summaryrefslogtreecommitdiffstats
path: root/drivers/video/backlight/lm3533_bl.c
blob: 1d1dbfb789e3aed24628126c748074daef596932 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
/*
 * lm3533-bl.c -- LM3533 Backlight driver
 *
 * Copyright (C) 2011-2012 Texas Instruments
 *
 * Author: Johan Hovold <jhovold@gmail.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under  the terms of the GNU General  Public License as published by the
 * Free Software Foundation;  either version 2 of the License, or (at your
 * option) any later version.
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/backlight.h>
#include <linux/fb.h>
#include <linux/slab.h>

#include <linux/mfd/lm3533.h>


#define LM3533_HVCTRLBANK_COUNT		2
#define LM3533_BL_MAX_BRIGHTNESS	255

#define LM3533_REG_CTRLBANK_AB_BCONF	0x1a


struct lm3533_bl {
	struct lm3533 *lm3533;
	struct lm3533_ctrlbank cb;
	struct backlight_device *bd;
	int id;
};


static inline int lm3533_bl_get_ctrlbank_id(struct lm3533_bl *bl)
{
	return bl->id;
}

static int lm3533_bl_update_status(struct backlight_device *bd)
{
	struct lm3533_bl *bl = bl_get_data(bd);
	int brightness = bd->props.brightness;

	if (bd->props.power != FB_BLANK_UNBLANK)
		brightness = 0;
	if (bd->props.fb_blank != FB_BLANK_UNBLANK)
		brightness = 0;

	return lm3533_ctrlbank_set_brightness(&bl->cb, (u8)brightness);
}

static int lm3533_bl_get_brightness(struct backlight_device *bd)
{
	struct lm3533_bl *bl = bl_get_data(bd);
	u8 val;
	int ret;

	ret = lm3533_ctrlbank_get_brightness(&bl->cb, &val);
	if (ret)
		return ret;

	return val;
}

static const struct backlight_ops lm3533_bl_ops = {
	.get_brightness	= lm3533_bl_get_brightness,
	.update_status	= lm3533_bl_update_status,
};

static ssize_t show_id(struct device *dev,
				struct device_attribute *attr, char *buf)
{
	struct lm3533_bl *bl = dev_get_drvdata(dev);

	return scnprintf(buf, PAGE_SIZE, "%d\n", bl->id);
}

static ssize_t show_als_channel(struct device *dev,
				struct device_attribute *attr, char *buf)
{
	struct lm3533_bl *bl = dev_get_drvdata(dev);
	unsigned channel = lm3533_bl_get_ctrlbank_id(bl);

	return scnprintf(buf, PAGE_SIZE, "%u\n", channel);
}

static ssize_t show_als_en(struct device *dev,
				struct device_attribute *attr, char *buf)
{
	struct lm3533_bl *bl = dev_get_drvdata(dev);
	int ctrlbank = lm3533_bl_get_ctrlbank_id(bl);
	u8 val;
	u8 mask;
	bool enable;
	int ret;

	ret = lm3533_read(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, &val);
	if (ret)
		return ret;

	mask = 1 << (2 * ctrlbank);
	enable = val & mask;

	return scnprintf(buf, PAGE_SIZE, "%d\n", enable);
}

static ssize_t store_als_en(struct device *dev,
					struct device_attribute *attr,
					const char *buf, size_t len)
{
	struct lm3533_bl *bl = dev_get_drvdata(dev);
	int ctrlbank = lm3533_bl_get_ctrlbank_id(bl);
	int enable;
	u8 val;
	u8 mask;
	int ret;

	if (kstrtoint(buf, 0, &enable))
		return -EINVAL;

	mask = 1 << (2 * ctrlbank);

	if (enable)
		val = mask;
	else
		val = 0;

	ret = lm3533_update(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, val,
									mask);
	if (ret)
		return ret;

	return len;
}

static ssize_t show_linear(struct device *dev,
				struct device_attribute *attr, char *buf)
{
	struct lm3533_bl *bl = dev_get_drvdata(dev);
	u8 val;
	u8 mask;
	int linear;
	int ret;

	ret = lm3533_read(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, &val);
	if (ret)
		return ret;

	mask = 1 << (2 * lm3533_bl_get_ctrlbank_id(bl) + 1);

	if (val & mask)
		linear = 1;
	else
		linear = 0;

	return scnprintf(buf, PAGE_SIZE, "%x\n", linear);
}

static ssize_t store_linear(struct device *dev,
					struct device_attribute *attr,
					const char *buf, size_t len)
{
	struct lm3533_bl *bl = dev_get_drvdata(dev);
	unsigned long linear;
	u8 mask;
	u8 val;
	int ret;

	if (kstrtoul(buf, 0, &linear))
		return -EINVAL;

	mask = 1 << (2 * lm3533_bl_get_ctrlbank_id(bl) + 1);

	if (linear)
		val = mask;
	else
		val = 0;

	ret = lm3533_update(bl->lm3533, LM3533_REG_CTRLBANK_AB_BCONF, val,
									mask);
	if (ret)
		return ret;

	return len;
}

static ssize_t show_pwm(struct device *dev,
					struct device_attribute *attr,
					char *buf)
{
	struct lm3533_bl *bl = dev_get_drvdata(dev);
	u8 val;
	int ret;

	ret = lm3533_ctrlbank_get_pwm(&bl->cb, &val);
	if (ret)
		return ret;

	return scnprintf(buf, PAGE_SIZE, "%u\n", val);
}

static ssize_t store_pwm(struct device *dev,
					struct device_attribute *attr,
					const char *buf, size_t len)
{
	struct lm3533_bl *bl = dev_get_drvdata(dev);
	u8 val;
	int ret;

	if (kstrtou8(buf, 0, &val))
		return -EINVAL;

	ret = lm3533_ctrlbank_set_pwm(&bl->cb, val);
	if (ret)
		return ret;

	return len;
}

static LM3533_ATTR_RO(als_channel);
static LM3533_ATTR_RW(als_en);
static LM3533_ATTR_RO(id);
static LM3533_ATTR_RW(linear);
static LM3533_ATTR_RW(pwm);

static struct attribute *lm3533_bl_attributes[] = {
	&dev_attr_als_channel.attr,
	&dev_attr_als_en.attr,
	&dev_attr_id.attr,
	&dev_attr_linear.attr,
	&dev_attr_pwm.attr,
	NULL,
};

static umode_t lm3533_bl_attr_is_visible(struct kobject *kobj,
					     struct attribute *attr, int n)
{
	struct device *dev = container_of(kobj, struct device, kobj);
	struct lm3533_bl *bl = dev_get_drvdata(dev);
	umode_t mode = attr->mode;

	if (attr == &dev_attr_als_channel.attr ||
					attr == &dev_attr_als_en.attr) {
		if (!bl->lm3533->have_als)
			mode = 0;
	}

	return mode;
};

static struct attribute_group lm3533_bl_attribute_group = {
	.is_visible	= lm3533_bl_attr_is_visible,
	.attrs		= lm3533_bl_attributes
};

static int lm3533_bl_setup(struct lm3533_bl *bl,
					struct lm3533_bl_platform_data *pdata)
{
	int ret;

	ret = lm3533_ctrlbank_set_max_current(&bl->cb, pdata->max_current);
	if (ret)
		return ret;

	return lm3533_ctrlbank_set_pwm(&bl->cb, pdata->pwm);
}

static int lm3533_bl_probe(struct platform_device *pdev)
{
	struct lm3533 *lm3533;
	struct lm3533_bl_platform_data *pdata;
	struct lm3533_bl *bl;
	struct backlight_device *bd;
	struct backlight_properties props;
	int ret;

	dev_dbg(&pdev->dev, "%s\n", __func__);

	lm3533 = dev_get_drvdata(pdev->dev.parent);
	if (!lm3533)
		return -EINVAL;

	pdata = pdev->dev.platform_data;
	if (!pdata) {
		dev_err(&pdev->dev, "no platform data\n");
		return -EINVAL;
	}

	if (pdev->id < 0 || pdev->id >= LM3533_HVCTRLBANK_COUNT) {
		dev_err(&pdev->dev, "illegal backlight id %d\n", pdev->id);
		return -EINVAL;
	}

	bl = devm_kzalloc(&pdev->dev, sizeof(*bl), GFP_KERNEL);
	if (!bl) {
		dev_err(&pdev->dev,
				"failed to allocate memory for backlight\n");
		return -ENOMEM;
	}

	bl->lm3533 = lm3533;
	bl->id = pdev->id;

	bl->cb.lm3533 = lm3533;
	bl->cb.id = lm3533_bl_get_ctrlbank_id(bl);
	bl->cb.dev = NULL;			/* until registered */

	memset(&props, 0, sizeof(props));
	props.type = BACKLIGHT_RAW;
	props.max_brightness = LM3533_BL_MAX_BRIGHTNESS;
	props.brightness = pdata->default_brightness;
	bd = backlight_device_register(pdata->name, pdev->dev.parent, bl,
						&lm3533_bl_ops, &props);
	if (IS_ERR(bd)) {
		dev_err(&pdev->dev, "failed to register backlight device\n");
		return PTR_ERR(bd);
	}

	bl->bd = bd;
	bl->cb.dev = &bl->bd->dev;

	platform_set_drvdata(pdev, bl);

	ret = sysfs_create_group(&bd->dev.kobj, &lm3533_bl_attribute_group);
	if (ret < 0) {
		dev_err(&pdev->dev, "failed to create sysfs attributes\n");
		goto err_unregister;
	}

	backlight_update_status(bd);

	ret = lm3533_bl_setup(bl, pdata);
	if (ret)
		goto err_sysfs_remove;

	ret = lm3533_ctrlbank_enable(&bl->cb);
	if (ret)
		goto err_sysfs_remove;

	return 0;

err_sysfs_remove:
	sysfs_remove_group(&bd->dev.kobj, &lm3533_bl_attribute_group);
err_unregister:
	backlight_device_unregister(bd);

	return ret;
}

static int lm3533_bl_remove(struct platform_device *pdev)
{
	struct lm3533_bl *bl = platform_get_drvdata(pdev);
	struct backlight_device *bd = bl->bd;

	dev_dbg(&bd->dev, "%s\n", __func__);

	bd->props.power = FB_BLANK_POWERDOWN;
	bd->props.brightness = 0;

	lm3533_ctrlbank_disable(&bl->cb);
	sysfs_remove_group(&bd->dev.kobj, &lm3533_bl_attribute_group);
	backlight_device_unregister(bd);

	return 0;
}

#ifdef CONFIG_PM_SLEEP
static int lm3533_bl_suspend(struct device *dev)
{
	struct lm3533_bl *bl = dev_get_drvdata(dev);

	dev_dbg(dev, "%s\n", __func__);

	return lm3533_ctrlbank_disable(&bl->cb);
}

static int lm3533_bl_resume(struct device *dev)
{
	struct lm3533_bl *bl = dev_get_drvdata(dev);

	dev_dbg(dev, "%s\n", __func__);

	return lm3533_ctrlbank_enable(&bl->cb);
}
#endif

static SIMPLE_DEV_PM_OPS(lm3533_bl_pm_ops, lm3533_bl_suspend, lm3533_bl_resume);

static void lm3533_bl_shutdown(struct platform_device *pdev)
{
	struct lm3533_bl *bl = platform_get_drvdata(pdev);

	dev_dbg(&pdev->dev, "%s\n", __func__);

	lm3533_ctrlbank_disable(&bl->cb);
}

static struct platform_driver lm3533_bl_driver = {
	.driver = {
		.name	= "lm3533-backlight",
		.owner	= THIS_MODULE,
		.pm	= &lm3533_bl_pm_ops,
	},
	.probe		= lm3533_bl_probe,
	.remove		= lm3533_bl_remove,
	.shutdown	= lm3533_bl_shutdown,
};
module_platform_driver(lm3533_bl_driver);

MODULE_AUTHOR("Johan Hovold <jhovold@gmail.com>");
MODULE_DESCRIPTION("LM3533 Backlight driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:lm3533-backlight");