[PATCH 6/8] ARM: dts: imx7d-sdb: Add GPIO expander node

Shawn Guo
2017-04-14T03:47:00Z

On Thu, Apr 13, 2017 at 06:32:40AM -0700, Andrey Smirnov wrote:
> Add node for U38, a 74LV595PW serial-in shift register that acts as a
> GPIO expander on the board.
>
> Cc: yurovsky at gmail.com
> Cc: Sascha Hauer <kernel@pengutronix.de>
> Cc: Fabio Estevam <fabio.estevam@nxp.com>
> Cc: Rob Herring <robh+dt@kernel.org>
> Cc: Mark Rutland <mark.rutland@arm.com>
> Cc: Russell King <linux@armlinux.org.uk>
> Cc: devicetree at vger.kernel.org
> Cc: linux-kernel at vger.kernel.org
> Cc: linux-arm-kernel at lists.infradead.org
> Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
> ---
> arch/arm/boot/dts/imx7d-sdb.dts | 32 ++++++++++++++++++++++++++++++++
> 1 file changed, 32 insertions(+)
>
> diff --git a/arch/arm/boot/dts/imx7d-sdb.dts b/arch/arm/boot/dts/imx7d-sdb.dts
> index 5be01a1..e0ff276 100644
> --- a/arch/arm/boot/dts/imx7d-sdb.dts
> +++ b/arch/arm/boot/dts/imx7d-sdb.dts
> @@ -52,6 +52,30 @@
> reg = <0x80000000 0x80000000>;
> };
>
> + spi4 {
> + compatible = "spi-gpio";
> + pinctrl-names = "default";
> + pinctrl-0 = <&pinctrl_spi1>;
> + status = "okay";

The 'status' is not needed in this case.

> + gpio-sck = <&gpio1 13 0>;
> + gpio-mosi = <&gpio1 9 0>;
> + cs-gpios = <&gpio1 12 0>;
> + num-chipselects = <1>;
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + gpio_spi: gpio_spi at 0 {

gpio-expander might be a better node name?

> + compatible = "fairchild,74hc595";
> + gpio-controller;
> + #gpio-cells = <2>;
> + reg = <0>;
> + registers-number = <1>;
> + /* Enable PERI_3V3, SENSOR_RST_B and HDMI_RST*/
> + registers-default = /bits/ 8 <0x74>;

I do not see this property is documented or supported by kernel.

> + spi-max-frequency = <100000>;
> + };
> + };
> +
> regulators {
> compatible = "simple-bus";
> #address-cells = <1>;
> @@ -642,5 +666,13 @@
> fsl,pins = <
> MX7D_PAD_LPSR_GPIO1_IO01__PWM1_OUT 0x110b0
> >;
> +
> + pinctrl_spi1: spi1grp {
> + fsl,pins = <
> + MX7D_PAD_GPIO1_IO09__GPIO1_IO9 0x59
> + MX7D_PAD_GPIO1_IO12__GPIO1_IO12 0x59
> + MX7D_PAD_GPIO1_IO13__GPIO1_IO13 0x59
> + >;
> + };
> };
> };
> --
> 2.9.3
>