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path: root/drivers/mfd
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2008-10-19mfd: ucb1400 sound driver uses/depends on AC97_BUS:Randy Dunlap
ERROR: "ac97_bus_type" [drivers/mfd/ucb1400_core.ko] undefined! Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Samuel Ortiz <sameo@openedhand.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2008-10-19mfd: Don't use NO_IRQ in WM8350Mark Brown
NO_IRQ is only defined on some architectures - the general way to test for an invalid IRQ in the modern kernel is by comparing with zero. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
2008-10-19mfd: update TMIO drivers to use the clock APIIan Molton
This patch updates the remaining two TMIO drivers to use the clock API rather than callback hooks into platform code. Signed-off-by: Ian Molton <spyro@f2s.com> Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
2008-10-19mfd: twl4030-core irq simplificationDavid Brownell
Simplify twl4030 IRQ handling by removing a needless custom flow handler. The top level IRQs, from the PIH, are well suited for handle_simple_irq() ... they can't be acked or masked. Switching resolves some issues with how IRQs were dispatched. Notably, abuse of desc->status, IRQ accounting, and handling of various faults. In short, use standard genirq code. Drivers that request_irq() to the PIH will need to pay more attention to things like setting IRQF_DISABLED (since it's no longer ignored), and making I2C calls from handlers (you'll need a lockdep workaround). 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>
2008-10-19mfd: add base support for Dialog DA9030/DA9034 PMICsEric Miao
DA9030 (a.k.a ARAVA) and DA9034 (a.k.a MICCO) are PMICs designed by Dialog Semiconductor, usually found on PXA-based platforms. These PMICs are I2C-based, multi-function devices, usually with LEDs, PWMs for backlight, BUCKs and LDOs, ADCs and touchscreen controller (on DA9034). This is the base support for the I2C operations, event registration and handling, sub-devices management. Signed-off-by: Mike Rapoport <mike@compulab.co.il> Signed-off-by: Eric Miao <eric.miao@marvell.com> Signed-off-by: Liam Girdwood <lrg@kernel.org> Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
2008-10-19mfd: TWL4030 core driverDavid Brownell
This patch adds the core of the TWL4030 driver, which supports chips including the TPS65950. These chips are multi-function; see http://focus.ti.com/docs/prod/folders/print/tps65950.html Public specs are in the works. For now, the block diagram on the second page of the datasheet is fairly informative. There are some known issues with this core code. Most notably, the IRQ dispatching needs simplification (to use more of genirq), generalization (integrating support for secondary IRQ dispatch as well as primary, and removing the build dependency on OMAP), and then probably updating to leverage threaded IRQ support (expected to arrive in mainline "soon"). Once the core is in mainline, drivers for other parts of this chip can follow its lead and start swimming upstream too. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
2008-10-19mfd: support tmiofb cell on tc6393xbDmitry Baryshkov
Add support for tmiofb cell found in tc6393xb chip. Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com> Cc: Ian Molton <spyro@f2s.com> Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
2008-10-19mfd: add OHCI cell to tc6393xbDmitry Baryshkov
Add information regarding OHCI cell of the tc6393xb Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com> Acked-by: Ian Molton <spyro@f2s.com> Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
2008-10-19mfd: Fix htc-egpio compile warningSamuel Ortiz
resource_size_t can be a 64 bits value. Since this is just a printk, we'll cast it to a u32. Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
2008-10-19mfd: do tcb6393xb state restore on resume only if requestedDmitry Baryshkov
As requested by Ian make state restore only if it's requested by platform data: some platforms do correctly save the state of the chip during suspend/resume, but some (like tosa) incorrectly power off the chip at suspend, so the driver supports restoring some bits of the tc6393xb state (not full, merely enough to support resume on tosa). With this patch this code is disabled by default. Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com> Acked-by: Ian Molton <spyro@f2s.com> Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
2008-10-19mfd: provide and use setup hook for tc6393xbDmitry Baryshkov
Instead of using bitfields for initial gpio setup, provide generic setup/teardown hooks that can be used to set the gpio states, register child devices, etc. Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com> Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
2008-10-19mfd: update sm501 debugging/low information messagesBen Dooks
Make the default output of the SM501 driver to be less noisy wrt to message that have low informational value, or simply should be debug. Signed-off-by: Ben Dooks <ben-linux@fluff.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
2008-10-19mfd: reduce stack usage in mfd-core.cIan Molton
This patch moves the allocation of the resources off the stack in mfd_add_device(). Signed-off-by: Ian Molton <spyro@f2s.com> Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
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>
2008-10-13mfd: Fix warning in WM8350Mark Brown
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Samuel Ortiz <sameo@openedhand.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2008-10-13mfd: Add placeholders for WM8350 client devicesMark Brown
In order to avoid merge problems further down the line add placeholders for several of the WM8350 client devices and register them, otherwise the patches adding the client devices will all try to update the same code. Also remove redundant checks for null regulator platform devices while we're at it. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Samuel Ortiz <sameo@openedhand.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2008-10-13mfd: Add WM8350 subdevice registration helperMark Brown
Most of the subdevices for the WM8350 code are registered in the same fashion so factor out the code to do the initial registration. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Samuel Ortiz <sameo@openedhand.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2008-10-13regulator: Add WM8350 regulator supportMark Brown
The WM8350 features six DCDC convertors (four buck and two boost), four LDO voltage regulators and two constant current sinks. This driver adds support for these through the regulator API. This driver was written by Liam Girdwood with updates for submission from Mark Brown. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2008-10-13mfd: Add WM8350 interrupt supportMark Brown
The WM8350 has an interrupt line to the CPU which is shared by the devices on the CPU. This patch adds support for the interrupt controller within the WM8350 which identifies which identifies the interrupt cause. In common with other similar chips this is done outside the standard interrupt framework due to the need to access the interrupt controller over an interrupt-driven bus. This code was all originally written by Liam Girdwood with updates for submission by me. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Samuel Ortiz <sameo@openedhand.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2008-10-13mfd: Add initialisation callback for WM8350Mark Brown
Some functions of the WM8350 require board-specific initialisation on startup. Provide a callback to the WM8350 driver in platform data for platforms to use to configure the chip. Use of a callback allows platforms to control the ordering of initialisation which can be important. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Samuel Ortiz <sameo@openedhand.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2008-10-13mfd: Add GPIO pin configuration support for WM8350Mark Brown
The WM8350 provides a number of user-configurable pins providing access to various signals generated by the functions on the chip. These are referred to as GPIO pins in the device documentation but in Linux terms they are more general than that, providing configuration of alternate functions. This patch implements support for selecting the alternate functions for these pins. They can also be used as GPIOs in the normal Linux sense - a subsequent patch will add support for doing so. This code was all written by Liam Girdwood and has had minor updates and rearrangements by Mark Brown. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Samuel Ortiz <sameo@openedhand.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2008-10-13mfd: Add I2C control support for WM8350Mark Brown
Implement the I2C control interface for the WM8350. This code was originally written by Liam Girdwood and has been updated for submission by Mark Brown. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Samuel Ortiz <sameo@openedhand.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2008-10-13mfd: Core support for the WM8350 AudioPlus PMICMark Brown
The WM8350 is an integrated audio and power management subsystem intended for use as the primary PMIC in mobile multimedia applications. The WM8350 can be controlled via either I2C or SPI - the control interface is provided by a separate module in order to allow greatest flexibility in configuring the kernel. This driver was originally written by Liam Girdwood and has since been updated to current kernel APIs and split up for submission by me. All the heavy lifting here was done by Liam. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Samuel Ortiz <sameo@openedhand.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2008-10-13mfd: Core support for the WM8400 AudioPlus HiFi CODEC and PMUMark Brown
The WM8400 is a highly integrated audio CODEC and power management unit optimised for use in mobile multimedia applications. This patch adds core support for the WM8400 to the MFD subsystem. Both I2C and SPI access are supported by the hardware but currently only I2C access is implemented. The code is structured to allow SPI support to be slotted in later. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Samuel Ortiz <sameo@openedhand.com> Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2008-10-11Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-armLinus Torvalds
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (236 commits) [ARM] 5300/1: fixup spitz reset during boot [ARM] 5295/1: make ZONE_DMA optional [ARM] 5239/1: Palm Zire 72 power management support [ARM] 5298/1: Drop desc_handle_irq() [ARM] 5297/1: [KS8695] Fix two compile-time warnings [ARM] 5296/1: [KS8695] Replace macro's with trailing underscores. [ARM] pxa: allow multi-machine PCMCIA builds [ARM] pxa: add preliminary CPUFREQ support for PXA3xx [ARM] pxa: add missing ACCR bit definitions to pxa3xx-regs.h [ARM] pxa: rename cpu-pxa.c to cpufreq-pxa2xx.c [ARM] pxa/zylonite: add support for USB OHCI [ARM] ohci-pxa27x: use ioremap() and offset for register access [ARM] ohci-pxa27x: introduce pxa27x_clear_otgph() [ARM] ohci-pxa27x: use platform_get_{irq,resource} for the resource [ARM] ohci-pxa27x: move OHCI controller specific registers into the driver [ARM] ohci-pxa27x: introduce flags to avoid direct access to OHCI registers [ARM] pxa: move I2S register and bit definitions into pxa2xx-i2s.c [ARM] pxa: simplify DMA register definitions [ARM] pxa: make additional DCSR bits valid for PXA3xx [ARM] pxa: move i2c register and bit definitions into i2c-pxa.c ... Fixed up conflicts in arch/arm/mach-versatile/core.c sound/soc/pxa/pxa2xx-ac97.c sound/soc/pxa/pxa2xx-i2s.c manually.
2008-10-07Merge branch 'pxa-palm' into pxa-machinesRussell King
Conflicts: drivers/mfd/Kconfig drivers/pcmcia/Makefile
2008-09-30mfd: Fix asic3 compilationSamuel Ortiz
map_size was declared from the wrong place. Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
2008-09-30mfd: Fix Kconfig accroding to the new gpiolib symbolsSamuel Ortiz
HAVE_GPIO_LIB has basically been replaced by GPIOLIB Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
2008-08-23removed unused #include <linux/version.h>'sAdrian Bunk
This patch lets the files using linux/version.h match the files that #include it. Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-08-20[ARM] 5184/1: Split ucb1400_ts into core and touchscreenMarek Vašut
This patch splits ucb1400_ts into ucb1400_ts and ucb1400_core. Since this chip supports more features than only touchscreen, it was necessary to prepare it for feature addition. The previous functionality is preserved by applying this patch. [Build fixes for non-ARM by Stephen Rothwell and Takashi Iwai] Signed-off-by: Marek Vasut <marek.vasut@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-08-10mfd: tc6393 cleanup and updateIan Molton
This patchset cleans up the TC6393XB support. * Add provision for the MMC subdevice * Disable / enable clocks on suspend / resume * Remove fragments of badly merged code (eg. linux/fb include etc.) * Use a device specific clock name to break dependancy on ARM/PXA2XX * Drop unnecessary resource names * Switch to tmio_io* accessors Signed-off-by: Ian Molton <spyro@f2s.com> Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
2008-08-10mfd: have TMIO drivers and subdevices depend on ARMSamuel Ortiz
The TMIO chips are only found (and thus tested) on ARM machines. Moreover, we don't want the TMIO cells to be built if one of the TMIO driver is not selected (which indirectly make the TMIO cells drivers depend on ARM as well). Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
2008-08-10mfd: t7l66 MMC platform dataIan Molton
The tmio MMC driver needs the cell to be passed as a platform data. Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
2008-08-10mfd: tc6387 MMC platform dataIan Molton
We need to pass the cell as the platform data. Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
2008-08-10mfd: Fix 7l66 and 6387 according to the new mfd-core APISamuel Ortiz
Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
2008-08-10mfd: Fix tc6393 according to the new tmio.hSamuel Ortiz
Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
2008-08-10mfd: driver for the TC6387XB TMIO controller.Ian Molton
This patch adds support for the TC6387XB. Unlike other TMIO devices this one has only one subdevice and no interrupt mux, however using the MFD framework allows it to share the TMIO MMC driver. Signed-off-by: Ian Molton <spyro@f2s.com> Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
2008-08-10mfd: driver for the T7L66XB TMIO SoCIan Molton
This patchset provides support for the core functinality of the T7L66XB SoC from Toshiba. Supported in this patchset is the IRQ MUX, MMC controller and NAND flash controller. Signed-off-by: Ian Molton <spyro@f2s.com> Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
2008-08-07[ARM] Move include/asm-arm/arch-* to arch/arm/*/include/machRussell King
This just leaves include/asm-arm/plat-* to deal with. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-08-07Merge git://git.kernel.org/pub/scm/linux/kernel/git/sam/kbuild-fixesRussell King
2008-08-07[ARM] Remove asm/hardware.h, use asm/arch/hardware.h insteadRussell King
Remove includes of asm/hardware.h in addition to asm/arch/hardware.h. Then, since asm/hardware.h only exists to include asm/arch/hardware.h, update everything to directly include asm/arch/hardware.h and remove asm/hardware.h. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-07-29mfd: accept pure device as a parent, not only platform_deviceDmitry Baryshkov
Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com> Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
2008-07-29mfd: add platform_data to mfd_cellMike Rapoport
Adding platform_data to mfd_cell allows passing of platform data directly to the platform_device created for each cell and thus reuse of existing drivers. On the other side it can be used as a hook to mfd_cell itself removing the need in mfd_get_cell method. Signed-off-by: Mike Rapoport <mike@compulab.co.il> Acked-by: Dmitry Baryshkov <dbaryshkov@gmail.com> Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
2008-07-28mfd: Coding style fixesBen Dooks
Fix some coding style fixes in the mfd core driver. Signed-off-by: Ben Dooks <ben-linux@fluff.org> Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
2008-07-28mfd: Use to_platform_device instead of container_ofBen Dooks
Convert mfd_remove_devices_fn() to use to_platform_device() instead of doing container_of(). Signed-off-by: Ben Dooks <ben-linux@fluff.org> Acked-by: Dmitry Baryshkov <dbaryshkov@gmail.com> Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
2008-07-27[ARM] 5179/1: Replace obsolete IRQT_* and __IRQT_* values with IRQ_TYPE_*Dmitry Baryshkov
IRQT_* and __IRQT_* were obsoleted long ago by patch [3692/1]. Remove them completely. Sed script for the reference: s/__IRQT_RISEDGE/IRQ_TYPE_EDGE_RISING/g s/__IRQT_FALEDGE/IRQ_TYPE_EDGE_FALLING/g s/__IRQT_LOWLVL/IRQ_TYPE_LEVEL_LOW/g s/__IRQT_HIGHLVL/IRQ_TYPE_LEVEL_HIGH/g s/IRQT_RISING/IRQ_TYPE_EDGE_RISING/g s/IRQT_FALLING/IRQ_TYPE_EDGE_FALLING/g s/IRQT_BOTHEDGE/IRQ_TYPE_EDGE_BOTH/g s/IRQT_LOW/IRQ_TYPE_LEVEL_LOW/g s/IRQT_HIGH/IRQ_TYPE_LEVEL_HIGH/g s/IRQT_PROBE/IRQ_TYPE_PROBE/g s/IRQT_NOEDGE/IRQ_TYPE_NONE/g Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
2008-07-26asic3: platform_get_irq() may return signed unnoticedRoel Kluin
asic->irq_nr is unsigned. platform_get_irq() may return signed unnoticed Signed-off-by: Roel Kluin <12o3l@tiscali.nl> Cc: Joe Perches <joe@perches.com> Acked-by: Samuel Ortiz <sameo@openedhand.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25MFD_TC6393XB is ARM-onlyAdrian Bunk
Compile error on other architectures: CC drivers/mfd/tc6393xb.o /home/bunk/linux/kernel-2.6/git/linux-2.6/drivers/mfd/tc6393xb.c: In function ‘tc6393xb_attach_irq’: /home/bunk/linux/kernel-2.6/git/linux-2.6/drivers/mfd/tc6393xb.c:324: error: implicit declaration of function ‘set_irq_flags’ ... Reported-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: Adrian Bunk <bunk@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-25gpiolib: allow user-selectionMichael Buesch
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>
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>