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