[PATCH] LED: add LED device support for ixp4xx devices (6a0c51bf) · Commits · e / devices / android_kernel_teracube_2e

drivers/leds/Kconfig

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		@@ -43,6 +43,15 @@ config LEDS_SPITZ
		This option enables support for the LEDs on Sharp Zaurus
		SL-Cxx00 series (C1000, C3000, C3100).

		config LEDS_IXP4XX
		tristate "LED Support for GPIO connected LEDs on IXP4XX processors"
		depends LEDS_CLASS && ARCH_IXP4XX
		help
		This option enables support for the LEDs connected to GPIO
		outputs of the Intel IXP4XX processors. To be useful the
		particular board must have LEDs and they must be connected
		to the GPIO lines. If unsure, say Y.

		config LEDS_TRIGGER_TIMER
		tristate "LED Timer Trigger"
		depends LEDS_TRIGGERS

drivers/leds/Makefile

+1 −0

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		@@ -8,6 +8,7 @@ obj-$(CONFIG_LEDS_TRIGGERS) += led-triggers.o
		obj-$(CONFIG_LEDS_CORGI) += leds-corgi.o
		obj-$(CONFIG_LEDS_LOCOMO) += leds-locomo.o
		obj-$(CONFIG_LEDS_SPITZ) += leds-spitz.o
		obj-$(CONFIG_LEDS_IXP4XX) += leds-ixp4xx-gpio.o

		# LED Triggers
		obj-$(CONFIG_LEDS_TRIGGER_TIMER) += ledtrig-timer.o

drivers/leds/leds-ixp4xx-gpio.c

0 → 100644

+215 −0

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		/*
		* IXP4XX GPIO driver LED driver
		*
		* Author: John Bowler <jbowler@acm.org>
		*
		* Copyright (c) 2006 John Bowler
		*
		* Permission is hereby granted, free of charge, to any
		* person obtaining a copy of this software and associated
		* documentation files (the "Software"), to deal in the
		* Software without restriction, including without
		* limitation the rights to use, copy, modify, merge,
		* publish, distribute, sublicense, and/or sell copies of
		* the Software, and to permit persons to whom the
		* Software is furnished to do so, subject to the
		* following conditions:
		*
		* The above copyright notice and this permission notice
		* shall be included in all copies or substantial portions
		* of the Software.
		*
		* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
		* ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
		* TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
		* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
		* SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
		* ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
		* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
		* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
		* OTHER DEALINGS IN THE SOFTWARE.
		*
		*/

		#include <linux/config.h>
		#include <linux/kernel.h>
		#include <linux/init.h>
		#include <linux/platform_device.h>
		#include <linux/spinlock.h>
		#include <linux/leds.h>
		#include <asm/arch/hardware.h>

		extern spinlock_t gpio_lock;

		/* Up to 16 gpio lines are possible. */
		#define GPIO_MAX 16
		static struct ixp4xxgpioled_device {
		struct led_classdev ancestor;
		int flags;
		} ixp4xxgpioled_devices[GPIO_MAX];

		void ixp4xxgpioled_brightness_set(struct led_classdev *pled,
		enum led_brightness value)
		{
		const struct ixp4xxgpioled_device *const ixp4xx_dev =
		container_of(pled, struct ixp4xxgpioled_device, ancestor);
		const u32 gpio_pin = ixp4xx_dev - ixp4xxgpioled_devices;

		if (gpio_pin < GPIO_MAX && ixp4xx_dev->ancestor.name != 0) {
		/* Set or clear the 'gpio_pin' bit according to the style
		* and the required setting (value > 0 == on)
		*/
		const int gpio_value =
		(value > 0) == (ixp4xx_dev->flags != IXP4XX_GPIO_LOW) ?
		IXP4XX_GPIO_HIGH : IXP4XX_GPIO_LOW;

		{
		unsigned long flags;
		spin_lock_irqsave(&gpio_lock, flags);
		gpio_line_set(gpio_pin, gpio_value);
		spin_unlock_irqrestore(&gpio_lock, flags);
		}
		}
		}

		/* LEDs are described in resources, the following iterates over the valid
		* LED resources.
		*/
		#define for_all_leds(i, pdev) \
		for (i=0; i<pdev->num_resources; ++i) \
		if (pdev->resource[i].start < GPIO_MAX && \
		pdev->resource[i].name != 0)

		/* The following applies 'operation' to each LED from the given platform,
		* the function always returns 0 to allow tail call elimination.
		*/
		static int apply_to_all_leds(struct platform_device *pdev,
		void (operation)(struct led_classdev pled))
		{
		int i;

		for_all_leds(i, pdev)
		operation(&ixp4xxgpioled_devices[pdev->resource[i].start].ancestor);
		return 0;
		}

		#ifdef CONFIG_PM
		static int ixp4xxgpioled_suspend(struct platform_device *pdev,
		pm_message_t state)
		{
		return apply_to_all_leds(pdev, led_classdev_suspend);
		}

		static int ixp4xxgpioled_resume(struct platform_device *pdev)
		{
		return apply_to_all_leds(pdev, led_classdev_resume);
		}
		#endif

		static void ixp4xxgpioled_remove_one_led(struct led_classdev *pled)
		{
		led_classdev_unregister(pled);
		pled->name = 0;
		}

		static int ixp4xxgpioled_remove(struct platform_device *pdev)
		{
		return apply_to_all_leds(pdev, ixp4xxgpioled_remove_one_led);
		}

		static int ixp4xxgpioled_probe(struct platform_device *pdev)
		{
		/* The board level has to tell the driver where the
		* LEDs are connected - there is no way to find out
		* electrically. It must also say whether the GPIO
		* lines are active high or active low.
		*
		* To do this read the num_resources (the number of
		* LEDs) and the struct resource (the data for each
		* LED). The name comes from the resource, and it
		* isn't copied.
		*/
		int i;

		for_all_leds(i, pdev) {
		const u8 gpio_pin = pdev->resource[i].start;
		int rc;

		if (ixp4xxgpioled_devices[gpio_pin].ancestor.name == 0) {
		unsigned long flags;

		spin_lock_irqsave(&gpio_lock, flags);
		gpio_line_config(gpio_pin, IXP4XX_GPIO_OUT);
		/* The config can, apparently, reset the state,
		* I suspect the gpio line may be an input and
		* the config may cause the line to be latched,
		* so the setting depends on how the LED is
		* connected to the line (which affects how it
		* floats if not driven).
		*/
		gpio_line_set(gpio_pin, IXP4XX_GPIO_HIGH);
		spin_unlock_irqrestore(&gpio_lock, flags);

		ixp4xxgpioled_devices[gpio_pin].flags =
		pdev->resource[i].flags & IORESOURCE_BITS;

		ixp4xxgpioled_devices[gpio_pin].ancestor.name =
		pdev->resource[i].name;

		/* This is how a board manufacturer makes the LED
		* come on on reset - the GPIO line will be high, so
		* make the LED light when the line is low...
		*/
		if (ixp4xxgpioled_devices[gpio_pin].flags != IXP4XX_GPIO_LOW)
		ixp4xxgpioled_devices[gpio_pin].ancestor.brightness = 100;
		else
		ixp4xxgpioled_devices[gpio_pin].ancestor.brightness = 0;

		ixp4xxgpioled_devices[gpio_pin].ancestor.flags = 0;

		ixp4xxgpioled_devices[gpio_pin].ancestor.brightness_set =
		ixp4xxgpioled_brightness_set;

		ixp4xxgpioled_devices[gpio_pin].ancestor.default_trigger = 0;
		}

		rc = led_classdev_register(&pdev->dev,
		&ixp4xxgpioled_devices[gpio_pin].ancestor);
		if (rc < 0) {
		ixp4xxgpioled_devices[gpio_pin].ancestor.name = 0;
		ixp4xxgpioled_remove(pdev);
		return rc;
		}
		}

		return 0;
		}

		static struct platform_driver ixp4xxgpioled_driver = {
		.probe = ixp4xxgpioled_probe,
		.remove = ixp4xxgpioled_remove,
		#ifdef CONFIG_PM
		.suspend = ixp4xxgpioled_suspend,
		.resume = ixp4xxgpioled_resume,
		#endif
		.driver = {
		.name = "IXP4XX-GPIO-LED",
		},
		};

		static int __init ixp4xxgpioled_init(void)
		{
		return platform_driver_register(&ixp4xxgpioled_driver);
		}

		static void __exit ixp4xxgpioled_exit(void)
		{
		platform_driver_unregister(&ixp4xxgpioled_driver);
		}

		module_init(ixp4xxgpioled_init);
		module_exit(ixp4xxgpioled_exit);

		MODULE_AUTHOR("John Bowler <jbowler@acm.org>");
		MODULE_DESCRIPTION("IXP4XX GPIO LED driver");
		MODULE_LICENSE("Dual MIT/GPL");