lm3646.c

  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * drivers/media/i2c/lm3646.c
  4 * General device driver for TI lm3646, Dual FLASH LED Driver
  5 *
  6 * Copyright (C) 2014 Texas Instruments
  7 *
  8 * Contact: Daniel Jeong <gshark.jeong@gmail.com>
  9 *			Ldd-Mlp <ldd-mlp@list.ti.com>
 10 */
 11
 12#include <linux/delay.h>
 13#include <linux/i2c.h>
 14#include <linux/module.h>
 15#include <linux/slab.h>
 16#include <linux/regmap.h>
 17#include <linux/videodev2.h>
 18#include <media/i2c/lm3646.h>
 19#include <media/v4l2-ctrls.h>
 20#include <media/v4l2-device.h>
 21
 22/* registers definitions */
 23#define REG_ENABLE		0x01
 24#define REG_TORCH_BR	0x05
 25#define REG_FLASH_BR	0x05
 26#define REG_FLASH_TOUT	0x04
 27#define REG_FLAG		0x08
 28#define REG_STROBE_SRC	0x06
 29#define REG_LED1_FLASH_BR 0x06
 30#define REG_LED1_TORCH_BR 0x07
 31
 32#define MASK_ENABLE		0x03
 33#define MASK_TORCH_BR	0x70
 34#define MASK_FLASH_BR	0x0F
 35#define MASK_FLASH_TOUT	0x07
 36#define MASK_FLAG		0xFF
 37#define MASK_STROBE_SRC	0x80
 38
 39/* Fault Mask */
 40#define FAULT_TIMEOUT	(1<<0)
 41#define FAULT_SHORT_CIRCUIT	(1<<1)
 42#define FAULT_UVLO		(1<<2)
 43#define FAULT_IVFM		(1<<3)
 44#define FAULT_OCP		(1<<4)
 45#define FAULT_OVERTEMP	(1<<5)
 46#define FAULT_NTC_TRIP	(1<<6)
 47#define FAULT_OVP		(1<<7)
 48
 49enum led_mode {
 50	MODE_SHDN = 0x0,
 51	MODE_TORCH = 0x2,
 52	MODE_FLASH = 0x3,
 53};
 54
 55/*
 56 * struct lm3646_flash
 57 *
 58 * @pdata: platform data
 59 * @regmap: reg. map for i2c
 60 * @lock: muxtex for serial access.
 61 * @led_mode: V4L2 LED mode
 62 * @ctrls_led: V4L2 controls
 63 * @subdev_led: V4L2 subdev
 64 * @mode_reg : mode register value
 65 */
 66struct lm3646_flash {
 67	struct device *dev;
 68	struct lm3646_platform_data *pdata;
 69	struct regmap *regmap;
 70
 71	struct v4l2_ctrl_handler ctrls_led;
 72	struct v4l2_subdev subdev_led;
 73
 74	u8 mode_reg;
 75};
 76
 77#define to_lm3646_flash(_ctrl)	\
 78	container_of(_ctrl->handler, struct lm3646_flash, ctrls_led)
 79
 80/* enable mode control */
 81static int lm3646_mode_ctrl(struct lm3646_flash *flash,
 82			    enum v4l2_flash_led_mode led_mode)
 83{
 84	switch (led_mode) {
 85	case V4L2_FLASH_LED_MODE_NONE:
 86		return regmap_write(flash->regmap,
 87				    REG_ENABLE, flash->mode_reg | MODE_SHDN);
 88	case V4L2_FLASH_LED_MODE_TORCH:
 89		return regmap_write(flash->regmap,
 90				    REG_ENABLE, flash->mode_reg | MODE_TORCH);
 91	case V4L2_FLASH_LED_MODE_FLASH:
 92		return regmap_write(flash->regmap,
 93				    REG_ENABLE, flash->mode_reg | MODE_FLASH);
 94	}
 95	return -EINVAL;
 96}
 97
 98/* V4L2 controls  */
 99static int lm3646_get_ctrl(struct v4l2_ctrl *ctrl)
100{
101	struct lm3646_flash *flash = to_lm3646_flash(ctrl);
102	unsigned int reg_val;
103	int rval;
104
105	if (ctrl->id != V4L2_CID_FLASH_FAULT)
106		return -EINVAL;
107
108	rval = regmap_read(flash->regmap, REG_FLAG, &reg_val);
109	if (rval < 0)
110		return rval;
111
112	ctrl->val = 0;
113	if (reg_val & FAULT_TIMEOUT)
114		ctrl->val |= V4L2_FLASH_FAULT_TIMEOUT;
115	if (reg_val & FAULT_SHORT_CIRCUIT)
116		ctrl->val |= V4L2_FLASH_FAULT_SHORT_CIRCUIT;
117	if (reg_val & FAULT_UVLO)
118		ctrl->val |= V4L2_FLASH_FAULT_UNDER_VOLTAGE;
119	if (reg_val & FAULT_IVFM)
120		ctrl->val |= V4L2_FLASH_FAULT_INPUT_VOLTAGE;
121	if (reg_val & FAULT_OCP)
122		ctrl->val |= V4L2_FLASH_FAULT_OVER_CURRENT;
123	if (reg_val & FAULT_OVERTEMP)
124		ctrl->val |= V4L2_FLASH_FAULT_OVER_TEMPERATURE;
125	if (reg_val & FAULT_NTC_TRIP)
126		ctrl->val |= V4L2_FLASH_FAULT_LED_OVER_TEMPERATURE;
127	if (reg_val & FAULT_OVP)
128		ctrl->val |= V4L2_FLASH_FAULT_OVER_VOLTAGE;
129
130	return 0;
131}
132
133static int lm3646_set_ctrl(struct v4l2_ctrl *ctrl)
134{
135	struct lm3646_flash *flash = to_lm3646_flash(ctrl);
136	unsigned int reg_val;
137	int rval;
138
139	switch (ctrl->id) {
140	case V4L2_CID_FLASH_LED_MODE:
141
142		if (ctrl->val != V4L2_FLASH_LED_MODE_FLASH)
143			return lm3646_mode_ctrl(flash, ctrl->val);
144		/* switch to SHDN mode before flash strobe on */
145		return lm3646_mode_ctrl(flash, V4L2_FLASH_LED_MODE_NONE);
146
147	case V4L2_CID_FLASH_STROBE_SOURCE:
148		return regmap_update_bits(flash->regmap,
149					  REG_STROBE_SRC, MASK_STROBE_SRC,
150					  (ctrl->val) << 7);
151
152	case V4L2_CID_FLASH_STROBE:
153
154		/* read and check current mode of chip to start flash */
155		rval = regmap_read(flash->regmap, REG_ENABLE, &reg_val);
156		if (rval < 0 || ((reg_val & MASK_ENABLE) != MODE_SHDN))
157			return rval;
158		/* flash on */
159		return lm3646_mode_ctrl(flash, V4L2_FLASH_LED_MODE_FLASH);
160
161	case V4L2_CID_FLASH_STROBE_STOP:
162
163		/*
164		 * flash mode will be turned automatically
165		 * from FLASH mode to SHDN mode after flash duration timeout
166		 * read and check current mode of chip to stop flash
167		 */
168		rval = regmap_read(flash->regmap, REG_ENABLE, &reg_val);
169		if (rval < 0)
170			return rval;
171		if ((reg_val & MASK_ENABLE) == MODE_FLASH)
172			return lm3646_mode_ctrl(flash,
173						V4L2_FLASH_LED_MODE_NONE);
174		return rval;
175
176	case V4L2_CID_FLASH_TIMEOUT:
177		return regmap_update_bits(flash->regmap,
178					  REG_FLASH_TOUT, MASK_FLASH_TOUT,
179					  LM3646_FLASH_TOUT_ms_TO_REG
180					  (ctrl->val));
181
182	case V4L2_CID_FLASH_INTENSITY:
183		return regmap_update_bits(flash->regmap,
184					  REG_FLASH_BR, MASK_FLASH_BR,
185					  LM3646_TOTAL_FLASH_BRT_uA_TO_REG
186					  (ctrl->val));
187
188	case V4L2_CID_FLASH_TORCH_INTENSITY:
189		return regmap_update_bits(flash->regmap,
190					  REG_TORCH_BR, MASK_TORCH_BR,
191					  LM3646_TOTAL_TORCH_BRT_uA_TO_REG
192					  (ctrl->val) << 4);
193	}
194
195	return -EINVAL;
196}
197
198static const struct v4l2_ctrl_ops lm3646_led_ctrl_ops = {
199	.g_volatile_ctrl = lm3646_get_ctrl,
200	.s_ctrl = lm3646_set_ctrl,
201};
202
203static int lm3646_init_controls(struct lm3646_flash *flash)
204{
205	struct v4l2_ctrl *fault;
206	struct v4l2_ctrl_handler *hdl = &flash->ctrls_led;
207	const struct v4l2_ctrl_ops *ops = &lm3646_led_ctrl_ops;
208
209	v4l2_ctrl_handler_init(hdl, 8);
210	/* flash mode */
211	v4l2_ctrl_new_std_menu(hdl, ops, V4L2_CID_FLASH_LED_MODE,
212			       V4L2_FLASH_LED_MODE_TORCH, ~0x7,
213			       V4L2_FLASH_LED_MODE_NONE);
214
215	/* flash source */
216	v4l2_ctrl_new_std_menu(hdl, ops, V4L2_CID_FLASH_STROBE_SOURCE,
217			       0x1, ~0x3, V4L2_FLASH_STROBE_SOURCE_SOFTWARE);
218
219	/* flash strobe */
220	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_STROBE, 0, 0, 0, 0);
221	/* flash strobe stop */
222	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_STROBE_STOP, 0, 0, 0, 0);
223
224	/* flash strobe timeout */
225	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_TIMEOUT,
226			  LM3646_FLASH_TOUT_MIN,
227			  LM3646_FLASH_TOUT_MAX,
228			  LM3646_FLASH_TOUT_STEP, flash->pdata->flash_timeout);
229
230	/* max flash current */
231	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_INTENSITY,
232			  LM3646_TOTAL_FLASH_BRT_MIN,
233			  LM3646_TOTAL_FLASH_BRT_MAX,
234			  LM3646_TOTAL_FLASH_BRT_STEP,
235			  LM3646_TOTAL_FLASH_BRT_MAX);
236
237	/* max torch current */
238	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_TORCH_INTENSITY,
239			  LM3646_TOTAL_TORCH_BRT_MIN,
240			  LM3646_TOTAL_TORCH_BRT_MAX,
241			  LM3646_TOTAL_TORCH_BRT_STEP,
242			  LM3646_TOTAL_TORCH_BRT_MAX);
243
244	/* fault */
245	fault = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FLASH_FAULT, 0,
246				  V4L2_FLASH_FAULT_OVER_VOLTAGE
247				  | V4L2_FLASH_FAULT_OVER_TEMPERATURE
248				  | V4L2_FLASH_FAULT_SHORT_CIRCUIT
249				  | V4L2_FLASH_FAULT_TIMEOUT, 0, 0);
250	if (fault != NULL)
251		fault->flags |= V4L2_CTRL_FLAG_VOLATILE;
252
253	if (hdl->error)
254		return hdl->error;
255
256	flash->subdev_led.ctrl_handler = hdl;
257	return 0;
258}
259
260/* initialize device */
261static const struct v4l2_subdev_ops lm3646_ops = {
262	.core = NULL,
263};
264
265static const struct regmap_config lm3646_regmap = {
266	.reg_bits = 8,
267	.val_bits = 8,
268	.max_register = 0xFF,
269};
270
271static int lm3646_subdev_init(struct lm3646_flash *flash)
272{
273	struct i2c_client *client = to_i2c_client(flash->dev);
274	int rval;
275
276	v4l2_i2c_subdev_init(&flash->subdev_led, client, &lm3646_ops);
277	flash->subdev_led.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
278	strscpy(flash->subdev_led.name, LM3646_NAME,
279		sizeof(flash->subdev_led.name));
280	rval = lm3646_init_controls(flash);
281	if (rval)
282		goto err_out;
283	rval = media_entity_pads_init(&flash->subdev_led.entity, 0, NULL);
284	if (rval < 0)
285		goto err_out;
286	flash->subdev_led.entity.function = MEDIA_ENT_F_FLASH;
287	return rval;
288
289err_out:
290	v4l2_ctrl_handler_free(&flash->ctrls_led);
291	return rval;
292}
293
294static int lm3646_init_device(struct lm3646_flash *flash)
295{
296	unsigned int reg_val;
297	int rval;
298
299	/* read the value of mode register to reduce redundant i2c accesses */
300	rval = regmap_read(flash->regmap, REG_ENABLE, &reg_val);
301	if (rval < 0)
302		return rval;
303	flash->mode_reg = reg_val & 0xfc;
304
305	/* output disable */
306	rval = lm3646_mode_ctrl(flash, V4L2_FLASH_LED_MODE_NONE);
307	if (rval < 0)
308		return rval;
309
310	/*
311	 * LED1 flash current setting
312	 * LED2 flash current = Total(Max) flash current - LED1 flash current
313	 */
314	rval = regmap_update_bits(flash->regmap,
315				  REG_LED1_FLASH_BR, 0x7F,
316				  LM3646_LED1_FLASH_BRT_uA_TO_REG
317				  (flash->pdata->led1_flash_brt));
318
319	if (rval < 0)
320		return rval;
321
322	/*
323	 * LED1 torch current setting
324	 * LED2 torch current = Total(Max) torch current - LED1 torch current
325	 */
326	rval = regmap_update_bits(flash->regmap,
327				  REG_LED1_TORCH_BR, 0x7F,
328				  LM3646_LED1_TORCH_BRT_uA_TO_REG
329				  (flash->pdata->led1_torch_brt));
330	if (rval < 0)
331		return rval;
332
333	/* Reset flag register */
334	return regmap_read(flash->regmap, REG_FLAG, &reg_val);
335}
336
337static int lm3646_probe(struct i2c_client *client)
338{
339	struct lm3646_flash *flash;
340	struct lm3646_platform_data *pdata = dev_get_platdata(&client->dev);
341	int rval;
342
343	flash = devm_kzalloc(&client->dev, sizeof(*flash), GFP_KERNEL);
344	if (flash == NULL)
345		return -ENOMEM;
346
347	flash->regmap = devm_regmap_init_i2c(client, &lm3646_regmap);
348	if (IS_ERR(flash->regmap))
349		return PTR_ERR(flash->regmap);
350
351	/* check device tree if there is no platform data */
352	if (pdata == NULL) {
353		pdata = devm_kzalloc(&client->dev,
354				     sizeof(struct lm3646_platform_data),
355				     GFP_KERNEL);
356		if (pdata == NULL)
357			return -ENOMEM;
358		/* use default data in case of no platform data */
359		pdata->flash_timeout = LM3646_FLASH_TOUT_MAX;
360		pdata->led1_torch_brt = LM3646_LED1_TORCH_BRT_MAX;
361		pdata->led1_flash_brt = LM3646_LED1_FLASH_BRT_MAX;
362	}
363	flash->pdata = pdata;
364	flash->dev = &client->dev;
365
366	rval = lm3646_subdev_init(flash);
367	if (rval < 0)
368		return rval;
369
370	rval = lm3646_init_device(flash);
371	if (rval < 0)
372		return rval;
373
374	i2c_set_clientdata(client, flash);
375
376	return 0;
377}
378
379static void lm3646_remove(struct i2c_client *client)
380{
381	struct lm3646_flash *flash = i2c_get_clientdata(client);
382
383	v4l2_device_unregister_subdev(&flash->subdev_led);
384	v4l2_ctrl_handler_free(&flash->ctrls_led);
385	media_entity_cleanup(&flash->subdev_led.entity);
386}
387
388static const struct i2c_device_id lm3646_id_table[] = {
389	{ LM3646_NAME },
390	{}
391};
392
393MODULE_DEVICE_TABLE(i2c, lm3646_id_table);
394
395static struct i2c_driver lm3646_i2c_driver = {
396	.driver = {
397		   .name = LM3646_NAME,
398		   },
399	.probe = lm3646_probe,
400	.remove = lm3646_remove,
401	.id_table = lm3646_id_table,
402};
403
404module_i2c_driver(lm3646_i2c_driver);
405
406MODULE_AUTHOR("Daniel Jeong <gshark.jeong@gmail.com>");
407MODULE_AUTHOR("Ldd Mlp <ldd-mlp@list.ti.com>");
408MODULE_DESCRIPTION("Texas Instruments LM3646 Dual Flash LED driver");
409MODULE_LICENSE("GPL");