aboutsummaryrefslogtreecommitdiff
path: root/drivers/spi/spi-ath79.c
AgeCommit message (Collapse)Author
2014-03-23spi: spi-ath79: fix initial GPIO CS line setupGabor Juhos
commit 61d1cf163c8653934cc8cd5d0b2a562d0990c265 upstream. The 'ath79_spi_setup_cs' function initializes the chip select line of a given SPI device in order to make sure that the device is inactive. If the SPI_CS_HIGH bit is set for a given device, it means that the CS line of that device is active HIGH so it must be set to LOW initially. In case of GPIO CS lines, the 'ath79_spi_setup_cs' function does the opposite of that due to the wrong GPIO flags. Fix the code to use the correct GPIO flags. Reported-by: Ronald Wahl <ronald.wahl@raritan.com> Signed-off-by: Gabor Juhos <juhosg@openwrt.org> Signed-off-by: Mark Brown <broonie@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-02-06spi/ath79: add shutdown handlerGabor Juhos
The SPI controller of the AR7xxx/AR9xxx SoCs have a special mode which allows the SoC to directly read data from SPI flash chips. In this mode, the content of the SPI flash chip can be accessed via a memory mapped region. During early init time, the kernel expects that the flash chip is accessible through that memory region because it reads board specific values (e.g. MAC address, WiFi calibration data) from the flash on various boards. This is working if the kernel is loaded directly by the bootloader because that leaves the SPI controller in the special mode. However it is not working in a kexec'd kernel because the SPI driver does not restore the special mode during shutdown. The patch adds a shutdown handler to fix this issue. Signed-off-by: Gabor Juhos <juhosg@openwrt.org> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2013-02-05spi/ath79: avoid multiple initialization of the SPI controllerGabor Juhos
Currently we are initializing the SPI controller in the chip select line function, and that function is called once for each SPI device on the bus. If a board has multiple SPI devices, the controller will be initialized multiple times. Introduce ath79_spi_{en,dis}able helper functions, and call those from probe/response in order to avoid the mutliple initialization of the controller. Signed-off-by: Gabor Juhos <juhosg@openwrt.org> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2013-02-05spi/ath79: use gpio_request_oneGabor Juhos
Use gpio_request_one() instead of multiple gpiolib calls. Signed-off-by: Gabor Juhos <juhosg@openwrt.org> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2013-02-05spi/ath79: remove superfluous chip select codeGabor Juhos
The spi_bitbang driver calls the chipselect function of the driver from spi_bitbang_setup in order to deselect the given SPI chip, so we don't have to initialize the CS line here. Signed-off-by: Gabor Juhos <juhosg@openwrt.org> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2013-02-05spi/ath79: add missing HIGH->LOW SCK transitionGabor Juhos
The 'ath79_spi_txrx_mode0' function does not set the SCK signal to LOW at the end of a word transfer. This causes communications errors with certain devices (e.g. the PCF2123 RTC chip). The patch ensures that the SCK signal will be LOW. Signed-off-by: Gabor Juhos <juhosg@openwrt.org> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2013-02-05spi/ath79: add delay between SCK changesGabor Juhos
The driver uses the "as fast as it can" approach to drive the SCK signal. However this does not work with certain low speed SPI chips (e.g. the PCF2123 RTC chip). The patch adds per-bit slowdowns in order to be able to use the driver with such chips as well. Signed-off-by: Gabor Juhos <juhosg@openwrt.org> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-12-07spi: Remove HOTPLUG section attributesGrant Likely
CONFIG_HOTPLUG is going away as an option. As result the __dev* markings will be going away. Remove use of __devinit, __devexit_p, __devinitdata, __devinitconst, and __devexit. Bill Pemberton has done most of the legwork on this series. I've used his script to purge the attributes from the drivers/gpio tree. Reported-by: Bill Pemberton <wfp5p@virginia.edu> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2012-05-19spi: By default setup spi_masters with 1 chipselect and dynamics bus numberGrant Likely
Trivial simplification. Instead of requiring spi master drivers to always set the bus number (even when a dynamic number is desired), this patch modifies spi_alloc_master() to initialize num_chipselect to 1 (because there will always be at least one CS) and bus_num to -1 for dynamic allocation. This simplifies the code needed to be written for drivers. Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-12-07spi/ath79: fix compile error due to missing includeGabor Juhos
Whithout including 'linux/module.h' spi-ath79 driver fails to compile with the these errors: drivers/spi/spi-ath79.c:273:12: error: 'THIS_MODULE' undeclared here (not in a function) drivers/spi/spi-ath79.c:278:20: error: expected declaration specifiers or '...' before string constant drivers/spi/spi-ath79.c:278:1: warning: data definition has no type or storage class drivers/spi/spi-ath79.c:278:1: warning: type defaults to 'int' in declaration of 'MODULE_DESCRIPTION' drivers/spi/spi-ath79.c:278:20: warning: function declaration isn't a prototype drivers/spi/spi-ath79.c:279:15: error: expected declaration specifiers or '...' before string constant drivers/spi/spi-ath79.c:279:1: warning: data definition has no type or storage class drivers/spi/spi-ath79.c:279:1: warning: type defaults to 'int' in declaration of 'MODULE_AUTHOR' drivers/spi/spi-ath79.c:279:15: warning: function declaration isn't a prototype drivers/spi/spi-ath79.c:280:16: error: expected declaration specifiers or '...' before string constant drivers/spi/spi-ath79.c:280:1: warning: data definition has no type or storage class drivers/spi/spi-ath79.c:280:1: warning: type defaults to 'int' in declaration of 'MODULE_LICENSE' drivers/spi/spi-ath79.c:280:16: warning: function declaration isn't a prototype drivers/spi/spi-ath79.c:281:14: error: expected declaration specifiers or '...' before string constant drivers/spi/spi-ath79.c:281:1: warning: data definition has no type or storage class drivers/spi/spi-ath79.c:281:1: warning: type defaults to 'int' in declaration of 'MODULE_ALIAS' drivers/spi/spi-ath79.c:281:14: warning: function declaration isn't a prototype Signed-off-by: Gabor Juhos <juhosg@openwrt.org> Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2011-10-25drivercore: Add helper macro for platform_driver boilerplateGrant Likely
For simple modules that contain a single platform_driver without any additional setup code then ends up being a block of duplicated boilerplate. This patch adds a new macro, module_platform_driver(), which replaces the module_init()/module_exit() registrations with template functions. Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Reviewed-by: Magnus Damm <magnus.damm@gmail.com> Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>
2011-06-10spi: Convert uses of struct resource * to resource_size(ptr)Joe Perches
Done via coccinelle scripts like: @@ struct resource *ptr; @@ - ptr->end - ptr->start + 1 + resource_size(ptr) and some grep and typing. Mostly uncompiled, no cross-compilers. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
2011-06-06spi: reorganize driversGrant Likely
Sort the SPI makefile and enforce the naming convention spi_*.c for spi drivers. This change also rolls the contents of atmel_spi.h into the .c file since there is only one user of that particular include file. v2: - Use 'spi-' prefix instead of 'spi_' to match what seems to be be the predominant pattern for subsystem prefixes. - Clean up filenames in Kconfig and header comment blocks Signed-off-by: Grant Likely <grant.likely@secretlab.ca> Acked-by: Wolfram Sang <w.sang@pengutronix.de> Acked-by: Linus Walleij <linus.walleij@linaro.org>