1 --- a/drivers/leds/Kconfig
2 +++ b/drivers/leds/Kconfig
3 @@ -251,6 +251,12 @@ config LEDS_LP8788
5 This option enables support for the Keyboard LEDs on the LP8788 PMIC.
8 + tristate "LED Support for Memory Latched LEDs"
9 + depends on LEDS_CLASS
13 config LEDS_CLEVO_MAIL
14 tristate "Mail LED on Clevo notebook"
16 --- a/drivers/leds/Makefile
17 +++ b/drivers/leds/Makefile
18 @@ -22,6 +22,7 @@ obj-$(CONFIG_LEDS_SUNFIRE) += leds-sunf
19 obj-$(CONFIG_LEDS_PCA9532) += leds-pca9532.o
20 obj-$(CONFIG_LEDS_GPIO_REGISTER) += leds-gpio-register.o
21 obj-$(CONFIG_LEDS_GPIO) += leds-gpio.o
22 +obj-$(CONFIG_LEDS_LATCH) += leds-latch.o
23 obj-$(CONFIG_LEDS_LP3944) += leds-lp3944.o
24 obj-$(CONFIG_LEDS_LP55XX_COMMON) += leds-lp55xx-common.o
25 obj-$(CONFIG_LEDS_LP5521) += leds-lp5521.o
27 +++ b/drivers/leds/leds-latch.c
30 + * LEDs driver for Memory Latched Devices
32 + * Copyright (C) 2008 Gateworks Corp.
33 + * Chris Lang <clang@gateworks.com>
35 + * This program is free software; you can redistribute it and/or modify
36 + * it under the terms of the GNU General Public License version 2 as
37 + * published by the Free Software Foundation.
40 +#include <linux/kernel.h>
41 +#include <linux/slab.h>
42 +#include <linux/init.h>
43 +#include <linux/platform_device.h>
44 +#include <linux/leds.h>
45 +#include <linux/workqueue.h>
47 +#include <linux/spinlock.h>
48 +#include <linux/slab.h>
49 +#include <linux/module.h>
50 +#include <linux/export.h>
52 +static unsigned int mem_keep = 0xFF;
53 +static spinlock_t mem_lock;
54 +static unsigned char *iobase;
56 +struct latch_led_data {
57 + struct led_classdev cdev;
58 + struct work_struct work;
61 + void (*set_led)(u8 bit, enum led_brightness value);
64 +static void latch_set_led(u8 bit, enum led_brightness value)
66 + if (value == LED_OFF)
67 + mem_keep |= (0x1 << bit);
69 + mem_keep &= ~(0x1 << bit);
71 + writeb(mem_keep, iobase);
74 +static void latch_led_set(struct led_classdev *led_cdev,
75 + enum led_brightness value)
77 + struct latch_led_data *led_dat =
78 + container_of(led_cdev, struct latch_led_data, cdev);
80 + raw_spin_lock(mem_lock);
82 + led_dat->set_led(led_dat->bit, value);
84 + raw_spin_unlock(mem_lock);
87 +static int latch_led_probe(struct platform_device *pdev)
89 + struct latch_led_platform_data *pdata = pdev->dev.platform_data;
90 + struct latch_led *cur_led;
91 + struct latch_led_data *leds_data, *led_dat;
97 + leds_data = kzalloc(sizeof(struct latch_led_data) * pdata->num_leds,
102 + for (i = 0; i < pdata->num_leds; i++) {
103 + cur_led = &pdata->leds[i];
104 + led_dat = &leds_data[i];
106 + led_dat->cdev.name = cur_led->name;
107 + led_dat->cdev.default_trigger = cur_led->default_trigger;
108 + led_dat->cdev.brightness_set = latch_led_set;
109 + led_dat->cdev.brightness = LED_OFF;
110 + led_dat->bit = cur_led->bit;
111 + led_dat->set_led = pdata->set_led ? pdata->set_led : latch_set_led;
113 + ret = led_classdev_register(&pdev->dev, &led_dat->cdev);
119 + if (!pdata->set_led) {
120 + iobase = ioremap_nocache(pdata->mem, 0x1000);
121 + writeb(0xFF, iobase);
123 + platform_set_drvdata(pdev, leds_data);
129 + for (i = i - 1; i >= 0; i--) {
130 + led_classdev_unregister(&leds_data[i].cdev);
139 +static int latch_led_remove(struct platform_device *pdev)
142 + struct latch_led_platform_data *pdata = pdev->dev.platform_data;
143 + struct latch_led_data *leds_data;
145 + leds_data = platform_get_drvdata(pdev);
147 + for (i = 0; i < pdata->num_leds; i++) {
148 + led_classdev_unregister(&leds_data[i].cdev);
149 + cancel_work_sync(&leds_data[i].work);
157 +static struct platform_driver latch_led_driver = {
158 + .probe = latch_led_probe,
159 + .remove = latch_led_remove,
161 + .name = "leds-latch",
162 + .owner = THIS_MODULE,
166 +static int __init latch_led_init(void)
168 + return platform_driver_register(&latch_led_driver);
171 +static void __exit latch_led_exit(void)
173 + platform_driver_unregister(&latch_led_driver);
176 +module_init(latch_led_init);
177 +module_exit(latch_led_exit);
179 +MODULE_AUTHOR("Chris Lang <clang@gateworks.com>");
180 +MODULE_DESCRIPTION("Latch LED driver");
181 --- a/include/linux/leds.h
182 +++ b/include/linux/leds.h
183 @@ -285,4 +285,18 @@ static inline void ledtrig_cpu(enum cpu_
187 +/* For the leds-latch driver */
190 + char *default_trigger;
194 +struct latch_led_platform_data {
197 + struct latch_led *leds;
198 + void (*set_led)(u8 bit, enum led_brightness value);
201 #endif /* __LINUX_LEDS_H_INCLUDED */