--- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -239,6 +239,12 @@ config LEDS_LP8788 help This option enables support for the Keyboard LEDs on the LP8788 PMIC. +config LEDS_LATCH + tristate "LED Support for Memory Latched LEDs" + depends on LEDS_CLASS + help + -- To Do -- + config LEDS_CLEVO_MAIL tristate "Mail LED on Clevo notebook" depends on LEDS_CLASS --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -22,6 +22,7 @@ obj-$(CONFIG_LEDS_SUNFIRE) += leds-sunf obj-$(CONFIG_LEDS_PCA9532) += leds-pca9532.o obj-$(CONFIG_LEDS_GPIO_REGISTER) += leds-gpio-register.o obj-$(CONFIG_LEDS_GPIO) += leds-gpio.o +obj-$(CONFIG_LEDS_LATCH) += leds-latch.o obj-$(CONFIG_LEDS_LP3944) += leds-lp3944.o obj-$(CONFIG_LEDS_LP55XX_COMMON) += leds-lp55xx-common.o obj-$(CONFIG_LEDS_LP5521) += leds-lp5521.o --- /dev/null +++ b/drivers/leds/leds-latch.c @@ -0,0 +1,152 @@ +/* + * LEDs driver for Memory Latched Devices + * + * Copyright (C) 2008 Gateworks Corp. + * Chris Lang <clang@gateworks.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/slab.h> +#include <linux/init.h> +#include <linux/platform_device.h> +#include <linux/leds.h> +#include <linux/workqueue.h> +#include <asm/io.h> +#include <linux/spinlock.h> +#include <linux/slab.h> +#include <linux/module.h> +#include <linux/export.h> + +static unsigned int mem_keep = 0xFF; +static spinlock_t mem_lock; +static unsigned char *iobase; + +struct latch_led_data { + struct led_classdev cdev; + struct work_struct work; + u8 new_level; + u8 bit; + void (*set_led)(u8 bit, enum led_brightness value); +}; + +static void latch_set_led(u8 bit, enum led_brightness value) +{ + if (value == LED_OFF) + mem_keep |= (0x1 << bit); + else + mem_keep &= ~(0x1 << bit); + + writeb(mem_keep, iobase); +} + +static void latch_led_set(struct led_classdev *led_cdev, + enum led_brightness value) +{ + struct latch_led_data *led_dat = + container_of(led_cdev, struct latch_led_data, cdev); + + raw_spin_lock(mem_lock); + + led_dat->set_led(led_dat->bit, value); + + raw_spin_unlock(mem_lock); +} + +static int latch_led_probe(struct platform_device *pdev) +{ + struct latch_led_platform_data *pdata = pdev->dev.platform_data; + struct latch_led *cur_led; + struct latch_led_data *leds_data, *led_dat; + int i, ret = 0; + + if (!pdata) + return -EBUSY; + + leds_data = kzalloc(sizeof(struct latch_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->cdev.brightness_set = latch_led_set; + led_dat->cdev.brightness = LED_OFF; + led_dat->bit = cur_led->bit; + led_dat->set_led = pdata->set_led ? pdata->set_led : latch_set_led; + + ret = led_classdev_register(&pdev->dev, &led_dat->cdev); + if (ret < 0) { + goto err; + } + } + + if (!pdata->set_led) { + iobase = ioremap_nocache(pdata->mem, 0x1000); + writeb(0xFF, iobase); + } + 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); + } + } + + kfree(leds_data); + + return ret; +} + +static int latch_led_remove(struct platform_device *pdev) +{ + int i; + struct latch_led_platform_data *pdata = pdev->dev.platform_data; + struct latch_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); + cancel_work_sync(&leds_data[i].work); + } + + kfree(leds_data); + + return 0; +} + +static struct platform_driver latch_led_driver = { + .probe = latch_led_probe, + .remove = latch_led_remove, + .driver = { + .name = "leds-latch", + .owner = THIS_MODULE, + }, +}; + +static int __init latch_led_init(void) +{ + return platform_driver_register(&latch_led_driver); +} + +static void __exit latch_led_exit(void) +{ + platform_driver_unregister(&latch_led_driver); +} + +module_init(latch_led_init); +module_exit(latch_led_exit); + +MODULE_AUTHOR("Chris Lang <clang@gateworks.com>"); +MODULE_DESCRIPTION("Latch LED driver"); --- a/include/linux/leds.h +++ b/include/linux/leds.h @@ -285,4 +285,18 @@ static inline void ledtrig_cpu(enum cpu_ } #endif +/* For the leds-latch driver */ +struct latch_led { + const char *name; + char *default_trigger; + unsigned bit; +}; + +struct latch_led_platform_data { + int num_leds; + u32 mem; + struct latch_led *leds; + void (*set_led)(u8 bit, enum led_brightness value); +}; + #endif /* __LINUX_LEDS_H_INCLUDED */