/* * TI LP8788 MFD - keyled driver * * Copyright 2012 Texas Instruments * * Author: Milo(Woogyom) Kim <milo.kim@ti.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/slab.h> #include <linux/err.h> #include <linux/platform_device.h> #include <linux/leds.h> #include <linux/mutex.h> #include <linux/mfd/lp8788.h> #include <linux/mfd/lp8788-isink.h> #define MAX_BRIGHTNESS LP8788_ISINK_MAX_PWM #define DEFAULT_LED_NAME "keyboard-backlight" struct lp8788_led { struct lp8788 *lp; struct mutex lock; struct work_struct work; struct led_classdev led_dev; enum lp8788_isink_number isink_num; enum led_brightness brightness; int on; }; struct lp8788_led_config { enum lp8788_isink_scale scale; enum lp8788_isink_number num; int iout; }; static struct lp8788_led_config default_led_config = { .scale = LP8788_ISINK_SCALE_100mA, .num = LP8788_ISINK_3, .iout = 0, }; static int lp8788_led_init_device(struct lp8788_led *led, struct lp8788_led_platform_data *pdata) { struct lp8788_led_config *cfg = &default_led_config; u8 addr, mask, val; int ret; if (pdata) { cfg->scale = pdata->scale; cfg->num = pdata->num; cfg->iout = pdata->iout_code; } led->isink_num = cfg->num; /* scale configuration */ addr = LP8788_ISINK_CTRL; mask = 1 << (cfg->num + LP8788_ISINK_SCALE_OFFSET); val = cfg->scale << (cfg->num + LP8788_ISINK_SCALE_OFFSET); ret = lp8788_update_bits(led->lp, addr, mask, val); if (ret) return ret; /* current configuration */ addr = lp8788_iout_addr[cfg->num]; mask = lp8788_iout_mask[cfg->num]; val = cfg->iout; return lp8788_update_bits(led->lp, addr, mask, val); } static void lp8788_led_enable(struct lp8788_led *led, enum lp8788_isink_number num, int on) { u8 mask = 1 << num; u8 val = on << num; if (lp8788_update_bits(led->lp, LP8788_ISINK_CTRL, mask, val)) return; led->on = on; } static void lp8788_led_work(struct work_struct *work) { struct lp8788_led *led = container_of(work, struct lp8788_led, work); enum lp8788_isink_number num = led->isink_num; int enable; u8 val = led->brightness; mutex_lock(&led->lock); switch (num) { case LP8788_ISINK_1: case LP8788_ISINK_2: case LP8788_ISINK_3: lp8788_write_byte(led->lp, lp8788_pwm_addr[num], val); break; default: mutex_unlock(&led->lock); return; } enable = (val > 0) ? 1 : 0; if (enable != led->on) lp8788_led_enable(led, num, enable); mutex_unlock(&led->lock); } static void lp8788_brightness_set(struct led_classdev *led_cdev, enum led_brightness brt_val) { struct lp8788_led *led = container_of(led_cdev, struct lp8788_led, led_dev); led->brightness = brt_val; schedule_work(&led->work); } static int lp8788_led_probe(struct platform_device *pdev) { struct lp8788 *lp = dev_get_drvdata(pdev->dev.parent); struct lp8788_led_platform_data *led_pdata; struct lp8788_led *led; struct device *dev = &pdev->dev; int ret; led = devm_kzalloc(dev, sizeof(struct lp8788_led), GFP_KERNEL); if (!led) return -ENOMEM; led->lp = lp; led->led_dev.max_brightness = MAX_BRIGHTNESS; led->led_dev.brightness_set = lp8788_brightness_set; led_pdata = lp->pdata ? lp->pdata->led_pdata : NULL; if (!led_pdata || !led_pdata->name) led->led_dev.name = DEFAULT_LED_NAME; else led->led_dev.name = led_pdata->name; mutex_init(&led->lock); INIT_WORK(&led->work, lp8788_led_work); platform_set_drvdata(pdev, led); ret = lp8788_led_init_device(led, led_pdata); if (ret) { dev_err(dev, "led init device err: %d\n", ret); return ret; } ret = led_classdev_register(dev, &led->led_dev); if (ret) { dev_err(dev, "led register err: %d\n", ret); return ret; } return 0; } static int lp8788_led_remove(struct platform_device *pdev) { struct lp8788_led *led = platform_get_drvdata(pdev); led_classdev_unregister(&led->led_dev); flush_work(&led->work); return 0; } static struct platform_driver lp8788_led_driver = { .probe = lp8788_led_probe, .remove = lp8788_led_remove, .driver = { .name = LP8788_DEV_KEYLED, }, }; module_platform_driver(lp8788_led_driver); MODULE_DESCRIPTION("Texas Instruments LP8788 Keyboard LED Driver"); MODULE_AUTHOR("Milo Kim"); MODULE_LICENSE("GPL"); MODULE_ALIAS("platform:lp8788-keyled");