1/*
2 * drivers/media/i2c/lm3646.c
3 * General device driver for TI lm3646, Dual FLASH LED Driver
4 *
5 * Copyright (C) 2014 Texas Instruments
6 *
7 * Contact: Daniel Jeong <gshark.jeong@gmail.com>
8 *			Ldd-Mlp <ldd-mlp@list.ti.com>
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License
12 * version 2 as published by the Free Software Foundation.
13 */
14
15#include <linux/delay.h>
16#include <linux/i2c.h>
17#include <linux/module.h>
18#include <linux/slab.h>
19#include <linux/regmap.h>
20#include <linux/videodev2.h>
21#include <media/lm3646.h>
22#include <media/v4l2-ctrls.h>
23#include <media/v4l2-device.h>
24
25/* registers definitions */
26#define REG_ENABLE		0x01
27#define REG_TORCH_BR	0x05
28#define REG_FLASH_BR	0x05
29#define REG_FLASH_TOUT	0x04
30#define REG_FLAG		0x08
31#define REG_STROBE_SRC	0x06
32#define REG_LED1_FLASH_BR 0x06
33#define REG_LED1_TORCH_BR 0x07
34
35#define MASK_ENABLE		0x03
36#define MASK_TORCH_BR	0x70
37#define MASK_FLASH_BR	0x0F
38#define MASK_FLASH_TOUT	0x07
39#define MASK_FLAG		0xFF
40#define MASK_STROBE_SRC	0x80
41
42/* Fault Mask */
43#define FAULT_TIMEOUT	(1<<0)
44#define FAULT_SHORT_CIRCUIT	(1<<1)
45#define FAULT_UVLO		(1<<2)
46#define FAULT_IVFM		(1<<3)
47#define FAULT_OCP		(1<<4)
48#define FAULT_OVERTEMP	(1<<5)
49#define FAULT_NTC_TRIP	(1<<6)
50#define FAULT_OVP		(1<<7)
51
52enum led_mode {
53	MODE_SHDN = 0x0,
54	MODE_TORCH = 0x2,
55	MODE_FLASH = 0x3,
56};
57
58/*
59 * struct lm3646_flash
60 *
61 * @pdata: platform data
62 * @regmap: reg. map for i2c
63 * @lock: muxtex for serial access.
64 * @led_mode: V4L2 LED mode
65 * @ctrls_led: V4L2 contols
66 * @subdev_led: V4L2 subdev
67 * @mode_reg : mode register value
68 */
69struct lm3646_flash {
70	struct device *dev;
71	struct lm3646_platform_data *pdata;
72	struct regmap *regmap;
73
74	struct v4l2_ctrl_handler ctrls_led;
75	struct v4l2_subdev subdev_led;
76
77	u8 mode_reg;
78};
79
80#define to_lm3646_flash(_ctrl)	\
81	container_of(_ctrl->handler, struct lm3646_flash, ctrls_led)
82
83/* enable mode control */
84static int lm3646_mode_ctrl(struct lm3646_flash *flash,
85			    enum v4l2_flash_led_mode led_mode)
86{
87	switch (led_mode) {
88	case V4L2_FLASH_LED_MODE_NONE:
89		return regmap_write(flash->regmap,
90				    REG_ENABLE, flash->mode_reg | MODE_SHDN);
91	case V4L2_FLASH_LED_MODE_TORCH:
92		return regmap_write(flash->regmap,
93				    REG_ENABLE, flash->mode_reg | MODE_TORCH);
94	case V4L2_FLASH_LED_MODE_FLASH:
95		return regmap_write(flash->regmap,
96				    REG_ENABLE, flash->mode_reg | MODE_FLASH);
97	}
98	return -EINVAL;
99}
100
101/* V4L2 controls  */
102static int lm3646_get_ctrl(struct v4l2_ctrl *ctrl)
103{
104	struct lm3646_flash *flash = to_lm3646_flash(ctrl);
105	unsigned int reg_val;
106	int rval;
107
108	if (ctrl->id != V4L2_CID_FLASH_FAULT)
109		return -EINVAL;
110
111	rval = regmap_read(flash->regmap, REG_FLAG, &reg_val);
112	if (rval < 0)
113		return rval;
114
115	ctrl->val = 0;
116	if (reg_val & FAULT_TIMEOUT)
117		ctrl->val |= V4L2_FLASH_FAULT_TIMEOUT;
118	if (reg_val & FAULT_SHORT_CIRCUIT)
119		ctrl->val |= V4L2_FLASH_FAULT_SHORT_CIRCUIT;
120	if (reg_val & FAULT_UVLO)
121		ctrl->val |= V4L2_FLASH_FAULT_UNDER_VOLTAGE;
122	if (reg_val & FAULT_IVFM)
123		ctrl->val |= V4L2_FLASH_FAULT_INPUT_VOLTAGE;
124	if (reg_val & FAULT_OCP)
125		ctrl->val |= V4L2_FLASH_FAULT_OVER_CURRENT;
126	if (reg_val & FAULT_OVERTEMP)
127		ctrl->val |= V4L2_FLASH_FAULT_OVER_TEMPERATURE;
128	if (reg_val & FAULT_NTC_TRIP)
129		ctrl->val |= V4L2_FLASH_FAULT_LED_OVER_TEMPERATURE;
130	if (reg_val & FAULT_OVP)
131		ctrl->val |= V4L2_FLASH_FAULT_OVER_VOLTAGE;
132
133	return 0;
134}
135
136static int lm3646_set_ctrl(struct v4l2_ctrl *ctrl)
137{
138	struct lm3646_flash *flash = to_lm3646_flash(ctrl);
139	unsigned int reg_val;
140	int rval = -EINVAL;
141
142	switch (ctrl->id) {
143	case V4L2_CID_FLASH_LED_MODE:
144
145		if (ctrl->val != V4L2_FLASH_LED_MODE_FLASH)
146			return lm3646_mode_ctrl(flash, ctrl->val);
147		/* switch to SHDN mode before flash strobe on */
148		return lm3646_mode_ctrl(flash, V4L2_FLASH_LED_MODE_NONE);
149
150	case V4L2_CID_FLASH_STROBE_SOURCE:
151		return regmap_update_bits(flash->regmap,
152					  REG_STROBE_SRC, MASK_STROBE_SRC,
153					  (ctrl->val) << 7);
154
155	case V4L2_CID_FLASH_STROBE:
156
157		/* read and check current mode of chip to start flash */
158		rval = regmap_read(flash->regmap, REG_ENABLE, &reg_val);
159		if (rval < 0 || ((reg_val & MASK_ENABLE) != MODE_SHDN))
160			return rval;
161		/* flash on */
162		return lm3646_mode_ctrl(flash, V4L2_FLASH_LED_MODE_FLASH);
163
164	case V4L2_CID_FLASH_STROBE_STOP:
165
166		/*
167		 * flash mode will be turned automatically
168		 * from FLASH mode to SHDN mode after flash duration timeout
169		 * read and check current mode of chip to stop flash
170		 */
171		rval = regmap_read(flash->regmap, REG_ENABLE, &reg_val);
172		if (rval < 0)
173			return rval;
174		if ((reg_val & MASK_ENABLE) == MODE_FLASH)
175			return lm3646_mode_ctrl(flash,
176						V4L2_FLASH_LED_MODE_NONE);
177		return rval;
178
179	case V4L2_CID_FLASH_TIMEOUT:
180		return regmap_update_bits(flash->regmap,
181					  REG_FLASH_TOUT, MASK_FLASH_TOUT,
182					  LM3646_FLASH_TOUT_ms_TO_REG
183					  (ctrl->val));
184
185	case V4L2_CID_FLASH_INTENSITY:
186		return regmap_update_bits(flash->regmap,
187					  REG_FLASH_BR, MASK_FLASH_BR,
188					  LM3646_TOTAL_FLASH_BRT_uA_TO_REG
189					  (ctrl->val));
190
191	case V4L2_CID_FLASH_TORCH_INTENSITY:
192		return regmap_update_bits(flash->regmap,
193					  REG_TORCH_BR, MASK_TORCH_BR,
194					  LM3646_TOTAL_TORCH_BRT_uA_TO_REG
195					  (ctrl->val) << 4);
196	}
197
198	return -EINVAL;
199}
200
201static const struct v4l2_ctrl_ops lm3646_led_ctrl_ops = {
202	.g_volatile_ctrl = lm3646_get_ctrl,
203	.s_ctrl = lm3646_set_ctrl,
204};
205
206static int lm3646_init_controls(struct lm3646_flash *flash)
207{
208	struct v4l2_ctrl *fault;
209	struct v4l2_ctrl_handler *hdl = &flash->ctrls_led;
210	const struct v4l2_ctrl_ops *ops = &lm3646_led_ctrl_ops;
211
212	v4l2_ctrl_handler_init(hdl, 8);
213	/* flash mode */
214	v4l2_ctrl_new_std_menu(hdl, ops, V4L2_CID_FLASH_LED_MODE,
215			       V4L2_FLASH_LED_MODE_TORCH, ~0x7,
216			       V4L2_FLASH_LED_MODE_NONE);
217
218	/* flash source */
219	v4l2_ctrl_new_std_menu(hdl, ops, V4L2_CID_FLASH_STROBE_SOURCE,
220			       0x1, ~0x3, V4L2_FLASH_STROBE_SOURCE_SOFTWARE);
221
222	/* flash strobe */
223	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_STROBE, 0, 0, 0, 0);
224	/* flash strobe stop */
225	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_STROBE_STOP, 0, 0, 0, 0);
226
227	/* flash strobe timeout */
228	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_TIMEOUT,
229			  LM3646_FLASH_TOUT_MIN,
230			  LM3646_FLASH_TOUT_MAX,
231			  LM3646_FLASH_TOUT_STEP, flash->pdata->flash_timeout);
232
233	/* max flash current */
234	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_INTENSITY,
235			  LM3646_TOTAL_FLASH_BRT_MIN,
236			  LM3646_TOTAL_FLASH_BRT_MAX,
237			  LM3646_TOTAL_FLASH_BRT_STEP,
238			  LM3646_TOTAL_FLASH_BRT_MAX);
239
240	/* max torch current */
241	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_TORCH_INTENSITY,
242			  LM3646_TOTAL_TORCH_BRT_MIN,
243			  LM3646_TOTAL_TORCH_BRT_MAX,
244			  LM3646_TOTAL_TORCH_BRT_STEP,
245			  LM3646_TOTAL_TORCH_BRT_MAX);
246
247	/* fault */
248	fault = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_FAULT, 0,
249				  V4L2_FLASH_FAULT_OVER_VOLTAGE
250				  | V4L2_FLASH_FAULT_OVER_TEMPERATURE
251				  | V4L2_FLASH_FAULT_SHORT_CIRCUIT
252				  | V4L2_FLASH_FAULT_TIMEOUT, 0, 0);
253	if (fault != NULL)
254		fault->flags |= V4L2_CTRL_FLAG_VOLATILE;
255
256	if (hdl->error)
257		return hdl->error;
258
259	flash->subdev_led.ctrl_handler = hdl;
260	return 0;
261}
262
263/* initialize device */
264static const struct v4l2_subdev_ops lm3646_ops = {
265	.core = NULL,
266};
267
268static const struct regmap_config lm3646_regmap = {
269	.reg_bits = 8,
270	.val_bits = 8,
271	.max_register = 0xFF,
272};
273
274static int lm3646_subdev_init(struct lm3646_flash *flash)
275{
276	struct i2c_client *client = to_i2c_client(flash->dev);
277	int rval;
278
279	v4l2_i2c_subdev_init(&flash->subdev_led, client, &lm3646_ops);
280	flash->subdev_led.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
281	strcpy(flash->subdev_led.name, LM3646_NAME);
282	rval = lm3646_init_controls(flash);
283	if (rval)
284		goto err_out;
285	rval = media_entity_init(&flash->subdev_led.entity, 0, NULL, 0);
286	if (rval < 0)
287		goto err_out;
288	flash->subdev_led.entity.type = MEDIA_ENT_T_V4L2_SUBDEV_FLASH;
289	return rval;
290
291err_out:
292	v4l2_ctrl_handler_free(&flash->ctrls_led);
293	return rval;
294}
295
296static int lm3646_init_device(struct lm3646_flash *flash)
297{
298	unsigned int reg_val;
299	int rval;
300
301	/* read the value of mode register to reduce redundant i2c accesses */
302	rval = regmap_read(flash->regmap, REG_ENABLE, &reg_val);
303	if (rval < 0)
304		return rval;
305	flash->mode_reg = reg_val & 0xfc;
306
307	/* output disable */
308	rval = lm3646_mode_ctrl(flash, V4L2_FLASH_LED_MODE_NONE);
309	if (rval < 0)
310		return rval;
311
312	/*
313	 * LED1 flash current setting
314	 * LED2 flash current = Total(Max) flash current - LED1 flash current
315	 */
316	rval = regmap_update_bits(flash->regmap,
317				  REG_LED1_FLASH_BR, 0x7F,
318				  LM3646_LED1_FLASH_BRT_uA_TO_REG
319				  (flash->pdata->led1_flash_brt));
320
321	if (rval < 0)
322		return rval;
323
324	/*
325	 * LED1 torch current setting
326	 * LED2 torch current = Total(Max) torch current - LED1 torch current
327	 */
328	rval = regmap_update_bits(flash->regmap,
329				  REG_LED1_TORCH_BR, 0x7F,
330				  LM3646_LED1_TORCH_BRT_uA_TO_REG
331				  (flash->pdata->led1_torch_brt));
332	if (rval < 0)
333		return rval;
334
335	/* Reset flag register */
336	return regmap_read(flash->regmap, REG_FLAG, &reg_val);
337}
338
339static int lm3646_probe(struct i2c_client *client,
340			const struct i2c_device_id *devid)
341{
342	struct lm3646_flash *flash;
343	struct lm3646_platform_data *pdata = dev_get_platdata(&client->dev);
344	int rval;
345
346	flash = devm_kzalloc(&client->dev, sizeof(*flash), GFP_KERNEL);
347	if (flash == NULL)
348		return -ENOMEM;
349
350	flash->regmap = devm_regmap_init_i2c(client, &lm3646_regmap);
351	if (IS_ERR(flash->regmap))
352		return PTR_ERR(flash->regmap);
353
354	/* check device tree if there is no platform data */
355	if (pdata == NULL) {
356		pdata = devm_kzalloc(&client->dev,
357				     sizeof(struct lm3646_platform_data),
358				     GFP_KERNEL);
359		if (pdata == NULL)
360			return -ENOMEM;
361		/* use default data in case of no platform data */
362		pdata->flash_timeout = LM3646_FLASH_TOUT_MAX;
363		pdata->led1_torch_brt = LM3646_LED1_TORCH_BRT_MAX;
364		pdata->led1_flash_brt = LM3646_LED1_FLASH_BRT_MAX;
365	}
366	flash->pdata = pdata;
367	flash->dev = &client->dev;
368
369	rval = lm3646_subdev_init(flash);
370	if (rval < 0)
371		return rval;
372
373	rval = lm3646_init_device(flash);
374	if (rval < 0)
375		return rval;
376
377	i2c_set_clientdata(client, flash);
378
379	return 0;
380}
381
382static int lm3646_remove(struct i2c_client *client)
383{
384	struct lm3646_flash *flash = i2c_get_clientdata(client);
385
386	v4l2_device_unregister_subdev(&flash->subdev_led);
387	v4l2_ctrl_handler_free(&flash->ctrls_led);
388	media_entity_cleanup(&flash->subdev_led.entity);
389
390	return 0;
391}
392
393static const struct i2c_device_id lm3646_id_table[] = {
394	{LM3646_NAME, 0},
395	{}
396};
397
398MODULE_DEVICE_TABLE(i2c, lm3646_id_table);
399
400static struct i2c_driver lm3646_i2c_driver = {
401	.driver = {
402		   .name = LM3646_NAME,
403		   },
404	.probe = lm3646_probe,
405	.remove = lm3646_remove,
406	.id_table = lm3646_id_table,
407};
408
409module_i2c_driver(lm3646_i2c_driver);
410
411MODULE_AUTHOR("Daniel Jeong <gshark.jeong@gmail.com>");
412MODULE_AUTHOR("Ldd Mlp <ldd-mlp@list.ti.com>");
413MODULE_DESCRIPTION("Texas Instruments LM3646 Dual Flash LED driver");
414MODULE_LICENSE("GPL");
415