This is a doc-only patch which I hope will reduce the number of
spi_master controller driver patches starting out with a common
implementation bug.
(As in: almost every spi_master driver I see starts out with its
version of this bug. Sigh.)
It just re-emphasizes that the setup() method may be called for one
device while a transfer is active on another ... which means that most
driver implementations shouldn't touch any registers.
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>
Noises can be introduced when LCD signals are being driven, some platforms
provide a signal to assist the synchronization of this sampling procedure.
Signed-off-by: Eric Miao <eric.miao@marvell.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
Some SPI controllers have restrictions on DMAable buffers alignemt.
Currently if the buffer supplied by protocol driver is not properly
aligned, the controller silently performs transfer in PIO mode. Addition
of dma_alignment field to spi_master allows protocol drivers to perform
proper alignment.
Signed-off-by: Mike Rapoport <mike@compulab.co.il>
Cc: Bryan Wu <bryan.wu@analog.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>
Change spi-gpio so that it is possible to drive SPI communications over
GPIO without the need for a chipselect signal.
This is useful in very small setups where there's only one slave device
on the bus.
This patch does not affect existing setups.
I use this for a tiny communication channel between an embedded device and
a microcontroller. There are not enough GPIOs available for chipselect
and it's not needed anyway in this case.
Signed-off-by: Michael Buesch <mb@bu3sch.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>
[randy.dunlap@oracle.com: don't use bus_id]
[dtor@mail.ru: locking and other fixups]
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
In certain cases it is required to perform board specific actions
before activating libertas G-SPI interface. These actions may include
power up of the chip, GPIOs setup, proper pin-strapping and SPI
controller config.
This patch adds ability to call board specific setup/teardown methods
Signed-off-by: Mike Rapoport <mike@compulab.co.il>
Acked-by: Andrey Yurovsky <andrey@cozybit.com>
Acked-by: Dan Williams <dcbw@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
fix the following 'make headers_check' warning:
usr/include/linux/spi/spidev.h:83: found __[us]{8,16,32,64} type without #include <linux/types.h>
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Add initial support for libertas devices using a GSPI interface. This has
been tested with the 8686.
GSPI is intended to be used on embedded systems. Board-specific parameters are
required (see libertas_spi.h).
Thanks to everyone who took a look at the earlier versions of the patch.
Signed-off-by: Colin McCabe <colin@cozybit.com>
Signed-off-by: Andrey Yurovsky <andrey@cozybit.com>
Acked-by: Dan Williams <dcbw@redhat.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (24 commits)
trivial: chack -> check typo fix in main Makefile
trivial: Add a space (and a comma) to a printk in 8250 driver
trivial: Fix misspelling of "firmware" in docs for ncr53c8xx/sym53c8xx
trivial: Fix misspelling of "firmware" in powerpc Makefile
trivial: Fix misspelling of "firmware" in usb.c
trivial: Fix misspelling of "firmware" in qla1280.c
trivial: Fix misspelling of "firmware" in a100u2w.c
trivial: Fix misspelling of "firmware" in megaraid.c
trivial: Fix misspelling of "firmware" in ql4_mbx.c
trivial: Fix misspelling of "firmware" in acpi_memhotplug.c
trivial: Fix misspelling of "firmware" in ipw2100.c
trivial: Fix misspelling of "firmware" in atmel.c
trivial: Fix misspelled firmware in Kconfig
trivial: fix an -> a typos in documentation and comments
trivial: fix then -> than typos in comments and documentation
trivial: update Jesper Juhl CREDITS entry with new email
trivial: fix singal -> signal typo
trivial: Fix incorrect use of "loose" in event.c
trivial: printk: fix indentation of new_text_line declaration
trivial: rtc-stk17ta8: fix sparse warning
...
Generalize the old at91rm9200 "bootstrap" bitbanging SPI master driver as
"spi_gpio", so it works with arbitrary GPIOs and can be configured through
platform_data. Such SPI masters support:
- any number of bus instances (bus_num is the platform_device.id)
- any number of chipselects (one GPIO per spi_device)
- all four SPI_MODE values, and SPI_CS_HIGH
- i/o word sizes from 1 to 32 bits;
- devices configured as with any other spi_master controller
When configured using platform_data, this provides relatively low clock
rates. On platforms that support inlined GPIO calls, significantly
improved transfer speeds are also possible with a semi-custom driver.
(It's still painful when accessing flash memory, but less so.)
Sanity checked by using this version to replace both native controllers on
a board with six different SPI slaves, relying on three different
SPI_MODE_* values and both SPI_CS_HIGH settings for correct operation.
[akpm@linux-foundation.org: cleanups]
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Magnus Damm <damm@igel.co.jp>
Tested-by: Magnus Damm <damm@igel.co.jp>
Cc: Torgil Svensson <torgil.svensson@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Include header files as used/needed:
In file included from drivers/leds/leds-dac124s085.c:16:
include/linux/spi/spi.h:66: error: field 'dev' has incomplete type
include/linux/spi/spi.h: In function 'to_spi_device':
include/linux/spi/spi.h💯 warning: type defaults to 'int' in declaration of '__mptr'
...
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The support is implemented via platform data accessors, new module
(of_mmc_spi) will be created automatically when the driver compiles
on OpenFirmware platforms. Link-time dependency will load the module
automatically.
Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>
Fix compile error below:
LD drivers/spi/built-in.o
CC [M] drivers/spi/spi_gpio.o
In file included from drivers/spi/spi_gpio.c:26:
include/linux/spi/spi_bitbang.h:23: error: field `work' has incomplete type
make[2]: *** [drivers/spi/spi_gpio.o] Error 1
make[1]: *** [drivers/spi] Error 2
make: *** [drivers] Error 2
Signed-off-by: Fernando Luis Vazquez Cao <fernando@oss.ntt.co.jp>
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>
This is not generic enough, added here for backward compatibility.
And make this an individual commit so future revert will be a bit
easier.
Signed-off-by: Eric Miao <eric.miao@marvell.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
The driver is based on different source files including corgi_ssp.c,
corgi_lcd.c and corgi_bl.c, previously authored by Richard Purdie
and many others.
The LCD and Backlight device actually share the same SPI device, so
they are made into this single driver.
Signed-off-by: Eric Miao <eric.miao@marvell.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
