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* cros: exynos: add SPI support for cros_ecHung-ying Tyan2013-06-26-0/+16
| | | | | | | | | This patch adds SPI support for carrying out the cros_ec protocol. Signed-off-by: Hung-ying Tyan <tyanh@chromium.org> Signed-off-by: Randall Spangler <rspangler@chromium.org> Signed-off-by: Simon Glass <sjg@chromium.org> Acked-by: Simon Glass <sjg@chromium.org>
* spi: Add support for preamble bytesRajeshwari Shinde2013-06-03-0/+5
| | | | | | | | | | | | | | | | | | | | A SPI slave may take time to react to a request. For SPI flash devices this time is defined as one bit time, or a whole byte for 'fast read' mode. If the SPI slave is another CPU, then the time it takes to react may vary. It is convenient to allow the slave device to tag the start of the actual reply so that the host can determine when this 'preamble' finishes and the actual message starts. Add a preamble flag to the available SPI flags. If supported by the driver then it will ignore any received bytes before the preamble on each transaction. This ensures that reliable communication with the slave is possible. Signed-off-by: Simon Glass <sjg@chromium.org> Signed-off-by: Rajeshwari Shinde <rajeshwari.s@samsung.com> Reviewed-by: Jagannadha Sutradharudu Teki <jagannadh.teki@gmail.com>
* spi: Add parameter for maximum write sizeSimon Glass2013-03-19-0/+3
| | | | | | | | Some SPI controllers (e.g. Intel ICH) have a limit on the number of SPI bytes that can be written at a time. Add this as a parameter so that clients of the SPI interface can respect this value. Signed-off-by: Simon Glass <sjg@chromium.org>
* spi: Add function to allocate a new SPI slaveSimon Glass2013-03-19-0/+41
| | | | | | | | | | At present it is difficult to extend the SPI structure since all drivers allocate it themselves, and few of them zero all fields. Add a new function spi_alloc_slave() which can be used by SPI drivers to perform this allocation, and thus ensure that all drivers can better cope with SPI structure changes. Signed-off-by: Simon Glass <sjg@chromium.org>
* powerpc: eSPI and eSPI controller supportMingkai Hu2011-04-29-7/+0
| | | | | | | | Signed-off-by: Mingkai Hu <Mingkai.hu@freescale.com> Singed-off-by: Jerry Huang <Chang-Ming.Huang@freescale.com> Signed-off-by: Shaohui Xie <b21989@freescale.com> Cc: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
* spi: add spi_set_speed funcThomas Chou2011-04-25-0/+8
| | | | | | | | This func helps mmc_spi driver set correct speed for mmc/sd, as mmc card needs 400KHz clock for spi mode initialization. Signed-off-by: Thomas Chou <thomas@wytron.com.tw> Signed-off-by: Mike Frysinger <vapier@gentoo.org>
* Move conditional compilation of MPC8XXX SPI driver to MakefileBen Warren2008-07-01-0/+9
| | | | Signed-off-by: Ben Warren <biggerbadderben@gmail.com>
* SPI API improvementsHaavard Skinnemoen2008-06-03-23/+127
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch gets rid of the spi_chipsel table and adds a handful of new functions that makes the SPI layer cleaner and more flexible. Instead of the spi_chipsel table, each board that wants to use SPI gets to implement three hooks: * spi_cs_activate(): Activates the chipselect for a given slave * spi_cs_deactivate(): Deactivates the chipselect for a given slave * spi_cs_is_valid(): Determines if the given bus/chipselect combination can be activated. Not all drivers may need those extra functions however. If that's the case, the board code may just leave them out (assuming they know what the driver needs) or rely on the linker to strip them out (assuming --gc-sections is being used.) To set up communication parameters for a given slave, the driver needs to call spi_setup_slave(). This returns a pointer to an opaque spi_slave struct which must be passed as a parameter to subsequent SPI calls. This struct can be freed by calling spi_free_slave(), but most driver probably don't want to do this. Before starting one or more SPI transfers, the driver must call spi_claim_bus() to gain exclusive access to the SPI bus and initialize the hardware. When all transfers are done, the driver must call spi_release_bus() to make the bus available to others, and possibly shut down the SPI controller hardware. spi_xfer() behaves mostly the same as before, but it now takes a spi_slave parameter instead of a spi_chipsel function pointer. It also got a new parameter, flags, which is used to specify chip select behaviour. This may be extended with other flags in the future. This patch has been build-tested on all powerpc and arm boards involved. I have not tested NIOS since I don't have a toolchain for it installed, so I expect some breakage there even though I've tried fixing up everything I could find by visual inspection. I have run-time tested this on AVR32 ATNGW100 using the atmel_spi and DataFlash drivers posted as a follow-up. I'd like some help testing other boards that use the existing SPI API. But most of all, I'd like some comments on the new API. Is this stuff usable for everyone? If not, why? Changed in v4: - Build fixes for various boards, drivers and commands - Provide common struct spi_slave definition that can be extended by drivers - Pass a struct spi_slave * to spi_cs_activate and spi_cs_deactivate - Make default bus and mode build-time configurable - Override default SPI bus ID and mode on mx32ads and imx31_litekit. Changed in v3: - Add opaque struct spi_slave for controller-specific data associated with a slave. - Add spi_claim_bus() and spi_release_bus() - Add spi_free_slave() - spi_setup() is now called spi_setup_slave() and returns a struct spi_slave - soft_spi now supports four SPI modes (CPOL|CPHA) - Add bus parameter to spi_setup_slave() - Convert the new i.MX32 SPI driver - Convert the new MC13783 RTC driver Changed in v2: - Convert the mpc8xxx_spi driver and the mpc8349emds board to the new API. Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Tested-by: Guennadi Liakhovetski <lg@denx.de>
* New i.MX31 SPI driverGuennadi Liakhovetski2008-04-18-1/+15
| | | | | | | | | This is an SPI driver for i.MX and MXC based SoCs from Freescale. So far only implemented and tested on i.MX31, can with a modified register layout and definitions be used for i.MX27, I think, MXC CPUs have similar SPI controllers too. Signed-off-by: Guennadi Liakhovetski <lg@denx.de>
* Initial revisionwdenk2002-09-26-0/+73