[PATCH v4 1/2] drm/bridge: dumb-vga-dac: Support a VDD regulator supply
Archit Taneja
architt at codeaurora.org
Wed Nov 16 23:48:58 PST 2016
Hi,
Thanks for the patch.
On 11/16/2016 09:12 PM, Chen-Yu Tsai wrote:
> Some dumb VGA DACs are active components which require external power.
> Add support for specifying a regulator as its power supply.
>
> Signed-off-by: Chen-Yu Tsai <wens at csie.org>
> Acked-by: Rob Herring <robh at kernel.org>
> ---
> .../bindings/display/bridge/dumb-vga-dac.txt | 2 ++
> drivers/gpu/drm/bridge/dumb-vga-dac.c | 35 ++++++++++++++++++++++
> 2 files changed, 37 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/display/bridge/dumb-vga-dac.txt b/Documentation/devicetree/bindings/display/bridge/dumb-vga-dac.txt
> index 003bc246a270..164cbb15f04c 100644
> --- a/Documentation/devicetree/bindings/display/bridge/dumb-vga-dac.txt
> +++ b/Documentation/devicetree/bindings/display/bridge/dumb-vga-dac.txt
> @@ -16,6 +16,8 @@ graph bindings specified in Documentation/devicetree/bindings/graph.txt.
> - Video port 0 for RGB input
> - Video port 1 for VGA output
>
> +Optional properties:
> +- vdd-supply: Power supply for DAC
>
> Example
> -------
> diff --git a/drivers/gpu/drm/bridge/dumb-vga-dac.c b/drivers/gpu/drm/bridge/dumb-vga-dac.c
> index afec232185a7..15b549f94307 100644
> --- a/drivers/gpu/drm/bridge/dumb-vga-dac.c
> +++ b/drivers/gpu/drm/bridge/dumb-vga-dac.c
> @@ -12,6 +12,7 @@
>
> #include <linux/module.h>
> #include <linux/of_graph.h>
> +#include <linux/regulator/consumer.h>
>
> #include <drm/drmP.h>
> #include <drm/drm_atomic_helper.h>
> @@ -23,6 +24,7 @@ struct dumb_vga {
> struct drm_connector connector;
>
> struct i2c_adapter *ddc;
> + struct regulator *vdd;
> };
>
> static inline struct dumb_vga *
> @@ -124,8 +126,32 @@ static int dumb_vga_attach(struct drm_bridge *bridge)
> return 0;
> }
>
> +static void dumb_vga_enable(struct drm_bridge *bridge)
> +{
> + struct dumb_vga *vga = drm_bridge_to_dumb_vga(bridge);
> + int ret = 0;
> +
> + if (vga->vdd)
> + ret = regulator_enable(vga->vdd);
> +
> + if (ret) {
> + DRM_ERROR("Failed to enable vdd regulator: %d\n", ret);
> + return;
We don't need this return for now. If you're okay with it, can I fix this
and queue to misc?
Thanks,
Archit
> + }
> +}
> +
> +static void dumb_vga_disable(struct drm_bridge *bridge)
> +{
> + struct dumb_vga *vga = drm_bridge_to_dumb_vga(bridge);
> +
> + if (vga->vdd)
> + regulator_disable(vga->vdd);
> +}
> +
> static const struct drm_bridge_funcs dumb_vga_bridge_funcs = {
> .attach = dumb_vga_attach,
> + .enable = dumb_vga_enable,
> + .disable = dumb_vga_disable,
> };
>
> static struct i2c_adapter *dumb_vga_retrieve_ddc(struct device *dev)
> @@ -169,6 +195,15 @@ static int dumb_vga_probe(struct platform_device *pdev)
> return -ENOMEM;
> platform_set_drvdata(pdev, vga);
>
> + vga->vdd = devm_regulator_get_optional(&pdev->dev, "vdd");
> + if (IS_ERR(vga->vdd)) {
> + ret = PTR_ERR(vga->vdd);
> + if (ret == -EPROBE_DEFER)
> + return -EPROBE_DEFER;
> + vga->vdd = NULL;
> + dev_dbg(&pdev->dev, "No vdd regulator found: %d\n", ret);
> + }
> +
> vga->ddc = dumb_vga_retrieve_ddc(&pdev->dev);
> if (IS_ERR(vga->ddc)) {
> if (PTR_ERR(vga->ddc) == -ENODEV) {
>
--
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