diff options
Diffstat (limited to 'drivers/video/backlight/wm8350_bl.c')
| -rw-r--r-- | drivers/video/backlight/wm8350_bl.c | 299 |
1 files changed, 299 insertions, 0 deletions
diff --git a/drivers/video/backlight/wm8350_bl.c b/drivers/video/backlight/wm8350_bl.c new file mode 100644 index 000000000000..6865b753d8ce --- /dev/null +++ b/drivers/video/backlight/wm8350_bl.c @@ -0,0 +1,299 @@ +/* + * Backlight driver for DCDC2 on i.MX32ADS board + * + * Copyright(C) 2007 Wolfson Microelectronics PLC. + * Copyright (C) 2010 Freescale Semiconductor, Inc. + * + * 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/kernel.h> +#include <linux/init.h> +#include <linux/mutex.h> +#include <linux/fb.h> +#include <linux/platform_device.h> +#include <linux/backlight.h> +#include <linux/regulator/consumer.h> +#include <linux/mfd/wm8350/pmic.h> +#include <linux/mfd/wm8350/bl.h> + +struct wm8350_backlight { + struct backlight_properties props; + struct backlight_device *device; + struct regulator *dcdc; + struct regulator *isink; + struct notifier_block notifier; + struct work_struct work; + struct mutex mutex; + int intensity; + int suspend; + int retries; +}; + +/* hundredths of uA, 405 = 4.05 uA */ +static const int intensity_huA[] = { + 405, 482, 573, 681, 810, 963, 1146, 1362, 1620, 1927, 2291, 2725, + 3240, 3853, 4582, 5449, 6480, 7706, 9164, 10898, 12960, 15412, 18328, + 21796, 25920, 30824, 36656, 43592, 51840, 61648, 73313, 87184, + 103680, 123297, 146626, 174368, 207360, 246594, 293251, 348737, + 414720, 493188, 586503, 697473, 829440, 986376, 1173005, 1394946, + 1658880, 1972752, 2346011, 2789892, 3317760, 3945504, 4692021, + 5579785, 6635520, 7891008, 9384042, 11159570, 13271040, 15782015, + 18768085, 22319140, +}; + +static void bl_work(struct work_struct *work) +{ + struct wm8350_backlight *bl = + container_of(work, struct wm8350_backlight, work); + struct regulator *isink = bl->isink; + + mutex_lock(&bl->mutex); + if (bl->intensity >= 0 && + bl->intensity < ARRAY_SIZE(intensity_huA)) { + bl->retries = 0; + regulator_set_current_limit(isink, + 0, intensity_huA[bl->intensity] / 100); + } else + printk(KERN_ERR "wm8350: Backlight intensity error\n"); + mutex_unlock(&bl->mutex); +} + +static int wm8350_bl_notifier(struct notifier_block *self, + unsigned long event, void *data) +{ + struct wm8350_backlight *bl = + container_of(self, struct wm8350_backlight, notifier); + struct regulator *isink = bl->isink; + + if (event & REGULATOR_EVENT_UNDER_VOLTAGE) + printk(KERN_ERR "wm8350: BL DCDC undervoltage\n"); + if (event & REGULATOR_EVENT_REGULATION_OUT) + printk(KERN_ERR "wm8350: BL ISINK out of regulation\n"); + + mutex_lock(&bl->mutex); + if (bl->retries) { + bl->retries--; + regulator_disable(isink); + regulator_set_current_limit(isink, 0, bl->intensity); + regulator_enable(isink); + } else { + printk(KERN_ERR + "wm8350: BL regulation retry failure - disable\n"); + bl->intensity = 0; + regulator_disable(isink); + } + mutex_unlock(&bl->mutex); + return 0; +} + +static int wm8350_bl_send_intensity(struct backlight_device *bd) +{ + struct wm8350_backlight *bl = + (struct wm8350_backlight *)dev_get_drvdata(&bd->dev); + int intensity = bd->props.brightness; + + if (bd->props.power != FB_BLANK_UNBLANK) + intensity = 0; + if (bd->props.fb_blank != FB_BLANK_UNBLANK) + intensity = 0; + if (bl->suspend) + intensity = 0; + + mutex_lock(&bl->mutex); + bl->intensity = intensity; + mutex_unlock(&bl->mutex); + schedule_work(&bl->work); + + return 0; +} + +#ifdef CONFIG_PM +static int wm8350_bl_suspend(struct platform_device *pdev, pm_message_t state) +{ + struct wm8350_backlight *bl = + (struct wm8350_backlight *)platform_get_drvdata(pdev); + + bl->suspend = 1; + backlight_update_status(bl->device); + return 0; +} + +static int wm8350_bl_resume(struct platform_device *pdev) +{ + struct wm8350_backlight *bl = + (struct wm8350_backlight *)platform_get_drvdata(pdev); + + bl->suspend = 0; + backlight_update_status(bl->device); + return 0; +} +#else +#define wm8350_bl_suspend NULL +#define wm8350_bl_resume NULL +#endif + +static int wm8350_bl_get_intensity(struct backlight_device *bd) +{ + struct wm8350_backlight *bl = + (struct wm8350_backlight *)dev_get_drvdata(&bd->dev); + return bl->intensity; +} + +static struct backlight_ops wm8350_bl_ops = { + .get_brightness = wm8350_bl_get_intensity, + .update_status = wm8350_bl_send_intensity, +}; + +static int wm8350_bl_probe(struct platform_device *pdev) +{ + struct regulator *isink, *dcdc; + struct wm8350_backlight *bl; + struct wm8350_bl_platform_data *pdata = pdev->dev.platform_data; + struct wm8350 *pmic; + int ret; + + if (pdata == NULL) { + printk(KERN_ERR "%s: no platform data\n", __func__); + return -ENODEV; + } + + if (pdata->isink != WM8350_ISINK_A && pdata->isink != WM8350_ISINK_B) { + printk(KERN_ERR "%s: invalid ISINK\n", __func__); + return -EINVAL; + } + if (pdata->dcdc != WM8350_DCDC_2 && pdata->dcdc != WM8350_DCDC_5) { + printk(KERN_ERR "%s: invalid DCDC\n", __func__); + return -EINVAL; + } + + printk(KERN_INFO "wm8350: backlight using %s and %s\n", + pdata->isink == WM8350_ISINK_A ? "ISINKA" : "ISINKB", + pdata->dcdc == WM8350_DCDC_2 ? "DCDC2" : "DCDC5"); + + isink = regulator_get(&pdev->dev, + pdata->isink == WM8350_ISINK_A ? "ISINKA" : "ISINKB"); + if (IS_ERR(isink) || isink == NULL) { + printk(KERN_ERR "%s: cant get ISINK\n", __func__); + return PTR_ERR(isink); + } + + dcdc = regulator_get(&pdev->dev, + pdata->dcdc == WM8350_DCDC_2 ? "DCDC2" : "DCDC5"); + if (IS_ERR(dcdc) || dcdc == NULL) { + printk(KERN_ERR "%s: cant get DCDC\n", __func__); + regulator_put(isink); + return PTR_ERR(dcdc); + } + + bl = kzalloc(sizeof(*bl), GFP_KERNEL); + if (bl == NULL) { + regulator_put(isink); + regulator_put(dcdc); + return -ENOMEM; + } + + mutex_init(&bl->mutex); + INIT_WORK(&bl->work, bl_work); + bl->props.max_brightness = pdata->max_brightness; + bl->props.power = pdata->power; + bl->props.brightness = pdata->brightness; + bl->retries = pdata->retries; + bl->dcdc = dcdc; + bl->isink = isink; + platform_set_drvdata(pdev, bl); + pmic = regulator_get_drvdata(bl->isink); + + wm8350_bl_ops.check_fb = pdata->check_fb; + + bl->device = backlight_device_register(dev_name(&pdev->dev), &pdev->dev, + bl, &wm8350_bl_ops); + if (IS_ERR(bl->device)) { + ret = PTR_ERR(bl->device); + regulator_put(dcdc); + regulator_put(isink); + kfree(bl); + return ret; + } + + bl->notifier.notifier_call = wm8350_bl_notifier; + regulator_register_notifier(dcdc, &bl->notifier); + regulator_register_notifier(isink, &bl->notifier); + bl->device->props = bl->props; + + regulator_set_current_limit(isink, 0, 20000); + + wm8350_isink_set_flash(pmic, pdata->isink, + WM8350_ISINK_FLASH_DISABLE, + WM8350_ISINK_FLASH_TRIG_BIT, + WM8350_ISINK_FLASH_DUR_32MS, + WM8350_ISINK_FLASH_ON_1_00S, + WM8350_ISINK_FLASH_OFF_1_00S, + WM8350_ISINK_FLASH_MODE_EN); + + wm8350_dcdc25_set_mode(pmic, pdata->dcdc, + WM8350_ISINK_MODE_BOOST, WM8350_ISINK_ILIM_NORMAL, + pdata->voltage_ramp, pdata->isink == WM8350_ISINK_A ? + WM8350_DC5_FBSRC_ISINKA : WM8350_DC5_FBSRC_ISINKB); + + wm8350_dcdc_set_slot(pmic, pdata->dcdc, 15, 0, + pdata->dcdc == WM8350_DCDC_2 ? + WM8350_DC2_ERRACT_SHUTDOWN_CONV : WM8350_DC5_ERRACT_NONE); + + regulator_enable(isink); + backlight_update_status(bl->device); + return 0; +} + +static int wm8350_bl_remove(struct platform_device *pdev) +{ + struct wm8350_backlight *bl = + (struct wm8350_backlight *)platform_get_drvdata(pdev); + struct regulator *isink = bl->isink, *dcdc = bl->dcdc; + + bl->intensity = 0; + backlight_update_status(bl->device); + schedule_work(&bl->work); + flush_scheduled_work(); + backlight_device_unregister(bl->device); + + regulator_set_current_limit(isink, 0, 0); + regulator_disable(isink); + regulator_unregister_notifier(isink, &bl->notifier); + regulator_unregister_notifier(dcdc, &bl->notifier); + regulator_put(isink); + regulator_put(dcdc); + return 0; +} + +struct platform_driver imx32ads_backlight_driver = { + .driver = { + .name = "wm8350-bl", + .owner = THIS_MODULE, + }, + .probe = wm8350_bl_probe, + .remove = wm8350_bl_remove, + .suspend = wm8350_bl_suspend, + .resume = wm8350_bl_resume, +}; + +static int __devinit imx32ads_backlight_init(void) +{ + return platform_driver_register(&imx32ads_backlight_driver); +} + +static void imx32ads_backlight_exit(void) +{ + platform_driver_unregister(&imx32ads_backlight_driver); +} + +device_initcall_sync(imx32ads_backlight_init); +module_exit(imx32ads_backlight_exit); + +MODULE_AUTHOR("Liam Girdwood <lg@opensource.wolfsonmicro.com>"); +MODULE_DESCRIPTION("WM8350 Backlight driver"); +MODULE_LICENSE("GPL"); |