Commit cb464a88e1ed ("gpio: make the gpiochip a real device") call
gpiochip_sysfs_unregister after the gpiochip is empty. It lead to the
following crash:
Quan Nguyen [Wed, 17 Feb 2016 13:15:07 +0000 (20:15 +0700)]
gpio: xgene: Enable X-Gene standby GPIO as interrupt controller
Enable X-Gene standby GPIO controller as interrupt controller to provide
its own resources. This avoids ambiguity where GIC interrupt resource is
use as X-Gene standby GPIO interrupt resource in user driver.
Signed-off-by: Y Vo <yvo@apm.com> Signed-off-by: Quan Nguyen <qnguyen@apm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Linus Walleij [Fri, 12 Feb 2016 21:25:22 +0000 (22:25 +0100)]
gpio: add userspace ABI for GPIO line information
This adds a GPIO line ABI for getting name, label and a few select
flags from the kernel.
This hides the kernel internals and only tells userspace what it
may need to know: the different in-kernel consumers are masked
behind the flag "kernel" and that is all userspace needs to know.
However electric characteristics like active low, open drain etc
are reflected to userspace, as this is important information.
We provide information on all lines on all chips, later on we will
likely add a flag for the chardev consumer so we can filter and
display only the lines userspace actually uses in e.g. lsgpio,
but then we first need an ABI for userspace to grab and use
(get/set/select direction) a GPIO line.
Sample output from "lsgpio" on ux500:
GPIO chip: gpiochip7, "8011e000.gpio", 32 GPIO lines
line 0: unnamed unlabeled
line 1: unnamed unlabeled
(...)
line 25: unnamed "SFH7741 Proximity Sensor" [kernel output open-drain]
line 26: unnamed unlabeled
(...)
Tested-by: Michael Welling <mwelling@ieee.org> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Linus Walleij [Fri, 12 Feb 2016 13:48:23 +0000 (14:48 +0100)]
gpio: store reflect the label to userspace
The gpio_chip label is useful for userspace to understand what
kind of GPIO chip it is dealing with. Let's store a copy of this
label in the gpio_device, add it to the struct passed to userspace
for GPIO_GET_CHIPINFO_IOCTL and modify lsgpio to show it.
Arnd Bergmann [Tue, 16 Feb 2016 15:40:36 +0000 (16:40 +0100)]
gpio: ks8695: remove irq_to_gpio function
The ks8695 gpio driver has its own copy of the irq_to_gpio()
function. This is completely unused in the mainline kernel
after we converted all remaining users several years ago,
so we can remove the definition as well.
Josh Cartwright [Wed, 17 Feb 2016 22:44:15 +0000 (16:44 -0600)]
gpio: use kzalloc to allocate gpio_device
The use of kmalloc() to allocate the gpio_device leaves the contained struct
device object in an unknown state. Calling dev_set_name() on a struct device
of unknown state can trigger the free() of an invalid pointer, as seen in the
following backtrace (collected by Tony Lindgren):
Linus Walleij [Tue, 16 Feb 2016 14:41:42 +0000 (15:41 +0100)]
gpio: create an API to detect open drain/source on lines
My left hand merges code to privatize the descriptor handling
while my right hand merges drivers that poke around and
disrespect with the same gpiolib internals.
So let's expose the proper APIs for drivers to ask the gpiolib
core if a line is marked as open drain or open source and
get some order around things so this driver compiles again.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Nicolas Saenz Julienne <nicolassaenzj@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Nicholas Krause [Wed, 3 Feb 2016 00:17:59 +0000 (19:17 -0500)]
gpio: davinci: Fix possible NULL pointer deference
This fixes a possible NULL pointer deference in the function,
davinci_gpio_probe due to the function, gpio2regs being able
to return a NULL pointer if it rans to get the registers for
the gpio devices on a davinci board. Furthermore if this does
arise return -ENXIO to signal callers that this case has arisen
and avoiding setting the regs or other pointer values on the
Bjorn Helgaas [Tue, 2 Feb 2016 19:53:30 +0000 (13:53 -0600)]
gpio: Remove unused asm/gpio.h files
asm/gpio.h is included only by linux/gpio.h, and then only when the arch
selects ARCH_HAVE_CUSTOM_GPIO_H. Only the following arches select it: arm
avr32 blackfin m68k (COLDFIRE only) sh unicore32.
Remove the unused asm/gpio.h files for the arches that do not select
ARCH_HAVE_CUSTOM_GPIO_H.
This is a follow-on to 7563bbf89d06 ("gpiolib/arches: Centralise
bolierplate asm/gpio.h").
Bjorn Helgaas [Tue, 2 Feb 2016 19:53:23 +0000 (13:53 -0600)]
gpio: Include linux/gpio.h instead of asm/gpio.h
Most arches have an asm/gpio.h that merely includes linux/gpio.h. The
others select ARCH_HAVE_CUSTOM_GPIO_H, and when that's selected,
linux/gpio.h includes asm/gpio.h.
Therefore, code should include linux/gpio.h instead of including asm/gpio.h
directly.
Remove includes of asm/gpio.h, adding an include of linux/gpio.h when
necessary.
This is a follow-on to 7563bbf89d06 ("gpiolib/arches: Centralise
bolierplate asm/gpio.h").
No flags are required for bgpio_init in the TS-4800 gpio driver. This
patch set zero instead. The driver will have the same behaviour since
the & operator between the flags already resulted to zero.
Linus Walleij [Thu, 11 Feb 2016 10:37:48 +0000 (11:37 +0100)]
gpio: move the subdriver data pointer into gpio_device
We move to manage this pointer under gpiolib control rather than
leave it in the subdevice's gpio_chip. We can not NULL it after
gpiochip_remove so at to keep things tight.
Linus Walleij [Thu, 11 Feb 2016 10:03:06 +0000 (11:03 +0100)]
gpio: move the pin ranges into gpio_device
Instead of keeping this reference to the pin ranges in the
client driver-supplied gpio_chip, move it to the internal
gpio_device as the drivers have no need to inspect this.
Linus Walleij [Fri, 12 Feb 2016 08:22:11 +0000 (09:22 +0100)]
pinctrl: sirf/atlas7: stop poking around in GPIO internals
This code is poking around in the gpio_chip:s internal structures
to achieve some kind of pin to GPIO mappings.
- It is wrong to poke around in these structs and the pinctrl
maintainer was stupid to let it pass unnoticed, mea culpa.
- The right interface to use is gpiochip_add_pin_range()
- The code appears unused: the pin control part of the driver
is not adding any ranges, so we're iterating over an empty
list. Maybe it is poking around in some other pin controllers
GPIO ranges, and that's just totally wrong, again use
gpiochip_add_pin_range() and specify the right pin
controller.
Cc: Barry Song <baohua@kernel.org> Cc: Guoying Zhang <Guoying.Zhang@csr.com> Cc: Wei Chen <Wei.Chen@csr.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
By the time request_region is called in the WinSystems WS16C48 GPIO
driver, a corresponding device structure has already been allocated. The
devm_request_region function should be used to help simplify the cleanup
code and reduce the possible points of failure.
By the time request_region is called in the SMSC SCH311x GPIO driver, a
corresponding device structure has already been allocated. The
devm_request_region function should be used to help simplify the cleanup
code and reduce the possible points of failure.
By the time request_region is called in the Intel ICH series GPIO
driver, a corresponding device structure has already been allocated. The
devm_request_region function should be used to help simplify the cleanup
code and reduce the possible points of failure.
Cc: Peter Tyser <ptyser@xes-inc.com> Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com> Reviewed-by: Alexandre Courbot <acourbot@nvidia.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
By the time request_region is called in the AMD 8111 GPIO driver, a
corresponding device structure has already been allocated. The
devm_request_region function should be used to help simplify the cleanup
code and reduce the possible points of failure.
By the time request_region is called in the ACCES 104-IDIO-16 GPIO
driver, a corresponding device structure has already been allocated. The
devm_request_region function should be used to help simplify the cleanup
code and reduce the possible points of failure.
By the time request_region is called in the ACCES 104-IDI-48 GPIO
driver, a corresponding device structure has already been allocated. The
devm_request_region function should be used to help simplify the cleanup
code and reduce the possible points of failure.
By the time request_region is called in the ACCES 104-DIO-48E GPIO
driver, a corresponding device structure has already been allocated. The
devm_request_region function should be used to help simplify the cleanup
code and reduce the possible points of failure.
gpio: misc: Pass correct license string to MODULE_LICENSE
The GPIO driver copyright boilerplate lacks the "or
later" verbiage regarding GPL compliant distribution. The MODULE_LICENSE
string should reflect the actual copyright license terms used.
Signed-off-by: William Breathitt Gray <vilhelm.gray@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Linus Walleij [Thu, 11 Feb 2016 09:28:44 +0000 (10:28 +0100)]
gpio: reference count the gpio device for each desc
Every time a descriptor is retrieved from the gpiolib, we issue
module_get() to reference count the module supplying the GPIOs.
We also need to call device_get() and device_put() as we also
reference the backing gpio_device when doing this.
Since the sysfs GPIO interface is using gpiod_get() this will
also reference count the sysfs requests until all GPIOs are
unexported.
Linus Walleij [Wed, 10 Feb 2016 09:57:36 +0000 (10:57 +0100)]
gpio: reflect base and ngpio into gpio_device
Some information about the GPIO chip need to stay around also
after the gpio_chip has been removed and only the gpio_device
persist. The base and ngpio are such things, for example we
don't want a new chip arriving to overlap the number space
of a dangling gpio_device, and the chardev may still query
the device for the number of lines etc.
Note that the code that assigns base and insert gpio_device
into the global list no longer check for a missing gpio_chip:
we respect the number space allocated by any other gpio_device.
As a consequence of the gdev being referenced directly from
the gpio_desc, we need to verify it differently from all
in-kernel API calls that fall through to direct queries to
the gpio_chip vtable: we first check that desc is !NULL, then
that desc->gdev is !NULL, then, if desc->gdev->chip is NULL,
we *BAIL OUT* without any error, so as to manage the case
where operations are requested on a device that is gone.
These checks were non-uniform and partly missing in the past:
so to simplify: create the macros VALIDATE_DESC() that will
return -EINVAL if the desc or desc->gdev is missing and just
0 if the chip is gone, and conversely VALIDATE_DESC_VOID()
for the case where the function does not return an error.
By using these macros, we get warning messages about missing
gdev with reference to the right function in the kernel log.
Despite the macro business this simplifies the code and make
it more readable than if we copy/paste the same descriptor
checking code into all code ABI call sites (IMHO).
Linus Walleij [Thu, 11 Feb 2016 19:16:45 +0000 (20:16 +0100)]
gpio/pinctrl: sunxi: stop poking around in private vars
This kind of hacks disturbs the refactoring of the gpiolib.
The descriptor table belongs to the gpiolib, if we want to know
something about something in it, use or define the proper accessor
functions. Let's add this gpiochip_lins_is_irq() to do what the
sunxi driver is trying at so we can privatize the descriptors
properly.
Linus Walleij [Tue, 9 Feb 2016 12:51:59 +0000 (13:51 +0100)]
gpio: move descriptors into gpio_device
We need gpio_device to hold the descriptors so that they can
be lifecycled with the struct gpio_device held from userspace.
Move the descriptor array into gpio_device. Also rename it from
"desc" (singularis) to "descs" (pluralis) to reflect the fact
that it is an array.
Linus Walleij [Tue, 9 Feb 2016 12:21:06 +0000 (13:21 +0100)]
gpio: move sysfs mock device to the gpio_device
Since gpio_device is the struct that survives if the backing
gpio_chip is removed, move the sysfs mock device to this state
container so it becomes part of the dangling state of the
GPIO device on removal.
Linus Walleij [Tue, 9 Feb 2016 13:27:42 +0000 (14:27 +0100)]
gpio: remember to finally free gpio_device
When the device core reference count for the device goes to
0 and it calls .release() we free resources and so can also
finally free up the GPIO state container, struct gpio_device.
Driver for the GPIO block found in ti's tps65218 pmics.
The device has two GPIOs and one GPO pin which can be configured as follows:
GPIO1:
-general-purpose, open-drain output controlled by GPO1 user bit and/or
sequencer
-DDR3 reset input signal from SOC. Signal is either latched or
passed-trough to GPO2 pin. See below for details.
GPO2:
-general-purpose output controlled by GPO2 user bit
-DDR3 reset output signal. Signal is controlled by GPIO1 and PGOOD.
See below for details.
-Output buffer can be configured as open-drain or push-pull.
GPIO3:
-general-purpose, open-drain output controlled by GPO3 user bit and/or
sequencer
-reset input-signal for DCDC1 and DCDC2.
The input configurations are not meant to be used by the user so the driver
only offers GPOs.
v2: Added request routine that evaluates the fw config flags and removed module
owner
v3: Added .direction_input() routine, and took care of all Linus Walleij
suggestions (clamp to bool, use proper include)
Signed-off-by: Nicolas Saenz Julienne <nicolassaenzj@gmail.com> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This includes SPI compatible devices like SN74165 serial-out shift
registers and the SN65HVS88x series of industrial serializers that can
be read over the SPI bus and used for GPI (General Purpose Input).
Signed-off-by: Andrew F. Davis <afd@ti.com> Tested-by: Sean Nyekjaer <sean.nyekjaer@prevas.dk> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Alban Bedel [Thu, 28 Jan 2016 19:44:32 +0000 (20:44 +0100)]
gpio: ath79: Add support for the interrupt controller
Add support for the interrupt controller using GPIOLIB_IRQCHIP.
Both edges isn't supported by the chip and has to be emulated
by switching the polarity on each interrupt.
Signed-off-by: Alban Bedel <albeu@free.fr> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Alban Bedel [Thu, 28 Jan 2016 19:44:30 +0000 (20:44 +0100)]
gpio: ath79: Allow building in compile tests
To allow building the driver in compile tests we must drop the
dependency on asm/mach-ath79/ar71xx_regs.h. For this we replace the
include with local definition of the registers needed for this driver.
Signed-off-by: Alban Bedel <albeu@free.fr> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Alban Bedel [Thu, 28 Jan 2016 19:44:29 +0000 (20:44 +0100)]
gpio: ath79: Move to the generic GPIO driver
Drop most of the code in favor of the generic MMIO GPIO driver.
As the driver now depend on CONFIG_GPIO_GENERIC also add a Kconfig
entry to make the driver optional.
We leave the base pointer and lock in the data struct because they are
needed for the IRQ support.
Lokesh Vutla [Thu, 28 Jan 2016 13:38:51 +0000 (19:08 +0530)]
gpio: davinci: Fix the number of controllers allocated
Driver only needs to allocate for [ngpio / 32] controllers,
as each controller handles 32 gpios. But the current driver
allocates for ngpio of which the extra allocated are unused.
Fix it be registering only the required number of controllers.
Keerthy [Thu, 28 Jan 2016 13:38:50 +0000 (19:08 +0530)]
gpio: davinci: Add the missing of-node pointer
Currently the first parameter of irq_domain_add_legacy is NULL.
irq_find_host function returns NULL when we do not populate the of_node
and hence irq_of_parse_and_map call fails whenever we want to request a
gpio irq. This fixes the request_irq failures for gpio interrupts.
Linus Walleij [Wed, 21 Oct 2015 13:45:54 +0000 (15:45 +0200)]
tools/gpio: create GPIO tools
This creates GPIO tools under tools/gpio/* and adds a single
example program to list the GPIOs on a system. When proper
devices are created it provides this minimal output:
Cc: Johan Hovold <johan@kernel.org> Cc: Michael Welling <mwelling@ieee.org> Cc: Markus Pargmann <mpa@pengutronix.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Linus Walleij [Wed, 21 Oct 2015 13:29:53 +0000 (15:29 +0200)]
gpio: add a userspace chardev ABI for GPIOs
A new chardev that is to be used for userspace GPIO access is
added in this patch. It is intended to gradually replace the
horribly broken sysfs ABI.
Using a chardev has many upsides:
- All operations are per-gpiochip, which is the actual
device underlying the GPIOs, making us tie in to the
kernel device model properly.
- Hotpluggable GPIO controllers can come and go, as this
kind of problem has been know to userspace for character
devices since ages, and if a gpiochip handle is held in
userspace we know we will break something, whereas the
sysfs is stateless.
- The one-value-per-file rule of sysfs is really hard to
maintain when you want to twist more than one knob at a time,
for example have in-kernel APIs to switch several GPIO
lines at the same time, and this will be possible to do
with a single ioctl() from userspace, saving a lot of
context switching.
We also need to add a new bus type for GPIO. This is
necessary for example for userspace coldplug, where sysfs is
traversed to find the boot-time device nodes and create the
character devices in /dev.
This new chardev ABI is *non* *optional* and can be counted
on to be present in the future, emphasizing the preference
of this ABI.
The ABI only implements one single ioctl() to get the name
and number of GPIO lines of a chip. Even this is debatable:
see it as a minimal example for review. This ABI shall be
ruthlessly reviewed and etched in stone.
The old /sys/class/gpio is still optional to compile in,
but will be deprecated.
Unique device IDs are created using IDR, which is overkill
and insanely scalable, but also well tested.
Cc: Johan Hovold <johan@kernel.org> Cc: Michael Welling <mwelling@ieee.org> Cc: Markus Pargmann <mpa@pengutronix.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Linus Walleij [Tue, 20 Oct 2015 09:10:38 +0000 (11:10 +0200)]
gpio: make the gpiochip a real device
GPIO chips have been around for years, but were never real devices,
instead they were piggy-backing on a parent device (such as a
platform_device or amba_device) but this was always optional.
GPIO chips could also exist without any device at all, with its
struct device *parent (ex *dev) pointer being set to null.
When sysfs was in use, a mock device would be created, with the
optional parent assigned, or just floating orphaned with NULL
as parent.
If sysfs is active, it will use this device as parent.
We now create a gpio_device struct containing a real
struct device and move the subsystem over to using that. The
list of struct gpio_chip:s is augmented to hold struct
gpio_device:s and we find gpio_chips:s by first looking up
the struct gpio_device.
The struct gpio_device is designed to stay around even if the
gpio_chip is removed, so as to satisfy users in userspace
that need a backing data structure to hold the state of the
session initiated with e.g. a character device even if there is
no physical chip anymore.
From this point on, gpiochips are devices.
Cc: Johan Hovold <johan@kernel.org> Cc: Michael Welling <mwelling@ieee.org> Cc: Markus Pargmann <mpa@pengutronix.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
projects / linux-beck.git / log