android_kernel_xiaomi_sm8350/arch/avr32/mach-at32ap
David Brownell 28735a7253 [PATCH] gpio_direction_output() needs an initial value
It's been pointed out that output GPIOs should have an initial value, to
avoid signal glitching ...  among other things, it can be some time before
a driver is ready.  This patch corrects that oversight, fixing

 - documentation
 - platforms supporting the GPIO interface
 - users of that call (just one for now, others are pending)

There's only one user of this call for now since most platforms are still
using non-generic GPIO setup code, which in most cases already couples the
initial value with its "set output mode" request.

Note that most platforms are clear about the hardware letting the output
value be set before the pin direction is changed, but the s3c241x docs are
vague on that topic ...  so those chips might not avoid the glitches.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Andrew Victor <andrew@sanpeople.com>
Acked-by: Milan Svoboda <msvoboda@ra.rockwell.com>
Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-16 19:25:04 -07:00
..
at32ap7000.c [AVR32] at32_spi_setup_slaves should be __init 2007-03-07 10:50:26 +01:00
at32ap.c [PATCH] AVR32: Allow renumbering of serial devices 2006-10-04 10:25:06 -07:00
clock.c Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm 2007-02-19 13:18:39 -08:00
clock.h [ARM] 4124/1: Rename mach-at91rm9200 and arch-at91rm9200 directories 2007-02-08 14:50:56 +00:00
extint.c [AVR32] ext int fixes 2007-02-09 15:01:57 +01:00
hsmc.c
hsmc.h [PATCH] AVR32: Use __raw MMIO access for internal peripherals 2006-10-25 20:26:33 -07:00
intc.c [AVR32] Implement intc_get_pending() 2006-12-08 13:08:10 +01:00
intc.h [PATCH] AVR32: Use __raw MMIO access for internal peripherals 2006-10-25 20:26:33 -07:00
Makefile [AVR32] GPIO API implementation 2007-02-09 15:01:58 +01:00
pio.c [PATCH] gpio_direction_output() needs an initial value 2007-03-16 19:25:04 -07:00
pio.h [PATCH] AVR32: Use __raw MMIO access for internal peripherals 2006-10-25 20:26:33 -07:00
sm.h [PATCH] AVR32: Use __raw MMIO access for internal peripherals 2006-10-25 20:26:33 -07:00