leds: multicolor: Introduce a multicolor class definition

Introduce a multicolor class that groups colored LEDs
within a LED node.

The multicolor class groups monochrome LEDs and allows controlling two
aspects of the final combined color: hue and lightness. The former is
controlled via the intensity file and the latter is controlled
via brightness file.

Signed-off-by: Dan Murphy <dmurphy@ti.com>
Acked-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
[squashed leds: multicolor: Fix camel case in documentation in]

1 files changed, 121 insertions, 0 deletions

diff --git a/include/linux/led-class-multicolor.h b/include/linux/led-class-multicolor.h
new file mode 100644
index 000000000000..5116f9a866cc
--- /dev/null
+++ b/include/linux/led-class-multicolor.h
@@ -0,0 +1,121 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* LED Multicolor class interface
+ * Copyright (C) 2019-20 Texas Instruments Incorporated - http://www.ti.com/
+ */
+
+#ifndef _LINUX_MULTICOLOR_LEDS_H_INCLUDED
+#define _LINUX_MULTICOLOR_LEDS_H_INCLUDED
+
+#include <linux/leds.h>
+#include <dt-bindings/leds/common.h>
+
+struct mc_subled {
+	unsigned int color_index;
+	unsigned int brightness;
+	unsigned int intensity;
+	unsigned int channel;
+};
+
+struct led_classdev_mc {
+	/* led class device */
+	struct led_classdev led_cdev;
+	unsigned int num_colors;
+
+	struct mc_subled *subled_info;
+};
+
+static inline struct led_classdev_mc *lcdev_to_mccdev(
+						struct led_classdev *led_cdev)
+{
+	return container_of(led_cdev, struct led_classdev_mc, led_cdev);
+}
+
+#if IS_ENABLED(CONFIG_LEDS_CLASS_MULTICOLOR)
+/**
+ * led_classdev_multicolor_register_ext - register a new object of led_classdev
+ *				      class with support for multicolor LEDs
+ * @parent: the multicolor LED to register
+ * @mcled_cdev: the led_classdev_mc structure for this device
+ * @init_data: the LED class multicolor device initialization data
+ *
+ * Returns: 0 on success or negative error value on failure
+ */
+int led_classdev_multicolor_register_ext(struct device *parent,
+					    struct led_classdev_mc *mcled_cdev,
+					    struct led_init_data *init_data);
+
+static inline int led_classdev_multicolor_register(struct device *parent,
+					    struct led_classdev_mc *mcled_cdev)
+{
+	return led_classdev_multicolor_register_ext(parent, mcled_cdev, NULL);
+}
+
+/**
+ * led_classdev_multicolor_unregister - unregisters an object of led_classdev
+ *					class with support for multicolor LEDs
+ * @mcled_cdev: the multicolor LED to unregister
+ *
+ * Unregister a previously registered via led_classdev_multicolor_register
+ * object
+ */
+void led_classdev_multicolor_unregister(struct led_classdev_mc *mcled_cdev);
+
+/* Calculate brightness for the monochrome LED cluster */
+int led_mc_calc_color_components(struct led_classdev_mc *mcled_cdev,
+				 enum led_brightness brightness);
+
+int devm_led_classdev_multicolor_register_ext(struct device *parent,
+					  struct led_classdev_mc *mcled_cdev,
+					  struct led_init_data *init_data);
+
+static inline int devm_led_classdev_multicolor_register(struct device *parent,
+				     struct led_classdev_mc *mcled_cdev)
+{
+	return devm_led_classdev_multicolor_register_ext(parent, mcled_cdev,
+							 NULL);
+}
+
+void devm_led_classdev_multicolor_unregister(struct device *parent,
+					    struct led_classdev_mc *mcled_cdev);
+#else
+
+static inline int led_classdev_multicolor_register_ext(struct device *parent,
+					    struct led_classdev_mc *mcled_cdev,
+					    struct led_init_data *init_data)
+{
+	return -EINVAL;
+}
+
+static inline int led_classdev_multicolor_register(struct device *parent,
+					    struct led_classdev_mc *mcled_cdev)
+{
+	return led_classdev_multicolor_register_ext(parent, mcled_cdev, NULL);
+}
+
+static inline void led_classdev_multicolor_unregister(struct led_classdev_mc *mcled_cdev) {};
+static inline int led_mc_calc_color_components(struct led_classdev_mc *mcled_cdev,
+					       enum led_brightness brightness)
+{
+	return -EINVAL;
+}
+
+static inline int devm_led_classdev_multicolor_register_ext(struct device *parent,
+					  struct led_classdev_mc *mcled_cdev,
+					  struct led_init_data *init_data)
+{
+	return -EINVAL;
+}
+
+static inline int devm_led_classdev_multicolor_register(struct device *parent,
+					     struct led_classdev_mc *mcled_cdev)
+{
+	return devm_led_classdev_multicolor_register_ext(parent, mcled_cdev,
+							 NULL);
+}
+
+static inline void devm_led_classdev_multicolor_unregister(struct device *parent,
+					    struct led_classdev_mc *mcled_cdev)
+{};
+
+#endif  /* IS_ENABLED(CONFIG_LEDS_CLASS_MULTICOLOR) */
+#endif	/* _LINUX_MULTICOLOR_LEDS_H_INCLUDED */