1 // SPDX-License-Identifier: GPL-2.0-only
3  * TI LP8788 MFD - backlight driver
10 #include <linux/backlight.h>
15 #include <linux/pwm.h>
32 #define DEFAULT_BL_NAME			"lcd-backlight"
48 	struct pwm_device *pwm;  member
73 	struct lp8788_backlight_platform_data *pdata = bl->pdata;  in lp8788_backlight_configure()
83 		cfg->bl_mode    = pdata->bl_mode;  in lp8788_backlight_configure()
84 		cfg->dim_mode   = pdata->dim_mode;  in lp8788_backlight_configure()
85 		cfg->full_scale = pdata->full_scale;  in lp8788_backlight_configure()
86 		cfg->rise_time  = pdata->rise_time;  in lp8788_backlight_configure()
87 		cfg->fall_time  = pdata->fall_time;  in lp8788_backlight_configure()
88 		cfg->pwm_pol    = pdata->pwm_pol;  in lp8788_backlight_configure()
92 	val = (cfg->rise_time << LP8788_BL_RAMP_RISE_SHIFT) | cfg->fall_time;  in lp8788_backlight_configure()
93 	ret = lp8788_write_byte(bl->lp, LP8788_BL_RAMP, val);  in lp8788_backlight_configure()
98 	val = (cfg->full_scale << LP8788_BL_FULLSCALE_SHIFT) |  in lp8788_backlight_configure()
99 		(cfg->dim_mode << LP8788_BL_DIM_MODE_SHIFT);  in lp8788_backlight_configure()
102 	switch (cfg->bl_mode) {  in lp8788_backlight_configure()
109 			(cfg->pwm_pol << LP8788_BL_PWM_POLARITY_SHIFT);  in lp8788_backlight_configure()
112 		dev_err(bl->lp->dev, "invalid mode: %d\n", cfg->bl_mode);  in lp8788_backlight_configure()
113 		return -EINVAL;  in lp8788_backlight_configure()
116 	bl->mode = cfg->bl_mode;  in lp8788_backlight_configure()
118 	return lp8788_write_byte(bl->lp, LP8788_BL_CONFIG, val);  in lp8788_backlight_configure()
126 	struct pwm_device *pwm;  in lp8788_pwm_ctrl()  local
128 	if (!bl->pdata)  in lp8788_pwm_ctrl()
131 	period = bl->pdata->period_ns;  in lp8788_pwm_ctrl()
133 	dev = bl->lp->dev;  in lp8788_pwm_ctrl()
135 	/* request PWM device with the consumer name */  in lp8788_pwm_ctrl()
136 	if (!bl->pwm) {  in lp8788_pwm_ctrl()
137 		pwm = devm_pwm_get(dev, LP8788_DEV_BACKLIGHT);  in lp8788_pwm_ctrl()
138 		if (IS_ERR(pwm)) {  in lp8788_pwm_ctrl()
139 			dev_err(dev, "can not get PWM device\n");  in lp8788_pwm_ctrl()
143 		bl->pwm = pwm;  in lp8788_pwm_ctrl()
147 		 * the atomic PWM API.  in lp8788_pwm_ctrl()
149 		pwm_apply_args(pwm);  in lp8788_pwm_ctrl()
152 	pwm_config(bl->pwm, duty, period);  in lp8788_pwm_ctrl()
154 		pwm_enable(bl->pwm);  in lp8788_pwm_ctrl()
156 		pwm_disable(bl->pwm);  in lp8788_pwm_ctrl()
162 	enum lp8788_bl_ctrl_mode mode = bl->mode;  in lp8788_bl_update_status()
164 	if (bl_dev->props.state & BL_CORE_SUSPENDED)  in lp8788_bl_update_status()
165 		bl_dev->props.brightness = 0;  in lp8788_bl_update_status()
168 		int brt = bl_dev->props.brightness;  in lp8788_bl_update_status()
169 		int max = bl_dev->props.max_brightness;  in lp8788_bl_update_status()
173 		u8 brt = bl_dev->props.brightness;  in lp8788_bl_update_status()
175 		lp8788_write_byte(bl->lp, LP8788_BL_BRIGHTNESS, brt);  in lp8788_bl_update_status()
190 	struct lp8788_backlight_platform_data *pdata = bl->pdata;  in lp8788_backlight_register()
199 		init_brt = min_t(int, pdata->initial_brightness,  in lp8788_backlight_register()
206 	/* Backlight device name */  in lp8788_backlight_register()
207 	if (!pdata || !pdata->name)  in lp8788_backlight_register()
210 		name = pdata->name;  in lp8788_backlight_register()
212 	bl_dev = backlight_device_register(name, bl->lp->dev, bl,  in lp8788_backlight_register()
217 	bl->bl_dev = bl_dev;  in lp8788_backlight_register()
224 	struct backlight_device *bl_dev = bl->bl_dev;  in lp8788_backlight_unregister()
233 	enum lp8788_bl_ctrl_mode mode = bl->mode;  in lp8788_get_bl_ctl_mode()
237 		strmode = "PWM based";  in lp8788_get_bl_ctl_mode()
259 	struct lp8788 *lp = dev_get_drvdata(pdev->dev.parent);  in lp8788_backlight_probe()
263 	bl = devm_kzalloc(lp->dev, sizeof(struct lp8788_bl), GFP_KERNEL);  in lp8788_backlight_probe()
265 		return -ENOMEM;  in lp8788_backlight_probe()
267 	bl->lp = lp;  in lp8788_backlight_probe()
268 	if (lp->pdata)  in lp8788_backlight_probe()
269 		bl->pdata = lp->pdata->bl_pdata;  in lp8788_backlight_probe()
275 		dev_err(lp->dev, "backlight config err: %d\n", ret);  in lp8788_backlight_probe()
281 		dev_err(lp->dev, "register backlight err: %d\n", ret);  in lp8788_backlight_probe()
285 	ret = sysfs_create_group(&pdev->dev.kobj, &lp8788_attr_group);  in lp8788_backlight_probe()
287 		dev_err(lp->dev, "register sysfs err: %d\n", ret);  in lp8788_backlight_probe()
291 	backlight_update_status(bl->bl_dev);  in lp8788_backlight_probe()
304 	struct backlight_device *bl_dev = bl->bl_dev;  in lp8788_backlight_remove()
306 	bl_dev->props.brightness = 0;  in lp8788_backlight_remove()
308 	sysfs_remove_group(&pdev->dev.kobj, &lp8788_attr_group);  in lp8788_backlight_remove()
323 MODULE_DESCRIPTION("Texas Instruments LP8788 Backlight Driver");
326 MODULE_ALIAS("platform:lp8788-backlight");