Fix race condition when changing the direction (in/out) of the GPIO pin.
The read-modify-write sequence (as coded in the driver) isn't atomic and
requires synchronization (spinlock).
Signed-off-by: Glenn Langedock <Glenn.Langedock@barco.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Srinivas Neeli <srinivas.neeli@xilinx.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
This patch writes the inverse value of Interrupt Mask Status
register into the Interrupt Enable register in
zynq_gpio_restore_context API to fix the bug.
Fixes: e11de4de28 ("gpio: zynq: Add support for suspend resume")
Signed-off-by: Swapna Manupati <swapna.manupati@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Srinivas Neeli <srinivas.neeli@xilinx.com>
Link: https://lore.kernel.org/r/1577362338-28744-2-git-send-email-srinivas.neeli@xilinx.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
It's hard for occasional GPIO code reader/writer to know if values 0/1
equal to IN or OUT. Use defined GPIO_LINE_DIRECTION_IN and
GPIO_LINE_DIRECTION_OUT to help them out.
NOTE - for gpio-amd-fch and gpio-bd9571mwv:
This commit also changes the return value for direction get to equal 1
for direction INPUT. Prior this commit these drivers might have
returned some other positive value but 1 for INPUT.
Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Acked-by: Scott Branden <scott.branden@broadcom.com>
Reviewed-by: Grygorii Strashko <grygorii.strashko@ti.com>
Reviewed-by: Michal Simek <michal.simek@xilinx.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: William Breathitt Gray <vilhelm.gray@gmail.com>
Acked-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
We need to convert all old gpio irqchips to pass the irqchip
setup along when adding the gpio_chip. For more info see
drivers/gpio/TODO.
For chained irqchips this is a pretty straight-forward
conversion.
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Cc: Thierry Reding <treding@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20190809132649.25176-1-linus.walleij@linaro.org
We don't need dev_err() messages when platform_get_irq() fails now that
platform_get_irq() prints an error message itself when something goes
wrong. Let's remove these prints with a simple semantic patch.
// <smpl>
@@
expression ret;
struct platform_device *E;
@@
ret =
(
platform_get_irq(E, ...)
|
platform_get_irq_byname(E, ...)
);
if ( \( ret < 0 \| ret <= 0 \) )
{
(
-if (ret != -EPROBE_DEFER)
-{ ...
-dev_err(...);
-... }
|
...
-dev_err(...);
)
...
}
// </smpl>
While we're here, remove braces on if statements that only have one
statement (manually).
Cc: linux-gpio@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20190730181557.90391-16-swboyd@chromium.org
Acked-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Based on 1 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-or-later
has been chosen to replace the boilerplate/reference in 3029 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use the new helper that wraps the calls to platform_get_resource()
and devm_ioremap_resource() together.
Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The Zynq GPIO driver currently implements runtime PM by:
- Enabling runtime PM support in ->probe() and letting the runtime PM
reference counter drop to zero at the end of ->probe().
- Increasing the runtime PM reference counter in ->request() and
decreasing it in ->free().
However, the latter is not sufficient: when a GPIO is used as an
interrupt, ->request() and ->free() are not called. Due to this, the
runtime PM counter remains to zero when the only GPIOs in use are used
as interrupts, causing them to simply not work.
To address this problem, this commit implement the
->irq_request_resources() and ->irq_release_resources() hooks,
ensuring that the runtime PM counter is properly
incremented/decremented. Since we override the default hooks, we keep
the existing behavior by making sure they call gpiochip_reqres_irq() /
gpiochip_relres_irq() respectively.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Reviewed-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The Zynq's gpios can be configured by the bootloader. But Linux will
erroneously report all gpios as inputs unless we implement
get_direction().
Signed-off-by: Brandon Maier <Brandon.Maier@collins.com>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
We should get 'driver_data' from 'struct device' directly. Going via
platform_device is an unneeded step back and forth.
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
In past Xilinx gpio-zynq driver was setting up gpio chip->base as 0
which was chagned to autodetection when driver was upstreamed. Older
systems, which were using this old version, setup SW stack which expects
zynq gpio base as 0 and right now there is no way how to set this up.
The patch is adding an option to setup chip->base based on aliases which
is something what some other drivers are doing too.
It means when gpio0 alias is setup then chip->base is 0. When gpio alias
is not setup gpiochip_find_base() set it up properly which is current
behavior.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Get the driver data directly by dev_get_drvdata.
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Reviewed-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Remove the call to platform_get_irq use the cached
one instead.
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Reviewed-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
In order to consolidate the multiple ways to associate an IRQ chip with
a GPIO chip, move more fields into the new struct gpio_irq_chip.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Acked-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Fix function parameters alignment reported by checkpatch.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This patch fixes the below warning
-->Block comments should align the * on each line.
-->suspect code indent for conditional statements.
-->Prefer 'unsigned int' to bare use of 'unsigned'
Signed-off-by: Nava kishore Manne <navam@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Remove one additional line and add two new. All are reported by checkpatch.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This patch fixes the kernel doc warnings in the driver.
Signed-off-by: Nava kishore Manne <navam@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This patch provides workaround in the gpio driver
for Zynq and ZynqMP Platforms by reading pin value
of EMIO banks through DATA register as it was unable
to read the value of it from DATA_RO register.
Signed-off-by: Swapna Manupati <swapnam@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Add support for suspend resume. Now that we can lose context across
a suspend/ resume cycle. Add support for the context restore.
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The one quirk used in the zynq GPIO driver was called FOO which is not
very descriptive. Rename the quirk to IS_ZYNQ as it indicates whether
the HW is a zynq or zynqmp device to allow handling of device-specific
differences of the HW.
Also provide a helper function to test whether the HW is zynq or zynqmp.
Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This patch adds zynq specific check for bank 0 pins 7 and 8
are special and cannot be used as inputs
Signed-off-by: Nava kishore Manne <navam@xilinx.com>
Reported-by: Jonas Karlsson <Jonas.d.karlsson@gmail.com>
Acked-by: Sören Brinkmann <soren.brinkmann@xilinx.com>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
When the PM initialization was moved in the commit referenced below, the
code enabling the clock was removed from the probe function. On
CONFIG_PM=y kernels, this is not a problem as the pm resume hook enables
the clock, but when power management is disabled, all those pm_*
functions are noops and the clock is never enabled resulting in a
dysfunctional gpio controller.
Put the clock initialization back to support CONFIG_PM=n.
Cc: stable@vger.kernel.org
Signed-off-by: Helmut Grohne <h.grohne@intenta.de>
Fixes: 3773c195d3 ("gpio: zynq: Do PM initialization earlier to support gpio hogs")
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
pm_runtime_disable is called only in remove it is missed
out in the error path.
Fix the same.
Signed-off-by: Shubhrajyoti Datta <shubhraj@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This makes the driver use the data pointer added to the gpio_chip
to store a pointer to the state container instead of relying on
container_of().
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Sören Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
GPIO hogs registration is call at the end of gpiochip_add() function.
Calling sequence is:
gpiochip_add -> of_gpiochip_add -> of_gpiochip_scan_hogs ->
gpiod_hog -> gpiochip_request_own_desc -> __gpiod_request ->
chip->request -> zynq_gpio_request which calls pm_runtime_get_sync()
which returns -13 because PM is not initialized yet.
Initialize PM before gpiochip_add is called to fix this issue.
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The name .dev in a struct is normally reserved for a struct device
that is let us say a superclass to the thing described by the struct.
struct gpio_chip stands out by confusingly using a struct device *dev
to point to the parent device (such as a platform_device) that
represents the hardware. As we want to give gpio_chip:s real devices,
this is not working. We need to rename this member to parent.
This was done by two coccinelle scripts, I guess it is possible to
combine them into one, but I don't know such stuff. They look like
this:
@@
struct gpio_chip *var;
@@
-var->dev
+var->parent
and:
@@
struct gpio_chip var;
@@
-var.dev
+var.parent
and:
@@
struct bgpio_chip *var;
@@
-var->gc.dev
+var->gc.parent
Plus a few instances of bgpio that I couldn't figure out how
to teach Coccinelle to rewrite.
This patch hits all over the place, but I *strongly* prefer this
solution to any piecemal approaches that just exercise patch
mechanics all over the place. It mainly hits drivers/gpio and
drivers/pinctrl which is my own backyard anyway.
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Rafał Miłecki <zajec5@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Cc: Alek Du <alek.du@intel.com>
Cc: Jaroslav Kysela <perex@perex.cz>
Cc: Takashi Iwai <tiwai@suse.com>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Acked-by: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Acked-by: Jacek Anaszewski <j.anaszewski@samsung.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The state container of the Zynq GPIO driver is sometimes
extracted from the gpio_chip exploiting the fact that offsetof()
the struct gpio_chip inside the struct zynq_gpio is 0, so
the container_of() is in practice a noop. However if a member
is added to struct zynq_gpio in front of struct gpio_chip,
things will break. Using proper container_of() avoids this
problem.
Semantically this is a noop, the compiler will optimize it away,
but syntactically it makes me happier.
Also replace some explicit container_of() calls with the helper
function.
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Ezra Savard <ezra.savard@xilinx.com>
Cc: Michal Simek <michal.simek@xilinx.com>
Acked-by: Harini Katakam <harinik@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Most interrupt flow handlers do not use the irq argument. Those few
which use it can retrieve the irq number from the irq descriptor.
Remove the argument.
Search and replace was done with coccinelle and some extra helper
scripts around it. Thanks to Julia for her help!
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Jiang Liu <jiang.liu@linux.intel.com>
This driver is tristate, so it should be cleanable.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Tested-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Use irq_desc_get_xxx() to avoid redundant lookup of irq_desc while we
already have a pointer to corresponding irq_desc.
Preparatory patch for the removal of the 'irq' argument from irq flow
handlers.
Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Alexandre Courbot <gnurou@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Hand in irq_data and avoid the redundant lookup of irq_desc.
Originally-from: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Added support to Zynq Ultrascale+ MPSoC on the existing zynq
gpio driver.
Signed-off-by: Anurag Kumar Vulisha <anuragku@xilinx.com>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The SET_PM_RUNTIME_PM_OPS() and SET_RUNTIME_PM_OPS() macros are
identical except that one of them is not empty for CONFIG_PM set,
while the other one is not empty for CONFIG_PM_RUNTIME set,
respectively.
However, after commit b2b49ccbdd (PM: Kconfig: Set PM_RUNTIME if
PM_SLEEP is selected) PM_RUNTIME is always set if PM is set, so one
of these macros is now redundant.
For this reason, replace SET_PM_RUNTIME_PM_OPS() with
SET_RUNTIME_PM_OPS() everywhere and redefine the SET_PM_RUNTIME_PM_OPS
symbol as SET_RUNTIME_PM_OPS in case new code is starting to use the
macro being removed here.
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Kevin Hilman <khilman@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Some drivers accidentally still use the return value from
gpiochip_remove(). Get rid of them so we can simplify this function
and get rid of the return value.
Cc: Abdoulaye Berthe <berthe.ab@gmail.com>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-by: Javier Martinez Canillas <javier@dowhile0.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
this remove all reference to gpio_remove retval in all driver
except pinctrl and gpio. the same thing is done for gpio and
pinctrl in two different patches.
Signed-off-by: Abdoulaye Berthe <berthe.ab@gmail.com>
Acked-by: Michael Büsch <m@bues.ch>
Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Acked-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
Acked-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Use of unmask/mask in set_wake was an incorrect implementation. The new
implementation correctly sets wakeup for the gpio chip's IRQ so the gpio chip
will not sleep while wakeup-enabled gpio are in use.
Signed-off-by: Ezra Savard <ezra.savard@xilinx.com>
Reviewed-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Added flag to the GPIO chip so that IRQ from non-wakeup GPIO will
not wake the system.
Signed-off-by: Ezra Savard <ezra.savard@xilinx.com>
Reviewed-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
When looking up the IRQ the bank offset needs to be taken into account.
Otherwise interrupts for banks other than bank 0 get incorrectly reported as
interrupts for bank 0.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
zynq_gpio_irqhandler() uses up to 7 tabs of indention in some parts. Refactor
things to use a helper function for the inner loop to reduce the indention to a
sane level.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
There is no need to init .owner field.
Based on the patch from Peter Griffin <peter.griffin@linaro.org>
"mmc: remove .owner field for drivers using module_platform_driver"
This patch removes the superflous .owner field for drivers which
use the module_platform_driver API, as this is overriden in
platform_driver_register anyway."
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The Zynq GPIO interrupt handling code as two main issues:
1) It does not support IRQF_ONESHOT interrupt since it uses handle_simple_irq()
for the interrupt handler. handle_simple_irq() does not do masking and unmasking
of the IRQ that is required for this chip to be able to support IRQF_ONESHOT
IRQs, causing the CPU to lock up in a interrupt storm if such a interrupt is
requested.
2) Interrupts are acked after the primary interrupt handlers for all asserted
interrupts in a bank have been called. For edge triggered interrupt this is to
late and may cause a interrupt to be missed. For level triggered oneshot
interrupts this is to early and causes the interrupt handler to run twice per
interrupt.
This patch addresses the issue by updating the driver to use the correct IRQ
chip handler functions that are appropriate for this kind of IRQ controller.
The following diagram gives an overview of how the interrupt detection circuit
works, it is not necessarily a accurate depiction of the real hardware though.
INT_POL/INT_ON_ANY
|
| +---+ INT_STATUS
`-| | |
| E |-. |
,---| | \ |\ +----+ | +---+
| +---+ `----| | ,-------|S | ,*--| |
GPIO_IN -* | |- | Q|- | & |-- IRQ_OUT
| +---+ ,-----| | ,-|R | ,o| |
`---| | / |/ | +----+ | +---+
| = |- | | |
,-| | INT_TYPE ACK INT_MASK
| +---+
|
INT_POL
GPIO_IN is the raw signal level connected to the hardware pin. This signal is
routed to a edge detector and to a level detector. The edge detector can be
configured to either detect a rising or falling edge or both edges. The level
detector can detect either a level high or level low event. Depending on the
setting of the INT_TYPE register either the edge or level event will be
propagated to the INT_STATUS register. As long as a interrupt condition is
detected the INT_STATUS register will be set to 1. It can be cleared to 0 if
(and only if) the interrupt condition is no longer detected and software
acknowledges the interrupt by writing a 1 to the address of the INT_STATUS
register. There is also the INT_MASK register which can be used to disable the
propagation of the INT_STATUS signal to the upstream IRQ controller. What is
important to note is that the interrupt detection logic itself can not be
disabled, only the propagation of the INT_STATUS register can be delayed. This
means that for level type interrupts the interrupt must only be acknowledged
after the interrupt source has been cleared otherwise it will stay asserted and
the interrupt handler will be run a second time. For IRQF_ONESHOT interrupts
this means that the IRQ must only be acknowledged after the threaded interrupt
has finished running. If a second interrupt comes in between handling the first
interrupt and acknowledging it the external interrupt will be asserted, which
means trying to acknowledge the first interrupt will not clear the INT_STATUS
register and the interrupt handler will be run a second time when the IRQ is
unmasked, so no interrupts will be lost. The handle_fasteoi_irq() handler in
combination with the IRQCHIP_EOI_THREADED | IRQCHIP_EOI_IF_HANDLED flags will
have the desired behavior. For edge triggered interrupts a slightly different
strategy is necessary. For edge triggered interrupts the interrupt condition is
only true when the edge itself is detected, this means this is the only time the
INT_STATUS register is set, acknowledging the interrupt any time after that will
clear the INT_STATUS register until the next interrupt happens. This means in
order to not loose any interrupts the interrupt needs to be acknowledged before
running the interrupt handler. If a second interrupt occurs after the first
interrupt handler has finished but before the interrupt is unmasked the
INT_STATUS register will be re-asserted and the interrupt handler runs a second
time once the interrupt is unmasked. This means with this flow handling strategy
no interrupts are lost for edge triggered interrupts. The handle_level_irq()
handler will have the desired behavior. (Note: The handle_edge_irq() only needs
to be used for edge triggered interrupts where the controller stops detecting
the interrupt event when the interrupt is masked, for this controller the
detection logic still works, while only the propagation is delayed when the
interrupt is masked.)
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The Zynq GPIO controller does not disable the interrupt detection when the
interrupt is masked and only disables the propagation of the interrupt. This
means when the controller detects an interrupt condition while the interrupt is
logically disabled (and masked) it will propagate the recorded interrupt event
once the interrupt is enabled. This will cause the interrupt consumer to see
spurious interrupts to prevent this first make sure that the interrupt is not
asserted and then enable it.
E.g. when a interrupt is requested with request_irq() it will be configured
according to the requested type (edge/level triggered, etc.) after that it will
be enabled. But the detection circuit might have already registered a false
interrupt before the interrupt type was correctly configured and once the
interrupt is unmasked this false interrupt will be propagated and the interrupt
handler for the just request interrupt will called.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Add support for GPIO controller used by Xilinx Zynq.
v3 changes:
- Use linux/gpio/driver.h instead of linux/gpio.h
- Make irq a local variable in probe
v2 changes:
- convert to pm_runtime_force_(suspend|resume)
- add pm_runtime_set_active in probe()
- also (un)prepare clocks when they are dis-/enabled
- add some missing calls to pm_runtime_get()
- use pm_runtime_put() instead of sync variant
- remove gpio chip in driver remove()
- remove redundant type casts
- directly use IO helpers
- use BIT macro to set/clear bits
- migrate to GPIOLIB_IRQCHIP
Signed-off-by: Harini Katakam <harinik@xilinx.com>
Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>