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3 commits

Author SHA1 Message Date
Mika Westerberg
a0d2642e92 spi/pxa2xx: add support for Intel Low Power Subsystem SPI
Intel LPSS SPI is pretty much the same as the PXA27xx SPI except that it
has few additional features over the original:

	o FIFO depth is 256 entries
	o RX FIFO has one watermark
	o TX FIFO has two watermarks, low and high
	o chip select can be controlled by writing to a register

The new FIFO registers follow immediately the PXA27xx registers but then there
are some additional LPSS private registers at offset 1k or 2k from the base
address. For these private registers we add new accessors that take advantage
of drv_data->lpss_base once it is resolved.

We add a new type LPSS_SSP that can be used to distinguish the LPSS devices
from others.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Lu Cao <lucao@marvell.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-02-08 13:14:40 +00:00
Mika Westerberg
5928808ef6 spi/pxa2xx: add support for DMA engine
To be able to use DMA with this driver on non-PXA platforms we implement
support for the generic DMA engine API. This lets user to use different DMA
engines with little or no modification to the driver.

Request lines and channel numbers can be passed to the driver from the
platform specific data.

The DMA engine implementation will be selected by default even on PXA
platform. User can select the legacy DMA API by enabling Kconfig option
CONFIG_SPI_PXA2XX_PXADMA.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Lu Cao <lucao@marvell.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-02-08 12:15:28 +00:00
Mika Westerberg
cd7bed0034 spi/pxa2xx: break out the private DMA API usage into a separate file
The PXA SPI driver uses PXA platform specific private DMA implementation
which does not work on non-PXA platforms. In order to use this driver on
other platforms we break out the private DMA implementation into a separate
file that gets compiled only when CONFIG_SPI_PXA2XX_PXADMA is set. The DMA
functions are stubbed out if there is no DMA implementation selected (i.e
we are building on non-PXA platform).

While we are there we can kill the dummy DMA bits in pxa2xx_spi.h as they
are not needed anymore for CE4100.

Once this is done we can add the generic DMA engine support to the driver
that allows usage of any DMA controller that implements DMA engine API.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Tested-by: Lu Cao <lucao@marvell.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2013-02-08 12:15:21 +00:00