drm/panel: seiko-43wvf1g: Add the 'enable-gpios' property

Sometimes a GPIO is needed to turn on/off the display.

Add support for this usecase by introducing the optional 'enable-gpios'
property.

Tested on a imx53qsb board.

Signed-off-by: Fabio Estevam <festevam@denx.de>
Reviewed-by: Neil Armstrong <neil.armstrong@linaro.org>
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230314111724.1520178-2-festevam@denx.de

diff --git a/drivers/gpu/drm/panel/panel-seiko-43wvf1g.c b/drivers/gpu/drm/panel/panel-seiko-43wvf1g.c
index 76160e5..c250ca3 100644 (file)
--- a/drivers/gpu/drm/panel/panel-seiko-43wvf1g.c
+++ b/drivers/gpu/drm/panel/panel-seiko-43wvf1g.c
@@ -7,6 +7,7 @@
  */
 
 #include <linux/delay.h>
+#include <linux/gpio/consumer.h>
 #include <linux/media-bus-format.h>
 #include <linux/module.h>
 #include <linux/of.h>
@@ -48,6 +49,7 @@ struct seiko_panel {
        const struct seiko_panel_desc *desc;
        struct regulator *dvdd;
        struct regulator *avdd;
+       struct gpio_desc *enable_gpio;
 };
 
 static inline struct seiko_panel *to_seiko_panel(struct drm_panel *panel)
@@ -139,6 +141,8 @@ static int seiko_panel_unprepare(struct drm_panel *panel)
        if (!p->prepared)
                return 0;
 
+       gpiod_set_value_cansleep(p->enable_gpio, 0);
+
        regulator_disable(p->avdd);
 
        /* Add a 100ms delay as per the panel datasheet */
@@ -174,6 +178,8 @@ static int seiko_panel_prepare(struct drm_panel *panel)
                goto disable_dvdd;
        }
 
+       gpiod_set_value_cansleep(p->enable_gpio, 1);
+
        p->prepared = true;
 
        return 0;
@@ -252,6 +258,12 @@ static int seiko_panel_probe(struct device *dev,
        if (IS_ERR(panel->avdd))
                return PTR_ERR(panel->avdd);
 
+       panel->enable_gpio = devm_gpiod_get_optional(dev, "enable",
+                                                    GPIOD_OUT_LOW);
+       if (IS_ERR(panel->enable_gpio))
+               return dev_err_probe(dev, PTR_ERR(panel->enable_gpio),
+                                    "failed to request GPIO\n");
+
        drm_panel_init(&panel->base, dev, &seiko_panel_funcs,
                       DRM_MODE_CONNECTOR_DPI);