dm: Add support for LEDs

Add a simple uclass for LEDs, so that these can be controlled by the device
tree and activated when needed. LEDs are referred to by their label.

This implementation requires a driver for each type of LED (e.g GPIO, I2C).

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

1 files changed, 51 insertions, 0 deletions

diff --git a/include/led.h b/include/led.h
new file mode 100644
index 0000000..8925d75
--- /dev/null
+++ b/include/led.h
@@ -0,0 +1,51 @@
+/*
+ * Copyright (c) 2015 Google, Inc
+ * Written by Simon Glass <sjg@chromium.org>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#ifndef __LED_H
+#define __LED_H
+
+/**
+ * struct led_uclass_plat - Platform data the uclass stores about each device
+ *
+ * @label:	LED label
+ */
+struct led_uclass_plat {
+	const char *label;
+};
+
+struct led_ops {
+	/**
+	 * set_on() - set the state of an LED
+	 *
+	 * @dev:	LED device to change
+	 * @on:		1 to turn the LED on, 0 to turn it off
+	 * @return 0 if OK, -ve on error
+	 */
+	int (*set_on)(struct udevice *dev, int on);
+};
+
+#define led_get_ops(dev)	((struct led_ops *)(dev)->driver->ops)
+
+/**
+ * led_get_by_label() - Find an LED device by label
+ *
+ * @label:	LED label to look up
+ * @devp:	Returns the associated device, if found
+ * @return 0 if found, -ve on error
+ */
+int led_get_by_label(const char *label, struct udevice **devp);
+
+/**
+ * led_set_on() - set the state of an LED
+ *
+ * @dev:	LED device to change
+ * @on:		1 to turn the LED on, 0 to turn it off
+ * @return 0 if OK, -ve on error
+ */
+int led_set_on(struct udevice *dev, int on);
+
+#endif