In 3-to-8 mux mode for the CS pins we need to set the PERI_SEL bit in the
control register. Currently the driver never sets this bit even when
configured for 3-to-8 mux mode. This patch adds code which sets the bit
during device initialization when necessary.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Acked-by: Harini Katakam <harinik@xilinx.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This will make it possible to use the settings specified in the devicetree
to configure the hardware.
Signed-off-by: Paul Cercueil <paul.cercueil@analog.com>
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Reviewed-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
There is no need to init .owner field.
Based on the patch from Peter Griffin <peter.griffin@linaro.org>
"mmc: remove .owner field for drivers using module_platform_driver"
This patch removes the superflous .owner field for drivers which
use the module_platform_driver API, as this is overriden in
platform_driver_register anyway."
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Currently the cadence SPI driver does the SPI clock configuration (setup CPOL
and CPHA) in the prepare_transfer_hardware() callback. The
prepare_transfer_hardware() callback is only called though when the controller
transitions from a idle state to a non-idle state. Such a transitions happens
when the message queue goes from empty to non-empty. If multiple messages from
different SPI slaves with different clock settings are in the message queue the
clock settings will not be properly updated when switching from one slave device
to another. Instead do the updating of the clock configuration in the
prepare_message() callback which will be called for each individual message.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@linaro.org>
It seems that the cadence SPI controller does not immediately change the clock
polarity setting when writing the CR register. Instead the change is delayed
until the next transfer starts. This happens after the chip select line has
already been asserted. As a result the first transfer after a clock polarity
change will generate spurious clock transitions which typically results in the
SPI slave not being able to properly understand the message. Toggling the ER
register seems to cause the SPI controller to apply the clock polarity changes,
so implement this as a workaround to fix the issue.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@linaro.org>
Make of_device_id array const, because all OF functions handle
it as const.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Harini Katakam <harinik@xilinx.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Add driver for Cadence SPI controller. This is used in Xilinx Zynq.
Signed-off-by: Harini Katakam <harinik@xilinx.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
