video: panel: Add a simple panel driver

Most panels are very simple - they just have a power supply and a backlight.
Add a driver which supports this and implements the enable_backlight()
method.

Signed-off-by: Simon Glass <sjg@chromium.org>

diff --git a/drivers/video/Makefile b/drivers/video/Makefile
index d29280c..6658e96 100644 (file)
--- a/drivers/video/Makefile
+++ b/drivers/video/Makefile
@@ -8,7 +8,7 @@
 ifdef CONFIG_DM
 obj-$(CONFIG_DISPLAY_PORT) += dp-uclass.o
 obj-$(CONFIG_DM_VIDEO) += backlight-uclass.o
-obj-$(CONFIG_DM_VIDEO) += panel-uclass.o
+obj-$(CONFIG_DM_VIDEO) += panel-uclass.o simple_panel.o
 obj-$(CONFIG_DM_VIDEO) += video-uclass.o vidconsole-uclass.o console_normal.o
 obj-$(CONFIG_DM_VIDEO) += video_bmp.o
 ifdef CONFIG_DM_VIDEO

diff --git a/drivers/video/simple_panel.c b/drivers/video/simple_panel.c
new file mode 100644 (file)
index 0000000..b161517
--- /dev/null
+++ b/drivers/video/simple_panel.c
@@ -0,0 +1,99 @@
+/*
+ * Copyright (c) 2016 Google, Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ *
+ * SPDX-License-Identifier:    GPL-2.0+
+ */
+
+#include <common.h>
+#include <backlight.h>
+#include <dm.h>
+#include <panel.h>
+#include <asm/gpio.h>
+#include <power/regulator.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+struct simple_panel_priv {
+       struct udevice *reg;
+       struct udevice *backlight;
+       struct gpio_desc enable;
+};
+
+static int simple_panel_enable_backlight(struct udevice *dev)
+{
+       struct simple_panel_priv *priv = dev_get_priv(dev);
+       int ret;
+
+       dm_gpio_set_value(&priv->enable, 1);
+       ret = backlight_enable(priv->backlight);
+       if (ret)
+               return ret;
+
+       return 0;
+}
+
+static int simple_panel_ofdata_to_platdata(struct udevice *dev)
+{
+       struct simple_panel_priv *priv = dev_get_priv(dev);
+       int ret;
+
+       ret = uclass_get_device_by_phandle(UCLASS_REGULATOR, dev,
+                                          "power-supply", &priv->reg);
+       if (ret) {
+               debug("%s: Warning: cnnot get power supply: ret=%d\n",
+                     __func__, ret);
+               if (ret != -ENOENT)
+                       return ret;
+       }
+       ret = uclass_get_device_by_phandle(UCLASS_PANEL_BACKLIGHT, dev,
+                                          "backlight", &priv->backlight);
+       if (ret) {
+               debug("%s: Cannot get backlight: ret=%d\n", __func__, ret);
+               return ret;
+       }
+       ret = gpio_request_by_name(dev, "enable-gpios", 0, &priv->enable,
+                                  GPIOD_IS_OUT);
+       if (ret) {
+               debug("%s: Warning: cannot get enable GPIO: ret=%d\n",
+                     __func__, ret);
+               if (ret != -ENOENT)
+                       return ret;
+       }
+
+       return 0;
+}
+
+static int simple_panel_probe(struct udevice *dev)
+{
+       struct simple_panel_priv *priv = dev_get_priv(dev);
+       int ret;
+
+       if (priv->reg) {
+               debug("%s: Enable regulator '%s'\n", __func__, priv->reg->name);
+               ret = regulator_set_enable(priv->reg, true);
+               if (ret)
+                       return ret;
+       }
+
+       return 0;
+}
+
+static const struct panel_ops simple_panel_ops = {
+       .enable_backlight       = simple_panel_enable_backlight,
+};
+
+static const struct udevice_id simple_panel_ids[] = {
+       { .compatible = "simple-panel" },
+       { }
+};
+
+U_BOOT_DRIVER(simple_panel) = {
+       .name   = "simple_panel",
+       .id     = UCLASS_PANEL,
+       .of_match = simple_panel_ids,
+       .ops    = &simple_panel_ops,
+       .ofdata_to_platdata     = simple_panel_ofdata_to_platdata,
+       .probe          = simple_panel_probe,
+       .priv_auto_alloc_size   = sizeof(struct simple_panel_priv),
+};