Re: [PATCH v3 5/5] drm/bridge: lvds-encoder: add powerdown-gpios support

2019-01-22 Thread Laurent Pinchart
Hi Peter,

Thank you for the patch.

On Sat, Dec 29, 2018 at 07:07:43AM +, Peter Rosin wrote:
> Optionally power down the LVDS-encoder when it is not in use.
> 
> Signed-off-by: Peter Rosin 

As the powerdown-gpios property is only defined for two encoders, and
both of them should work well with this code, I think the change is
fine. In the future if different power-up/down sequences need to be
implemented for different devices this will need to be made
device-specific.

> ---
>  drivers/gpu/drm/bridge/lvds-encoder.c | 34 ++
>  1 file changed, 34 insertions(+)
> 
> diff --git a/drivers/gpu/drm/bridge/lvds-encoder.c 
> b/drivers/gpu/drm/bridge/lvds-encoder.c
> index f6770e83d49d..36d8557bc097 100644
> --- a/drivers/gpu/drm/bridge/lvds-encoder.c
> +++ b/drivers/gpu/drm/bridge/lvds-encoder.c
> @@ -11,11 +11,13 @@
>  #include 
>  #include 
>  
> +#include 
>  #include 
>  
>  struct lvds_encoder {
>   struct drm_bridge bridge;
>   struct drm_bridge *panel_bridge;
> + struct gpio_desc *powerdown_gpio;
>  };
>  
>  static int lvds_encoder_attach(struct drm_bridge *bridge)
> @@ -28,8 +30,30 @@ static int lvds_encoder_attach(struct drm_bridge *bridge)
>bridge);
>  }
>  
> +static void lvds_encoder_enable(struct drm_bridge *bridge)
> +{
> + struct lvds_encoder *lvds_encoder = container_of(bridge,
> +  struct lvds_encoder,
> +  bridge);
> +
> + if (lvds_encoder->powerdown_gpio)
> + gpiod_set_value_cansleep(lvds_encoder->powerdown_gpio, 0);

gpiod_set_value_cansleep() already contains a NULL check, so you can
drop it from here.

> +}
> +
> +static void lvds_encoder_disable(struct drm_bridge *bridge)
> +{
> + struct lvds_encoder *lvds_encoder = container_of(bridge,
> +  struct lvds_encoder,
> +  bridge);
> +
> + if (lvds_encoder->powerdown_gpio)
> + gpiod_set_value_cansleep(lvds_encoder->powerdown_gpio, 1);

Same here.

> +}
> +
>  static struct drm_bridge_funcs funcs = {

While at it, could you make this const ?

With these fixed,

Reviewed-by: Laurent Pinchart 

>   .attach = lvds_encoder_attach,
> + .enable = lvds_encoder_enable,
> + .disable = lvds_encoder_disable,
>  };
>  
>  static int lvds_encoder_probe(struct platform_device *pdev)
> @@ -45,6 +69,16 @@ static int lvds_encoder_probe(struct platform_device *pdev)
>   if (!lvds_encoder)
>   return -ENOMEM;
>  
> + lvds_encoder->powerdown_gpio = devm_gpiod_get_optional(dev, "powerdown",
> +GPIOD_OUT_HIGH);
> + if (IS_ERR(lvds_encoder->powerdown_gpio)) {
> + int err = PTR_ERR(lvds_encoder->powerdown_gpio);
> +
> + if (err != -EPROBE_DEFER)
> + dev_err(dev, "powerdown GPIO failure: %d\n", err);
> + return err;
> + }
> +
>   /* Locate the panel DT node. */
>   port = of_graph_get_port_by_id(dev->of_node, 1);
>   if (!port) {

-- 
Regards,

Laurent Pinchart


[PATCH v3 5/5] drm/bridge: lvds-encoder: add powerdown-gpios support

2018-12-28 Thread Peter Rosin
Optionally power down the LVDS-encoder when it is not in use.

Signed-off-by: Peter Rosin 
---
 drivers/gpu/drm/bridge/lvds-encoder.c | 34 ++
 1 file changed, 34 insertions(+)

diff --git a/drivers/gpu/drm/bridge/lvds-encoder.c 
b/drivers/gpu/drm/bridge/lvds-encoder.c
index f6770e83d49d..36d8557bc097 100644
--- a/drivers/gpu/drm/bridge/lvds-encoder.c
+++ b/drivers/gpu/drm/bridge/lvds-encoder.c
@@ -11,11 +11,13 @@
 #include 
 #include 
 
+#include 
 #include 
 
 struct lvds_encoder {
struct drm_bridge bridge;
struct drm_bridge *panel_bridge;
+   struct gpio_desc *powerdown_gpio;
 };
 
 static int lvds_encoder_attach(struct drm_bridge *bridge)
@@ -28,8 +30,30 @@ static int lvds_encoder_attach(struct drm_bridge *bridge)
 bridge);
 }
 
+static void lvds_encoder_enable(struct drm_bridge *bridge)
+{
+   struct lvds_encoder *lvds_encoder = container_of(bridge,
+struct lvds_encoder,
+bridge);
+
+   if (lvds_encoder->powerdown_gpio)
+   gpiod_set_value_cansleep(lvds_encoder->powerdown_gpio, 0);
+}
+
+static void lvds_encoder_disable(struct drm_bridge *bridge)
+{
+   struct lvds_encoder *lvds_encoder = container_of(bridge,
+struct lvds_encoder,
+bridge);
+
+   if (lvds_encoder->powerdown_gpio)
+   gpiod_set_value_cansleep(lvds_encoder->powerdown_gpio, 1);
+}
+
 static struct drm_bridge_funcs funcs = {
.attach = lvds_encoder_attach,
+   .enable = lvds_encoder_enable,
+   .disable = lvds_encoder_disable,
 };
 
 static int lvds_encoder_probe(struct platform_device *pdev)
@@ -45,6 +69,16 @@ static int lvds_encoder_probe(struct platform_device *pdev)
if (!lvds_encoder)
return -ENOMEM;
 
+   lvds_encoder->powerdown_gpio = devm_gpiod_get_optional(dev, "powerdown",
+  GPIOD_OUT_HIGH);
+   if (IS_ERR(lvds_encoder->powerdown_gpio)) {
+   int err = PTR_ERR(lvds_encoder->powerdown_gpio);
+
+   if (err != -EPROBE_DEFER)
+   dev_err(dev, "powerdown GPIO failure: %d\n", err);
+   return err;
+   }
+
/* Locate the panel DT node. */
port = of_graph_get_port_by_id(dev->of_node, 1);
if (!port) {
-- 
2.11.0