1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Backlight driver for Analog Devices ADP5520/ADP5501 MFD PMICs
4  *
5  * Copyright 2009 Analog Devices Inc.
6  */
7 
8 #include <linux/kernel.h>
9 #include <linux/init.h>
10 #include <linux/platform_device.h>
11 #include <linux/fb.h>
12 #include <linux/backlight.h>
13 #include <linux/mfd/adp5520.h>
14 #include <linux/slab.h>
15 #include <linux/module.h>
16 
17 struct adp5520_bl {
18 	struct device *master;
19 	struct adp5520_backlight_platform_data *pdata;
20 	struct mutex lock;
21 	unsigned long cached_daylight_max;
22 	int id;
23 	int current_brightness;
24 };
25 
adp5520_bl_set(struct backlight_device * bl,int brightness)26 static int adp5520_bl_set(struct backlight_device *bl, int brightness)
27 {
28 	struct adp5520_bl *data = bl_get_data(bl);
29 	struct device *master = data->master;
30 	int ret = 0;
31 
32 	if (data->pdata->en_ambl_sens) {
33 		if ((brightness > 0) && (brightness < ADP5020_MAX_BRIGHTNESS)) {
34 			/* Disable Ambient Light auto adjust */
35 			ret |= adp5520_clr_bits(master, ADP5520_BL_CONTROL,
36 					ADP5520_BL_AUTO_ADJ);
37 			ret |= adp5520_write(master, ADP5520_DAYLIGHT_MAX,
38 					brightness);
39 		} else {
40 			/*
41 			 * MAX_BRIGHTNESS -> Enable Ambient Light auto adjust
42 			 * restore daylight l3 sysfs brightness
43 			 */
44 			ret |= adp5520_write(master, ADP5520_DAYLIGHT_MAX,
45 					 data->cached_daylight_max);
46 			ret |= adp5520_set_bits(master, ADP5520_BL_CONTROL,
47 					 ADP5520_BL_AUTO_ADJ);
48 		}
49 	} else {
50 		ret |= adp5520_write(master, ADP5520_DAYLIGHT_MAX, brightness);
51 	}
52 
53 	if (data->current_brightness && brightness == 0)
54 		ret |= adp5520_set_bits(master,
55 				ADP5520_MODE_STATUS, ADP5520_DIM_EN);
56 	else if (data->current_brightness == 0 && brightness)
57 		ret |= adp5520_clr_bits(master,
58 				ADP5520_MODE_STATUS, ADP5520_DIM_EN);
59 
60 	if (!ret)
61 		data->current_brightness = brightness;
62 
63 	return ret;
64 }
65 
adp5520_bl_update_status(struct backlight_device * bl)66 static int adp5520_bl_update_status(struct backlight_device *bl)
67 {
68 	return adp5520_bl_set(bl, backlight_get_brightness(bl));
69 }
70 
adp5520_bl_get_brightness(struct backlight_device * bl)71 static int adp5520_bl_get_brightness(struct backlight_device *bl)
72 {
73 	struct adp5520_bl *data = bl_get_data(bl);
74 	int error;
75 	uint8_t reg_val;
76 
77 	error = adp5520_read(data->master, ADP5520_BL_VALUE, &reg_val);
78 
79 	return error ? data->current_brightness : reg_val;
80 }
81 
82 static const struct backlight_ops adp5520_bl_ops = {
83 	.update_status	= adp5520_bl_update_status,
84 	.get_brightness	= adp5520_bl_get_brightness,
85 };
86 
adp5520_bl_setup(struct backlight_device * bl)87 static int adp5520_bl_setup(struct backlight_device *bl)
88 {
89 	struct adp5520_bl *data = bl_get_data(bl);
90 	struct device *master = data->master;
91 	struct adp5520_backlight_platform_data *pdata = data->pdata;
92 	int ret = 0;
93 
94 	ret |= adp5520_write(master, ADP5520_DAYLIGHT_MAX,
95 				pdata->l1_daylight_max);
96 	ret |= adp5520_write(master, ADP5520_DAYLIGHT_DIM,
97 				pdata->l1_daylight_dim);
98 
99 	if (pdata->en_ambl_sens) {
100 		data->cached_daylight_max = pdata->l1_daylight_max;
101 		ret |= adp5520_write(master, ADP5520_OFFICE_MAX,
102 				pdata->l2_office_max);
103 		ret |= adp5520_write(master, ADP5520_OFFICE_DIM,
104 				pdata->l2_office_dim);
105 		ret |= adp5520_write(master, ADP5520_DARK_MAX,
106 				pdata->l3_dark_max);
107 		ret |= adp5520_write(master, ADP5520_DARK_DIM,
108 				pdata->l3_dark_dim);
109 		ret |= adp5520_write(master, ADP5520_L2_TRIP,
110 				pdata->l2_trip);
111 		ret |= adp5520_write(master, ADP5520_L2_HYS,
112 				pdata->l2_hyst);
113 		ret |= adp5520_write(master, ADP5520_L3_TRIP,
114 				 pdata->l3_trip);
115 		ret |= adp5520_write(master, ADP5520_L3_HYS,
116 				pdata->l3_hyst);
117 		ret |= adp5520_write(master, ADP5520_ALS_CMPR_CFG,
118 				ALS_CMPR_CFG_VAL(pdata->abml_filt,
119 				ADP5520_L3_EN));
120 	}
121 
122 	ret |= adp5520_write(master, ADP5520_BL_CONTROL,
123 			BL_CTRL_VAL(pdata->fade_led_law,
124 					pdata->en_ambl_sens));
125 
126 	ret |= adp5520_write(master, ADP5520_BL_FADE, FADE_VAL(pdata->fade_in,
127 			pdata->fade_out));
128 
129 	ret |= adp5520_set_bits(master, ADP5520_MODE_STATUS,
130 			ADP5520_BL_EN | ADP5520_DIM_EN);
131 
132 	return ret;
133 }
134 
adp5520_show(struct device * dev,char * buf,int reg)135 static ssize_t adp5520_show(struct device *dev, char *buf, int reg)
136 {
137 	struct adp5520_bl *data = dev_get_drvdata(dev);
138 	int ret;
139 	uint8_t reg_val;
140 
141 	mutex_lock(&data->lock);
142 	ret = adp5520_read(data->master, reg, &reg_val);
143 	mutex_unlock(&data->lock);
144 
145 	if (ret < 0)
146 		return ret;
147 
148 	return sprintf(buf, "%u\n", reg_val);
149 }
150 
adp5520_store(struct device * dev,const char * buf,size_t count,int reg)151 static ssize_t adp5520_store(struct device *dev, const char *buf,
152 			 size_t count, int reg)
153 {
154 	struct adp5520_bl *data = dev_get_drvdata(dev);
155 	unsigned long val;
156 	int ret;
157 
158 	ret = kstrtoul(buf, 10, &val);
159 	if (ret)
160 		return ret;
161 
162 	mutex_lock(&data->lock);
163 	adp5520_write(data->master, reg, val);
164 	mutex_unlock(&data->lock);
165 
166 	return count;
167 }
168 
adp5520_bl_dark_max_show(struct device * dev,struct device_attribute * attr,char * buf)169 static ssize_t adp5520_bl_dark_max_show(struct device *dev,
170 			struct device_attribute *attr, char *buf)
171 {
172 	return adp5520_show(dev, buf, ADP5520_DARK_MAX);
173 }
174 
adp5520_bl_dark_max_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)175 static ssize_t adp5520_bl_dark_max_store(struct device *dev,
176 			struct device_attribute *attr,
177 			const char *buf, size_t count)
178 {
179 	return adp5520_store(dev, buf, count, ADP5520_DARK_MAX);
180 }
181 static DEVICE_ATTR(dark_max, 0664, adp5520_bl_dark_max_show,
182 			adp5520_bl_dark_max_store);
183 
adp5520_bl_office_max_show(struct device * dev,struct device_attribute * attr,char * buf)184 static ssize_t adp5520_bl_office_max_show(struct device *dev,
185 			struct device_attribute *attr, char *buf)
186 {
187 	return adp5520_show(dev, buf, ADP5520_OFFICE_MAX);
188 }
189 
adp5520_bl_office_max_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)190 static ssize_t adp5520_bl_office_max_store(struct device *dev,
191 			struct device_attribute *attr,
192 			const char *buf, size_t count)
193 {
194 	return adp5520_store(dev, buf, count, ADP5520_OFFICE_MAX);
195 }
196 static DEVICE_ATTR(office_max, 0664, adp5520_bl_office_max_show,
197 			adp5520_bl_office_max_store);
198 
adp5520_bl_daylight_max_show(struct device * dev,struct device_attribute * attr,char * buf)199 static ssize_t adp5520_bl_daylight_max_show(struct device *dev,
200 			struct device_attribute *attr, char *buf)
201 {
202 	return adp5520_show(dev, buf, ADP5520_DAYLIGHT_MAX);
203 }
204 
adp5520_bl_daylight_max_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)205 static ssize_t adp5520_bl_daylight_max_store(struct device *dev,
206 			struct device_attribute *attr,
207 			const char *buf, size_t count)
208 {
209 	struct adp5520_bl *data = dev_get_drvdata(dev);
210 	int ret;
211 
212 	ret = kstrtoul(buf, 10, &data->cached_daylight_max);
213 	if (ret < 0)
214 		return ret;
215 
216 	return adp5520_store(dev, buf, count, ADP5520_DAYLIGHT_MAX);
217 }
218 static DEVICE_ATTR(daylight_max, 0664, adp5520_bl_daylight_max_show,
219 			adp5520_bl_daylight_max_store);
220 
adp5520_bl_dark_dim_show(struct device * dev,struct device_attribute * attr,char * buf)221 static ssize_t adp5520_bl_dark_dim_show(struct device *dev,
222 			struct device_attribute *attr, char *buf)
223 {
224 	return adp5520_show(dev, buf, ADP5520_DARK_DIM);
225 }
226 
adp5520_bl_dark_dim_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)227 static ssize_t adp5520_bl_dark_dim_store(struct device *dev,
228 			struct device_attribute *attr,
229 			const char *buf, size_t count)
230 {
231 	return adp5520_store(dev, buf, count, ADP5520_DARK_DIM);
232 }
233 static DEVICE_ATTR(dark_dim, 0664, adp5520_bl_dark_dim_show,
234 			adp5520_bl_dark_dim_store);
235 
adp5520_bl_office_dim_show(struct device * dev,struct device_attribute * attr,char * buf)236 static ssize_t adp5520_bl_office_dim_show(struct device *dev,
237 			struct device_attribute *attr, char *buf)
238 {
239 	return adp5520_show(dev, buf, ADP5520_OFFICE_DIM);
240 }
241 
adp5520_bl_office_dim_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)242 static ssize_t adp5520_bl_office_dim_store(struct device *dev,
243 			struct device_attribute *attr,
244 			const char *buf, size_t count)
245 {
246 	return adp5520_store(dev, buf, count, ADP5520_OFFICE_DIM);
247 }
248 static DEVICE_ATTR(office_dim, 0664, adp5520_bl_office_dim_show,
249 			adp5520_bl_office_dim_store);
250 
adp5520_bl_daylight_dim_show(struct device * dev,struct device_attribute * attr,char * buf)251 static ssize_t adp5520_bl_daylight_dim_show(struct device *dev,
252 			struct device_attribute *attr, char *buf)
253 {
254 	return adp5520_show(dev, buf, ADP5520_DAYLIGHT_DIM);
255 }
256 
adp5520_bl_daylight_dim_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)257 static ssize_t adp5520_bl_daylight_dim_store(struct device *dev,
258 			struct device_attribute *attr,
259 			const char *buf, size_t count)
260 {
261 	return adp5520_store(dev, buf, count, ADP5520_DAYLIGHT_DIM);
262 }
263 static DEVICE_ATTR(daylight_dim, 0664, adp5520_bl_daylight_dim_show,
264 			adp5520_bl_daylight_dim_store);
265 
266 static struct attribute *adp5520_bl_attributes[] = {
267 	&dev_attr_dark_max.attr,
268 	&dev_attr_dark_dim.attr,
269 	&dev_attr_office_max.attr,
270 	&dev_attr_office_dim.attr,
271 	&dev_attr_daylight_max.attr,
272 	&dev_attr_daylight_dim.attr,
273 	NULL
274 };
275 
276 static const struct attribute_group adp5520_bl_attr_group = {
277 	.attrs = adp5520_bl_attributes,
278 };
279 
adp5520_bl_probe(struct platform_device * pdev)280 static int adp5520_bl_probe(struct platform_device *pdev)
281 {
282 	struct backlight_properties props;
283 	struct backlight_device *bl;
284 	struct adp5520_bl *data;
285 	int ret = 0;
286 
287 	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
288 	if (data == NULL)
289 		return -ENOMEM;
290 
291 	data->master = pdev->dev.parent;
292 	data->pdata = dev_get_platdata(&pdev->dev);
293 
294 	if (data->pdata  == NULL) {
295 		dev_err(&pdev->dev, "missing platform data\n");
296 		return -ENODEV;
297 	}
298 
299 	data->id = pdev->id;
300 	data->current_brightness = 0;
301 
302 	mutex_init(&data->lock);
303 
304 	memset(&props, 0, sizeof(struct backlight_properties));
305 	props.type = BACKLIGHT_RAW;
306 	props.max_brightness = ADP5020_MAX_BRIGHTNESS;
307 	bl = devm_backlight_device_register(&pdev->dev, pdev->name,
308 					data->master, data, &adp5520_bl_ops,
309 					&props);
310 	if (IS_ERR(bl)) {
311 		dev_err(&pdev->dev, "failed to register backlight\n");
312 		return PTR_ERR(bl);
313 	}
314 
315 	bl->props.brightness = ADP5020_MAX_BRIGHTNESS;
316 	if (data->pdata->en_ambl_sens)
317 		ret = sysfs_create_group(&bl->dev.kobj,
318 			&adp5520_bl_attr_group);
319 
320 	if (ret) {
321 		dev_err(&pdev->dev, "failed to register sysfs\n");
322 		return ret;
323 	}
324 
325 	platform_set_drvdata(pdev, bl);
326 	ret = adp5520_bl_setup(bl);
327 	if (ret) {
328 		dev_err(&pdev->dev, "failed to setup\n");
329 		if (data->pdata->en_ambl_sens)
330 			sysfs_remove_group(&bl->dev.kobj,
331 					&adp5520_bl_attr_group);
332 		return ret;
333 	}
334 
335 	backlight_update_status(bl);
336 
337 	return 0;
338 }
339 
adp5520_bl_remove(struct platform_device * pdev)340 static int adp5520_bl_remove(struct platform_device *pdev)
341 {
342 	struct backlight_device *bl = platform_get_drvdata(pdev);
343 	struct adp5520_bl *data = bl_get_data(bl);
344 
345 	adp5520_clr_bits(data->master, ADP5520_MODE_STATUS, ADP5520_BL_EN);
346 
347 	if (data->pdata->en_ambl_sens)
348 		sysfs_remove_group(&bl->dev.kobj,
349 				&adp5520_bl_attr_group);
350 
351 	return 0;
352 }
353 
354 #ifdef CONFIG_PM_SLEEP
adp5520_bl_suspend(struct device * dev)355 static int adp5520_bl_suspend(struct device *dev)
356 {
357 	struct backlight_device *bl = dev_get_drvdata(dev);
358 
359 	return adp5520_bl_set(bl, 0);
360 }
361 
adp5520_bl_resume(struct device * dev)362 static int adp5520_bl_resume(struct device *dev)
363 {
364 	struct backlight_device *bl = dev_get_drvdata(dev);
365 
366 	backlight_update_status(bl);
367 	return 0;
368 }
369 #endif
370 
371 static SIMPLE_DEV_PM_OPS(adp5520_bl_pm_ops, adp5520_bl_suspend,
372 			adp5520_bl_resume);
373 
374 static struct platform_driver adp5520_bl_driver = {
375 	.driver		= {
376 		.name	= "adp5520-backlight",
377 		.pm	= &adp5520_bl_pm_ops,
378 	},
379 	.probe		= adp5520_bl_probe,
380 	.remove		= adp5520_bl_remove,
381 };
382 
383 module_platform_driver(adp5520_bl_driver);
384 
385 MODULE_AUTHOR("Michael Hennerich <michael.hennerich@analog.com>");
386 MODULE_DESCRIPTION("ADP5520(01) Backlight Driver");
387 MODULE_LICENSE("GPL");
388 MODULE_ALIAS("platform:adp5520-backlight");
389