summaryrefslogtreecommitdiff
path: root/drivers/media/i2c/lm3646.c
blob: ba5ee0d7a78e8bc86505c0046bf1869f920cf032 (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
/*
 * drivers/media/i2c/lm3646.c
 * General device driver for TI lm3646, Dual FLASH LED Driver
 *
 * Copyright (C) 2014 Texas Instruments
 *
 * Contact: Daniel Jeong <gshark.jeong@gmail.com>
 *			Ldd-Mlp <ldd-mlp@list.ti.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 */

#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/regmap.h>
#include <linux/videodev2.h>
#include <media/i2c/lm3646.h>
#include <media/v4l2-ctrls.h>
#include <media/v4l2-device.h>

/* registers definitions */
#define REG_ENABLE		0x01
#define REG_TORCH_BR	0x05
#define REG_FLASH_BR	0x05
#define REG_FLASH_TOUT	0x04
#define REG_FLAG		0x08
#define REG_STROBE_SRC	0x06
#define REG_LED1_FLASH_BR 0x06
#define REG_LED1_TORCH_BR 0x07

#define MASK_ENABLE		0x03
#define MASK_TORCH_BR	0x70
#define MASK_FLASH_BR	0x0F
#define MASK_FLASH_TOUT	0x07
#define MASK_FLAG		0xFF
#define MASK_STROBE_SRC	0x80

/* Fault Mask */
#define FAULT_TIMEOUT	(1<<0)
#define FAULT_SHORT_CIRCUIT	(1<<1)
#define FAULT_UVLO		(1<<2)
#define FAULT_IVFM		(1<<3)
#define FAULT_OCP		(1<<4)
#define FAULT_OVERTEMP	(1<<5)
#define FAULT_NTC_TRIP	(1<<6)
#define FAULT_OVP		(1<<7)

enum led_mode {
	MODE_SHDN = 0x0,
	MODE_TORCH = 0x2,
	MODE_FLASH = 0x3,
};

/*
 * struct lm3646_flash
 *
 * @pdata: platform data
 * @regmap: reg. map for i2c
 * @lock: muxtex for serial access.
 * @led_mode: V4L2 LED mode
 * @ctrls_led: V4L2 contols
 * @subdev_led: V4L2 subdev
 * @mode_reg : mode register value
 */
struct lm3646_flash {
	struct device *dev;
	struct lm3646_platform_data *pdata;
	struct regmap *regmap;

	struct v4l2_ctrl_handler ctrls_led;
	struct v4l2_subdev subdev_led;

	u8 mode_reg;
};

#define to_lm3646_flash(_ctrl)	\
	container_of(_ctrl->handler, struct lm3646_flash, ctrls_led)

/* enable mode control */
static int lm3646_mode_ctrl(struct lm3646_flash *flash,
			    enum v4l2_flash_led_mode led_mode)
{
	switch (led_mode) {
	case V4L2_FLASH_LED_MODE_NONE:
		return regmap_write(flash->regmap,
				    REG_ENABLE, flash->mode_reg | MODE_SHDN);
	case V4L2_FLASH_LED_MODE_TORCH:
		return regmap_write(flash->regmap,
				    REG_ENABLE, flash->mode_reg | MODE_TORCH);
	case V4L2_FLASH_LED_MODE_FLASH:
		return regmap_write(flash->regmap,
				    REG_ENABLE, flash->mode_reg | MODE_FLASH);
	}
	return -EINVAL;
}

/* V4L2 controls  */
static int lm3646_get_ctrl(struct v4l2_ctrl *ctrl)
{
	struct lm3646_flash *flash = to_lm3646_flash(ctrl);
	unsigned int reg_val;
	int rval;

	if (ctrl->id != V4L2_CID_FLASH_FAULT)
		return -EINVAL;

	rval = regmap_read(flash->regmap, REG_FLAG, &reg_val);
	if (rval < 0)
		return rval;

	ctrl->val = 0;
	if (reg_val & FAULT_TIMEOUT)
		ctrl->val |= V4L2_FLASH_FAULT_TIMEOUT;
	if (reg_val & FAULT_SHORT_CIRCUIT)
		ctrl->val |= V4L2_FLASH_FAULT_SHORT_CIRCUIT;
	if (reg_val & FAULT_UVLO)
		ctrl->val |= V4L2_FLASH_FAULT_UNDER_VOLTAGE;
	if (reg_val & FAULT_IVFM)
		ctrl->val |= V4L2_FLASH_FAULT_INPUT_VOLTAGE;
	if (reg_val & FAULT_OCP)
		ctrl->val |= V4L2_FLASH_FAULT_OVER_CURRENT;
	if (reg_val & FAULT_OVERTEMP)
		ctrl->val |= V4L2_FLASH_FAULT_OVER_TEMPERATURE;
	if (reg_val & FAULT_NTC_TRIP)
		ctrl->val |= V4L2_FLASH_FAULT_LED_OVER_TEMPERATURE;
	if (reg_val & FAULT_OVP)
		ctrl->val |= V4L2_FLASH_FAULT_OVER_VOLTAGE;

	return 0;
}

static int lm3646_set_ctrl(struct v4l2_ctrl *ctrl)
{
	struct lm3646_flash *flash = to_lm3646_flash(ctrl);
	unsigned int reg_val;
	int rval = -EINVAL;

	switch (ctrl->id) {
	case V4L2_CID_FLASH_LED_MODE:

		if (ctrl->val != V4L2_FLASH_LED_MODE_FLASH)
			return lm3646_mode_ctrl(flash, ctrl->val);
		/* switch to SHDN mode before flash strobe on */
		return lm3646_mode_ctrl(flash, V4L2_FLASH_LED_MODE_NONE);

	case V4L2_CID_FLASH_STROBE_SOURCE:
		return regmap_update_bits(flash->regmap,
					  REG_STROBE_SRC, MASK_STROBE_SRC,
					  (ctrl->val) << 7);

	case V4L2_CID_FLASH_STROBE:

		/* read and check current mode of chip to start flash */
		rval = regmap_read(flash->regmap, REG_ENABLE, &reg_val);
		if (rval < 0 || ((reg_val & MASK_ENABLE) != MODE_SHDN))
			return rval;
		/* flash on */
		return lm3646_mode_ctrl(flash, V4L2_FLASH_LED_MODE_FLASH);

	case V4L2_CID_FLASH_STROBE_STOP:

		/*
		 * flash mode will be turned automatically
		 * from FLASH mode to SHDN mode after flash duration timeout
		 * read and check current mode of chip to stop flash
		 */
		rval = regmap_read(flash->regmap, REG_ENABLE, &reg_val);
		if (rval < 0)
			return rval;
		if ((reg_val & MASK_ENABLE) == MODE_FLASH)
			return lm3646_mode_ctrl(flash,
						V4L2_FLASH_LED_MODE_NONE);
		return rval;

	case V4L2_CID_FLASH_TIMEOUT:
		return regmap_update_bits(flash->regmap,
					  REG_FLASH_TOUT, MASK_FLASH_TOUT,
					  LM3646_FLASH_TOUT_ms_TO_REG
					  (ctrl->val));

	case V4L2_CID_FLASH_INTENSITY:
		return regmap_update_bits(flash->regmap,
					  REG_FLASH_BR, MASK_FLASH_BR,
					  LM3646_TOTAL_FLASH_BRT_uA_TO_REG
					  (ctrl->val));

	case V4L2_CID_FLASH_TORCH_INTENSITY:
		return regmap_update_bits(flash->regmap,
					  REG_TORCH_BR, MASK_TORCH_BR,
					  LM3646_TOTAL_TORCH_BRT_uA_TO_REG
					  (ctrl->val) << 4);
	}

	return -EINVAL;
}

static const struct v4l2_ctrl_ops lm3646_led_ctrl_ops = {
	.g_volatile_ctrl = lm3646_get_ctrl,
	.s_ctrl = lm3646_set_ctrl,
};

static int lm3646_init_controls(struct lm3646_flash *flash)
{
	struct v4l2_ctrl *fault;
	struct v4l2_ctrl_handler *hdl = &flash->ctrls_led;
	const struct v4l2_ctrl_ops *ops = &lm3646_led_ctrl_ops;

	v4l2_ctrl_handler_init(hdl, 8);
	/* flash mode */
	v4l2_ctrl_new_std_menu(hdl, ops, V4L2_CID_FLASH_LED_MODE,
			       V4L2_FLASH_LED_MODE_TORCH, ~0x7,
			       V4L2_FLASH_LED_MODE_NONE);

	/* flash source */
	v4l2_ctrl_new_std_menu(hdl, ops, V4L2_CID_FLASH_STROBE_SOURCE,
			       0x1, ~0x3, V4L2_FLASH_STROBE_SOURCE_SOFTWARE);

	/* flash strobe */
	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_STROBE, 0, 0, 0, 0);
	/* flash strobe stop */
	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_STROBE_STOP, 0, 0, 0, 0);

	/* flash strobe timeout */
	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_TIMEOUT,
			  LM3646_FLASH_TOUT_MIN,
			  LM3646_FLASH_TOUT_MAX,
			  LM3646_FLASH_TOUT_STEP, flash->pdata->flash_timeout);

	/* max flash current */
	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_INTENSITY,
			  LM3646_TOTAL_FLASH_BRT_MIN,
			  LM3646_TOTAL_FLASH_BRT_MAX,
			  LM3646_TOTAL_FLASH_BRT_STEP,
			  LM3646_TOTAL_FLASH_BRT_MAX);

	/* max torch current */
	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_TORCH_INTENSITY,
			  LM3646_TOTAL_TORCH_BRT_MIN,
			  LM3646_TOTAL_TORCH_BRT_MAX,
			  LM3646_TOTAL_TORCH_BRT_STEP,
			  LM3646_TOTAL_TORCH_BRT_MAX);

	/* fault */
	fault = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_FAULT, 0,
				  V4L2_FLASH_FAULT_OVER_VOLTAGE
				  | V4L2_FLASH_FAULT_OVER_TEMPERATURE
				  | V4L2_FLASH_FAULT_SHORT_CIRCUIT
				  | V4L2_FLASH_FAULT_TIMEOUT, 0, 0);
	if (fault != NULL)
		fault->flags |= V4L2_CTRL_FLAG_VOLATILE;

	if (hdl->error)
		return hdl->error;

	flash->subdev_led.ctrl_handler = hdl;
	return 0;
}

/* initialize device */
static const struct v4l2_subdev_ops lm3646_ops = {
	.core = NULL,
};

static const struct regmap_config lm3646_regmap = {
	.reg_bits = 8,
	.val_bits = 8,
	.max_register = 0xFF,
};

static int lm3646_subdev_init(struct lm3646_flash *flash)
{
	struct i2c_client *client = to_i2c_client(flash->dev);
	int rval;

	v4l2_i2c_subdev_init(&flash->subdev_led, client, &lm3646_ops);
	flash->subdev_led.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
	strcpy(flash->subdev_led.name, LM3646_NAME);
	rval = lm3646_init_controls(flash);
	if (rval)
		goto err_out;
	rval = media_entity_init(&flash->subdev_led.entity, 0, NULL);
	if (rval < 0)
		goto err_out;
	flash->subdev_led.entity.function = MEDIA_ENT_F_FLASH;
	return rval;

err_out:
	v4l2_ctrl_handler_free(&flash->ctrls_led);
	return rval;
}

static int lm3646_init_device(struct lm3646_flash *flash)
{
	unsigned int reg_val;
	int rval;

	/* read the value of mode register to reduce redundant i2c accesses */
	rval = regmap_read(flash->regmap, REG_ENABLE, &reg_val);
	if (rval < 0)
		return rval;
	flash->mode_reg = reg_val & 0xfc;

	/* output disable */
	rval = lm3646_mode_ctrl(flash, V4L2_FLASH_LED_MODE_NONE);
	if (rval < 0)
		return rval;

	/*
	 * LED1 flash current setting
	 * LED2 flash current = Total(Max) flash current - LED1 flash current
	 */
	rval = regmap_update_bits(flash->regmap,
				  REG_LED1_FLASH_BR, 0x7F,
				  LM3646_LED1_FLASH_BRT_uA_TO_REG
				  (flash->pdata->led1_flash_brt));

	if (rval < 0)
		return rval;

	/*
	 * LED1 torch current setting
	 * LED2 torch current = Total(Max) torch current - LED1 torch current
	 */
	rval = regmap_update_bits(flash->regmap,
				  REG_LED1_TORCH_BR, 0x7F,
				  LM3646_LED1_TORCH_BRT_uA_TO_REG
				  (flash->pdata->led1_torch_brt));
	if (rval < 0)
		return rval;

	/* Reset flag register */
	return regmap_read(flash->regmap, REG_FLAG, &reg_val);
}

static int lm3646_probe(struct i2c_client *client,
			const struct i2c_device_id *devid)
{
	struct lm3646_flash *flash;
	struct lm3646_platform_data *pdata = dev_get_platdata(&client->dev);
	int rval;

	flash = devm_kzalloc(&client->dev, sizeof(*flash), GFP_KERNEL);
	if (flash == NULL)
		return -ENOMEM;

	flash->regmap = devm_regmap_init_i2c(client, &lm3646_regmap);
	if (IS_ERR(flash->regmap))
		return PTR_ERR(flash->regmap);

	/* check device tree if there is no platform data */
	if (pdata == NULL) {
		pdata = devm_kzalloc(&client->dev,
				     sizeof(struct lm3646_platform_data),
				     GFP_KERNEL);
		if (pdata == NULL)
			return -ENOMEM;
		/* use default data in case of no platform data */
		pdata->flash_timeout = LM3646_FLASH_TOUT_MAX;
		pdata->led1_torch_brt = LM3646_LED1_TORCH_BRT_MAX;
		pdata->led1_flash_brt = LM3646_LED1_FLASH_BRT_MAX;
	}
	flash->pdata = pdata;
	flash->dev = &client->dev;

	rval = lm3646_subdev_init(flash);
	if (rval < 0)
		return rval;

	rval = lm3646_init_device(flash);
	if (rval < 0)
		return rval;

	i2c_set_clientdata(client, flash);

	return 0;
}

static int lm3646_remove(struct i2c_client *client)
{
	struct lm3646_flash *flash = i2c_get_clientdata(client);

	v4l2_device_unregister_subdev(&flash->subdev_led);
	v4l2_ctrl_handler_free(&flash->ctrls_led);
	media_entity_cleanup(&flash->subdev_led.entity);

	return 0;
}

static const struct i2c_device_id lm3646_id_table[] = {
	{LM3646_NAME, 0},
	{}
};

MODULE_DEVICE_TABLE(i2c, lm3646_id_table);

static struct i2c_driver lm3646_i2c_driver = {
	.driver = {
		   .name = LM3646_NAME,
		   },
	.probe = lm3646_probe,
	.remove = lm3646_remove,
	.id_table = lm3646_id_table,
};

module_i2c_driver(lm3646_i2c_driver);

MODULE_AUTHOR("Daniel Jeong <gshark.jeong@gmail.com>");
MODULE_AUTHOR("Ldd Mlp <ldd-mlp@list.ti.com>");
MODULE_DESCRIPTION("Texas Instruments LM3646 Dual Flash LED driver");
MODULE_LICENSE("GPL");