gpiod_get/set functions share common code between their regular and
cansleep variants. The exporting of the gpiod interface will make
the situation worse. This patch factorizes the common code to avoid code
redundancy.
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Provide the human readable label for the GPIO as well as the number when
we are recording it in order to improve the readability of log messages.
Signed-off-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Currently many but not all GPIO log messages log the GPIO number and the
formats vary. Ensure that this is done consistently by defining logging
helpers which take the GPIO descriptor.
The will help people pattern matching on logs and providing the number
makes the log messages that omitted it more useful.
Signed-off-by: Mark Brown <broonie@linaro.org>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
It appears some drivers are using gpio_set_debounce()
opportunistically, i.e. without knowing whether it works or
not. (Example: input/keyboard/gpio_keys.c) to account for
this use case, return -ENOTSUPP and do not print any
warnings in this case.
Took a round over the other gpio_set_debounce() consumers
to make sure that none of them are relying on the returned
error code to be something specific.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
At several places the gpiolib will proceed to handle a GPIO
descriptor even if it's ->chip member is NULL and no gpiochip
is associated.
Fix this by checking that both the descriptor cookie *and*
the chip pointer are valid.
Also bail out earlier with more specific diagnostic messages
on missing operations for setting as input/output or debounce.
ChangeLog v1->v2:
- Also return -EIO on gpiod_set_debounce() with missing
operations in the vtable
- Fix indentations.
Suggested-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Frank Rowand <frank.rowand@sonymobile.com>
Cc: Tim Bird <tim.bird@sonymobile.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The usage of strict_strtol() is not preferred, because
strict_strtol() is obsolete. Thus, kstrtol() should be
used.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This comment applies to gpio_to_chip(), not gpiod_to_chip().
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Constify descriptor parameter of gpiod_* functions for those that
should obviously not modify it. This includes value or direction get,
cansleep, and IRQ number query.
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Some functions dereferenced their GPIO descriptor argument without
checking its validity first, potentially leading to an oops when given
an invalid argument.
This patch also makes gpio_get_value() more resilient when given an
invalid GPIO, returning 0 instead of silently crashing.
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Cc: Ryan Mallon <rmallon@gmail.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Convert to the much saner new idr interface.
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This branch contains the usual set of individual driver improvements and
bug fixes, as well as updates to the core code. The more notable changes
include:
- Internally add new API for referencing GPIOs by gpio_desc instead of
number. Eventually this will become a public API
- ACPI GPIO binding support
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Merge tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux
Pull GPIO changes from Grant Likely:
"This branch contains the usual set of individual driver improvements
and bug fixes, as well as updates to the core code. The more notable
changes include:
- Internally add new API for referencing GPIOs by gpio_desc instead
of number. Eventually this will become a public API
- ACPI GPIO binding support"
* tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux: (33 commits)
arm64: select ARCH_WANT_OPTIONAL_GPIOLIB
gpio: em: Use irq_domain_add_simple() to fix runtime error
gpio: using common order: let 'static const' instead of 'const static'
gpio/vt8500: memory cleanup missing
gpiolib: Fix locking on gpio debugfs files
gpiolib: let gpio_chip reference its descriptors
gpiolib: use descriptors internally
gpiolib: use gpio_chips list in gpiochip_find_base
gpiolib: use gpio_chips list in sysfs ops
gpiolib: use gpio_chips list in gpiochip_find
gpiolib: use gpio_chips list in gpiolib_sysfs_init
gpiolib: link all gpio_chips using a list
gpio/langwell: cleanup driver
gpio/langwell: Add Cloverview ids to pci device table
gpio/lynxpoint: add chipset gpio driver.
gpiolib: add missing braces in gpio_direction_show
gpiolib-acpi: Fix error checks in interrupt requesting
gpio: mpc8xxx: don't set IRQ_TYPE_NONE when creating irq mapping
gpiolib: remove gpiochip_reserve()
arm: pxa: tosa: do not use gpiochip_reserve()
...
The debugfs files really need to hold the gpiolib spinlock before
accessing the list. Otherwise chip addition/removal will cause an oops.
Cc: Alexandre Courbot <acourbot@nvidia.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Add a pointer to the gpio_chip structure that references the array of
GPIO descriptors belonging to the chip, and update gpiolib code to use
this pointer instead of the global gpio_desc[] array. This is another
step towards the removal of the gpio_desc[] global array.
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.orh>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Make sure gpiolib works internally with descriptors and (chip, offset)
pairs instead of using the global integer namespace. This prepares the
ground for the removal of the global gpio_desc[] array and the
introduction of the descriptor-based GPIO API.
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
[grant.likely: Squash in fix for link error when CONFIG_SYSFS=n]
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Re-implement gpiochip_find_base using the list of chips instead of the
global gpio_desc[] array. This makes it both simpler and more efficient,
and is needed to remove the global descriptors array.
The new code should preserve the exact same GPIO number assignment
policy as the code it is replacing. There shouldn't be any visible
change to the assigned GPIO numbers.
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
[grant.likely: Added comment about assignment policy]
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This makes the code both simpler and faster compared to parsing the GPIO
number space.
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Using the GPIO chips list is much faster than parsing the entire GPIO
number space.
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Use the small list of GPIO chips instead of parsing the whole GPIO
number space.
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Add a list member to gpio_chip that allows all chips to be parsed
quickly. The current method requires parsing the entire GPIO integer
space, which is painfully slow. Using a list makes many chip operations
that involve lookup or parsing faster, and also simplifies the code. It
is also necessary to eventually get rid of the global gpio_desc[] array.
The list of gpio_chips is always ordered by base GPIO number to ensure
chips traversal is done in the right order.
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
All in-kernel users of class_find_device() don't really need mutable
data for match callback.
In two places (kernel/power/suspend_test.c, drivers/scsi/osd/osd_uld.c)
this patch changes match callbacks to use const search data.
The const is propagated to rtc_class_open() and power_supply_get_by_name()
parameters.
Note that there's a dev reference leak in suspend_test.c that's not
touched in this patch.
Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
gpiochip_reserve() has no user and stands in the way of the removal of
the static gpio_desc[] array. Remove this function as well as the now
unneeded RESERVED flag of struct gpio_desc.
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Primarily device driver additions, features and bug fixes. Not much
touching gpio common subsystem support. Should not be scary.
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Merge tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux-2.6
Pull GPIO updates from Grant Likely:
"GPIO follow up patch and type change for v3.5 merge window
Primarily device driver additions, features and bug fixes. Not much
touching gpio common subsystem support. Should not be scary."
* tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux-2.6: (34 commits)
gpio: Provide the STMPE GPIO driver with its own IRQ Domain
gpio: add TS-5500 DIO blocks support
gpio: pcf857x: use client->irq for gpio_to_irq()
gpio: stmpe: Add DT support for stmpe gpio
gpio: pl061 depends on ARM
gpio/pl061: remove old comment
gpio: SPEAr: add spi chipselect control driver
gpio: gpio-max710x: Support device tree probing
gpio: twl4030: Use only TWL4030_MODULE_LED for LED configuration
gpio: tegra: read output value when gpio is set in direction_out
gpio: pca953x: Add compatible strings to gpio-pca953x driver
gpio: pca953x: Register an IRQ domain
gpio: mvebu: Set free callback for gpio_chip
gpio: tegra: Drop exporting static functions
gpio: tegra: Staticize non-exported symbols
gpio: tegra: fix suspend/resume apis
gpio-pch: Set parent dev for gpio chip
gpio: em: Fix build errors
GPIO: clps711x: use platform_device_unregister in gpio_clps711x_init()
gpio/tc3589x: convert to use the simple irqdomain
...
This is introduced by commit 9ab6e988
"gpiolib: return any error code from range creation".
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
To be crystal clear on what the arguments mean in this
funtion dealing with both GPIO and PIN ranges with confusing
naming, we now have gpio_offset and pin_offset and we are
on the clear that these are offsets into the specific GPIO
and pin controller respectively. The GPIO chip itself will
of course keep track of the base offset into the global
GPIO number space.
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
If we try to create a range for a certain GPIO chip and the
target pin controller is not yet available it may return
a probe deferral error code, so handle this all the way
our by checking the error code.
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Rename the function find_pinctrl_and_add_gpio_range()
to pinctrl_find_and_add_gpio_range() so as to be consistent
with the rest of the functions.
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Like with commit 3c739ad0df
it is not always enough to specify all the pins of a gpio_chip
from offset zero to be added to a pin map range, since the
mapping from GPIO to pin controller may not be linear at all,
but need to be broken into a few consecutive sub-ranges or
1-pin entries for complicated cases. The ranges may also be
sparse.
This alters the signature of the function to accept offsets
into both the GPIO-chip local pinspace and the pin controller
local pinspace.
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The fact that of_gpiochip_add_pin_range() and
gpiochip_add_pin_range() share too much code is fragile and
will invariably mean that bugs need to be fixed in two places
instead of one.
So separate the concerns of gpiolib.c and gpiolib-of.c and
have the latter call the former as back-end. This is necessary
also when going forward with other device descriptions such
as ACPI.
This is done by:
- Adding a return code to gpiochip_add_pin_range() so we can
reliably check whether this succeeds.
- Get rid of the custom of_pinctrl_add_gpio_range() from
pinctrl. Instead create of_pinctrl_get() to just retrive the
pin controller per se from an OF node. This composite
function was just begging to be deleted, it was way to
purpose-specific.
- Use pinctrl_dev_get_name() to get the name of the retrieved
pin controller and use that to call back into the generic
gpiochip_add_pin_range().
Now the pin range is only allocated and tied to a pin
controller from the core implementation in gpiolib.c.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This makes us call gpiochio_remove_pin_ranges() in the
gpiochip_remove() function, so we get rid of ranges when
freeing the chip.
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Commit 69e1601bca88809dc118abd1becb02c15a02ec71
"gpiolib: provide provision to register pin ranges"
Got most of it's function prototypes wrong, so fix this up by:
- Moving the void declarations into static inlines in
<linux/gpio.h> (previously the actual prototypes were declared
here...)
- Declare the gpiochip_add_pin_range() and
gpiochip_remove_pin_ranges() functions in <asm-generic/gpio.h>
together with the pin range struct declaration itself.
- Actually only implement these very functions in gpiolib.c
if CONFIG_PINCTRL is set.
- Additionally export the symbols since modules will need to
be able to do this.
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
pinctrl subsystem needs gpio chip base to prepare set of gpio
pin ranges, which a given pinctrl driver can handle. This is
important to handle pinctrl gpio request calls in order to
program a given pin properly for gpio operation.
As gpio base is allocated dynamically during gpiochip
registration, presently there exists no clean way to pass this
information to the pinctrl subsystem.
After few discussions from [1], it was concluded that may be
gpio controller reporting the pin range it supports, is a
better way than pinctrl subsystem directly registering it.
[1] http://comments.gmane.org/gmane.linux.ports.arm.kernel/184816
Cc: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Shiraz Hashim <shiraz.hashim@st.com>
[Edited documentation a bit]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
We need to unlock here before returning.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
gpios requested with invalid numbers, or gpios requested from userspace via sysfs
should not try to be deferred on failure.
Cc: stable@kernel.org
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Add .get_direction callback to gpio_chip. This allows gpiolib
to check the current direction of a gpio.
Used to show the correct gpio direction in sysfs and debug entries.
If callback is not set then gpiolib will work as previously;
e.g. guessing everything is input until a direction is set.
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
The gpio_export function uses nested if statements and the status
variable to handle the failure cases. This makes the function logic
difficult to follow. Refactor the code to abort immediately on failure
using goto. This makes the code slightly longer, but significantly
reduces the nesting and number of split lines and makes the code easier
to read.
Signed-off-by: Ryan Mallon <rmallon@gmail.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
When dumping a collection of items via seq_file, it is recommended to
use the iterator interface. For the gpiolib debugfs interface this can
be done to dump each GPIO chip in turn.
Note that for gpiolib this is a little cumbersome because it does not
provide a list of registered GPIO chips and the only way to iterate is
over each GPIO individually. Once a chip is found, the number of GPIOs
it provides can be skipped as a small optimization.
This patch was requested by Arnd Bergmann here:
http://article.gmane.org/gmane.linux.ports.tegra/3535
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
Cc: Linus Walleij <linus.walleij@stericsson.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Since users must be explicitly provided with a GPIO number in order to
request one the overwhelmingly common case for failing to request will
be that the required GPIO driver has not yet registered and we should
therefore defer until it has registered.
In order to avoid having to code this logic in individual drivers have
gpio_request() return -EPROBE_DEFER when failing to look up the GPIO.
Drivers which don't want this behaviour can override it if they desire.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Commit 3d0f7cf0 "gpio: Adjust of_xlate API to support multiple GPIO
chips" changed the api of gpiochip_find to drop const from the data
parameter of the match hook, but didn't also drop const from data
causing a build warning.
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
The pr_info message in gpiochip_add gets displayed for every
gpiochip registered. When first bringing up a system this
information could be helpful but for normal use it's just a
bunch of noise. Change the message to a pr_debug.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This patch changes the of_xlate API to make it possible for multiple
gpio_chips to refer to the same device tree node. This is useful for
banked GPIO controllers that use multiple gpio_chips for a single
device. With this change the core code will try calling of_xlate on
each gpio_chip that references the device_node and will return the
gpio number for the first one to return 'true'.
Tested-by: Roland Stigge <stigge@antcom.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Introduce new flags to automatically export GPIOs when using the convenience
functions gpio_request_one() or gpio_request_array(). This eases support for
custom boards where lots of GPIOs need to be exported for customer
applications.
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
I've seen users getting very confused by the WARN_ON()s for can_sleep
GPIOs in the atomic-safe paths, the discoverability of the non-atomic
version of the API seems to be hampered by the fact that it's defined
in a header file not the .c file where the warnings are.
Add a couple of comments next to the warnings to help people on their
way.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Reviwed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Adding support for the open source gpio on which client
can specify the open source property through GPIO flag
GPIOF_OPEN_SOURCE at the time of gpio request.
The open source pins are normally pulled low and it
cannot be driven to output with value of 0 and so
when client request for setting the pin to LOW, the
gpio will be set to input direction to make pin in tristate
and hence PULL-DOWN on pins will make the state to LOW.
The open source pin can be driven to HIGH by setting output
with value of 1.
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviwed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Adding support for the open drain gpio on which client
can specify the open drain property through GPIO flag
GPIOF_OPEN_DRAIN at the time of gpio request.
The open drain pins are normally pulled high and it
cannot be driven to output with value of 1 and so
when client request for setting the pin to HIGH, the
gpio will be set to input direction to make pin in tristate
and hence PULL-UP on pins will make the state to HIGH.
The open drain pin can be driven to LOW by setting output
with value of 0.
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviwed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
A large chunk of qe_pin_request() is unnecessarily cut-and-paste
directly from of_get_named_gpio_flags(). This patch cuts out the
duplicate code and replaces it with a call to of_get_gpio().
v2: fixed compile error due to missing gpio_to_chip()
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Kumar Gala <galak@kernel.crashing.org>
This patch adds a kernel message, containing GPIO range and device
name on successful device registration, and removes duplicate messages from the following drivers:
* gpio-adp5588
* gpio-bt8xx
* gpio-cs5535
* gpio-janz-ttl
* gpio-nomadik
* gpio-pcf857x
* gpio-xilinx
* drivers/of/gpio.c
Signed-off-by: Hartmut Knaack <knaack.h@gmx.de>
[grant.likely@secretlab.ca: squashed 2 patches together]
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
