diff options
Diffstat (limited to 'drivers/leds/leds-lp8788.c')
| -rw-r--r-- | drivers/leds/leds-lp8788.c | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/drivers/leds/leds-lp8788.c b/drivers/leds/leds-lp8788.c new file mode 100644 index 000000000000..574b49f79093 --- /dev/null +++ b/drivers/leds/leds-lp8788.c @@ -0,0 +1,192 @@ +/* + * 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; + 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: + 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 __devinit 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; + int ret; + + led = devm_kzalloc(lp->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(lp->dev, "led init device err: %d\n", ret); + return ret; + } + + ret = led_classdev_register(lp->dev, &led->led_dev); + if (ret) { + dev_err(lp->dev, "led register err: %d\n", ret); + return ret; + } + + return 0; +} + +static int __devexit lp8788_led_remove(struct platform_device *pdev) +{ + struct lp8788_led *led = platform_get_drvdata(pdev); + + led_classdev_unregister(&led->led_dev); + flush_work_sync(&led->work); + + return 0; +} + +static struct platform_driver lp8788_led_driver = { + .probe = lp8788_led_probe, + .remove = __devexit_p(lp8788_led_remove), + .driver = { + .name = LP8788_DEV_KEYLED, + .owner = THIS_MODULE, + }, +}; +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"); |