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6 commits

Author SHA1 Message Date
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
Haavard Skinnemoen
e7f70b8cc6 [AVR32] Introduce at32_reserve_pin()
at32_reserve_pin() can be used for reserving portmux pins without
altering their configuration. Useful for e.g. SDRAM pins where we
really don't want to change the bootloader-provided configuration.

Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
2007-02-09 15:01:58 +01:00
Haavard Skinnemoen
dde251033f [AVR32] Don't reset PIO state at bootup
Leave the PIO lines as the bootloader left them. This allows us to
use PIOE without disturbing the SDRAM muxing.

Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
2007-02-09 15:01:58 +01:00
Haavard Skinnemoen
6a4e5227a3 [AVR32] GPIO API implementation
Arch-neutral GPIO calls for AVR32. GPIO IRQ support written by
David Brownell.

Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
2007-02-09 15:01:58 +01:00
Haavard Skinnemoen
c3e2a79c0b [AVR32] Portmux API update
Rename portmux_set_func to at32_select_periph, add at32_select_gpio
and add flags parameter to specify the initial state of the pins.

Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
2006-12-08 13:06:17 +01:00
Haavard Skinnemoen
5f97f7f940 [PATCH] avr32 architecture
This adds support for the Atmel AVR32 architecture as well as the AT32AP7000
CPU and the AT32STK1000 development board.

AVR32 is a new high-performance 32-bit RISC microprocessor core, designed for
cost-sensitive embedded applications, with particular emphasis on low power
consumption and high code density.  The AVR32 architecture is not binary
compatible with earlier 8-bit AVR architectures.

The AVR32 architecture, including the instruction set, is described by the
AVR32 Architecture Manual, available from

http://www.atmel.com/dyn/resources/prod_documents/doc32000.pdf

The Atmel AT32AP7000 is the first CPU implementing the AVR32 architecture.  It
features a 7-stage pipeline, 16KB instruction and data caches and a full
Memory Management Unit.  It also comes with a large set of integrated
peripherals, many of which are shared with the AT91 ARM-based controllers from
Atmel.

Full data sheet is available from

http://www.atmel.com/dyn/resources/prod_documents/doc32003.pdf

while the CPU core implementation including caches and MMU is documented by
the AVR32 AP Technical Reference, available from

http://www.atmel.com/dyn/resources/prod_documents/doc32001.pdf

Information about the AT32STK1000 development board can be found at

http://www.atmel.com/dyn/products/tools_card.asp?tool_id=3918

including a BSP CD image with an earlier version of this patch, development
tools (binaries and source/patches) and a root filesystem image suitable for
booting from SD card.

Alternatively, there's a preliminary "getting started" guide available at
http://avr32linux.org/twiki/bin/view/Main/GettingStarted which provides links
to the sources and patches you will need in order to set up a cross-compiling
environment for avr32-linux.

This patch, as well as the other patches included with the BSP and the
toolchain patches, is actively supported by Atmel Corporation.

[dmccr@us.ibm.com: Fix more pxx_page macro locations]
[bunk@stusta.de: fix `make defconfig']
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Dave McCracken <dmccr@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-26 08:48:54 -07:00