The EC has specific timing it requires. Add support for an optional delay
after raising CS to fix timing issues. This is configurable based on
a DT property "google,cros-ec-spi-msg-delay".
If this property isn't set, then no delay will be added. However, if set
it will cause a delay equal to the value passed to it to be inserted at
the end of a transaction.
Signed-off-by: Rhyland Klein <rklein@nvidia.com>
Reviewed-by: Bernie Thompson <bhthompson@chromium.org>
Reviewed-by: Andrew Bresticker <abrestic@chromium.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
memset() was being called with the second parameter set to '\0', which
is equivalent but longer than the more canonical 0. Update the code to
use the latter variant consistently across the driver.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
According to the header comment in the source file the driver is
licensed under GPL v2, so update MODULE_LICENSE() to match that.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Rename cros_ec_{probe,remove}_spi() to cros_ec_spi_{probe,remove}() for
consistency.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
The dev_cont() symbol doesn't exist, so replace it with pr_cont(). While
at it, also append a newline to the debug output to make it look nicer.
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
50 us is not a long enough delay between EC transactions. At least 70 us
are needed for the 16 MHz STM32L part. Increase the delay to 200 us for
an extra safety margin.
Reviewed-by: Randall Spangler <rspangler@chromium.org>
Signed-off-by: Derek Basehore <dbasehore@chromium.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Before commit 5c29e47e6a ("mfd: cros_ec_spi:
Warnings fix"), 64-bit compiles gave the following warnings:
drivers/mfd/cros_ec_spi.c: In function 'cros_ec_spi_receive_response':
drivers/mfd/cros_ec_spi.c:123:5: warning: format '%d' expects argument of type 'int', but argument 4 has type 'long int' [-Wformat]
drivers/mfd/cros_ec_spi.c:157:3: warning: format '%d' expects argument of type 'int', but argument 6 has type 'long int' [-Wformat]
drivers/mfd/cros_ec_spi.c:181:2: warning: format '%d' expects argument of type 'int', but argument 4 has type 'long int' [-Wformat]
After that commit, 32-bit compiles give:
drivers/mfd/cros_ec_spi.c: In function ‘cros_ec_spi_receive_response’:
drivers/mfd/cros_ec_spi.c:123: warning: format ‘%ld’ expects type ‘long int’, but argument 4 has type ‘int’
drivers/mfd/cros_ec_spi.c:157: warning: format ‘%ld’ expects type ‘long int’, but argument 6 has type ‘int’
drivers/mfd/cros_ec_spi.c:181: warning: format ‘%ld’ expects type ‘long int’, but argument 4 has type ‘int’
Use %z to format pointer differences to kill the warnings on both 32-bit
and 64-bit.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
To silent those:
CC [M] drivers/mfd/cros_ec_spi.o
drivers/mfd/cros_ec_spi.c: In function ‘cros_ec_spi_receive_response’:
drivers/mfd/cros_ec_spi.c:123:5: warning: format ‘%d’ expects argument of type
‘int’, but argument 4 has type ‘long int’ [-Wformat]
drivers/mfd/cros_ec_spi.c:157:3: warning: format ‘%d’ expects argument of type
‘int’, but argument 6 has type ‘long int’ [-Wformat]
drivers/mfd/cros_ec_spi.c:181:2: warning: format ‘%d’ expects argument of type
‘int’, but argument 4 has type ‘long int’ [-Wformat]
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
This uses a SPI bus to talk to the ChromeOS EC. The protocol
is defined by the EC and is fairly simple, with a length byte,
checksum, command byte and version byte (to permit easy creation
of new commands).
Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
