Searched hist:c6fe862a (Results 1 – 3 of 3) sorted by relevance
/openbmc/linux/arch/arm64/boot/dts/freescale/ |
H A D | imx8mm-venice-gw72xx.dtsi | c6fe862a Fri Jul 16 08:28:45 CDT 2021 Fabio Estevam <festevam@gmail.com> arm64: dts: imx8mm-venice: Fix the SPI chipselect polarity
The conversion of the spi-imx driver to use GPIO descriptors in commit 8cdcd8aeee28 ("spi: imx/fsl-lpspi: Convert to GPIO descriptors") helped to detect the following SPI chipselect polarity mismatch on an imx6q-sabresd for example:
[ 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: Tim Harvey <tharvey@gateworks.com> Signed-off-by: Shawn Guo <shawnguo@kernel.org>
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H A D | imx8mm-venice-gw71xx.dtsi | c6fe862a Fri Jul 16 08:28:45 CDT 2021 Fabio Estevam <festevam@gmail.com> arm64: dts: imx8mm-venice: Fix the SPI chipselect polarity
The conversion of the spi-imx driver to use GPIO descriptors in commit 8cdcd8aeee28 ("spi: imx/fsl-lpspi: Convert to GPIO descriptors") helped to detect the following SPI chipselect polarity mismatch on an imx6q-sabresd for example:
[ 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: Tim Harvey <tharvey@gateworks.com> Signed-off-by: Shawn Guo <shawnguo@kernel.org>
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H A D | imx8mm-venice-gw73xx.dtsi | c6fe862a Fri Jul 16 08:28:45 CDT 2021 Fabio Estevam <festevam@gmail.com> arm64: dts: imx8mm-venice: Fix the SPI chipselect polarity
The conversion of the spi-imx driver to use GPIO descriptors in commit 8cdcd8aeee28 ("spi: imx/fsl-lpspi: Convert to GPIO descriptors") helped to detect the following SPI chipselect polarity mismatch on an imx6q-sabresd for example:
[ 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: Tim Harvey <tharvey@gateworks.com> Signed-off-by: Shawn Guo <shawnguo@kernel.org>
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