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path: root/drivers/gpio/gpiolib.c
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2011-12-12gpio/powerpc: Eliminate duplication of of_get_named_gpio_flags()Grant Likely
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>
2011-12-12gpiolib: output basic details and consolidate gpio device driversGrant Likely
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>
2011-05-27gpio: make gpio_{request,free}_array gpio array parameter constLars-Peter Clausen
gpio_{request,free}_array should not (and do not) modify the passed gpio array, so make the parameter const. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Eric Miao <eric.y.miao@gmail.com> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-05-20gpio: add trace events for setting direction and valueUwe Kleine-König
This patch allows to trace gpio operations using ftrace Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-05-20gpiolib: export gpiochip_findJean Delvare
Export function gpiochip_find so that modules can use it. Signed-off-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-03-25arm/gpio: Remove three copies of broken and racy debug codeThomas Gleixner
gpiolib plus two gpio implementations in arm fiddle in the guts of irq_desc in a racy and buggy way. Remove the stuff. I already told the gpio folks that we can provide that information in a proper way if necessary. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Grant Likely <grant.likely@secretlab.ca> LKML-Reference: <20110324212508.931638262@linutronix.de>
2010-12-22gpiolib: gpio_request_one(): add missing gpio_free()Aaro Koskinen
If GPIO request succeeds, but configuration fails, it should be released. Signed-off-by: Aaro Koskinen <aaro.koskinen@nokia.com> Acked-by: Eric Miao <eric.miao@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-11gpiolib: allow nested threaded irqs for poll(2)Daniel Gl?ckner
The pca953x driver requires the use of threaded irqs as its irq demultiplexer can sleep. Our irq handler can be called from any context, so use request_any_context_irq to allow threaded irqs as well. Signed-off-by: Daniel Gl?ckner <dg@emlix.com> Reported-by: Ian Jeffray <ian@jeffray.co.uk> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-11gpiolib: get rid of struct poll_desc and workletDaniel Gl?ckner
As sysfs_notify_dirent has been made irq safe, there is no reason to not call it directly from irq. With the work_struct removed, the remaining element in poll_desc is a sysfs_dirent pointer which may not be NULL. We can therefore store it directly in the idr and pass it as context to the irq handler. Most part of the patch deals with renaming defines and variables to reflect their new use without functional change. I also took the opportunity to initialize the idr statically. Signed-off-by: Daniel Gl?ckner <dg@emlix.com> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-11gpiolib: decouple might_sleep_if() from DEBUGDavid Brownell
Be more consistent about runtime programming interface abuse warnings, which can reduce some confusion and trigger bugfixes. Based on an observation and patch from Jani Nikula. Also update doc to highlight some sleeping-call issues and to match some recent changes. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Jani Nikula <ext-jani.1.nikula@nokia.com> Cc: "Ryan Mallon" <ryan@bluewatersys.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-08-05Merge branch 'next-devicetree' of git://git.secretlab.ca/git/linux-2.6Linus Torvalds
* 'next-devicetree' of git://git.secretlab.ca/git/linux-2.6: (63 commits) of/platform: Register of_platform_drivers with an "of:" prefix of/address: Clean up function declarations of/spi: call of_register_spi_devices() from spi core code of: Provide default of_node_to_nid() implementation. of/device: Make of_device_make_bus_id() usable by other code. of/irq: Fix endian issues in parsing interrupt specifiers of: Fix phandle endian issues of/flattree: fix of_flat_dt_is_compatible() to match the full compatible string of: remove of_default_bus_ids of: make of_find_device_by_node generic microblaze: remove references to of_device and to_of_device sparc: remove references to of_device and to_of_device powerpc: remove references to of_device and to_of_device of/device: Replace of_device with platform_device in includes and core code of/device: Protect against binding of_platform_drivers to non-OF devices of: remove asm/of_device.h of: remove asm/of_platform.h of/platform: remove all of_bus_type and of_platform_bus_type references of: Merge of_platform_bus_type with platform_bus_type drivercore/of: Add OF style matching to platform bus ... Fix up trivial conflicts in arch/microblaze/kernel/Makefile due to just some obj-y removals by the devicetree branch, while the microblaze updates added a new file.
2010-07-27gpio: fix spurious printk when freeing a gpioJon Povey
When freeing a gpio that has not been exported, gpio_unexport() prints a debug message when it should just fall through silently. Example spurious message: gpio_unexport: gpio0 status -22 Signed-off-by: Jon Povey <jon.povey@racelogic.co.uk> Cc: David Brownell <david-b@pacbell.net> Acked-by: Uwe Kleine-K?nig <u.kleine-koenig@pengutronix.de> Cc: Gregory Bean <gbean@codeaurora.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-07-05of/gpio: add default of_xlate function if device has a node pointerAnton Vorontsov
Implement generic OF gpio hooks and thus make device-enabled GPIO chips (i.e. the ones that have gpio_chip->dev specified) automatically attach to the OpenFirmware subsystem. Which means that now we can handle I2C and SPI GPIO chips almost* transparently. * "Almost" because some chips still require platform data, and for these chips OF-glue is still needed, though with this change the glue will be much smaller. Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Cc: David Brownell <dbrownell@users.sourceforge.net> Cc: Bill Gatliff <bgat@billgatliff.com> Cc: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Jean Delvare <khali@linux-fr.org> Cc: Andrew Morton <akpm@linux-foundation.org> CC: linux-kernel@vger.kernel.org CC: devicetree-discuss@lists.ozlabs.org
2010-07-05of/gpio: stop using device_node data pointer to find gpio_chipGrant Likely
Currently the kernel uses the struct device_node.data pointer to resolve a struct gpio_chip pointer from a device tree node. However, the .data member doesn't provide any type checking and there aren't any rules enforced on what it should be used for. There's no guarantee that the data stored in it actually points to an gpio_chip pointer. Instead of relying on the .data pointer, this patch modifies the code to add a lookup function which scans through the registered gpio_chips and returns the gpio_chip that has a pointer to the specified device_node. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> CC: Andrew Morton <akpm@linux-foundation.org> CC: Anton Vorontsov <avorontsov@ru.mvista.com> CC: Grant Likely <grant.likely@secretlab.ca> CC: David Brownell <dbrownell@users.sourceforge.net> CC: Bill Gatliff <bgat@billgatliff.com> CC: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com> CC: Benjamin Herrenschmidt <benh@kernel.crashing.org> CC: Jean Delvare <khali@linux-fr.org> CC: linux-kernel@vger.kernel.org CC: devicetree-discuss@lists.ozlabs.org
2010-07-05gpiolib: cosmetic improvements for error handling in gpiochip_add()Anton Vorontsov
Hopefully it makes the code look nicer and makes it easier to extend this function. Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Grant Likely <grant.likely@secretlab.ca> CC: devicetree-discuss@lists.ozlabs.org CC: linux-kernel@vger.kernel.org
2010-05-27gpiolib: introduce set_debounce methodFelipe Balbi
A few architectures, like OMAP, allow you to set a debouncing time for the gpio before generating the IRQ. Teach gpiolib about that. Mark said: : This would be generally useful for embedded systems, especially where : the interrupt concerned is a wake source. It allows drivers to avoid : spurious interrupts from noisy sources so if the hardware supports it : the driver can avoid having to explicitly wait for the signal to become : stable and software has to cope with fewer events. We've lived without : it for quite some time, though. David said: : I looked at adding debounce support to the generic GPIO calls (and thus : gpiolib) some time back, but decided against it. I forget why at this : time (check list archives) but it wasn't because of lack of utility in : certain contexts. : : One thing to watch out for is just how variable the hardware capabilities : are. Atmel GPIOs have something like a fixed number of 32K clock cycles : for debounce, twl4030 had something odd, OMAPs were more like the Atmel : chips but with a different clock. In some cases debouncing had to be : ganged, not per-GPIO. And so forth. Signed-off-by: Felipe Balbi <felipe.balbi@nokia.com> Cc: Tony Lindgren <tony@atomide.com> Cc: David Brownell <david-b@pacbell.net> Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27gpiolib: make gpiochip_add() show a better error messageBen Dooks
The current message, 'not registered' is confusing as it implies it was not registered with something, whereas printing 'failed to register' implies it was the gpiochip_add() call that did not work correctly. Signed-off-by: Ben Dooks <ben-linux@fluff.org> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27gpiolib: a gpio is unsigned, so use %u to print itUwe Kleine-König
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-27gpiolib: make names array and its values constUwe Kleine-König
gpiolib doesn't need to modify the names and I assume most initializers use string constants that shouldn't be modified anyhow. [akpm@linux-foundation.org: fix drivers/gpio/cs5535-gpio.c] Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Cc: Kevin Wells <kevin.wells@nxp.com> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-05-21sysfs: Implement sysfs tagged directory support.Eric W. Biederman
The problem. When implementing a network namespace I need to be able to have multiple network devices with the same name. Currently this is a problem for /sys/class/net/*, /sys/devices/virtual/net/*, and potentially a few other directories of the form /sys/ ... /net/*. What this patch does is to add an additional tag field to the sysfs dirent structure. For directories that should show different contents depending on the context such as /sys/class/net/, and /sys/devices/virtual/net/ this tag field is used to specify the context in which those directories should be visible. Effectively this is the same as creating multiple distinct directories with the same name but internally to sysfs the result is nicer. I am calling the concept of a single directory that looks like multiple directories all at the same path in the filesystem tagged directories. For the networking namespace the set of directories whose contents I need to filter with tags can depend on the presence or absence of hotplug hardware or which modules are currently loaded. Which means I need a simple race free way to setup those directories as tagged. To achieve a reace free design all tagged directories are created and managed by sysfs itself. Users of this interface: - define a type in the sysfs_tag_type enumeration. - call sysfs_register_ns_types with the type and it's operations - sysfs_exit_ns when an individual tag is no longer valid - Implement mount_ns() which returns the ns of the calling process so we can attach it to a sysfs superblock. - Implement ktype.namespace() which returns the ns of a syfs kobject. Everything else is left up to sysfs and the driver layer. For the network namespace mount_ns and namespace() are essentially one line functions, and look to remain that. Tags are currently represented a const void * pointers as that is both generic, prevides enough information for equality comparisons, and is trivial to create for current users, as it is just the existing namespace pointer. The work needed in sysfs is more extensive. At each directory or symlink creating I need to check if the directory it is being created in is a tagged directory and if so generate the appropriate tag to place on the sysfs_dirent. Likewise at each symlink or directory removal I need to check if the sysfs directory it is being removed from is a tagged directory and if so figure out which tag goes along with the name I am deleting. Currently only directories which hold kobjects, and symlinks are supported. There is not enough information in the current file attribute interfaces to give us anything to discriminate on which makes it useless, and there are no potential users which makes it an uninteresting problem to solve. Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Benjamin Thery <benjamin.thery@bull.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-04-28gpio: potential null dereferenceDan Carpenter
Smatch found a potential null dereference in gpio_setup_irq(). The "pdesc" variable is allocated with idr_find() that can return NULL. If gpio_setup_irq() is called with 0 as gpio_flags and "pdesc" is null, it would OOPs here. Signed-off-by: Dan Carpenter <error27@gmail.com> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-07driver-core: Add attribute argument to class_attribute show/storeAndi Kleen
Passing the attribute to the low level IO functions allows all kinds of cleanups, by sharing low level IO code without requiring an own function for every piece of data. Also drivers can extend the attributes with own data fields and use that in the low level function. This makes the class attributes the same as sysdev_class attributes and plain attributes. This will allow further cleanups in drivers. Full tree sweep converting all users. Signed-off-by: Andi Kleen <ak@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-03-06gpio: introduce gpio_request_one() and friendsEric Miao
gpio_request() without initial configuration of the GPIO is normally useless, introduce gpio_request_one() together with GPIOF_ flags for input/output direction and initial output level. gpio_{request,free}_array() for multiple GPIOs. Signed-off-by: Eric Miao <eric.y.miao@gmail.com> Cc: David Brownell <dbrownell@users.sourceforge.net> Cc: Ben Nizette <bn@niasdigital.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2010-01-11gpiolib: fix poll(2) support reconfigure on sysfs polarity changeJani Nikula
Previously enabled poll(2) support on one edge was never reconfigured when sysfs polarity change was triggered from kernel, because 'struct device *dev' shadowed an earlier definition. Found by sparse, which I should've run much earlier. Signed-off-by: Jani Nikula <ext-jani.1.nikula@nokia.com> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-12-16gpiolib: add support for changing value polarity in sysfsJani Nikula
Drivers may use gpiolib sysfs as part of their public user space interface. The GPIO number and polarity might change from board to board. The gpio_export_link() call can be used to hide the GPIO number from user space. Add support for also hiding the GPIO line polarity changes from user space. Signed-off-by: Jani Nikula <ext-jani.1.nikula@nokia.com> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-11-12gpiolib: fix device_create() result checkSergei Shtylyov
In case of failure, device_create() returns not NULL but the error code. The current code checks for non-NULL though which causes kernel oops in sysfs_create_group() when device_create() fails. Check for error using IS_ERR() and propagate the error value using PTR_ERR() instead of fixed -ENODEV code returned now... Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-10-01const: constify remaining file_operationsAlexey Dobriyan
[akpm@linux-foundation.org: fix KVM] Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Acked-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-23gpiolib: allow poll() on valueDaniel Glöckner
Many gpio chips allow to generate interrupts when the value of a pin changes. This patch gives usermode application the opportunity to make use of this feature by calling poll(2) on the /sys/class/gpio/gpioN/value sysfs file. The edge to trigger can be set in the edge file in the same directory. Possible values are "none", "rising", "falling", and "both". Using level triggers is not possible with current sysfs since nothing changes the GPIO value (and the IRQ keeps triggering). Edge triggering will "just work". Note that if there was an event between read() and poll(), the poll() returns immediately. Also note that this version only supports true GPIO interrupts. Some later patch might be able to synthesize this behavior by timer-driven polling; some systems seem to need that. [dbrownell@users.sourceforge.net: align ids to 16 bit ids; whitespace] Signed-off-by: Daniel Glöckner <dg@emlix.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-09-23gpiolib: allow exported GPIO nodes to be named using sysfs linksJani Nikula
Commit 926b663ce8215ba448960e1ff6e58b67a2c3b99b (gpiolib: allow GPIOs to be named) already provides naming on the chip level. This patch provides more flexibility by allowing multiple names where ever in sysfs on a per GPIO basis. Adapted from David Brownell's comments on a similar concept: http://lkml.org/lkml/2009/4/20/203. [randy.dunlap@oracle.com: fix build for CONFIG_GENERIC_GPIO=n] Signed-off-by: Jani Nikula <ext-jani.1.nikula@nokia.com> Acked-by: David Brownell <david-b@pacbell.net> Cc: Daniel Silverstone <dsilvers@simtec.co.uk> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-02gpio: gpio_{request,free}() now required (feature removal)David Brownell
We want to phase out the GPIO "autorequest" mechanism in gpiolib and require all callers to use gpio_request(). - Update feature-removal-schedule - Update the documentation now - Convert the relevant pr_warning() in gpiolib to a WARN() so folk using this mechanism get a noisy stack dump Some drivers and board init code will probably need to change. Implementations not using gpiolib will still be fine; they are already required to implement gpio_{request,free}() stubs. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-02gpiolib: allow GPIOs to be namedDaniel Silverstone
Allow GPIOs in GPIOLIB chips to be named. This name is then used when the GPIO is exported to sysfs, although it could be used elsewhere if deemed useful. Signed-off-by: Daniel Silverstone <dsilvers@simtec.co.uk> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-29gpiolib: fix request related issueMagnus Damm
Fix request-already-requested handling in gpio_request(). Signed-off-by: Magnus Damm <damm@igel.co.jp> Acked-by: David Brownell <dbrownell@users.sourceforge.net> Cc: <stable@kernel.org> [2.6.28.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-06gpio: struct device - replace bus_id with dev_name(), dev_set_name()Kay Sievers
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2008-11-19gpiolib: extend gpio label column width in debugfs fileJarkko Nikula
There are already various drivers having bigger label than 12 bytes. Most of them fit well under 20 bytes but make column width exact so that oversized labels don't mess up output alignment. Signed-off-by: Jarkko Nikula <jarkko.nikula@nokia.com> Acked-by: David Brownell <david-b@pacbell.net> Cc: <stable@kernel.org> [2.6.26.x, 2.6.26.x, 2.6.27.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20Merge branch 'genirq-v28-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip This merges branches irq/genirq, irq/sparseirq-v4, timers/hpet-percpu and x86/uv. The sparseirq branch is just preliminary groundwork: no sparse IRQs are actually implemented by this tree anymore - just the new APIs are added while keeping the old way intact as well (the new APIs map 1:1 to irq_desc[]). The 'real' sparse IRQ support will then be a relatively small patch ontop of this - with a v2.6.29 merge target. * 'genirq-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (178 commits) genirq: improve include files intr_remapping: fix typo io_apic: make irq_mis_count available on 64-bit too genirq: fix name space collisions of nr_irqs in arch/* genirq: fix name space collision of nr_irqs in autoprobe.c genirq: use iterators for irq_desc loops proc: fixup irq iterator genirq: add reverse iterator for irq_desc x86: move ack_bad_irq() to irq.c x86: unify show_interrupts() and proc helpers x86: cleanup show_interrupts genirq: cleanup the sparseirq modifications genirq: remove artifacts from sparseirq removal genirq: revert dynarray genirq: remove irq_to_desc_alloc genirq: remove sparse irq code genirq: use inline function for irq_to_desc genirq: consolidate nr_irqs and for_each_irq_desc() x86: remove sparse irq from Kconfig genirq: define nr_irqs for architectures with GENERIC_HARDIRQS=n ...
2008-10-20gpiolib: fix oops in gpio_get_value_cansleep()David Brownell
We can get the following oops from gpio_get_value_cansleep() when a GPIO controller doesn't provide a get() callback: Unable to handle kernel paging request for instruction fetch Faulting instruction address: 0x00000000 Oops: Kernel access of bad area, sig: 11 [#1] [...] NIP [00000000] 0x0 LR [c0182fb0] gpio_get_value_cansleep+0x40/0x50 Call Trace: [c7b79e80] [c0183f28] gpio_value_show+0x5c/0x94 [c7b79ea0] [c01a584c] dev_attr_show+0x30/0x7c [c7b79eb0] [c00d6b48] fill_read_buffer+0x68/0xe0 [c7b79ed0] [c00d6c54] sysfs_read_file+0x94/0xbc [c7b79ef0] [c008f24c] vfs_read+0xb4/0x16c [c7b79f10] [c008f580] sys_read+0x4c/0x90 [c7b79f40] [c0013a14] ret_from_syscall+0x0/0x38 It's OK to request the value of *any* GPIO; most GPIOs are bidirectional, so configuring them as outputs just enables an output driver and doesn't disable the input logic. So the problem is that gpio_get_value_cansleep() isn't making the same sanity check that gpio_get_value() does: making sure this GPIO isn't one of the atypical "no input logic" cases. Reported-by: Anton Vorontsov <avorontsov@ru.mvista.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: <stable@kernel.org> [2.6.27.x, 2.6.26.x, 2.6.25.x] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-20gpio: modify sysfs gpio export so that "value" displays as 0 or 1Steven A. Falco
gpiolib can export GPIOs to userspace via sysfs. This patch modifies the gpio_value_show() so that any non-zero value is explicitly printed as "1", rather than whatever numerical value the lower-level driver returns. Signed-off-by: Steve Falco <sfalco@harris.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16gpiolib: request/free hooksDavid Brownell
Add a new internal mechanism to gpiolib to support low power operations by letting gpio_chip instances see when their GPIOs are in use. When no GPIOs are active, chips may be able to enter lower powered runtime states by disabling clocks and/or power domains. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: "Magnus Damm" <magnus.damm@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16gpiolib: gpio_to_irq() hooksDavid Brownell
Add a new gpiolib mechanism: gpio_chip instances can provide mappings between their (input) GPIOs and any associated IRQs. This makes it easier for platforms to support IRQs that are provided by board-specific external chips instead of as part of their core (such as SOC-integrated GPIOs). Also update the irq_to_gpio() description, saying to avoid it because it's not always supported. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16gpio_free might sleep, generic partUwe Kleine-König
According to the documentation gpio_free should only be called from task context only. To make this more explicit add a might sleep to all implementations. This is the generic part which changes gpiolib and the fallback implementation only. Signed-off-by: Uwe Kleine-König <ukleinek@informatik.uni-freiburg.de> Cc: David Brownell <david-b@pacbell.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16generic: sparse irqs: use irq_desc() together with dyn_array, instead of ↵Yinghai Lu
irq_desc[] add CONFIG_HAVE_SPARSE_IRQ to for use condensed array. Get rid of irq_desc[] array assumptions. Preallocate 32 irq_desc, and irq_desc() will try to get more. ( No change in functionality is expected anywhere, except the odd build failure where we missed a code site or where a crossing commit itroduces new irq_desc[] usage. ) v2: according to Eric, change get_irq_desc() to irq_desc() Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2008-07-25gpio: sysfs interfaceDavid Brownell
This adds a simple sysfs interface for GPIOs. /sys/class/gpio /export ... asks the kernel to export a GPIO to userspace /unexport ... to return a GPIO to the kernel /gpioN ... for each exported GPIO #N /value ... always readable, writes fail for input GPIOs /direction ... r/w as: in, out (default low); write high, low /gpiochipN ... for each gpiochip; #N is its first GPIO /base ... (r/o) same as N /label ... (r/o) descriptive, not necessarily unique /ngpio ... (r/o) number of GPIOs; numbered N .. N+(ngpio - 1) GPIOs claimed by kernel code may be exported by its owner using a new gpio_export() call, which should be most useful for driver debugging. Such exports may optionally be done without a "direction" attribute. Userspace may ask to take over a GPIO by writing to a sysfs control file, helping to cope with incomplete board support or other "one-off" requirements that don't merit full kernel support: echo 23 > /sys/class/gpio/export ... will gpio_request(23, "sysfs") and gpio_export(23); use /sys/class/gpio/gpio-23/direction to (re)configure it, when that GPIO can be used as both input and output. echo 23 > /sys/class/gpio/unexport ... will gpio_free(23), when it was exported as above The extra D-space footprint is a few hundred bytes, except for the sysfs resources associated with each exported GPIO. The additional I-space footprint is about two thirds of the current size of gpiolib (!). Since no /dev node creation is involved, no "udev" support is needed. Related changes: * This adds a device pointer to "struct gpio_chip". When GPIO providers initialize that, sysfs gpio class devices become children of that device instead of being "virtual" devices. * The (few) gpio_chip providers which have such a device node have been updated. * Some gpio_chip drivers also needed to update their module "owner" field ... for which missing kerneldoc was added. * Some gpio_chips don't support input GPIOs. Those GPIOs are now flagged appropriately when the chip is registered. Based on previous patches, and discussion both on and off LKML. A Documentation/ABI/testing/sysfs-gpio update is ready to submit once this merges to mainline. [akpm@linux-foundation.org: a few maintenance build fixes] Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Guennadi Liakhovetski <g.liakhovetski@pengutronix.de> Cc: Greg KH <greg@kroah.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-05-24gpiolib: fix off by one errorsTrent Piepho
The last gpio belonging to a chip is chip->base + chip->ngpios - 1. Some places in the code, but not all, forgot the critical minus one. Signed-off-by: Trent Piepho <xyzzy@speakeasy.org> Acked-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-30drivers: replace remaining __FUNCTION__ occurrencesHarvey Harrison
__FUNCTION__ is gcc-specific, use __func__ Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com> Cc: Ben Dooks <ben-linux@fluff.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28gpiochip_reserve()Anton Vorontsov
Add a new function gpiochip_reserve() to reserve ranges of gpios that platform code has pre-allocated. That is, this marks gpio numbers which will be claimed by drivers that haven't yet been loaded, and thus are not available for dynamic gpio number allocation. [akpm@linux-foundation.org: remove unneeded __must_check] [david-b@pacbell.net: don't export gpiochip_reserve (section fix)] Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28gpiolib: dynamic gpio number allocationAnton Vorontsov
If gpio_chip->base is negative during registration, gpiolib performs dynamic base allocation. This is useful for devices that aren't always present, such as GPIOs on hotplugged devices rather than mainboards. (This behavior was previously specified but not implemented.) To avoid using any numbers that may have been explicitly assigned but not yet registered, this dynamic allocation assigns GPIO numbers from the biggest number on down, instead of from the smallest on up. Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28gpio: define gpio_is_valid()Guennadi Liakhovetski
Introduce a gpio_is_valid() predicate; use it in gpiolib. Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@pengutronix.de> [ use inline function; follow the gpio_* naming convention; work without gpiolib; all programming interfaces need docs ] Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-28gpiolib: better rmmod infrastructureGuennadi Liakhovetski
As long as one or more GPIOs on a gpio chip are used its driver should not be unloaded. The existing mechanism (gpiochip_remove failure) doesn't address that, since rmmod can no longer be made to fail by having the cleanup code report errors. Module usecounts are the solution. Assuming standard "initialize struct to zero" policies, this change won't affect SOC platform drivers. However, drivers for external chips (on I2C and SPI busses) should be updated if they can be built as modules. Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@pengutronix.de> [ gpio_ensure_requested() needs to update module usecounts too ] Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05gpiolib: add gpio provider infrastructureDavid Brownell
Provide new implementation infrastructure that platforms may choose to use when implementing the GPIO programming interface. Platforms can update their GPIO support to use this. In many cases the incremental cost to access a non-inlined GPIO should be less than a dozen instructions, with the memory cost being about a page (total) of extra data and code. The upside is: * Providing two features which were "want to have (but OK to defer)" when GPIO interfaces were first discussed in November 2006: - A "struct gpio_chip" to plug in GPIOs that aren't directly supported by SOC platforms, but come from FPGAs or other multifunction devices using conventional device registers (like UCB-1x00 or SM501 GPIOs, and southbridges in PCs with more open specs than usual). - Full support for message-based GPIO expanders, where registers are accessed through sleeping I/O calls. Previous support for these "cansleep" calls was just stubs. (One example: the widely used pcf8574 I2C chips, with 8 GPIOs each.) * Including a non-stub implementation of the gpio_{request,free}() calls, making those calls much more useful. The diagnostic labels are also recorded given DEBUG_FS, so /sys/kernel/debug/gpio can show a snapshot of all GPIOs known to this infrastructure. The driver programming interfaces introduced in 2.6.21 do not change at all; this infrastructure is entirely below those covers. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Jean Delvare <khali@linux-fr.org> Cc: Eric Miao <eric.miao@marvell.com> Cc: Haavard Skinnemoen <hskinnemoen@atmel.com> Cc: Philipp Zabel <philipp.zabel@gmail.com> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Ben Gardner <bgardner@wabtec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>