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authorRaphael Assenat <raph@8d.com>2007-02-27 19:49:53 +0000
committerRichard Purdie <rpurdie@rpsys.net>2007-07-16 01:15:50 +0100
commit22e03f3b58dfcca30f0c8de185022132459638d1 (patch)
tree0597fa494d55f44191ec99b4bb34a937efcab0e7 /drivers/leds
parent8f41958bdd577731f7411c9605cfaa9db6766809 (diff)
downloadop-kernel-dev-22e03f3b58dfcca30f0c8de185022132459638d1.zip
op-kernel-dev-22e03f3b58dfcca30f0c8de185022132459638d1.tar.gz
leds: Add generic GPIO LED driver
This patch adds support for GPIO connected leds via the new GPIO framework. Information about leds (gpio, polarity, name, default trigger) is passed to the driver via platform_data. Signed-off-by: Raphael Assenat <raph@8d.com> Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Diffstat (limited to 'drivers/leds')
-rw-r--r--drivers/leds/Kconfig8
-rw-r--r--drivers/leds/Makefile1
-rw-r--r--drivers/leds/leds-gpio.c174
3 files changed, 183 insertions, 0 deletions
diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index 87d2046..9ce3ca1 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -95,6 +95,14 @@ config LEDS_COBALT
help
This option enables support for the front LED on Cobalt Server
+config LEDS_GPIO
+ tristate "LED Support for GPIO connected LEDs"
+ depends on LEDS_CLASS && GENERIC_GPIO
+ help
+ This option enables support for the LEDs connected to GPIO
+ outputs. To be useful the particular board must have LEDs
+ and they must be connected to the GPIO lines.
+
comment "LED Triggers"
config LEDS_TRIGGERS
diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile
index aa2c18e..f8995c9 100644
--- a/drivers/leds/Makefile
+++ b/drivers/leds/Makefile
@@ -16,6 +16,7 @@ obj-$(CONFIG_LEDS_NET48XX) += leds-net48xx.o
obj-$(CONFIG_LEDS_WRAP) += leds-wrap.o
obj-$(CONFIG_LEDS_H1940) += leds-h1940.o
obj-$(CONFIG_LEDS_COBALT) += leds-cobalt.o
+obj-$(CONFIG_LEDS_GPIO) += leds-gpio.o
# LED Triggers
obj-$(CONFIG_LEDS_TRIGGER_TIMER) += ledtrig-timer.o
diff --git a/drivers/leds/leds-gpio.c b/drivers/leds/leds-gpio.c
new file mode 100644
index 0000000..431dcb6
--- /dev/null
+++ b/drivers/leds/leds-gpio.c
@@ -0,0 +1,174 @@
+/*
+ * LEDs driver for GPIOs
+ *
+ * Copyright (C) 2007 8D Technologies inc.
+ * Raphael Assenat <raph@8d.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/kernel.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/leds.h>
+#include <asm/gpio.h>
+
+struct gpio_led_data {
+ struct led_classdev cdev;
+ unsigned gpio;
+ u8 active_low;
+};
+
+
+static void gpio_led_set(struct led_classdev *led_cdev,
+ enum led_brightness value)
+{
+ struct gpio_led_data *led_dat =
+ container_of(led_cdev, struct gpio_led_data, cdev);
+ int level;
+
+ if (value == LED_OFF)
+ level = 0;
+ else
+ level = 1;
+
+ if (led_dat->active_low)
+ level = !level;
+
+ gpio_set_value(led_dat->gpio, level);
+}
+
+static int __init gpio_led_probe(struct platform_device *pdev)
+{
+ struct gpio_led_platform_data *pdata = pdev->dev.platform_data;
+ struct gpio_led *cur_led;
+ struct gpio_led_data *leds_data, *led_dat;
+ int i, ret = 0;
+
+ if (!pdata)
+ return -EBUSY;
+
+ leds_data = kzalloc(sizeof(struct gpio_led_data) * pdata->num_leds,
+ GFP_KERNEL);
+ if (!leds_data)
+ return -ENOMEM;
+
+ for (i = 0; i < pdata->num_leds; i++) {
+ cur_led = &pdata->leds[i];
+ led_dat = &leds_data[i];
+
+ led_dat->cdev.name = cur_led->name;
+ led_dat->cdev.default_trigger = cur_led->default_trigger;
+ led_dat->gpio = cur_led->gpio;
+ led_dat->active_low = cur_led->active_low;
+ led_dat->cdev.brightness_set = gpio_led_set;
+ led_dat->cdev.brightness = cur_led->active_low ? LED_FULL : LED_OFF;
+
+ ret = gpio_request(led_dat->gpio, led_dat->cdev.name);
+ if (ret < 0)
+ goto err;
+
+ gpio_direction_output(led_dat->gpio, led_dat->active_low);
+
+ ret = led_classdev_register(&pdev->dev, &led_dat->cdev);
+ if (ret < 0) {
+ gpio_free(led_dat->gpio);
+ goto err;
+ }
+ }
+
+ platform_set_drvdata(pdev, leds_data);
+
+ return 0;
+
+err:
+ if (i > 0) {
+ for (i = i - 1; i >= 0; i--) {
+ led_classdev_unregister(&leds_data[i].cdev);
+ gpio_free(leds_data[i].gpio);
+ }
+ }
+ kfree(leds_data);
+
+ return ret;
+}
+
+static int __exit gpio_led_remove(struct platform_device *pdev)
+{
+ int i;
+ struct gpio_led_platform_data *pdata = pdev->dev.platform_data;
+ struct gpio_led_data *leds_data;
+
+ leds_data = platform_get_drvdata(pdev);
+
+ for (i = 0; i < pdata->num_leds; i++) {
+ led_classdev_unregister(&leds_data[i].cdev);
+ gpio_free(leds_data[i].gpio);
+ }
+
+ kfree(leds_data);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int gpio_led_suspend(struct platform_device *pdev, pm_message_t state)
+{
+ struct gpio_led_platform_data *pdata = pdev->dev.platform_data;
+ struct gpio_led_data *leds_data;
+ int i;
+
+ leds_data = platform_get_drvdata(pdev);
+
+ for (i = 0; i < pdata->num_leds; i++)
+ led_classdev_suspend(&leds_data[i].cdev);
+
+ return 0;
+}
+
+static int gpio_led_resume(struct platform_device *pdev)
+{
+ struct gpio_led_platform_data *pdata = pdev->dev.platform_data;
+ struct gpio_led_data *leds_data;
+ int i;
+
+ leds_data = platform_get_drvdata(pdev);
+
+ for (i = 0; i < pdata->num_leds; i++)
+ led_classdev_resume(&leds_data[i].cdev);
+
+ return 0;
+}
+#else
+#define gpio_led_suspend NULL
+#define gpio_led_resume NULL
+#endif
+
+static struct platform_driver gpio_led_driver = {
+ .remove = __exit_p(gpio_led_remove),
+ .suspend = gpio_led_suspend,
+ .resume = gpio_led_resume,
+ .driver = {
+ .name = "leds-gpio",
+ .owner = THIS_MODULE,
+ },
+};
+
+static int __init gpio_led_init(void)
+{
+ return platform_driver_probe(&gpio_led_driver, gpio_led_probe);
+}
+
+static void __exit gpio_led_exit(void)
+{
+ platform_driver_unregister(&gpio_led_driver);
+}
+
+module_init(gpio_led_init);
+module_exit(gpio_led_exit);
+
+MODULE_AUTHOR("Raphael Assenat <raph@8d.com>");
+MODULE_DESCRIPTION("GPIO LED driver");
+MODULE_LICENSE("GPL");
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