The conversion of the spi-imx driver to use GPIO descriptors
in commit 8cdcd8aeee ("spi: imx/fsl-lpspi: Convert to GPIO descriptors")
helped to detect the following SPI chipselect polarity mismatch on an
imx6q-sabresd:
[ 4.854337] m25p80@0 enforce active low on chipselect handle
Prior to the above commit, the chipselect polarity passed via cs-gpios
property was ignored and considered active-low.
The reason for such mismatch is clearly explained in the comments inside
drivers/gpio/gpiolib-of.c:
* SPI children have active low chip selects
* by default. This can be specified negatively
* by just omitting "spi-cs-high" in the
* device node, or actively by tagging on
* GPIO_ACTIVE_LOW as flag in the device
* tree. If the line is simultaneously
* tagged as active low in the device tree
* and has the "spi-cs-high" set, we get a
* conflict and the "spi-cs-high" flag will
* take precedence.
To properly represent the SPI chipselect polarity, change it to active-low
when the "spi-cs-high" property is absent.
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
The license text has been mangled at some point then copy pasted across
multiple files. Restore it to what it should be.
Note that this is not intended as a license change.
Reviewed-by: Heiko Schocher <hs@denx.de>
Acked-by: Marcel Ziswiler <marcel.ziswiler@toradex.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: Afzal Mohammed <afzal.mohd.ma@gmail.com>
Acked-by: Michael Trimarchi <michael@amarulasolutions.com>
Acked-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Since commit b36581df7e ("spi: imx: Using existing properties for
chipselects") the device tree property 'fsl,spi-num-chipselects' is
unused and it is already marked as obsolete in device tree binding
documentation. Remove the property from the existing DTS files to
avoid its reoccurence on copying.
Signed-off-by: Vladimir Zapolskiy <vz@mleia.com>
Reviewed-by: Fabio Estevam <fabio.estevam@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
These device trees add support for TS-4900 by Technologic Systems.
More details here:
http://wiki.embeddedarm.com/wiki/TS-4900
Signed-off-by: Lucile Quirion <lucile.quirion@savoirfairelinux.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
