1 // SPDX-License-Identifier: GPL-2.0-only
22 #define LWX_FREQ(x)		(((x - 601) / 100) & 0x7)
32 static int max8925_backlight_set(struct backlight_device *bl, int brightness)  in max8925_backlight_set()  argument
34 	struct max8925_backlight_data *data = bl_get_data(bl);  in max8925_backlight_set()
35 	struct max8925_chip *chip = data->chip;  in max8925_backlight_set()
44 	ret = max8925_reg_write(chip->i2c, data->reg_cntl, value);  in max8925_backlight_set()
48 	if (!data->current_brightness && brightness)  in max8925_backlight_set()
50 		ret = max8925_set_bits(chip->i2c, data->reg_mode_cntl, 1, 1);  in max8925_backlight_set()
53 		ret = max8925_set_bits(chip->i2c, data->reg_mode_cntl, 1, 0);  in max8925_backlight_set()
56 	dev_dbg(chip->dev, "set brightness %d\n", value);  in max8925_backlight_set()
57 	data->current_brightness = value;  in max8925_backlight_set()
60 	dev_dbg(chip->dev, "set brightness %d failure with return value:%d\n",  in max8925_backlight_set()
65 static int max8925_backlight_update_status(struct backlight_device *bl)  in max8925_backlight_update_status()  argument
67 	return max8925_backlight_set(bl, backlight_get_brightness(bl));  in max8925_backlight_update_status()
70 static int max8925_backlight_get_brightness(struct backlight_device *bl)  in max8925_backlight_get_brightness()  argument
72 	struct max8925_backlight_data *data = bl_get_data(bl);  in max8925_backlight_get_brightness()
73 	struct max8925_chip *chip = data->chip;  in max8925_backlight_get_brightness()
76 	ret = max8925_reg_read(chip->i2c, data->reg_cntl);  in max8925_backlight_get_brightness()
78 		return -EINVAL;  in max8925_backlight_get_brightness()
79 	data->current_brightness = ret;  in max8925_backlight_get_brightness()
80 	dev_dbg(chip->dev, "get brightness %d\n", data->current_brightness);  in max8925_backlight_get_brightness()
92 	struct device_node *nproot = pdev->dev.parent->of_node, *np;  in max8925_backlight_dt_init()
99 	pdata = devm_kzalloc(&pdev->dev,  in max8925_backlight_dt_init()
107 		dev_err(&pdev->dev, "failed to find backlight node\n");  in max8925_backlight_dt_init()
111 	if (!of_property_read_u32(np, "maxim,max8925-dual-string", &val))  in max8925_backlight_dt_init()
112 		pdata->dual_string = val;  in max8925_backlight_dt_init()
116 	pdev->dev.platform_data = pdata;  in max8925_backlight_dt_init()
121 	struct max8925_chip *chip = dev_get_drvdata(pdev->dev.parent);  in max8925_backlight_probe()
124 	struct backlight_device *bl;  in max8925_backlight_probe()  local
130 	data = devm_kzalloc(&pdev->dev, sizeof(struct max8925_backlight_data),  in max8925_backlight_probe()
133 		return -ENOMEM;  in max8925_backlight_probe()
137 		dev_err(&pdev->dev, "No REG resource for mode control!\n");  in max8925_backlight_probe()
138 		return -ENXIO;  in max8925_backlight_probe()
140 	data->reg_mode_cntl = res->start;  in max8925_backlight_probe()
143 		dev_err(&pdev->dev, "No REG resource for control!\n");  in max8925_backlight_probe()
144 		return -ENXIO;  in max8925_backlight_probe()
146 	data->reg_cntl = res->start;  in max8925_backlight_probe()
148 	data->chip = chip;  in max8925_backlight_probe()
149 	data->current_brightness = 0;  in max8925_backlight_probe()
154 	bl = devm_backlight_device_register(&pdev->dev, "max8925-backlight",  in max8925_backlight_probe()
155 					&pdev->dev, data,  in max8925_backlight_probe()
157 	if (IS_ERR(bl)) {  in max8925_backlight_probe()
158 		dev_err(&pdev->dev, "failed to register backlight\n");  in max8925_backlight_probe()
159 		return PTR_ERR(bl);  in max8925_backlight_probe()
161 	bl->props.brightness = MAX_BRIGHTNESS;  in max8925_backlight_probe()
163 	platform_set_drvdata(pdev, bl);  in max8925_backlight_probe()
166 	if (!pdev->dev.platform_data)  in max8925_backlight_probe()
169 	pdata = pdev->dev.platform_data;  in max8925_backlight_probe()
171 		if (pdata->lxw_scl)  in max8925_backlight_probe()
173 		if (pdata->lxw_freq)  in max8925_backlight_probe()
174 			value |= (LWX_FREQ(pdata->lxw_freq) << 4);  in max8925_backlight_probe()
175 		if (pdata->dual_string)  in max8925_backlight_probe()
178 	ret = max8925_set_bits(chip->i2c, data->reg_mode_cntl, 0xfe, value);  in max8925_backlight_probe()
181 	backlight_update_status(bl);  in max8925_backlight_probe()
187 		.name	= "max8925-backlight",
197 MODULE_ALIAS("platform:max8925-backlight");