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* mfd: twl4030-gpio driverDavid Brownell2008-10-223-0/+529
| | | | | | | | | | | | | | This adds basic support for the GPIOs in the twl4030 power management chip. That includes two open drain LED drivers, and the use of GPIO-0 (and GPIO-1) as MMC/SD card detect switches which can control whether the VMMC1 (and VMMC2) regulators are active. This version of the code has a debounce call that will probably be replaced before long, when a more generic interface exists. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
* Merge branch 'genirq-v28-for-linus' of ↵Linus Torvalds2008-10-201-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 ...
| * generic: sparse irqs: use irq_desc() together with dyn_array, instead of ↵Yinghai Lu2008-10-161-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | gpiolib: fix oops in gpio_get_value_cansleep()David Brownell2008-10-201-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | gpio: modify sysfs gpio export so that "value" displays as 0 or 1Steven A. Falco2008-10-201-1/+1
| | | | | | | | | | | | | | | | | | | | | | 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>
* | gpiolib: request/free hooksDavid Brownell2008-10-161-13/+78
| | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | gpiolib: gpio_to_irq() hooksDavid Brownell2008-10-161-0/+18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | gpio: i2c expanders use subsys_initDavid Brownell2008-10-163-3/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make the I2C external GPIO expander drivers register themselves at subsys_initcall() time when they're statically linked. SOC-integrated GPIOs are available starting very early -- early in arch_initcall() at latest, but often even before initcalls start to run -- so this improves consistency, so more subsystems can rely on GPIOs in their own subsys_initcall() code. (This isn't a theoretical problem. This is one of several patches needed to resolve oopsing observed when statically linking kernels on a DaVinci EVM. Its pcf857x GPIOs needed to be available well before some other drivers initialized.) Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Jean Delvare <khali@linux-fr.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | gpio_free might sleep, generic partUwe Kleine-König2008-10-161-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | gpio: max7301: fix the race between chip addition and pins reconfigurationDmitry Baryshkov2008-10-161-10/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is a small race and code ugliness in max7301: pins are reconfigured after the chip is registered. Swap these calls so that the device is registered in correct state. Also this fixes the comile-time warning about unchecked gpiochip_remove. Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com> Cc: Juergen Beisert <j.beisert@pengutronix.de> Cc: Guennadi Liakhovetski <g.liakhovetski@pengutronix.de> Cc: Russell King <rmk@arm.linux.org.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>
* | spi: core and gpio expanders use subsys_initDavid Brownell2008-10-162-3/+8
|/ | | | | | | | | | | | | | | Make the SPI external GPIO expander drivers register themselves at subsys_initcall() time when they're statically linked, and make the SPI core do its driver model initialization earlier so that's safe. SOC-integrated GPIOs are available starting very early -- often before initcalls start to run, or earily in arch_initcall() at latest -- so this improves consistency, letting more subsystems rely on GPIOs being usable by their own subsys_initcall() code. 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>
* gpio: max732x driverEric Miao2008-07-253-0/+405
| | | | | | | | | | | | | This adds a driver supporting a family of I2C port expanders from Maxim, which includes the MAX7319 and MAX7320-7327 chips. [dbrownell@users.sourceforge.net: minor fixes] Signed-off-by: Jack Ren <jack.ren@marvell.com> Signed-off-by: Eric Miao <eric.miao@marvell.com> Acked-by: Jean Delvare <khali@linux-fr.org> 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>
* gpiolib: allow user-selectionMichael Buesch2008-07-252-5/+30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds functionality to the gpio-lib subsystem to make it possible to enable the gpio-lib code even if the architecture code didn't request to get it built in. The archtitecture code does still need to implement the gpiolib accessor functions in its asm/gpio.h file. This patch adds the implementations for x86 and PPC. With these changes it is possible to run generic GPIO expansion cards on every architecture that implements the trivial wrapper functions. Support for more architectures can easily be added. Signed-off-by: Michael Buesch <mb@bu3sch.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: David Brownell <david-b@pacbell.net> Cc: Russell King <rmk@arm.linux.org.uk> Cc: Haavard Skinnemoen <hskinnemoen@atmel.com> Cc: Jesper Nilsson <jesper.nilsson@axis.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Ingo Molnar <mingo@elte.hu> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Jean Delvare <khali@linux-fr.org> Cc: Samuel Ortiz <sameo@openedhand.com> Cc: Kumar Gala <galak@gate.crashing.org> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* gpio: add bt8xxgpio driverMichael Buesch2008-07-253-0/+367
| | | | | | | | | | | | | | | | | This adds the bt8xxgpio driver. The purpose of the bt8xxgpio driver is to export all of the 24 GPIO pins available on Brooktree 8xx chips to the kernel GPIO infrastructure. This makes it possible to use a physically modified BT8xx card as cheap digital GPIO card. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Michael Buesch <mb@bu3sch.de> Cc: David Brownell <david-b@pacbell.net> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Mauro Carvalho Chehab <mchehab@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* gpio: mcp23s08 handles multiple chips per chipselectDavid Brownell2008-07-251-31/+102
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Teach the mcp23s08 driver about a curious feature of these chips: up to four of them can share the same chipselect, with the SPI signals wired in parallel, by matching two bits in the first protocol byte against two address lines on the chip. This is handled by three software changes: * Platform data now holds an array of per-chip structs, not just one chip's address and pullup configuration. * Probe() and remove() now use another level of structure, wrapping an instance of the original structure for each mcp23s08 chip sharing that chipselect. * The HAEN bit is set, so that the hardware address bits can no longer be ignored (boot firmware may not have enabled them). The "one struct per chip" preserves the guts of the current code, but platform_data will need minor changes. OLD: /* incorrect "slave" ID may not have mattered */ .slave = 3, .pullups = BIT(3) | BIT(1) | BIT(0), NEW: /* slave address _must_ match chip's wiring */ .chip[3] = { .is_present = true, .pullups = BIT(3) | BIT(1) | BIT(0), }, There's no change in how things _behave_ for spi_device nodes with a single mcp23s08 chip. New multi-chip configurations assign GPIOs in sequence, without holes. The spi_device just resembles a bigger controller, but internally it has multiple gpio_chip instances. 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>
* gpio: sysfs interfaceDavid Brownell2008-07-255-13/+541
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* gpio: pcf857x: add lock and handle more chipsDavid Brownell2008-07-222-6/+32
| | | | | | | | | | | | Two small updates to the pcf857x driver: (a) the max732[89] chips are also second sources for the pcf8574/a, and (b) add a mutex to prevent trashing the cached state. Adding the lock is effectively a bugfix, although it seems unlikely that anyone would have run into the issue it protects against. 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>
* gpio: gpio driver for max7301 SPI GPIO expanderJuergen Beisert2008-07-223-0/+346
| | | | | | | | | | | | | | | Maxim's MAX7301 is an SPI GPIO expander with 28 GPIOs. Note: MAX7301's interrupt feature is not supported yet. [akpm@linux-foundation.org: coding-style fixes] [g.liakhovetski@pengutronix.de: Fix inaccuracies in comments, check spi_setup() return code, mask off high byte in max7301_read()] Signed-off-by: Juergen Beisert <j.beisert@pengutronix.de> Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@pengutronix.de> Cc: Russell King <rmk@arm.linux.org.uk> 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>
* gpio: pca953x (i2c) handles max7310 tooDavid Brownell2008-07-042-5/+11
| | | | | | | | | | The pca953x driver can handle another 8-bit I/O expander, the max7310. This patch adds that chip to the list of supported IDs in that driver, and expands the Kconfig helptext accordingly. 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>
* gpiolib: fix off by one errorsTrent Piepho2008-05-241-3/+3
| | | | | | | | | | 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>
* gpio: mcp23s08 debug fixRoel Kluin2008-05-241-1/+1
| | | | | | | | | The return value of mcp23s08_read_regs() can only be evaluated when signed Signed-off-by: Roel Kluin <12o3l@tiscali.nl> 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>
* gpio: pca953x driver handles pca9554 tooDavid Brownell2008-05-241-0/+1
| | | | | | | | Teach drivers/gpio/pca953x.c about PCA9554, another compatible chip. 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>
* gpio: pca953x: add support for pca9555 I2C I/O expanderWill Newton2008-05-011-1/+3
| | | | | | | | | | | Add support for pca9555 I2C I/O expander. As the comment suggests this part is software compatible with the pca9539. Signed-off-by: Will Newton <will.newton@imgtec.com> Cc: "eric miao" <eric.miao@marvell.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>
* drivers: replace remaining __FUNCTION__ occurrencesHarvey Harrison2008-04-301-2/+2
| | | | | | | | | __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>
* i2c: Convert most new-style drivers to use module aliasingJean Delvare2008-04-292-32/+24
| | | | | | | | | | | | | | Based on earlier work by Jon Smirl and Jochen Friedrich. Update most new-style i2c drivers to use standard module aliasing instead of the old driver_name/type driver matching scheme. I've left the video drivers apart (except for SoC camera drivers) as they're a bit more diffcult to deal with, they'll have their own patch later. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Jon Smirl <jonsmirl@gmail.com> Cc: Jochen Friedrich <jochen@scram.de>
* i2c: Add support for device alias namesJean Delvare2008-04-292-2/+4
| | | | | | | | | | | | | | Based on earlier work by Jon Smirl and Jochen Friedrich. This patch allows new-style i2c chip drivers to have alias names using the official kernel aliasing system and MODULE_DEVICE_TABLE(). At this point, the old i2c driver binding scheme (driver_name/type) is still supported. Signed-off-by: Jean Delvare <khali@linux-fr.org> Cc: Jochen Friedrich <jochen@scram.de> Cc: Jon Smirl <jonsmirl@gmail.com> Cc: Kay Sievers <kay.sievers@vrfy.org>
* gpiochip_reserve()Anton Vorontsov2008-04-281-3/+47
| | | | | | | | | | | | | | 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>
* gpiolib: dynamic gpio number allocationAnton Vorontsov2008-04-281-7/+45
| | | | | | | | | | | | | | | | 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>
* gpio: define gpio_is_valid()Guennadi Liakhovetski2008-04-281-7/+7
| | | | | | | | | | | 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>
* gpiolib: i2c/spi drivers: handle rmmod betterGuennadi Liakhovetski2008-04-283-0/+3
| | | | | | | | | | | | Use the newly introduced owner field in struct gpio_chip to protect the current (small) set of non-SOC GPIO drivers from being unloaded while any of their GPIOs are in use. Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@pengutronix.de> [ add mcp23s08 and pcf857x ] 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>
* gpiolib: better rmmod infrastructureGuennadi Liakhovetski2008-04-281-3/+12
| | | | | | | | | | | | | | | | | 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>
* gpio/pca953x bugfix: mark as can_sleepArnaud Patard2008-03-101-0/+1
| | | | | | | | | | | | | The pca953x driver is an I2C driver so gpio_chip->can_sleep should be set. This lets upper layers know they should use the gpio_*_cansleep() calls to access values, and may not access them from nonsleeping contexts. Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Acked-by: "eric miao" <eric.y.miao@gmail.com> Cc: Jean Delvare <khali@linux-fr.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* gpio: handle pca953{4,5,6,7,8} tooGuennadi Liakhovetski2008-02-061-17/+54
| | | | | | | | | | | | | | This third part of an extension to support more pca953x chips updates the logic to handle the smaller register widths used by the 4-bit and 8-bit parts, and to use the chip type to determine how many GPIOs it provides. As long as we don't support interrupt and reset capabilities, those size issues are the only software-visible differences between these parts. Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@pengutronix.de> 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>
* gpio: rename pca953x symbolsGuennadi Liakhovetski2008-02-063-61/+62
| | | | | | | | | | | This second part of an extension to support more pca953x chips renames the C and Kconfig symbols. All affected files were updated by sed, except for a couple of obvious exceptions. It also updates the Kconfig helptext. Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@pengutronix.de> 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>
* gpio: rename pca9539 driverGuennadi Liakhovetski2008-02-062-2/+2
| | | | | | | | | | | | First part of an extension to let the pca9539 driver support more chips, starting with pca9534, pca9535, pca9536, pca9537, and pca9538. This renames the files and modifies the Makefile. Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@pengutronix.de> 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>
* gpiolib: pca9539 i2c gpio expander supporteric miao2008-02-053-0/+282
| | | | | | | | | | | | | | | | | | | | | | | | | This adds a new-style I2C driver with basic support for the sixteen bit PCA9539 GPIO expanders. These chips have multiple registers, push-pull output drivers, and (not supported in this patch) pin change interrupts. Board-specific code must provide "pca9539_platform_data" with each chip's "i2c_board_info". That provides the GPIO numbers to be used by that chip, and callbacks for board-specific setup/teardown logic. Derived from drivers/i2c/chips/pca9539.c (which has no current known users). This is faster and simpler; it uses 16-bit register access, and cache the OUTPUT and DIRECTION registers for fast access Signed-off-by: eric miao <eric.miao@marvell.com> Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Acked-by: Jean Delvare <khali@linux-fr.org> Cc: Sam Ravnborg <sam@ravnborg.org> 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>
* mcp23s08 spi gpio expander supportDavid Brownell2008-02-053-0/+365
| | | | | | | | | | | | | | | | Basic driver for 8-bit SPI based MCP23S08 GPIO expander, without support for IRQs or the shared chipselect mechanism. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Cc: Jean Delvare <khali@linux-fr.org> Cc: Eric Miao <eric.miao@marvell.com> Cc: Sam Ravnborg <sam@ravnborg.org> 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>
* gpiolib: pcf857x i2c gpio expander supportDavid Brownell2008-02-053-0/+354
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is a new-style I2C driver for most common 8 and 16 bit I2C based "quasi-bidirectional" GPIO expanders: pcf8574 or pcf8575, and several compatible models (mostly faster, supporting I2C at up to 1 MHz). The driver exposes the GPIO signals using the platform-neutral GPIO programming interface, so they are easily accessed by other kernel code. The lack of such a flexible kernel API has been a big factor in the proliferation of board-specific drivers for these chips... stuff that rarely makes it upstream since it's so ugly. This driver will let such boards use standard calls. Since it's a new-style driver, these devices must be configured as part of board-specific init. That eliminates the need for error-prone manual configuration of module parameters, and makes compatibility with legacy drivers (pcf8574.c, pc8575.c) for these chips easier (there's a clear either/or disjunction). Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Acked-by: Jean Delvare <khali@linux-fr.org> Cc: Eric Miao <eric.miao@marvell.com> Cc: Sam Ravnborg <sam@ravnborg.org> 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>
* gpiolib: add gpio provider infrastructureDavid Brownell2008-02-052-0/+569
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* gpiolib: add drivers/gpio directoryDavid Brownell2008-02-052-0/+36
Add an empty drivers/gpio directory for gpiolib infrastructure and GPIO expanders. It will be populated by later patches. This won't be the only place to hold such gpio_chip code. Many external chips add a few GPIOs as secondary functionality (such as MFD drivers) and platform code frequently needs to closely integrate GPIO and IRQ support. This is placed *early* in the build/link sequence since it's common for other drivers to depend on GPIOs to do their work, so they must be initialized early in the device_initcall() sequence. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Acked-by: Jean Delvare <khali@linux-fr.org> Cc: Eric Miao <eric.miao@marvell.com> Cc: Sam Ravnborg <sam@ravnborg.org> 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>
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-27 22:08:18 +0000