drivers/video/backlight/da903x_bl.c

Source file repositories/reference/linux-study-clean/drivers/video/backlight/da903x_bl.c

File Facts

System
Linux kernel
Corpus path
drivers/video/backlight/da903x_bl.c
Extension
.c
Size
4057 bytes
Lines
161
Domain
Driver Families
Bucket
drivers/video
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

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)
{
	return da903x_backlight_set(bl, backlight_get_brightness(bl));
}

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;

Annotation

Implementation Notes