kernel series:
- A big set of cleanups to the aged sysfs interface from
Johan Hovold. To get these in, v4.1-rc3 was merged into
the tree as the first patch in that series had to go
into stable. This makes the locking much more fine-grained
(get rid of the "big GPIO lock(s)" and store states in the
GPIO descriptors.
- Rename gpiod_[g|s]et_array() to gpiod_[g|s]et_array_value()
to avoid confusions.
- New drivers for:
- NXP LPC18xx (currently LPC1850)
- NetLogic XLP
- Broadcom STB SoC's
- Axis ETRAXFS
- Zynq Ultrascale+ (subdriver)
- ACPI:
- Make it possible to retrieve GpioInt resources from
a GPIO device using acpi_dev_gpio_irq_get()
- Merge some dependent I2C changes exploiting this.
- Support the ARM X-Gene GPIO standby driver.
- Make it possible for the generic GPIO driver to read
back the value set registers to reflect current
status.
- Loads of OMAP IRQ handling fixes.
- Incremental improvements to Kona, max732x, OMAP, MXC, RCAR,
PCA953x, STP-XWAY, PCF857x, Crystalcove, TB10x.
- Janitorial (contification, checkpatch cleanups)
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Merge tag 'gpio-v4.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio
Pull gpio updates from Linus Walleij:
"This is the big bulk of GPIO changes queued for the v4.2 kernel
series:
- a big set of cleanups to the aged sysfs interface from Johan
Hovold. To get these in, v4.1-rc3 was merged into the tree as the
first patch in that series had to go into stable. This makes the
locking much more fine-grained (get rid of the "big GPIO lock(s)"
and store states in the GPIO descriptors.
- rename gpiod_[g|s]et_array() to gpiod_[g|s]et_array_value() to
avoid confusions.
- New drivers for:
* NXP LPC18xx (currently LPC1850)
* NetLogic XLP
* Broadcom STB SoC's
* Axis ETRAXFS
* Zynq Ultrascale+ (subdriver)
- ACPI:
* make it possible to retrieve GpioInt resources from a GPIO
device using acpi_dev_gpio_irq_get()
* merge some dependent I2C changes exploiting this.
* support the ARM X-Gene GPIO standby driver.
- make it possible for the generic GPIO driver to read back the value
set registers to reflect current status.
- loads of OMAP IRQ handling fixes.
- incremental improvements to Kona, max732x, OMAP, MXC, RCAR,
PCA953x, STP-XWAY, PCF857x, Crystalcove, TB10x.
- janitorial (constification, checkpatch cleanups)"
* tag 'gpio-v4.2-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio: (71 commits)
gpio: Fix checkpatch.pl issues
gpio: pcf857x: handle only enabled irqs
gpio / ACPI: Return -EPROBE_DEFER if the gpiochip was not found
GPIO / ACPI: export acpi_gpiochip_request(free)_interrupts for module use
gpio: improve error reporting on own descriptors
gpio: promote own request failure to pr_err()
gpio: Added support to Zynq Ultrascale+ MPSoC
gpio: add ETRAXFS GPIO driver
fix documentation after renaming gpiod_set_array to gpiod_set_array_value
gpio: Add GPIO support for Broadcom STB SoCs
gpio: xgene: add ACPI support for APM X-Gene GPIO standby driver
gpio: tb10x: Drop unneeded free_irq() call
gpio: crystalcove: set IRQCHIP_SKIP_SET_WAKE for the irqchip
gpio: stp-xway: Use the of_property_read_u32 helper
gpio: pcf857x: Check for irq_set_irq_wake() failures
gpio-stp-xway: Fix enabling the highest bit of the PHY LEDs
gpio: Prevent an integer overflow in the pca953x driver
gpio: omap: rework omap_gpio_irq_startup to handle current pin state properly
gpio: omap: rework omap_gpio_request to touch only gpio specific registers
gpio: omap: rework omap_x_irq_shutdown to touch only irqs specific registers
...
Pull irq updates from Thomas Gleixner:
"The irq departement delivers:
- plug a potential race related to chained interrupt handlers
- core updates which address the needs of the x86 irqdomain conversion
- new irqchip callback to support affinity settings for VCPUs
- the usual pile of updates to interrupt chip drivers
- a few helper functions to allow further cleanups and
simplifications
I have a largish pile of coccinelle scripted/verified cleanups and
simplifications pending on top of that, but I prefer to send that
towards the end of the merge window when the arch/driver changes have
hit your tree to avoid API change wreckage as far as possible"
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (34 commits)
genirq: Remove bogus restriction in irq_move_mask_irq()
irqchip: atmel-aic5: Add sama5d2 support
irq: spear-shirq: Fix race in installing chained IRQ handler
irq: irq-keystone: Fix race in installing chained IRQ handler
gpio: gpio-tegra: Fix race in installing chained IRQ handler
gpio: gpio-mxs: Fix race in installing chained IRQ handler
gpio: gpio-mxc: Fix race in installing chained IRQ handler
ARM: gemini: Fix race in installing GPIO chained IRQ handler
GPU: ipu: Fix race in installing IPU chained IRQ handler
ARM: sa1100: convert SA11x0 related code to use new chained handler helper
irq: Add irq_set_chained_handler_and_data()
irqchip: exynos-combiner: Save IRQ enable set on suspend
genirq: Introduce helper function irq_data_get_affinity_mask()
genirq: Introduce helper function irq_data_get_node()
genirq: Introduce struct irq_common_data to host shared irq data
genirq: Prevent crash in irq_move_irq()
genirq: Enhance irq_data_to_desc() to support hierarchy irqdomain
irqchip: gic: Simplify gic_configure_irq by using IRQCHIP_SET_TYPE_MASKED
irqchip: renesas: intc-irqpin: Improve binding documentation
genirq: Set IRQCHIP_SKIP_SET_WAKE for no_irq_chip
...
Fix a race where a pending interrupt could be received and the handler
called before the handler's data has been setup, by converting to
irq_set_chained_handler_and_data().
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Alexandre Courbot <gnurou@gmail.com>
Cc: Hans Ulli Kroll <ulli.kroll@googlemail.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/E1Z4z0M-0002Sl-Ti@rmk-PC.arm.linux.org.uk
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Fix a race where a pending interrupt could be received and the handler
called before the handler's data has been setup, by converting to
irq_set_chained_handler_and_data().
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Alexandre Courbot <gnurou@gmail.com>
Cc: Hans Ulli Kroll <ulli.kroll@googlemail.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/E1Z4z0H-0002Sf-P9@rmk-PC.arm.linux.org.uk
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Fix a race where a pending interrupt could be received and the handler
called before the handler's data has been setup, by converting to
irq_set_chained_handler_and_data().
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Cc: Alexandre Courbot <gnurou@gmail.com>
Cc: Hans Ulli Kroll <ulli.kroll@googlemail.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Lee Jones <lee.jones@linaro.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/E1Z4z0C-0002SX-Lj@rmk-PC.arm.linux.org.uk
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This patch fixes some issues given by checkpatch. Fixes include
bracket placement, spacing and indenting.
Signed-off-by: Daniel Lockyer <thisisdaniellockyer@gmail.com>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Now pcf857x_irq() IRQ's dispatcher will try to run nested
IRQ handlers for each GPIO pin which state has changed.
Such IRQs are, actually, spurious and nested IRQ handlers
have to be called only for IRQs wich were enabled by users.
This is not critical issue - just /proc/interrupts
will display counters for unused IRQS:
399: 4 0 pcf857x 0 Edge
428: 1 0 pcf857x 13 Edge
430: 1 0 pcf857x 15 Edge
Hence, fix it by adding irq_enabled field in struct pcf857x to track
enabled GPIO IRQs and corresponding callbacks in pcf857x_irq_chip.
Similar functionality was presented in pcf857x driver, commit
21fd3cd187 ('gpio: pcf857x: call the gpio user handler iff...')
and then it was removed by commit
a39294bdf4 ('gpio: pcf857x: Switch to use gpiolib irqchip...')
Cc: Geert Uytterhoeven <geert+renesas@glider.be>
Fixes: a39294bdf4 ('gpio: pcf857x: Switch to use gpiolib irqchip helpers')
Signed-off-by: Grygorii Strashko <grygorii.strashko@ti.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
If a driver requests a GPIO described in its _CRS but the GPIO host
controller (gpiochip) driver providing the GPIO has not been loaded yet
acpi_get_gpiod() returns -ENODEV which causes the calling driver to fail.
If the gpiochip driver is loaded afterwards the driver requesting the GPIO
will not notice this.
Better approach is to return -EPROBE_DEFER in such case. Then when the
gpiochip driver appears the driver requesting the GPIO will be probed
again. This also aligns ACPI GPIO lookup code closer to DT as it does
pretty much the same when no gpiochip driver was found.
Reported-by: Tobias Diedrich <tobiasdiedrich@gmail.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Tobias Diedrich <ranma+kernel@tdiedrich.de>
Reviewed-by: Amos Kong <kongjianjun@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
acpi_gpiochip_request(free)_interrupts can be used for modules,
so export them. This also fixs a compile error when xgene-sb
configured as kernel module.
Fixes: 733cf014f0 "gpio: xgene: add ACPI support for APM X-Gene GPIO standby driver"
Reviewed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
When requesting own descriptors through hogs, it is useful to
get some details about what's going on if we encounter problems.
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
These error messages are helpful to see that we fail to get
hogs. Promote them to real errors so they appear in the boot
crawl.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
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>
Add a GPIO driver for the General I/O block on Axis ETRAX FS SoCs.
Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This adds support for the GPIO IP "UPG GIO" used on
Broadcom STB SoCs (BCM7XXX and some others). Uses
basic_mmio_gpio to instantiate a gpio_chip for each bank.
The driver assumes that it handles the base set of GPIOs
on the system and that it can start its numbering sequence
from 0, so any GPIO expanders used with it must dynamically
assign GPIO numbers after this driver has finished
registering its GPIOs.
Does not implement the interrupt-controller portion yet,
will be done in a future commit.
v2:
- change include to use <linux/gpio/driver.h> instead of
<linux/gpio.h>
- get rid of unnecessary imask member in struct bank
- rename GPIO_PER_BANK -> MAX_GPIO_PER_BANK
- always have 32 GPIOs per bank and add 'width' member in
struct bank to hold actual number of GPIOs in use
- mark of_match table as const
List-usage-fixed-by: Brian Norris <computersforpeace@gmail.com>
Signed-off-by: Gregory Fong <gregory.0xf0@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Current code uses devm_request_irq() in .probe, so drop the unneeded
free_irq() call in .remove.
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Christian Ruppert <christian.ruppert@alitech.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The CrystalCove GPIO irqchip doesn't have irq_set_wake callback defined
so we should set IRQCHIP_SKIP_SET_WAKE for it or it would cause an irq
desc's wake_depth unbalanced warning during system resume phase from the
gpio_keys driver, which is the driver for the power button of the ASUS
T100 laptop.
Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This removes some redundant code but does not have any functional impact.
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
If an interrupt controller doesn't support wake-up configuration,
irq_set_irq_wake() returns an error code. Then any subsequent call
trying to deconfigure wake-up will cause an imbalance, and a warning
will be printed:
WARNING: CPU: 1 PID: 1341 at kernel/irq/manage.c:540 irq_set_irq_wake+0x
Unbalanced IRQ 26 wake disable
To fix this, refrain from any further parent interrupt controller
(de)configuration if irq_set_irq_wake() failed.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
0x3 only masks two bits, but three bits have to be allowed. This fixes
GPHY0 LED2 (which is the highest bit of phy2) on my board.
Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Acked-by: John Crispin <blogic@openwrt.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Interrupts were missed if an 8-bit integer overflow occurred. This was
observed when bank0,pin7 and bank1,pin7 changed simultaniously.
As the 8-bit totals were only checked against zero, replace them with
booleans. Name the booleans so that their purpose is clear.
Signed-off-by: Joshua Scott <joshua.scott@alliedtelesis.co.nz>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The omap_gpio_irq_startup() can be called at time when:
- corresponding GPIO has been requested already and in this case
it has to be configured as input already. If not - return with -EINVAL
and do not try to re-configure it as it could be unsafe.
- corresponding GPIO is free: reconfigure GPIO as input.
In addition, call omap_enable_gpio_module directly as all needed
checks are already present inside it.
Signed-off-by: Grygorii Strashko <grygorii.strashko@linaro.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The GPIO Chip and GPIO IRQ Chip functionality are essentially orthogonal,
so GPIO Chip implementation shouldn't touch GPIO IRQ specific registers
and vise versa.
Hence, rework omap_gpio_request:
- don't reset GPIO IRQ triggering type to IRQ_TYPE_NONE, because
GPIO irqchip should be responsible for that;
- call directly omap_enable_gpio_module as all needed checks are already
present inside it.
Signed-off-by: Grygorii Strashko <grygorii.strashko@linaro.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The GPIO Chip and GPIO IRQ Chip functionality are essentially orthogonal,
so GPIO IRQ Chip implementation shouldn't touch GPIO specific
registers and vise versa.
Hence, rework omap_gpio_irq_shutdown and try to touch only irqs specific
registers:
- don't configure GPIO as input (it, actually, should be already configured
as input).
- don't clear debounce configuration if GPIO is still used as GPIO.
We need to take in to account here commit c9c55d9211
("gpio/omap: fix off-mode bug: clear debounce settings on free/reset").
Also remove omap_reset_gpio() function as it is not used any more.
Signed-off-by: Grygorii Strashko <grygorii.strashko@linaro.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The GPIO bank will be kept powered in case if input parameters
are invalid or error occurred in omap_gpio_irq_type.
Hence, fix it by ensuring that GPIO bank will be unpowered
in case of errors and add additional check of value returned
from omap_set_gpio_triggering().
Signed-off-by: Grygorii Strashko <grygorii.strashko@linaro.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This patch fixes following issue:
- GPIOn is used as IRQ by some dev, for example PCF8575.INT -> gpio6.11
- PCFx driver knows nothing about type of IRQ line (GPIO or not)
so it doesn't request gpio and just do request_irq()
- If gpio6.11 will be exported through the sysfs and then un-xeported
then IRQs from PCFx will not be received any more, because
IRQ configuration for gpio6.11 will be cleaned up unconditionally
in omap_gpio_free.
Fix this by removing all GPIO IRQ specific code from omap_gpio_free()
and also do GPIO clean up (change direction to 'in' and disable debounce)
only if corresponding GPIO is not used as IRQ too.
GPIO IRQ will be properly cleaned up by GPIO irqchip code.
Signed-off-by: Grygorii Strashko <grygorii.strashko@linaro.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
If an interrupt controller doesn't support wake-up configuration,
irq_set_irq_wake() returns an error code. Then any subsequent call
trying to deconfigure wake-up will cause an imbalance, and a warning
will be printed:
WARNING: CPU: 1 PID: 1341 at kernel/irq/manage.c:540 irq_set_irq_wake+0x9c/0xf8()
Unbalanced IRQ 26 wake disable
To fix this, refrain from any further parent interrupt controller
(de)configuration if irq_set_irq_wake() failed.
Alternative fixes would be:
- calling "gic_set_irqchip_flags(IRQCHIP_SKIP_SET_WAKE)" from the
platform code,
- setting "gic_chip.flags = IRQCHIP_SKIP_SET_WAKE" in the GIC driver
code,
but these were withheld as the GIC hardware doesn't really support
wake-up interrupts.
Fixes: ab82fa7da4 ("gpio: rcar: Prevent module clock disable when wake-up is enabled")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
There have been concerns that the function names gpiod_set_array() and
gpiod_get_array() might be confusing to users. One might expect
gpiod_get_array() to return array values, while it is actually the array
counterpart of gpiod_get(). To be consistent with the single descriptor API
we could rename gpiod_set_array() to gpiod_set_array_value(). This makes
some function names a bit lengthy: gpiod_set_raw_array_value_cansleep().
Signed-off-by: Rojhalat Ibrahim <imr@rtschenk.de>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Clean up chained handler and handler data if they were set by
gpiochip_set_chained_irqchip().
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The dln2 driver was initialising a gpiolib private field, which is now
gone.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This patch fixes an inverted return value of the gpio get_direction
function.
The wrong value causes the direction sysfs entry and GPIO debugfs file
to indicate incorrect GPIO direction settings. In some cases it also
prevents setting GPIO output values.
The problem is also present in all other stable kernel versions since
linux-3.12.
Cc: Stable <stable@vger.kernel.org> # v3.12+
Reported-by: Jochen Henneberg <jh@henneberg-systemdesign.com>
Signed-off-by: Michael Brunner <michael.brunner@kontron.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Make sure to free any hogged gpios on errors in gpiochip_add.
Also move all forward declarations to the top of the file.
Fixes: f625d46017 ("gpio: add GPIO hogging mechanism")
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Move irq trigger flags, which as sysfs-interface specific, to the class
device data.
This avoids accessing the gpio-descriptor flags field using non-atomic
operations without any locking, and allows for a more clear separation
of the sysfs interface from gpiolib core.
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Remove FLAG_SYSFS_DIR, which is sysfs-interface specific, and store it
in the class-device data instead.
Note that the flag is only used during export.
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Rename active-low helper using common prefix.
Also remove unnecessary manipulation of value argument.
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Make sure to deregister the class device (and release the irq) while
holding the sysfs lock in gpio_unexport to prevent racing with
gpio_export.
Note that this requires the recently introduced per-gpio locking to
avoid a deadlock with the kernfs active protection when waiting for the
attribute operations to drain during deregistration.
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Add a per-gpio mutex to serialise attribute operations rather than use
one global mutex for all gpios and chips.
Having a single global lock for all gpios in a system adds unnecessary
latency to the sysfs interface, and especially when having gpio
controllers connected over slow buses.
Now that the global gpio-sysfs interrupt table is gone and with per-gpio
data in place, we can easily switch to using a more fine-grained locking
scheme.
Keep the global mutex to serialise the global (class) operations of gpio
export and unexport and chip removal.
Also document the locking assumptions made.
Note that this is also needed to fix a race between gpiod_export and
gpiod_unexport.
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Drop unnecessary locking from gpiod_export_link. If the class device has
not already been unregistered, class_find_device returns the ref-counted
class device so there's no need for locking.
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Only call irq helper if actually reconfiguring interrupt state.
This is a preparatory step in introducing separate gpio-irq request and
free functions.
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Store the value sysfs entry in the gpiod data rather than in a global
table accessed through an index stored in the overloaded gpio-descriptor
flag field.
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Add gpiod class-device data.
This is a first step in getting rid of the insane gpio-descriptor flag
overloading, backward irq-interface implementation, and course grained
sysfs-interface locking (a single static mutex for every operation on
all exported gpios in a system).
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The attribute operations will never be called for an unregistered device
so remove redundant checks for FLAG_EXPORT.
Note that kernfs will also guarantee that any active sysfs operation has
finished before the attribute is removed during deregistration.
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Make sure to release any irq only after the class device has been
deregistered.
This avoids a race between gpiod_unexport and edge_store, where an irq
could be allocated just before the gpio class device is deregistered
without relying on FLAG_EXPORT and the global sysfs lock.
Note that there is no need to hold the sysfs lock when releasing the irq
after the class device is gone as kernfs will prevent further attribute
operations.
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Use DEVICE_ATTR_RO and DEVICE_ATTR_RW rather than specifying masks and
callbacks directly.
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Remove gpiod_sysfs_set_active_low (and gpio_sysfs_set_active_low) which
allowed code to change the polarity of a gpio line even after it had
been exported through sysfs.
Drivers should not care, and generally does not know, about gpio-line
polarity which is a hardware feature that needs to be described by
firmware.
It is currently possible to define gpio-line polarity in device-tree and
acpi firmware or using platform data. Userspace can also change the
polarity through sysfs.
Note that drivers using the legacy gpio interface could still use
GPIOF_ACTIVE_LOW to change the polarity before exporting the gpio.
There are no in-kernel users of this interface.
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Harry Wei <harryxiyou@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@zh-kernel.org
Cc: linux-arch@vger.kernel.org
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
