From c7d80059b086c4986cd994a1973ec7a5d75f8eea Mon Sep 17 00:00:00 2001 From: Jean-Jacques Hiblot Date: Fri, 28 Jul 2023 17:37:29 +0200 Subject: [PATCH] leds: class: Store the color index in struct led_classdev Store the color of the LED so that it is not lost after the LED's name has been composed. This color information can then be exposed to the user space or used by the LED consumer. Signed-off-by: Jean-Jacques Hiblot Link: https://lore.kernel.org/r/20230728153731.3742339-3-jjhiblot@traphandler.com Signed-off-by: Lee Jones --- Documentation/ABI/testing/sysfs-class-led | 9 +++++++++ drivers/leds/led-class.c | 21 +++++++++++++++++++++ include/linux/leds.h | 1 + 3 files changed, 31 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-class-led b/Documentation/ABI/testing/sysfs-class-led index 2e24ac3bd7efa..b2ff0012c0f2b 100644 --- a/Documentation/ABI/testing/sysfs-class-led +++ b/Documentation/ABI/testing/sysfs-class-led @@ -59,6 +59,15 @@ Description: brightness. Reading this file when no hw brightness change event has happened will return an ENODATA error. +What: /sys/class/leds//color +Date: June 2023 +KernelVersion: 6.5 +Description: + Color of the LED. + + This is a read-only file. Reading this file returns the color + of the LED as a string (e.g: "red", "green", "multicolor"). + What: /sys/class/leds//trigger Date: March 2006 KernelVersion: 2.6.17 diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c index 78068b06d009a..4bcbd46ec75a0 100644 --- a/drivers/leds/led-class.c +++ b/drivers/leds/led-class.c @@ -76,6 +76,19 @@ static ssize_t max_brightness_show(struct device *dev, } static DEVICE_ATTR_RO(max_brightness); +static ssize_t color_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + const char *color_text = "invalid"; + struct led_classdev *led_cdev = dev_get_drvdata(dev); + + if (led_cdev->color < LED_COLOR_ID_MAX) + color_text = led_colors[led_cdev->color]; + + return sysfs_emit(buf, "%s\n", color_text); +} +static DEVICE_ATTR_RO(color); + #ifdef CONFIG_LEDS_TRIGGERS static BIN_ATTR(trigger, 0644, led_trigger_read, led_trigger_write, 0); static struct bin_attribute *led_trigger_bin_attrs[] = { @@ -90,6 +103,7 @@ static const struct attribute_group led_trigger_group = { static struct attribute *led_class_attrs[] = { &dev_attr_brightness.attr, &dev_attr_max_brightness.attr, + &dev_attr_color.attr, NULL, }; @@ -486,6 +500,10 @@ int led_classdev_register_ext(struct device *parent, fwnode_property_read_u32(init_data->fwnode, "max-brightness", &led_cdev->max_brightness); + + if (fwnode_property_present(init_data->fwnode, "color")) + fwnode_property_read_u32(init_data->fwnode, "color", + &led_cdev->color); } } else { proposed_name = led_cdev->name; @@ -495,6 +513,9 @@ int led_classdev_register_ext(struct device *parent, if (ret < 0) return ret; + if (led_cdev->color >= LED_COLOR_ID_MAX) + dev_warn(parent, "LED %s color identifier out of range\n", final_name); + mutex_init(&led_cdev->led_access); mutex_lock(&led_cdev->led_access); led_cdev->dev = device_create_with_groups(leds_class, parent, 0, diff --git a/include/linux/leds.h b/include/linux/leds.h index 8740b4e47f889..aa16dc2a8230f 100644 --- a/include/linux/leds.h +++ b/include/linux/leds.h @@ -100,6 +100,7 @@ struct led_classdev { const char *name; unsigned int brightness; unsigned int max_brightness; + unsigned int color; int flags; /* Lower 16 bits reflect status */ -- 2.30.2