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authorKim, Milo <Milo.Kim@ti.com>2013-02-20 12:36:01 +0400
committerBryan Wu <cooloney@gmail.com>2013-04-01 22:04:48 +0400
commitf07fb52107c881f35eaff09fe990a4dfd0f7e62a (patch)
treeb4b338f39799781648b5c6e0782c9ad746733bca /drivers/leds/trigger/ledtrig-gpio.c
parentff45262a85dbf1bc74463c5dcea1d71a406d4d8e (diff)
downloadlinux-f07fb52107c881f35eaff09fe990a4dfd0f7e62a.tar.xz
leds: move LED trigger drivers into new subdirectory
For better driver management, new subdirectory, 'trigger' is created. All LED trigger drivers are moved into this directory. Internal header, 'leds.h' is included in each LED trigger drivers. Fix the location of header file, "leds.h" -> "../leds.h" in driver files. One exception is here, 'ledtrig-timer.c'. There is no need to include 'leds.h'. so '#include "leds.h"' line was removed. Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com> Signed-off-by: Bryan Wu <cooloney@gmail.com>
Diffstat (limited to 'drivers/leds/trigger/ledtrig-gpio.c')
-rw-r--r--drivers/leds/trigger/ledtrig-gpio.c253
1 files changed, 253 insertions, 0 deletions
diff --git a/drivers/leds/trigger/ledtrig-gpio.c b/drivers/leds/trigger/ledtrig-gpio.c
new file mode 100644
index 000000000000..35812e3a37f2
--- /dev/null
+++ b/drivers/leds/trigger/ledtrig-gpio.c
@@ -0,0 +1,253 @@
+/*
+ * ledtrig-gio.c - LED Trigger Based on GPIO events
+ *
+ * Copyright 2009 Felipe Balbi <me@felipebalbi.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/gpio.h>
+#include <linux/interrupt.h>
+#include <linux/workqueue.h>
+#include <linux/leds.h>
+#include <linux/slab.h>
+#include "../leds.h"
+
+struct gpio_trig_data {
+ struct led_classdev *led;
+ struct work_struct work;
+
+ unsigned desired_brightness; /* desired brightness when led is on */
+ unsigned inverted; /* true when gpio is inverted */
+ unsigned gpio; /* gpio that triggers the leds */
+};
+
+static irqreturn_t gpio_trig_irq(int irq, void *_led)
+{
+ struct led_classdev *led = _led;
+ struct gpio_trig_data *gpio_data = led->trigger_data;
+
+ /* just schedule_work since gpio_get_value can sleep */
+ schedule_work(&gpio_data->work);
+
+ return IRQ_HANDLED;
+};
+
+static void gpio_trig_work(struct work_struct *work)
+{
+ struct gpio_trig_data *gpio_data = container_of(work,
+ struct gpio_trig_data, work);
+ int tmp;
+
+ if (!gpio_data->gpio)
+ return;
+
+ tmp = gpio_get_value(gpio_data->gpio);
+ if (gpio_data->inverted)
+ tmp = !tmp;
+
+ if (tmp) {
+ if (gpio_data->desired_brightness)
+ __led_set_brightness(gpio_data->led,
+ gpio_data->desired_brightness);
+ else
+ __led_set_brightness(gpio_data->led, LED_FULL);
+ } else {
+ __led_set_brightness(gpio_data->led, LED_OFF);
+ }
+}
+
+static ssize_t gpio_trig_brightness_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct led_classdev *led = dev_get_drvdata(dev);
+ struct gpio_trig_data *gpio_data = led->trigger_data;
+
+ return sprintf(buf, "%u\n", gpio_data->desired_brightness);
+}
+
+static ssize_t gpio_trig_brightness_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t n)
+{
+ struct led_classdev *led = dev_get_drvdata(dev);
+ struct gpio_trig_data *gpio_data = led->trigger_data;
+ unsigned desired_brightness;
+ int ret;
+
+ ret = sscanf(buf, "%u", &desired_brightness);
+ if (ret < 1 || desired_brightness > 255) {
+ dev_err(dev, "invalid value\n");
+ return -EINVAL;
+ }
+
+ gpio_data->desired_brightness = desired_brightness;
+
+ return n;
+}
+static DEVICE_ATTR(desired_brightness, 0644, gpio_trig_brightness_show,
+ gpio_trig_brightness_store);
+
+static ssize_t gpio_trig_inverted_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct led_classdev *led = dev_get_drvdata(dev);
+ struct gpio_trig_data *gpio_data = led->trigger_data;
+
+ return sprintf(buf, "%u\n", gpio_data->inverted);
+}
+
+static ssize_t gpio_trig_inverted_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t n)
+{
+ struct led_classdev *led = dev_get_drvdata(dev);
+ struct gpio_trig_data *gpio_data = led->trigger_data;
+ unsigned long inverted;
+ int ret;
+
+ ret = kstrtoul(buf, 10, &inverted);
+ if (ret < 0)
+ return ret;
+
+ if (inverted > 1)
+ return -EINVAL;
+
+ gpio_data->inverted = inverted;
+
+ /* After inverting, we need to update the LED. */
+ schedule_work(&gpio_data->work);
+
+ return n;
+}
+static DEVICE_ATTR(inverted, 0644, gpio_trig_inverted_show,
+ gpio_trig_inverted_store);
+
+static ssize_t gpio_trig_gpio_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct led_classdev *led = dev_get_drvdata(dev);
+ struct gpio_trig_data *gpio_data = led->trigger_data;
+
+ return sprintf(buf, "%u\n", gpio_data->gpio);
+}
+
+static ssize_t gpio_trig_gpio_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t n)
+{
+ struct led_classdev *led = dev_get_drvdata(dev);
+ struct gpio_trig_data *gpio_data = led->trigger_data;
+ unsigned gpio;
+ int ret;
+
+ ret = sscanf(buf, "%u", &gpio);
+ if (ret < 1) {
+ dev_err(dev, "couldn't read gpio number\n");
+ flush_work(&gpio_data->work);
+ return -EINVAL;
+ }
+
+ if (gpio_data->gpio == gpio)
+ return n;
+
+ if (!gpio) {
+ if (gpio_data->gpio != 0)
+ free_irq(gpio_to_irq(gpio_data->gpio), led);
+ gpio_data->gpio = 0;
+ return n;
+ }
+
+ ret = request_irq(gpio_to_irq(gpio), gpio_trig_irq,
+ IRQF_SHARED | IRQF_TRIGGER_RISING
+ | IRQF_TRIGGER_FALLING, "ledtrig-gpio", led);
+ if (ret) {
+ dev_err(dev, "request_irq failed with error %d\n", ret);
+ } else {
+ if (gpio_data->gpio != 0)
+ free_irq(gpio_to_irq(gpio_data->gpio), led);
+ gpio_data->gpio = gpio;
+ }
+
+ return ret ? ret : n;
+}
+static DEVICE_ATTR(gpio, 0644, gpio_trig_gpio_show, gpio_trig_gpio_store);
+
+static void gpio_trig_activate(struct led_classdev *led)
+{
+ struct gpio_trig_data *gpio_data;
+ int ret;
+
+ gpio_data = kzalloc(sizeof(*gpio_data), GFP_KERNEL);
+ if (!gpio_data)
+ return;
+
+ ret = device_create_file(led->dev, &dev_attr_gpio);
+ if (ret)
+ goto err_gpio;
+
+ ret = device_create_file(led->dev, &dev_attr_inverted);
+ if (ret)
+ goto err_inverted;
+
+ ret = device_create_file(led->dev, &dev_attr_desired_brightness);
+ if (ret)
+ goto err_brightness;
+
+ gpio_data->led = led;
+ led->trigger_data = gpio_data;
+ INIT_WORK(&gpio_data->work, gpio_trig_work);
+ led->activated = true;
+
+ return;
+
+err_brightness:
+ device_remove_file(led->dev, &dev_attr_inverted);
+
+err_inverted:
+ device_remove_file(led->dev, &dev_attr_gpio);
+
+err_gpio:
+ kfree(gpio_data);
+}
+
+static void gpio_trig_deactivate(struct led_classdev *led)
+{
+ struct gpio_trig_data *gpio_data = led->trigger_data;
+
+ if (led->activated) {
+ device_remove_file(led->dev, &dev_attr_gpio);
+ device_remove_file(led->dev, &dev_attr_inverted);
+ device_remove_file(led->dev, &dev_attr_desired_brightness);
+ flush_work(&gpio_data->work);
+ if (gpio_data->gpio != 0)
+ free_irq(gpio_to_irq(gpio_data->gpio), led);
+ kfree(gpio_data);
+ led->activated = false;
+ }
+}
+
+static struct led_trigger gpio_led_trigger = {
+ .name = "gpio",
+ .activate = gpio_trig_activate,
+ .deactivate = gpio_trig_deactivate,
+};
+
+static int __init gpio_trig_init(void)
+{
+ return led_trigger_register(&gpio_led_trigger);
+}
+module_init(gpio_trig_init);
+
+static void __exit gpio_trig_exit(void)
+{
+ led_trigger_unregister(&gpio_led_trigger);
+}
+module_exit(gpio_trig_exit);
+
+MODULE_AUTHOR("Felipe Balbi <me@felipebalbi.com>");
+MODULE_DESCRIPTION("GPIO LED trigger");
+MODULE_LICENSE("GPL");