linux.git/include/asm-generic/gpio.h, branch v2.6.35

gpiolib: introduce set_debounce method

2010-05-27T16:12:42+00:00

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 
Cc: Tony Lindgren 
Cc: David Brownell 
Reviewed-by: Mark Brown 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

gpiolib: document that names can contain printk format specifiers

2010-05-27T16:12:41+00:00

Signed-off-by: Uwe Kleine-König 
Cc: David Brownell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

gpiolib: make names array and its values const

2010-05-27T16:12:41+00:00

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 
Cc: Kevin Wells 
Cc: David Brownell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

gpio: introduce gpio_request_one() and friends

2010-03-06T19:26:48+00:00

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 
Cc: David Brownell 
Cc: Ben Nizette 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

gpiolib: add support for changing value polarity in sysfs

2009-12-16T15:20:01+00:00

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 
Cc: David Brownell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

asm-generic/gpio.h: add some forward decls of the device struct

2009-12-10T21:18:33+00:00

After the recent commit a4177ee7f, attempting to include asm-generic/gpio.h
in otherwise "slim" code results in ugly warnings like so:

  CC      arch/blackfin/kernel/bfin_gpio.o
In file included from arch/blackfin/include/asm/gpio.h:278,
                 from arch/blackfin/kernel/bfin_gpio.c:15:
include/asm-generic/gpio.h:193: warning:
‘struct device’ declared inside parameter list
its scope is only this definition or declaration, which is probably not what you want

So add simple C forward decls of the struct device to avoid these.

Signed-off-by: Mike Frysinger 
Signed-off-by: Arnd Bergmann

asm-generic/gpio.h: pull in linux/kernel.h for might_sleep()

2009-10-01T23:11:11+00:00

The asm-generic/gpio.h header uses the might_sleep() macro but doesn't
include the header for it, so any source code that might include
linux/gpio.h before linux/kernel.h can easily lead to a build failure.

Signed-off-by: Mike Frysinger 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

gpiolib: allow exported GPIO nodes to be named using sysfs links

2009-09-23T14:39:46+00:00

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 
Acked-by: David Brownell 
Cc: Daniel Silverstone 
Signed-off-by: Randy Dunlap 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

gpiolib: allow GPIOs to be named

2009-04-03T02:04:51+00:00

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 
Cc: David Brownell 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

gpiolib: request/free hooks

2008-10-16T18:21:40+00:00

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 
Cc: "Magnus Damm" 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds