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authorDan Murphy <dmurphy@ti.com>2020-07-16 21:19:56 +0300
committerPavel Machek <pavel@ucw.cz>2020-07-22 15:41:29 +0300
commit55d5d3b46b08a4dc0b05343d24640744e7430ed7 (patch)
treef201e4248416a591ea17c23cc2110e75efcab153 /drivers/leds
parent10d3e0d815879129e916cd83e1034438e06efdaa (diff)
downloadlinux-55d5d3b46b08a4dc0b05343d24640744e7430ed7.tar.xz
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]
Diffstat (limited to 'drivers/leds')
-rw-r--r--drivers/leds/Kconfig10
-rw-r--r--drivers/leds/Makefile1
-rw-r--r--drivers/leds/led-class-multicolor.c203
3 files changed, 214 insertions, 0 deletions
diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index ed943140e1fd..1de6e8e264a0 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -30,6 +30,16 @@ config LEDS_CLASS_FLASH
for the flash related features of a LED device. It can be built
as a module.
+config LEDS_CLASS_MULTICOLOR
+ tristate "LED Multicolor Class Support"
+ depends on LEDS_CLASS
+ help
+ This option enables the multicolor LED sysfs class in /sys/class/leds.
+ It wraps LED class and adds multicolor LED specific sysfs attributes
+ and kernel internal API to it. You'll need this to provide support
+ for multicolor LEDs that are grouped together. This class is not
+ intended for single color LEDs. It can be built as a module.
+
config LEDS_BRIGHTNESS_HW_CHANGED
bool "LED Class brightness_hw_changed attribute support"
depends on LEDS_CLASS
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index d6b8a792c936..d684bc76d2b2 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -4,6 +4,7 @@
obj-$(CONFIG_NEW_LEDS) += led-core.o
obj-$(CONFIG_LEDS_CLASS) += led-class.o
obj-$(CONFIG_LEDS_CLASS_FLASH) += led-class-flash.o
+obj-$(CONFIG_LEDS_CLASS_MULTICOLOR) += led-class-multicolor.o
obj-$(CONFIG_LEDS_TRIGGERS) += led-triggers.o
# LED Platform Drivers (keep this sorted, M-| sort)
diff --git a/drivers/leds/led-class-multicolor.c b/drivers/leds/led-class-multicolor.c
new file mode 100644
index 000000000000..e317408583df
--- /dev/null
+++ b/drivers/leds/led-class-multicolor.c
@@ -0,0 +1,203 @@
+// SPDX-License-Identifier: GPL-2.0
+// LED Multicolor class interface
+// Copyright (C) 2019-20 Texas Instruments Incorporated - http://www.ti.com/
+// Author: Dan Murphy <dmurphy@ti.com>
+
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/led-class-multicolor.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+
+#include "leds.h"
+
+int led_mc_calc_color_components(struct led_classdev_mc *mcled_cdev,
+ enum led_brightness brightness)
+{
+ struct led_classdev *led_cdev = &mcled_cdev->led_cdev;
+ int i;
+
+ for (i = 0; i < mcled_cdev->num_colors; i++)
+ mcled_cdev->subled_info[i].brightness = brightness *
+ mcled_cdev->subled_info[i].intensity /
+ led_cdev->max_brightness;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(led_mc_calc_color_components);
+
+static ssize_t multi_intensity_store(struct device *dev,
+ struct device_attribute *intensity_attr,
+ const char *buf, size_t size)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+ struct led_classdev_mc *mcled_cdev = lcdev_to_mccdev(led_cdev);
+ int nrchars, offset = 0;
+ int intensity_value[LED_COLOR_ID_MAX];
+ int i;
+ ssize_t ret;
+
+ mutex_lock(&led_cdev->led_access);
+
+ for (i = 0; i < mcled_cdev->num_colors; i++) {
+ ret = sscanf(buf + offset, "%i%n",
+ &intensity_value[i], &nrchars);
+ if (ret != 1) {
+ ret = -EINVAL;
+ goto err_out;
+ }
+ offset += nrchars;
+ }
+
+ offset++;
+ if (offset < size) {
+ ret = -EINVAL;
+ goto err_out;
+ }
+
+ for (i = 0; i < mcled_cdev->num_colors; i++)
+ mcled_cdev->subled_info[i].intensity = intensity_value[i];
+
+ led_set_brightness(led_cdev, led_cdev->brightness);
+ ret = size;
+err_out:
+ mutex_unlock(&led_cdev->led_access);
+ return ret;
+}
+
+static ssize_t multi_intensity_show(struct device *dev,
+ struct device_attribute *intensity_attr,
+ char *buf)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+ struct led_classdev_mc *mcled_cdev = lcdev_to_mccdev(led_cdev);
+ int len = 0;
+ int i;
+
+ for (i = 0; i < mcled_cdev->num_colors; i++) {
+ len += sprintf(buf + len, "%d",
+ mcled_cdev->subled_info[i].intensity);
+ if (i < mcled_cdev->num_colors - 1)
+ len += sprintf(buf + len, " ");
+ }
+
+ buf[len++] = '\n';
+ return len;
+}
+static DEVICE_ATTR_RW(multi_intensity);
+
+static ssize_t multi_index_show(struct device *dev,
+ struct device_attribute *multi_index_attr,
+ char *buf)
+{
+ struct led_classdev *led_cdev = dev_get_drvdata(dev);
+ struct led_classdev_mc *mcled_cdev = lcdev_to_mccdev(led_cdev);
+ int len = 0;
+ int index;
+ int i;
+
+ for (i = 0; i < mcled_cdev->num_colors; i++) {
+ index = mcled_cdev->subled_info[i].color_index;
+ len += sprintf(buf + len, "%s", led_colors[index]);
+ if (i < mcled_cdev->num_colors - 1)
+ len += sprintf(buf + len, " ");
+ }
+
+ buf[len++] = '\n';
+ return len;
+}
+static DEVICE_ATTR_RO(multi_index);
+
+static struct attribute *led_multicolor_attrs[] = {
+ &dev_attr_multi_intensity.attr,
+ &dev_attr_multi_index.attr,
+ NULL,
+};
+ATTRIBUTE_GROUPS(led_multicolor);
+
+int led_classdev_multicolor_register_ext(struct device *parent,
+ struct led_classdev_mc *mcled_cdev,
+ struct led_init_data *init_data)
+{
+ struct led_classdev *led_cdev;
+
+ if (!mcled_cdev)
+ return -EINVAL;
+
+ if (mcled_cdev->num_colors <= 0)
+ return -EINVAL;
+
+ if (mcled_cdev->num_colors > LED_COLOR_ID_MAX)
+ return -EINVAL;
+
+ led_cdev = &mcled_cdev->led_cdev;
+ mcled_cdev->led_cdev.groups = led_multicolor_groups;
+
+ return led_classdev_register_ext(parent, led_cdev, init_data);
+}
+EXPORT_SYMBOL_GPL(led_classdev_multicolor_register_ext);
+
+void led_classdev_multicolor_unregister(struct led_classdev_mc *mcled_cdev)
+{
+ if (!mcled_cdev)
+ return;
+
+ led_classdev_unregister(&mcled_cdev->led_cdev);
+}
+EXPORT_SYMBOL_GPL(led_classdev_multicolor_unregister);
+
+static void devm_led_classdev_multicolor_release(struct device *dev, void *res)
+{
+ led_classdev_multicolor_unregister(*(struct led_classdev_mc **)res);
+}
+
+int devm_led_classdev_multicolor_register_ext(struct device *parent,
+ struct led_classdev_mc *mcled_cdev,
+ struct led_init_data *init_data)
+{
+ struct led_classdev_mc **dr;
+ int ret;
+
+ dr = devres_alloc(devm_led_classdev_multicolor_release,
+ sizeof(*dr), GFP_KERNEL);
+ if (!dr)
+ return -ENOMEM;
+
+ ret = led_classdev_multicolor_register_ext(parent, mcled_cdev,
+ init_data);
+ if (ret) {
+ devres_free(dr);
+ return ret;
+ }
+
+ *dr = mcled_cdev;
+ devres_add(parent, dr);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(devm_led_classdev_multicolor_register_ext);
+
+static int devm_led_classdev_multicolor_match(struct device *dev,
+ void *res, void *data)
+{
+ struct led_classdev_mc **p = res;
+
+ if (WARN_ON(!p || !*p))
+ return 0;
+
+ return *p == data;
+}
+
+void devm_led_classdev_multicolor_unregister(struct device *dev,
+ struct led_classdev_mc *mcled_cdev)
+{
+ WARN_ON(devres_release(dev,
+ devm_led_classdev_multicolor_release,
+ devm_led_classdev_multicolor_match, mcled_cdev));
+}
+EXPORT_SYMBOL_GPL(devm_led_classdev_multicolor_unregister);
+
+MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
+MODULE_DESCRIPTION("Multicolor LED class interface");
+MODULE_LICENSE("GPL v2");