diff options
Diffstat (limited to 'drivers/video/backlight/da903x_bl.c')
| -rw-r--r-- | drivers/video/backlight/da903x_bl.c | 175 |
1 files changed, 175 insertions, 0 deletions
diff --git a/drivers/video/backlight/da903x_bl.c b/drivers/video/backlight/da903x_bl.c new file mode 100644 index 000000000..f793738f0 --- /dev/null +++ b/drivers/video/backlight/da903x_bl.c @@ -0,0 +1,175 @@ +/* + * Backlight driver for Dialog Semiconductor DA9030/DA9034 + * + * Copyright (C) 2008 Compulab, Ltd. + * Mike Rapoport <mike@compulab.co.il> + * + * Copyright (C) 2006-2008 Marvell International Ltd. + * Eric Miao <eric.miao@marvell.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/init.h> +#include <linux/platform_device.h> +#include <linux/fb.h> +#include <linux/backlight.h> +#include <linux/mfd/da903x.h> +#include <linux/slab.h> +#include <linux/module.h> + +#define DA9030_WLED_CONTROL 0x25 +#define DA9030_WLED_CP_EN (1 << 6) +#define DA9030_WLED_TRIM(x) ((x) & 0x7) + +#define DA9034_WLED_CONTROL1 0x3C +#define DA9034_WLED_CONTROL2 0x3D +#define DA9034_WLED_ISET(x) ((x) & 0x1f) + +#define DA9034_WLED_BOOST_EN (1 << 5) + +#define DA9030_MAX_BRIGHTNESS 7 +#define DA9034_MAX_BRIGHTNESS 0x7f + +struct da903x_backlight_data { + struct device *da903x_dev; + int id; + int current_brightness; +}; + +static int da903x_backlight_set(struct backlight_device *bl, int brightness) +{ + struct da903x_backlight_data *data = bl_get_data(bl); + struct device *dev = data->da903x_dev; + uint8_t val; + int ret = 0; + + switch (data->id) { + case DA9034_ID_WLED: + ret = da903x_update(dev, DA9034_WLED_CONTROL1, + brightness, 0x7f); + if (ret) + return ret; + + if (data->current_brightness && brightness == 0) + ret = da903x_clr_bits(dev, + DA9034_WLED_CONTROL2, + DA9034_WLED_BOOST_EN); + + if (data->current_brightness == 0 && brightness) + ret = da903x_set_bits(dev, + DA9034_WLED_CONTROL2, + DA9034_WLED_BOOST_EN); + break; + case DA9030_ID_WLED: + val = DA9030_WLED_TRIM(brightness); + val |= brightness ? DA9030_WLED_CP_EN : 0; + ret = da903x_write(dev, DA9030_WLED_CONTROL, val); + break; + } + + if (ret) + return ret; + + data->current_brightness = brightness; + return 0; +} + +static int da903x_backlight_update_status(struct backlight_device *bl) +{ + int brightness = bl->props.brightness; + + if (bl->props.power != FB_BLANK_UNBLANK) + brightness = 0; + + if (bl->props.fb_blank != FB_BLANK_UNBLANK) + brightness = 0; + + if (bl->props.state & BL_CORE_SUSPENDED) + brightness = 0; + + return da903x_backlight_set(bl, brightness); +} + +static int da903x_backlight_get_brightness(struct backlight_device *bl) +{ + struct da903x_backlight_data *data = bl_get_data(bl); + + return data->current_brightness; +} + +static const struct backlight_ops da903x_backlight_ops = { + .options = BL_CORE_SUSPENDRESUME, + .update_status = da903x_backlight_update_status, + .get_brightness = da903x_backlight_get_brightness, +}; + +static int da903x_backlight_probe(struct platform_device *pdev) +{ + struct da9034_backlight_pdata *pdata = dev_get_platdata(&pdev->dev); + struct da903x_backlight_data *data; + struct backlight_device *bl; + struct backlight_properties props; + int max_brightness; + + data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); + if (data == NULL) + return -ENOMEM; + + switch (pdev->id) { + case DA9030_ID_WLED: + max_brightness = DA9030_MAX_BRIGHTNESS; + break; + case DA9034_ID_WLED: + max_brightness = DA9034_MAX_BRIGHTNESS; + break; + default: + dev_err(&pdev->dev, "invalid backlight device ID(%d)\n", + pdev->id); + return -EINVAL; + } + + data->id = pdev->id; + data->da903x_dev = pdev->dev.parent; + data->current_brightness = 0; + + /* adjust the WLED output current */ + if (pdata) + da903x_write(data->da903x_dev, DA9034_WLED_CONTROL2, + DA9034_WLED_ISET(pdata->output_current)); + + memset(&props, 0, sizeof(props)); + props.type = BACKLIGHT_RAW; + props.max_brightness = max_brightness; + bl = devm_backlight_device_register(&pdev->dev, pdev->name, + data->da903x_dev, data, + &da903x_backlight_ops, &props); + if (IS_ERR(bl)) { + dev_err(&pdev->dev, "failed to register backlight\n"); + return PTR_ERR(bl); + } + + bl->props.brightness = max_brightness; + + platform_set_drvdata(pdev, bl); + backlight_update_status(bl); + return 0; +} + +static struct platform_driver da903x_backlight_driver = { + .driver = { + .name = "da903x-backlight", + }, + .probe = da903x_backlight_probe, +}; + +module_platform_driver(da903x_backlight_driver); + +MODULE_DESCRIPTION("Backlight Driver for Dialog Semiconductor DA9030/DA9034"); +MODULE_AUTHOR("Eric Miao <eric.miao@marvell.com>"); +MODULE_AUTHOR("Mike Rapoport <mike@compulab.co.il>"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:da903x-backlight"); |