By allowing to group multiple monochrome LED into multicolor LEDs,
all involved LEDs can be controlled in-sync. This enables using effects
using triggers, etc.
Signed-off-by: Jean-Jacques Hiblot <jjhiblot@xxxxxxxxxxxxxxx>
---
drivers/leds/rgb/Kconfig | 7 +
drivers/leds/rgb/Makefile | 1 +
drivers/leds/rgb/leds-group-multicolor.c | 177 +++++++++++++++++++++++
3 files changed, 185 insertions(+)
create mode 100644 drivers/leds/rgb/leds-group-multicolor.c
diff --git a/drivers/leds/rgb/Kconfig b/drivers/leds/rgb/Kconfig
index 204cf470beae..b50790385561 100644
--- a/drivers/leds/rgb/Kconfig
+++ b/drivers/leds/rgb/Kconfig
@@ -2,6 +2,13 @@
if LEDS_CLASS_MULTICOLOR
+config LEDS_GRP_MULTICOLOR
+ tristate "multi-color LED grouping Support"
+ depends on PWM
+ help
+ This option enables support for monochrome LEDs that are
+ grouped into multicolor LEDs.
+
config LEDS_PWM_MULTICOLOR
tristate "PWM driven multi-color LED Support"
depends on PWM
diff --git a/drivers/leds/rgb/Makefile b/drivers/leds/rgb/Makefile
index 0675bc0f6e18..4de087ad79bc 100644
--- a/drivers/leds/rgb/Makefile
+++ b/drivers/leds/rgb/Makefile
@@ -1,4 +1,5 @@
# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_LEDS_GRP_MULTICOLOR) += leds-group-multicolor.o
obj-$(CONFIG_LEDS_PWM_MULTICOLOR) += leds-pwm-multicolor.o
obj-$(CONFIG_LEDS_QCOM_LPG) += leds-qcom-lpg.o
diff --git a/drivers/leds/rgb/leds-group-multicolor.c b/drivers/leds/rgb/leds-group-multicolor.c
new file mode 100644
index 000000000000..872854aed6eb
--- /dev/null
+++ b/drivers/leds/rgb/leds-group-multicolor.c
@@ -0,0 +1,177 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * multi-color LED built with monochromatic LED devices
+ *
+ * This driver is derived from the leds-pwm-multicolor driver
+ *
+ * Copyright 2022 Jean-Jacques Hiblot <jjhiblot@xxxxxxxxxxxxxxx>
+ */
+
+#include <linux/err.h>
+#include <linux/led-class-multicolor.h>
+#include <linux/leds.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+
+struct led_mcg_priv {
+ struct led_classdev_mc mc_cdev;
+ struct led_classdev *monochromatics[];
+};
+
+static int led_mcg_set(struct led_classdev *cdev,
+ enum led_brightness brightness)
+{
+ struct led_classdev_mc *mc_cdev = lcdev_to_mccdev(cdev);
+ struct led_mcg_priv *priv =
+ container_of(mc_cdev, struct led_mcg_priv, mc_cdev);
+ int i;
+
+ led_mc_calc_color_components(mc_cdev, brightness);
+
+ for (i = 0; i < mc_cdev->num_colors; i++) {
+ struct led_classdev *mono = priv->monochromatics[i];
+ int actual_led_brightness;
+
+ /*
+ * Scale the intensity according the max brightness of the
+ * monochromatic LED
+ */
+ actual_led_brightness = DIV_ROUND_CLOSEST(
+ mono->max_brightness * mc_cdev->subled_info[i].brightness,
+ mc_cdev->led_cdev.max_brightness);
+
+ led_set_brightness(mono, actual_led_brightness);
+ }
+ return 0;
+}
+
+static int iterate_subleds(struct device *dev, struct led_mcg_priv *priv,
+ struct fwnode_handle *mcnode)
+{
+ struct mc_subled *subled = priv->mc_cdev.subled_info;
+ struct fwnode_handle *fwnode;
+ int ret;
+
+ /* iterate over the nodes inside the multi-led node */
+ fwnode_for_each_child_node(mcnode, fwnode) {
+ u32 color;
+ struct led_classdev *led_cdev;
+
+ led_cdev = devm_fwnode_led_get(dev, fwnode, 0);
+ if (IS_ERR(led_cdev)) {
+ ret = PTR_ERR(led_cdev);
+ dev_err(dev, "unable to request LED: %d\n", ret);
+ goto release_fwnode;
+ }
+ priv->monochromatics[priv->mc_cdev.num_colors] = led_cdev;
+
+ ret = fwnode_property_read_u32(fwnode, "color", &color);
+ if (ret) {
+ dev_err(dev, "cannot read color: %d\n", ret);
+ goto release_fwnode;
+ }
+ subled[priv->mc_cdev.num_colors].color_index = color;
+
+ /* Make the sysfs of the monochromatic LED read-only */
+ led_cdev->flags |= LED_SYSFS_DISABLE;
+
+ priv->mc_cdev.num_colors++;
+ }
+
+ return 0;
+
+release_fwnode:
+ fwnode_handle_put(fwnode);
+ return ret;
+}
+
+static int led_mcg_probe(struct platform_device *pdev)
+{
+ struct fwnode_handle *mcnode, *fwnode;
+ struct led_init_data init_data = {};
+ struct led_classdev *cdev;
+ struct mc_subled *subled;
+ struct led_mcg_priv *priv;
+ int count = 0;
+ int ret = 0;
+
+ mcnode = device_get_named_child_node(&pdev->dev, "multi-led");
+ if (!mcnode)
+ return dev_err_probe(&pdev->dev, -ENODEV,
+ "expected multi-led node\n");
+
+ /* count the nodes inside the multi-led node */
+ fwnode_for_each_child_node(mcnode, fwnode)
+ count++;
+
+ priv = devm_kzalloc(&pdev->dev,
+ struct_size(priv, monochromatics, count),
+ GFP_KERNEL);
+ if (!priv) {
+ ret = -ENOMEM;
+ goto release_mcnode;
+ }
+
+ subled = devm_kcalloc(&pdev->dev, count, sizeof(*subled), GFP_KERNEL);
+ if (!subled) {
+ ret = -ENOMEM;
+ goto release_mcnode;
+ }
+ priv->mc_cdev.subled_info = subled;
+
+ /* init the multicolor's LED class device */
+ cdev = &priv->mc_cdev.led_cdev;
+ fwnode_property_read_u32(mcnode, "max-brightness",
+ &cdev->max_brightness);
+ cdev->flags = LED_CORE_SUSPENDRESUME;
+ cdev->brightness_set_blocking = led_mcg_set;
+
+ ret = iterate_subleds(&pdev->dev, priv, mcnode);
+ if (ret)
+ goto release_mcnode;
+
+ init_data.fwnode = mcnode;
+ ret = devm_led_classdev_multicolor_register_ext(&pdev->dev,
+ &priv->mc_cdev,
+ &init_data);
+ if (ret) {
+ dev_err(&pdev->dev,
+ "failed to register multicolor led for %s: %d\n",
+ cdev->name, ret);
+ goto release_mcnode;
+ }
+
+ ret = led_mcg_set(cdev, cdev->brightness);
+ if (ret)
+ return dev_err_probe(&pdev->dev, ret,
+ "failed to set led value for %s: %d",
+ cdev->name, ret);
+
+ return 0;
+
+release_mcnode:
+ fwnode_handle_put(mcnode);
+ return ret;
+}
+
+static const struct of_device_id of_led_mcg_match[] = {
+ { .compatible = "leds-group-multicolor" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, of_led_mcg_match);
+
+static struct platform_driver led_mcg_driver = {
+ .probe = led_mcg_probe,
+ .driver = {
+ .name = "leds_group_multicolor",
+ .of_match_table = of_led_mcg_match,
+ }
+};
+module_platform_driver(led_mcg_driver);
+
+MODULE_AUTHOR("Jean-Jacques Hiblot <jjhiblot@xxxxxxxxxxxxxxx>");
+MODULE_DESCRIPTION("multi-color LED group driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:leds-group-multicolor");
--
2.25.1
