Small clean up for Intel PMIC GPIO drivers, includes:
- optimizing IRQ handlers by usage of for_each_set_bit()
- sorting headers alphabetically for better maintenance
- conversion to SPDX identifier
The following is an automated git shortlog grouped by driver:
crystalcove:
- Convert to use SPDX identifier
- Sort headers alphabetically
- Use for_each_set_bit() in IRQ handler
msic:
- Convert to use SPDX identifier
- Sort headers alphabetically
- Remove duplicate check in IRQ handler
wcove:
- Convert to use SPDX identifier
- Fix indentation
- Sort headers alphabetically
- Allow return negative error code from to_reg()
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Merge tag 'intel-gpio-v5.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/andy/linux-gpio-intel into devel
intel-gpio for v5.1-1
Small clean up for Intel PMIC GPIO drivers, includes:
- optimizing IRQ handlers by usage of for_each_set_bit()
- sorting headers alphabetically for better maintenance
- conversion to SPDX identifier
The following is an automated git shortlog grouped by driver:
crystalcove:
- Convert to use SPDX identifier
- Sort headers alphabetically
- Use for_each_set_bit() in IRQ handler
msic:
- Convert to use SPDX identifier
- Sort headers alphabetically
- Remove duplicate check in IRQ handler
wcove:
- Convert to use SPDX identifier
- Fix indentation
- Sort headers alphabetically
- Allow return negative error code from to_reg()
- 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
Change the coding style to make it does error checking first.
This also fixes checkpatch warning about line over 80 characters.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Tested by: Thor Thayer <thor.thayer@linux.intel.com>
Reviewed by: Thor Thayer <thor.thayer@linux.intel.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
The new prefix allows the GPIOs to be uniquely identified on a per-chip
basis, which makes it easier to distinguish Tegra186 specific GPIOs from
those of later chips such as Tegra194 which supports a very different
set of GPIOs.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
madera_gpio_chip is only used as a template so it can be marked as const.
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
The NXP PCAL6416, documented at [1], is a variant of the PCA GPIO
expander with 16 GPIOs, and supporting an interrupt and the "extended"
features for interrupt, pull-up/pull-down configuration, etc.
[1] https://www.nxp.com/docs/en/data-sheet/PCAL6416A.pdf
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Unlike gpio_rcar_irq_set_wake(), which this solution was based on,
pcf857x_irq_set_wake() does not need to do anything else than calling
irq_set_irq_wake() for the upstream interrupt controller. Hence there
is no reason for making this call conditional, and no longer a need for
keeping a copy of the interrupt number that also serves as a flag.
Just propagate irq_set_irq_wake() to the upstream interrupt controller,
using the original interrupt number.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Fix the following warning by adding a missing break:
drivers/gpio/gpio-eic-sprd.c: In function ‘sprd_eic_irq_set_type’:
drivers/gpio/gpio-eic-sprd.c:403:3: warning: this statement may fall through [-Wimplicit-fallthrough=]
switch (flow_type) {
^~~~~~
drivers/gpio/gpio-eic-sprd.c:435:2: note: here
default:
^~~~~~~
This patch is part of the ongoing efforts to enable
-Wimplicit-fallthrough.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reviewed-by: Baolin Wang <baolin.wang@linaro.org>
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>
This commit adds a minimal implementation of the ->set_config() hook,
with support for the PIN_CONFIG_BIAS_PULL_UP and
PIN_CONFIG_BIAS_PULL_DOWN configurations.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
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>
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>
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>
Interupts were generated using GPIN interrupts of
ADP5588. These interrupts have two important limitations:
1. Interrupts can only be generated for either rising or
falling edges but not both.
2. Interrupts are reasserted as long as the interrupt condition
persists (i.e. high or low level on that GPIN). This generates
lots of interrupts unless the event is very short.
To overcome this, ADP5588 provides an event system which queues
up to 10 events in a buffer. GPIN events are queued whenever the
GPIN is asserted or deasserted. This makes it possible to support
generating GPIN interrupts for both edges and to generate only one
interrupt per state change.
Thus it is possible to chain the gpio-keys driver for some GPIOs.
Signed-off-by: Nikolaus Voss <nikolaus.voss@loewensteinmedical.de>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Make platform data optional and add DT id table.
Switch to dynamically mapped GPIOs and IRQs if not provided
via platform data.
Signed-off-by: Nikolaus Voss <nikolaus.voss@loewensteinmedical.de>
Acked-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
It's not necessary to remove gpio_chip which added with
devm_gpiochip_add_data().
Fixes: b868db94a6 ("gpio: tqmx86: Add GPIO from for this IO controller")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This adds a driver for Gateworks PLD GPIO, that exist in
two instances on the Gateworks Cambria GW2358-4 router
platform at least.
Cc: Imre Kaloz <kaloz@openwrt.org>
Cc: Tim Harvey <tharvey@gateworks.com>
Reviewed-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reduce size of duplicated comments by switching to use SPDX identifier.
No functional change.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reduce size of duplicated comments by switching to use SPDX identifier.
No functional change.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reduce size of duplicated comments by switching to use SPDX identifier.
No functional change.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
There is no need to check for non-zero pending since for_each_set_bit() does it
on the first iteration.
While here, drop redundant assignment.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
The type of to_reg() is unsigned int while it might return
a negative error code. Callers are also expecting a signed type.
For sake of type consistency replace unsigned int with plain int.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
This simplifies and standardizes the AB IRQ handler by using
the for_each_set_bit() library function.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
On SoC reset all GPIO interrupts are disable. However, if kexec is
used to boot into a new kernel, the SoC does not experience a
reset. Hence GPIO interrupts can be left enabled from the previous
kernel. It is then possible for the interrupt to fire before an
interrupt handler is registered, resulting in the kernel complaining
of an "unexpected IRQ trap", the interrupt is never cleared, and so
fires again, resulting in an interrupt storm.
Disable all GPIO interrupts before registering the GPIO IRQ chip.
Fixes: 7f2691a196 ("gpio: vf610: add gpiolib/IRQ chip driver for Vybrid")
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The checker complains during build
gpiolib-acpi.c:45: warning: Function parameter or member 'irq_requested' not described in 'acpi_gpio_event'
because the typo in the field description.
Fix the name to have documentation up-to-date.
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>
Some TQ-Systems ComExpress modules contain an IO controller with 8
GPIO lines.
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Add missing '*' char to the start of the comment lines.
Signed-off-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
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>
The altr_a10sr_gpio_direction_output should set proper output level
based on the value argument.
Fixes: 26a48c4cc2 ("gpio: altera-a10sr: Add A10 System Resource Chip GPIO support.")
Cc: <stable@vger.kernel.org>
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Tested by: Thor Thayer <thor.thayer@linux.intel.com>
Reviewed by: Thor Thayer <thor.thayer@linux.intel.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
When setting async EIC as IRQ_TYPE_EDGE_BOTH type, we missed to set the
SPRD_EIC_ASYNC_INTMODE register to 0, which means detecting edge signals.
Thus this patch fixes the issue.
Fixes: 25518e024e ("gpio: Add Spreadtrum EIC driver support")
Cc: <stable@vger.kernel.org>
Signed-off-by: Neo Hou <neo.hou@unisoc.com>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Since differnt type EICs have its own data register to read, thus fix the
incorrect data register.
Fixes: 25518e024e ("gpio: Add Spreadtrum EIC driver support")
Cc: <stable@vger.kernel.org>
Signed-off-by: Neo Hou <neo.hou@unisoc.com>
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
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>
When multiple instances of pcf857x chips are present, a fix up
message [1] is printed during the probe of the 2nd and later
instances.
The issue is that the driver is using the same irq_chip data
structure between multiple instances.
Fix this by allocating the irq_chip data structure per instance.
[1] fix up message addressed by this patch
[ 1.212100] gpio gpiochip9: (pcf8575): detected irqchip that is shared with multiple gpiochips: please fix the driver.
Cc: Stable <stable@vger.kernel.org>
Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Basic implementation of driver is used to support Fintek
F81804 & F81966 gpios with custom register set.
Signed-off-by: Steffen Kothe <steffen.kothe.gc1993@googlemail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
R-Car GPIO controller provides two interfaces to set GPIO line output
signal state, and for a particular GPIO line the selected interface is
determined by OUTDTSEL bit value.
At the moment the driver supports only one of two interfaces, namely
OUTDT General Output Register is used to control the output signal.
While this selection is the default one on reset, it is not explicitly
configured on probe, thus it might be possible that kernel and userspace
consumers of a GPIO won't be able to set the wanted GPIO output signal.
Below is a simple test case to reproduce the described problem and
verify this fix in the kernel on H3 ULCB by setting non-default OUTDTSEL
configuration from a bootloader:
u-boot > mw.l 0xe6055440 0x3000 1
...
userspace > echo default-on > /sys/devices/platform/leds/leds/led5/trigger
userspace > echo default-on > /sys/devices/platform/leds/leds/led6/trigger
Signed-off-by: Vladimir Zapolskiy <vladimir_zapolskiy@mentor.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Like the Spreadtrum EIC driver[1], this driver needs to emulate edge
triggered interrupts to support the generic gpio-keys driver.
[1]: https://www.spinics.net/lists/kernel/msg2764576.html
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This patch implements level-triggered IRQs in the Hollywood GPIO driver.
Edge triggered interrupts are not supported in this GPIO controller, so
I moved their emulation into a separate patch.
Signed-off-by: Jonathan Neuschäfer <j.neuschaefer@gmx.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
When a system has two PCA953x GPIO expanders, the kernel complains with:
gpio gpiochip2: (0-0021): detected irqchip that is shared with multiple gpiochips: please fix the driver.
Indeed, there is a single instance of "struct irq_chip" that gets
re-used for both PCA953x instance. This commit moves the "struct
irq_chip" to be part of the "struct pca953x_chip", so that we have one
"struct irq_chip" per PCA953X instance.
As part of this, the name of the irq_chip is also made different on a
per-instance basis, now using the dev_name() of the I2C device. This
changes what is visible in /proc/interrupts.
Before:
47: 0 0 pca953x 10 Edge e0100000.sdhci cd
48: 0 0 pca953x 6 Edge e0101000.sdhci cd
After:
47: 0 0 0-0020 10 Edge e0100000.sdhci cd
48: 2 0 0-0020 6 Edge e0101000.sdhci cd
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The current design of pca953x_irq_setup() is:
if (all conditions to support IRQ are met) {
lots of code to support IRQs, which goes to a serious indentation
level.
}
return 0;
It makes more sense to handle this like this:
if (!all conditions to support IRQ are met)
return 0;
handle IRQ support
This commit does just this change, reducing by one tab the indentation
level of the IRQ setup code. Thanks to this reduced indentation level,
we are less restricted by the 80-column limit, and we can have more
function arguments on the same line.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The Spreadtrum PMIC interrupt controller has no registers to set irq
trigger type, since it is always high level trigger. That means the
PMIC EIC controller as a child device of PMIC INTC does not need to
set the trigger type, so remove it.
Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Set proper output level base on the argument of direction_output.
Also remove sama5d2_piobu_set_direction() as there is only one caller
now.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Fixes the following sparse warning:
drivers/gpio/gpio-pca953x.c:292:28: warning:
symbol 'pca953x_i2c_regmap' was not declared. Should it be static?
Fixes: 4942723276 ("gpio: pca953x: Perform basic regmap conversion")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
__acpi_gpio_update_gpiod_flags purpose is to make the gpiod_flags used
when requesting a GPIO match the restrictions from the ACPI resource,
as stored in acpi_gpio_info.flags.
But acpi_gpio_info.flags only contains direction info, and the
requester may have passed in special non-direction flags like
GPIOD_FLAGS_BIT_NONEXCLUSIVE, which we currently clobber.
This commit modifies __acpi_gpio_update_gpiod_flags to preserve these
special flags, so that a requested of an ACPI GPIO can e.g. pass
GPIOD_FLAGS_BIT_NONEXCLUSIV and have it work as intended.
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
struct gpio_chip documentation recommends to always implement this
callback function.
A more concrete motivation is to be able (in combination with
GPIOD_ASIS) to detect whether the bootloader has changed the state of a
GPIO signal.
Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
