[PATCH 4/4] ARM: dts: da850-evm: add the UI expander node
Sekhar Nori
nsekhar at ti.com
Mon Feb 20 01:36:44 PST 2017
On Thursday 16 February 2017 11:45 PM, Bartosz Golaszewski wrote:
> If we're using the UI board and want vpif capture, we need to select
> the video capture functionality by driving the sel_c pin low on the
> tca6416 expander and sel_a & sel_b pins high. Do it statically by
> hogging relevant GPIOs in the device tree.
>
> Signed-off-by: Bartosz Golaszewski <bgolaszewski at baylibre.com>
> ---
> arch/arm/boot/dts/da850-evm.dts | 27 +++++++++++++++++++++++++++
> 1 file changed, 27 insertions(+)
>
> diff --git a/arch/arm/boot/dts/da850-evm.dts b/arch/arm/boot/dts/da850-evm.dts
> index b549861..a90c764 100644
> --- a/arch/arm/boot/dts/da850-evm.dts
> +++ b/arch/arm/boot/dts/da850-evm.dts
> @@ -9,6 +9,7 @@
> */
> /dts-v1/;
> #include "da850.dtsi"
> +#include <dt-bindings/gpio/gpio.h>
>
> / {
> compatible = "ti,da850-evm", "ti,da850";
> @@ -78,7 +79,33 @@
> DRVDD-supply = <&vbat>;
> DVDD-supply = <&vbat>;
> };
> + ui_expander: tca6416 at 20 {
This should be called:
tca6416: gpio at 20 {
in keeping with ePAPR 1.1 generic node names recommendation.
> + compatible = "ti,tca6416";
> + reg = <0x20>;
> + gpio-controller;
> + #gpio-cells = <2>;
>
> + sel_a {
> + gpio-hog;
> + gpios = <7 GPIO_ACTIVE_HIGH>;
> + output-high;
> + line-name = "sel_a";
> + };
> +
> + sel_b {
> + gpio-hog;
> + gpios = <6 GPIO_ACTIVE_HIGH>;
> + output-high;
> + line-name = "sel_b";
> + };
> +
> + sel_c {
> + gpio-hog;
> + gpios = <5 GPIO_ACTIVE_HIGH>;
> + output-low;
> + line-name = "sel_c";
I think this is better handled by using an enable-gpios property in vpif
capture device-tree node. So in the vpif capture node you would have:
enable-gpios = <&tca6416 7 GPIO_ACTIVE_HIGH
&tca6416 6 GPIO_ACTIVE_HIGH
&tca6416 5 GPIO_ACTIVE_LOW>;
and in the vpif capture driver, you would request each of these gpios
using: devm_gpiod_get_array_optional(.., .., GPIOD_OUT_HIGH);
Thanks,
Sekhar
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