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>
According to schematics and to RedBoot sources, the MX31ADS uses a 32768Hz
oscillator as a SKIL source. Fix previously wrongly assumed 32000Hz value.
Also fix a typo when verifying a jumper configuration. While at it, make
two needlessly global functions static.
Signed-off-by: Guennadi Liakhovetski <lg@denx.de>
Arithmetic expressions do not get evaluated under stringification. Remove
default network configuration, add DHCP command support. Thanks to Felix
Radensky for reporting.
Signed-off-by: Guennadi Liakhovetski <lg@denx.de>
Update MX31ADS default environment to better match the flash layout and
the memory map, support SPI and RTC.
Signed-off-by: Guennadi Liakhovetski <lg@denx.de>
This patch allows U-Boot to use buffered writes to the Spansion NOR
flash installed on this board, and eliminates long delays in network
transfers after the board startup.
Also modify flash layout to embed main and redundant environment
blocks in the U-Boot image.
Signed-off-by: Guennadi Liakhovetski <lg@denx.de>
This patch adds support for the MX31ADS evaluation board from Freescale,
initialization code is copied from RedBoot sources, also provided by
Freescale.
Signed-off-by: Guennadi Liakhovetski <lg@denx.de>
Reverting became necessary after it turned out that the patches in
the u-boot-arm repo were modified, and in some cases corrupted.
This reverts the following commits:
066bebd6353e33af3adefc3404560871699e9961
7a837b7310166ae8fc8b8d66d7ef01b60a80f9d6
c88ae20580b2b01487b4cdcc8b2a113f551aee36
a147e56f03871bba4f05058d5e04ce7deb010b04
d6674e0e2a6a1f033945f78838566210d3f28c95
8c8463cce44d849e37744749b32d38e1dfb12e50
c98b47ad24b2d91f41c09a3d62d7f70ad84f4b7d
8bf69d81782619187933a605f1a95ee1d069478d
8c16cb0d3b971f46fbe77c072664c0f2dcd4471d
a574a73852a527779234e73e17e7597fd8128882
1377b5583a48021d983e1fd565f7d40c89e84d63
1704dc20917b4f71e373e2c888497ee666d40380
Signed-off-by: Wolfgang Denk <wd@denx.de>
This patch adds support for the MX31ADS evaluation board from Freescale,
initialization code is copied from RedBoot sources, also provided by Freescale.
Signed-off-by: Guennadi Liakhovetski <lg@denx.de>
