio_pm_ops = {
SET_RUNTIME_PM_OPS(NULL, NULL, intel_gpio_runtime_idle)
};
And when CONFIG_PM is not set, the macro SET_RUNTIME_PM_OPS expands to
nothing, causing the following compiler warning:
drivers/gpio/gpio-intel-mid.c:324:12: warning: ‘intel_gpio_runtime_idle’
defined but not used [-Wunused-function]
static int intel_gpio_runtime_idle(struct device *dev)
Fix it by annotating the function with __maybe_unused.
Signed-off-by: Augusto Mecking Caringi <augustocaringi@gmail.com>
Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Currently all users of fwnode_get_named_gpiod() have no way to
specify a label for the GPIO. So GPIOs listed in debugfs are shown
with label "?". With this change a proper label is used.
Also adjust all users so they can pass a label, properly retrieved
from device tree properties.
Signed-off-by: Alexander Stein <alexander.stein@systec-electronic.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Make fwnode_get_named_gpiod() consistent with the rest of
gpiod_get() like API, i.e. configure GPIO pin immediately after
request.
Besides obvious clean up it will help to configure pins based
on firmware provided resources.
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The helper function for adding a GPIO chip compiles in a lockdep
key for debugging, the same key is needed for nested chips as
well.
The macro construction is unreadable, replace this with two
static inlines instead.
The _gpiochip_irqchip_add prefixed function is not helpful,
rename it with gpiochip_irqchip_add_key() that tell us what the
function is actually doing.
Fixes: d245b3f9bd ("gpio: simplify adding threaded interrupts")
Cc: Roger Quadros <rogerq@ti.com>
Reported-by: Clemens Gruber <clemens.gruber@pqgruber.com>
Reported-by: Roger Quadros <rogerq@ti.com>
Reported-by: Grygorii Strashko <grygorii.strashko@ti.com>
Tested-by: Clemens Gruber <clemens.gruber@pqgruber.com>
Tested-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Casting a pointer to an int is not portable, and provokes a compiler
warning. Cast to unsigned long instead to avoid the warning.
drivers/gpio/gpio-mvebu.c: In function 'mvebu_gpio_probe':
drivers/gpio/gpio-mvebu.c:662:17: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
soc_variant = (int) match->data;
^
This will be needed when building gpio-mvebu for Armada 7k/8k ARM64
SoCs.
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Add optional reset-gpios pin control. If present, de-assert the
specified reset gpio pin to bring the chip out of reset.
v2:
- Specify that reset signal to PCA953x chip is active low, in
binding doc.
- reorder includes in gpio-pca953x.c.
- remove dev_err() on devm_gpiod_get_optional() error return.
Cc: Alexandre Courbot <gnurou@gmail.com>
Cc: linux-gpio@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Steve Longerbeam <steve_longerbeam@mentor.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
container_of() does pointer math on the pointer that's passed in.
If it were to return a NULL pointer the value passed in would
need to be perfectly offset from 0 to make that so. Remove these
checks because they don't make sense.
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
It seems the code had been changed, but description left untouched.
Update description of the struct acpi_gpio_info and relative comments
accordingly.
Fixes: commit 52044723cd ("ACPI / gpio: Add irq_type when a GPIO is used as an interrupt")
Cc: Christophe RICARD <christophe.ricard@gmail.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The macro for_each_set_bit() effectively looks up to the next
set bit in array of bits.
Instead of open coding that switch to for_each_set_bit() in
gpio_chip_set_multiple().
While here, make gpio_chip_set_multiple() non-destructive
against its parameters. We are safe since all callers, i.e.
gpiod_set_array_value_complex(), handle that already.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
davinci_gpio_controller struct has set_data, in_data, clr_data
members that are assigned and never used.
Signed-off-by: Keerthy <j-keerthy@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
We have already a global array of possible GPIO suffixes. Use it here instead
of another copy of them.
Unfortunately this will not reduce the memory footprint, though allows to easy
maintain list in only one place.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
When listing multiple GPIOs in the "gpios" property of a GPIO hog, only
the first GPIO is affected. The user is left clueless about the
dysfunctioning of the other GPIOs specified.
Fix this by adding and documenting support for specifying multiple
GPIOs in a single GPIO hog.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This patch updates my email address as I no longer have access to the old
one.
Signed-off-by: John Crispin <john@phrozen.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
When removing a gpiochip that uses GPIO hogging (e.g. by unloading the
chip's DT overlay), a warning is printed:
gpio gpiochip8: REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED
This happens because gpiochip_free_hogs() is called after the gdev->chip
pointer is reset to NULL. Hence __gpiod_free() cannot determine the
chip in use, and cannot clear flags nor call the optional chip-specific
.free() callback.
Move the call to gpiochip_free_hogs() up to fix this.
Cc: stable@vger.kernel.org
Fixes: ff2b135922 ("gpio: make the gpiochip a real device")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Building with an old toolchain, I ran into this warning:
WARNING: vmlinux.o(.text+0x63eef0): Section mismatch in reference
from the function mxs_gpio_probe() to the function
.init.text:mxs_gpio_init_gc()
Clearly the annotation is wrong, since the function is called from the
non-init probe, so let's remove it.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Currently the chip name buffer is allocated on the stack and the
address of the buffer is passed to the gpio framework. It's invalid
after probe() returns, so the sysfs label attribute displays garbage.
Use devm_kasprintf() for each string instead.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This variable is not used outside this module. Make it static.
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Currently gpio modules are runtime-resumed at probe time. This means the
gpio module will be active all the time (except during system suspend,
if not configured as a wake-up source).
While an R-Car Gen2 gpio module retains pins configured for output at
the requested level while put in standby mode, gpio register cannot be
accessed while suspended. Unfortunately pm_runtime_get_sync() cannot be
called from all contexts where gpio register access is needed. Hence
move the Runtime PM handling from probe/remove time to gpio request/free
time, which is probably the best we can do.
On r8a7791/koelsch, gpio modules 0, 1, 3, and 4 are now suspended during
normal use (gpio2 is used for LEDs and regulators, gpio5 for keys, gpio6
for SD-Card CD & WP, gpio7 for keys and regulators).
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
[Niklas: s/gpio_to_priv(chip)/gpiochip_get_data(chip)/]
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This enables Runtime PM handling for interrupts.
By setting the parent_device in struct irq_chip genirq will call the
pm_runtime_get/put APIs when an IRQ is requested/freed.
Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Core changes:
- Simplify threaded interrupt handling: instead of passing
numbed parameters to gpiochip_irqchip_add_chained() we
create a new call: gpiochip_irqchip_add_nested() so the two
types are clearly semantically different. Also make sure
that all nested chips call gpiochip_set_nested_irqchip()
which is necessary for IRQ resend to work properly if
it happens.
- Return error on seek operations for the chardev.
- Clamp values set as part of gpio[d]_direction_output() so
that anything != 0 will be send down to the driver as "1"
not the value passed in.
- ACPI can now support naming of GPIO lines, hogs and holes
in the GPIO lists.
New drivers:
- The SX150x driver was deemed unfit for the GPIO subsystem
and was moved over to a combined GPIO+pinctrl driver in the
pinctrl subsystem.
New features:
- Various cleanups to various drivers.
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Merge tag 'gpio-v4.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio
Pull GPIO updates from Luinus Walleij:
"Bulk GPIO changes for the v4.10 kernel cycle:
Core changes:
- Simplify threaded interrupt handling: instead of passing numbed
parameters to gpiochip_irqchip_add_chained() we create a new call:
gpiochip_irqchip_add_nested() so the two types are clearly
semantically different. Also make sure that all nested chips call
gpiochip_set_nested_irqchip() which is necessary for IRQ resend to
work properly if it happens.
- Return error on seek operations for the chardev.
- Clamp values set as part of gpio[d]_direction_output() so that
anything != 0 will be send down to the driver as "1" not the value
passed in.
- ACPI can now support naming of GPIO lines, hogs and holes in the
GPIO lists.
New drivers:
- The SX150x driver was deemed unfit for the GPIO subsystem and was
moved over to a combined GPIO+pinctrl driver in the pinctrl
subsystem.
New features:
- Various cleanups to various drivers"
* tag 'gpio-v4.10-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (49 commits)
gpio: merrifield: Implement gpio_get_direction callback
gpio: merrifield: Add support for hardware debouncer
gpio: chardev: Return error for seek operations
gpio: arizona: Tidy up probe error path
gpio: arizona: Remove pointless set of platform drvdata
gpio: pl061: delete platform data handling
gpio: pl061: move platform data into driver
gpio: pl061: rename variable from chip to pl061
gpio: pl061: rename state container struct
gpio: pl061: use local state for parent IRQ storage
gpio: set explicit nesting on drivers
gpio: simplify adding threaded interrupts
gpio: vf610: use builtin_platform_driver
gpio: axp209: use correct register for GPIO input status
gpio: stmpe: fix interrupt handling bug
gpio: em: depnd on ARCH_SHMOBILE
gpio: zx: depend on ARCH_ZX
gpio: x86: update config dependencies for x86 specific hardware
gpio: mb86s7x: use builtin_platform_driver
gpio: etraxfs: use builtin_platform_driver
...
By default all pins are configured to use a glitch filter. Writing 1 to the
certain bit of the specific register might be useful in case someone needs to
bypass the glitch filter completely for a given GPIO pin.
This patch adds support for that in the Intel Merrifield GPIO driver.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The GPIO chardev is used for management tasks (allocating line and event
handles) and does neither support read() nor write() operations. Hence it
does not make much sense to allow seek operations.
Currently the chardev uses noop_llseek() for its seek implementation. This
function does not move the pointer and simply returns the current position
(always 0 for the GPIO chardev). noop_llseek() is primarily meant for
devices that can not support seek, but where there might be a user that
depends on the seek() operation succeeding. For newly added devices that
can not support seek operations it is recommended to use no_llseek(), which
will return an error. For more information see commit 6038f373a3
("llseek: automatically add .llseek fop").
Unfortunately this was overlooked when the GPIO chardev ABI was introduced.
But it is highly unlikely that since then userspace applications have
appeared that rely on being able to perform non-failing seek operations on
a GPIO chardev file descriptor. So it should be safe to change from
noop_llseel() to no_seek(). Also use nonseekable_open() in the chardev
open() callback to clear the FMODE_SEEK, FMODE_PREAD and FMODE_PWRITE flags
from the file. Neither of these should be set on a file that does not
support seek operations.
Cc: stable@vger.kernel.org
Fixes: 3c702e9987 ("gpio: add a userspace chardev ABI for GPIOs")
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
There is some unnecessary complexity in the error path which now things
are converted to devm is actually very simple. This patch simplifies
things.
Signed-off-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
