[PATCH V7 2/7] ARM: dts: imx6q-dhcom: Rework of the DHCOM GPIO pinctrls

[Shawn Guo]

On Mon, Aug 02, 2021 at 04:10:33PM +0200, Christoph Niedermaier wrote:
> The function of each SoM pins is defined in the DHCOM standard [1] and
> subset of them is defined as GPIOs (pins A-W). To ensure the interchange-
> ability of the DHCOM SoMs, the function of the pins are fixed and cannot
> be changed. On board level the DHCOM GPIOs can be used associated with
> different blocks e.g. for interrupt or reset, but the function is always
> GPIO. If not used, they can be freely used in the user space.
> 
> Therefore the whole configuration of SoM pins is made in the SoM DT.
> Defining the DHCOM GPIO pins as a separate pinctrl nodes makes moving a
> subset of them to an appropriate block pinctrl group easier on board level,
> since it is not necessary to have a large pinctrl hog group containing
> unrelated pinmux entries on board level. This also makes it easy to update
> the SoM DT without having to update all the board DTs too. If necessary it
> is also possible to change the electrical properties of the DHCOM GPIOs by
> overwriting the pinctrl on board level.
> 
> [1] https://wiki.dh-electronics.com/images/2/2e/DOC_DHCOM-Standard-Specification_R01_2016-11-17.pdf
> 
> Signed-off-by: Christoph Niedermaier <cniedermaier at dh-electronics.com>
> Cc: Shawn Guo <shawnguo at kernel.org>
> Cc: Fabio Estevam <festevam at denx.de>
> Cc: Marek Vasut <marex at denx.de>
> Cc: NXP Linux Team <linux-imx at nxp.com>
> Cc: kernel at dh-electronics.com
> To: linux-arm-kernel at lists.infradead.org

Applied, thanks!