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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /drivers/leds/led-core.c
parentInitial commit. (diff)
downloadlinux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz
linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/leds/led-core.c')
-rw-r--r--drivers/leds/led-core.c485
1 files changed, 485 insertions, 0 deletions
diff --git a/drivers/leds/led-core.c b/drivers/leds/led-core.c
new file mode 100644
index 000000000..c4e780bdb
--- /dev/null
+++ b/drivers/leds/led-core.c
@@ -0,0 +1,485 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * LED Class Core
+ *
+ * Copyright 2005-2006 Openedhand Ltd.
+ *
+ * Author: Richard Purdie <rpurdie@openedhand.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/leds.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of.h>
+#include <linux/property.h>
+#include <linux/rwsem.h>
+#include <linux/slab.h>
+#include <uapi/linux/uleds.h>
+#include "leds.h"
+
+DECLARE_RWSEM(leds_list_lock);
+EXPORT_SYMBOL_GPL(leds_list_lock);
+
+LIST_HEAD(leds_list);
+EXPORT_SYMBOL_GPL(leds_list);
+
+const char * const led_colors[LED_COLOR_ID_MAX] = {
+ [LED_COLOR_ID_WHITE] = "white",
+ [LED_COLOR_ID_RED] = "red",
+ [LED_COLOR_ID_GREEN] = "green",
+ [LED_COLOR_ID_BLUE] = "blue",
+ [LED_COLOR_ID_AMBER] = "amber",
+ [LED_COLOR_ID_VIOLET] = "violet",
+ [LED_COLOR_ID_YELLOW] = "yellow",
+ [LED_COLOR_ID_IR] = "ir",
+ [LED_COLOR_ID_MULTI] = "multicolor",
+ [LED_COLOR_ID_RGB] = "rgb",
+};
+EXPORT_SYMBOL_GPL(led_colors);
+
+static int __led_set_brightness(struct led_classdev *led_cdev,
+ enum led_brightness value)
+{
+ if (!led_cdev->brightness_set)
+ return -ENOTSUPP;
+
+ led_cdev->brightness_set(led_cdev, value);
+
+ return 0;
+}
+
+static int __led_set_brightness_blocking(struct led_classdev *led_cdev,
+ enum led_brightness value)
+{
+ if (!led_cdev->brightness_set_blocking)
+ return -ENOTSUPP;
+
+ return led_cdev->brightness_set_blocking(led_cdev, value);
+}
+
+static void led_timer_function(struct timer_list *t)
+{
+ struct led_classdev *led_cdev = from_timer(led_cdev, t, blink_timer);
+ unsigned long brightness;
+ unsigned long delay;
+
+ if (!led_cdev->blink_delay_on || !led_cdev->blink_delay_off) {
+ led_set_brightness_nosleep(led_cdev, LED_OFF);
+ clear_bit(LED_BLINK_SW, &led_cdev->work_flags);
+ return;
+ }
+
+ if (test_and_clear_bit(LED_BLINK_ONESHOT_STOP,
+ &led_cdev->work_flags)) {
+ clear_bit(LED_BLINK_SW, &led_cdev->work_flags);
+ return;
+ }
+
+ brightness = led_get_brightness(led_cdev);
+ if (!brightness) {
+ /* Time to switch the LED on. */
+ if (test_and_clear_bit(LED_BLINK_BRIGHTNESS_CHANGE,
+ &led_cdev->work_flags))
+ brightness = led_cdev->new_blink_brightness;
+ else
+ brightness = led_cdev->blink_brightness;
+ delay = led_cdev->blink_delay_on;
+ } else {
+ /* Store the current brightness value to be able
+ * to restore it when the delay_off period is over.
+ */
+ led_cdev->blink_brightness = brightness;
+ brightness = LED_OFF;
+ delay = led_cdev->blink_delay_off;
+ }
+
+ led_set_brightness_nosleep(led_cdev, brightness);
+
+ /* Return in next iteration if led is in one-shot mode and we are in
+ * the final blink state so that the led is toggled each delay_on +
+ * delay_off milliseconds in worst case.
+ */
+ if (test_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags)) {
+ if (test_bit(LED_BLINK_INVERT, &led_cdev->work_flags)) {
+ if (brightness)
+ set_bit(LED_BLINK_ONESHOT_STOP,
+ &led_cdev->work_flags);
+ } else {
+ if (!brightness)
+ set_bit(LED_BLINK_ONESHOT_STOP,
+ &led_cdev->work_flags);
+ }
+ }
+
+ mod_timer(&led_cdev->blink_timer, jiffies + msecs_to_jiffies(delay));
+}
+
+static void set_brightness_delayed(struct work_struct *ws)
+{
+ struct led_classdev *led_cdev =
+ container_of(ws, struct led_classdev, set_brightness_work);
+ int ret = 0;
+
+ if (test_and_clear_bit(LED_BLINK_DISABLE, &led_cdev->work_flags)) {
+ led_cdev->delayed_set_value = LED_OFF;
+ led_stop_software_blink(led_cdev);
+ }
+
+ ret = __led_set_brightness(led_cdev, led_cdev->delayed_set_value);
+ if (ret == -ENOTSUPP)
+ ret = __led_set_brightness_blocking(led_cdev,
+ led_cdev->delayed_set_value);
+ if (ret < 0 &&
+ /* LED HW might have been unplugged, therefore don't warn */
+ !(ret == -ENODEV && (led_cdev->flags & LED_UNREGISTERING) &&
+ (led_cdev->flags & LED_HW_PLUGGABLE)))
+ dev_err(led_cdev->dev,
+ "Setting an LED's brightness failed (%d)\n", ret);
+}
+
+static void led_set_software_blink(struct led_classdev *led_cdev,
+ unsigned long delay_on,
+ unsigned long delay_off)
+{
+ int current_brightness;
+
+ current_brightness = led_get_brightness(led_cdev);
+ if (current_brightness)
+ led_cdev->blink_brightness = current_brightness;
+ if (!led_cdev->blink_brightness)
+ led_cdev->blink_brightness = led_cdev->max_brightness;
+
+ led_cdev->blink_delay_on = delay_on;
+ led_cdev->blink_delay_off = delay_off;
+
+ /* never on - just set to off */
+ if (!delay_on) {
+ led_set_brightness_nosleep(led_cdev, LED_OFF);
+ return;
+ }
+
+ /* never off - just set to brightness */
+ if (!delay_off) {
+ led_set_brightness_nosleep(led_cdev,
+ led_cdev->blink_brightness);
+ return;
+ }
+
+ set_bit(LED_BLINK_SW, &led_cdev->work_flags);
+ mod_timer(&led_cdev->blink_timer, jiffies + 1);
+}
+
+
+static void led_blink_setup(struct led_classdev *led_cdev,
+ unsigned long *delay_on,
+ unsigned long *delay_off)
+{
+ if (!test_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags) &&
+ led_cdev->blink_set &&
+ !led_cdev->blink_set(led_cdev, delay_on, delay_off))
+ return;
+
+ /* blink with 1 Hz as default if nothing specified */
+ if (!*delay_on && !*delay_off)
+ *delay_on = *delay_off = 500;
+
+ led_set_software_blink(led_cdev, *delay_on, *delay_off);
+}
+
+void led_init_core(struct led_classdev *led_cdev)
+{
+ INIT_WORK(&led_cdev->set_brightness_work, set_brightness_delayed);
+
+ timer_setup(&led_cdev->blink_timer, led_timer_function, 0);
+}
+EXPORT_SYMBOL_GPL(led_init_core);
+
+void led_blink_set(struct led_classdev *led_cdev,
+ unsigned long *delay_on,
+ unsigned long *delay_off)
+{
+ del_timer_sync(&led_cdev->blink_timer);
+
+ clear_bit(LED_BLINK_SW, &led_cdev->work_flags);
+ clear_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags);
+ clear_bit(LED_BLINK_ONESHOT_STOP, &led_cdev->work_flags);
+
+ led_blink_setup(led_cdev, delay_on, delay_off);
+}
+EXPORT_SYMBOL_GPL(led_blink_set);
+
+void led_blink_set_oneshot(struct led_classdev *led_cdev,
+ unsigned long *delay_on,
+ unsigned long *delay_off,
+ int invert)
+{
+ if (test_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags) &&
+ timer_pending(&led_cdev->blink_timer))
+ return;
+
+ set_bit(LED_BLINK_ONESHOT, &led_cdev->work_flags);
+ clear_bit(LED_BLINK_ONESHOT_STOP, &led_cdev->work_flags);
+
+ if (invert)
+ set_bit(LED_BLINK_INVERT, &led_cdev->work_flags);
+ else
+ clear_bit(LED_BLINK_INVERT, &led_cdev->work_flags);
+
+ led_blink_setup(led_cdev, delay_on, delay_off);
+}
+EXPORT_SYMBOL_GPL(led_blink_set_oneshot);
+
+void led_stop_software_blink(struct led_classdev *led_cdev)
+{
+ del_timer_sync(&led_cdev->blink_timer);
+ led_cdev->blink_delay_on = 0;
+ led_cdev->blink_delay_off = 0;
+ clear_bit(LED_BLINK_SW, &led_cdev->work_flags);
+}
+EXPORT_SYMBOL_GPL(led_stop_software_blink);
+
+void led_set_brightness(struct led_classdev *led_cdev,
+ enum led_brightness brightness)
+{
+ /*
+ * If software blink is active, delay brightness setting
+ * until the next timer tick.
+ */
+ if (test_bit(LED_BLINK_SW, &led_cdev->work_flags)) {
+ /*
+ * If we need to disable soft blinking delegate this to the
+ * work queue task to avoid problems in case we are called
+ * from hard irq context.
+ */
+ if (brightness == LED_OFF) {
+ set_bit(LED_BLINK_DISABLE, &led_cdev->work_flags);
+ schedule_work(&led_cdev->set_brightness_work);
+ } else {
+ set_bit(LED_BLINK_BRIGHTNESS_CHANGE,
+ &led_cdev->work_flags);
+ led_cdev->new_blink_brightness = brightness;
+ }
+ return;
+ }
+
+ led_set_brightness_nosleep(led_cdev, brightness);
+}
+EXPORT_SYMBOL_GPL(led_set_brightness);
+
+void led_set_brightness_nopm(struct led_classdev *led_cdev,
+ enum led_brightness value)
+{
+ /* Use brightness_set op if available, it is guaranteed not to sleep */
+ if (!__led_set_brightness(led_cdev, value))
+ return;
+
+ /* If brightness setting can sleep, delegate it to a work queue task */
+ led_cdev->delayed_set_value = value;
+ schedule_work(&led_cdev->set_brightness_work);
+}
+EXPORT_SYMBOL_GPL(led_set_brightness_nopm);
+
+void led_set_brightness_nosleep(struct led_classdev *led_cdev,
+ enum led_brightness value)
+{
+ led_cdev->brightness = min(value, led_cdev->max_brightness);
+
+ if (led_cdev->flags & LED_SUSPENDED)
+ return;
+
+ led_set_brightness_nopm(led_cdev, led_cdev->brightness);
+}
+EXPORT_SYMBOL_GPL(led_set_brightness_nosleep);
+
+int led_set_brightness_sync(struct led_classdev *led_cdev,
+ enum led_brightness value)
+{
+ if (led_cdev->blink_delay_on || led_cdev->blink_delay_off)
+ return -EBUSY;
+
+ led_cdev->brightness = min(value, led_cdev->max_brightness);
+
+ if (led_cdev->flags & LED_SUSPENDED)
+ return 0;
+
+ return __led_set_brightness_blocking(led_cdev, led_cdev->brightness);
+}
+EXPORT_SYMBOL_GPL(led_set_brightness_sync);
+
+int led_update_brightness(struct led_classdev *led_cdev)
+{
+ int ret = 0;
+
+ if (led_cdev->brightness_get) {
+ ret = led_cdev->brightness_get(led_cdev);
+ if (ret >= 0) {
+ led_cdev->brightness = ret;
+ return 0;
+ }
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(led_update_brightness);
+
+u32 *led_get_default_pattern(struct led_classdev *led_cdev, unsigned int *size)
+{
+ struct fwnode_handle *fwnode = led_cdev->dev->fwnode;
+ u32 *pattern;
+ int count;
+
+ count = fwnode_property_count_u32(fwnode, "led-pattern");
+ if (count < 0)
+ return NULL;
+
+ pattern = kcalloc(count, sizeof(*pattern), GFP_KERNEL);
+ if (!pattern)
+ return NULL;
+
+ if (fwnode_property_read_u32_array(fwnode, "led-pattern", pattern, count)) {
+ kfree(pattern);
+ return NULL;
+ }
+
+ *size = count;
+
+ return pattern;
+}
+EXPORT_SYMBOL_GPL(led_get_default_pattern);
+
+/* Caller must ensure led_cdev->led_access held */
+void led_sysfs_disable(struct led_classdev *led_cdev)
+{
+ lockdep_assert_held(&led_cdev->led_access);
+
+ led_cdev->flags |= LED_SYSFS_DISABLE;
+}
+EXPORT_SYMBOL_GPL(led_sysfs_disable);
+
+/* Caller must ensure led_cdev->led_access held */
+void led_sysfs_enable(struct led_classdev *led_cdev)
+{
+ lockdep_assert_held(&led_cdev->led_access);
+
+ led_cdev->flags &= ~LED_SYSFS_DISABLE;
+}
+EXPORT_SYMBOL_GPL(led_sysfs_enable);
+
+static void led_parse_fwnode_props(struct device *dev,
+ struct fwnode_handle *fwnode,
+ struct led_properties *props)
+{
+ int ret;
+
+ if (!fwnode)
+ return;
+
+ if (fwnode_property_present(fwnode, "label")) {
+ ret = fwnode_property_read_string(fwnode, "label", &props->label);
+ if (ret)
+ dev_err(dev, "Error parsing 'label' property (%d)\n", ret);
+ return;
+ }
+
+ if (fwnode_property_present(fwnode, "color")) {
+ ret = fwnode_property_read_u32(fwnode, "color", &props->color);
+ if (ret)
+ dev_err(dev, "Error parsing 'color' property (%d)\n", ret);
+ else if (props->color >= LED_COLOR_ID_MAX)
+ dev_err(dev, "LED color identifier out of range\n");
+ else
+ props->color_present = true;
+ }
+
+
+ if (!fwnode_property_present(fwnode, "function"))
+ return;
+
+ ret = fwnode_property_read_string(fwnode, "function", &props->function);
+ if (ret) {
+ dev_err(dev,
+ "Error parsing 'function' property (%d)\n",
+ ret);
+ }
+
+ if (!fwnode_property_present(fwnode, "function-enumerator"))
+ return;
+
+ ret = fwnode_property_read_u32(fwnode, "function-enumerator",
+ &props->func_enum);
+ if (ret) {
+ dev_err(dev,
+ "Error parsing 'function-enumerator' property (%d)\n",
+ ret);
+ } else {
+ props->func_enum_present = true;
+ }
+}
+
+int led_compose_name(struct device *dev, struct led_init_data *init_data,
+ char *led_classdev_name)
+{
+ struct led_properties props = {};
+ struct fwnode_handle *fwnode = init_data->fwnode;
+ const char *devicename = init_data->devicename;
+
+ /* We want to label LEDs that can produce full range of colors
+ * as RGB, not multicolor */
+ BUG_ON(props.color == LED_COLOR_ID_MULTI);
+
+ if (!led_classdev_name)
+ return -EINVAL;
+
+ led_parse_fwnode_props(dev, fwnode, &props);
+
+ if (props.label) {
+ /*
+ * If init_data.devicename is NULL, then it indicates that
+ * DT label should be used as-is for LED class device name.
+ * Otherwise the label is prepended with devicename to compose
+ * the final LED class device name.
+ */
+ if (!devicename) {
+ strscpy(led_classdev_name, props.label,
+ LED_MAX_NAME_SIZE);
+ } else {
+ snprintf(led_classdev_name, LED_MAX_NAME_SIZE, "%s:%s",
+ devicename, props.label);
+ }
+ } else if (props.function || props.color_present) {
+ char tmp_buf[LED_MAX_NAME_SIZE];
+
+ if (props.func_enum_present) {
+ snprintf(tmp_buf, LED_MAX_NAME_SIZE, "%s:%s-%d",
+ props.color_present ? led_colors[props.color] : "",
+ props.function ?: "", props.func_enum);
+ } else {
+ snprintf(tmp_buf, LED_MAX_NAME_SIZE, "%s:%s",
+ props.color_present ? led_colors[props.color] : "",
+ props.function ?: "");
+ }
+ if (init_data->devname_mandatory) {
+ snprintf(led_classdev_name, LED_MAX_NAME_SIZE, "%s:%s",
+ devicename, tmp_buf);
+ } else {
+ strscpy(led_classdev_name, tmp_buf, LED_MAX_NAME_SIZE);
+
+ }
+ } else if (init_data->default_label) {
+ if (!devicename) {
+ dev_err(dev, "Legacy LED naming requires devicename segment");
+ return -EINVAL;
+ }
+ snprintf(led_classdev_name, LED_MAX_NAME_SIZE, "%s:%s",
+ devicename, init_data->default_label);
+ } else if (is_of_node(fwnode)) {
+ strscpy(led_classdev_name, to_of_node(fwnode)->name,
+ LED_MAX_NAME_SIZE);
+ } else
+ return -EINVAL;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(led_compose_name);