xref: /openbmc/linux/drivers/media/i2c/adp1653.c (revision 9cfc5c90)
1 /*
2  * drivers/media/i2c/adp1653.c
3  *
4  * Copyright (C) 2008--2011 Nokia Corporation
5  *
6  * Contact: Sakari Ailus <sakari.ailus@iki.fi>
7  *
8  * Contributors:
9  *	Sakari Ailus <sakari.ailus@iki.fi>
10  *	Tuukka Toivonen <tuukkat76@gmail.com>
11  *	Pavel Machek <pavel@ucw.cz>
12  *
13  * This program is free software; you can redistribute it and/or
14  * modify it under the terms of the GNU General Public License
15  * version 2 as published by the Free Software Foundation.
16  *
17  * This program is distributed in the hope that it will be useful, but
18  * WITHOUT ANY WARRANTY; without even the implied warranty of
19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
20  * General Public License for more details.
21  *
22  * You should have received a copy of the GNU General Public License
23  * along with this program; if not, write to the Free Software
24  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
25  * 02110-1301 USA
26  *
27  * TODO:
28  * - fault interrupt handling
29  * - hardware strobe
30  * - power doesn't need to be ON if all lights are off
31  *
32  */
33 
34 #include <linux/delay.h>
35 #include <linux/module.h>
36 #include <linux/i2c.h>
37 #include <linux/slab.h>
38 #include <linux/of.h>
39 #include <linux/gpio/consumer.h>
40 #include <media/adp1653.h>
41 #include <media/v4l2-device.h>
42 
43 #define TIMEOUT_MAX		820000
44 #define TIMEOUT_STEP		54600
45 #define TIMEOUT_MIN		(TIMEOUT_MAX - ADP1653_REG_CONFIG_TMR_SET_MAX \
46 				 * TIMEOUT_STEP)
47 #define TIMEOUT_US_TO_CODE(t)	((TIMEOUT_MAX + (TIMEOUT_STEP / 2) - (t)) \
48 				 / TIMEOUT_STEP)
49 #define TIMEOUT_CODE_TO_US(c)	(TIMEOUT_MAX - (c) * TIMEOUT_STEP)
50 
51 /* Write values into ADP1653 registers. */
52 static int adp1653_update_hw(struct adp1653_flash *flash)
53 {
54 	struct i2c_client *client = v4l2_get_subdevdata(&flash->subdev);
55 	u8 out_sel;
56 	u8 config = 0;
57 	int rval;
58 
59 	out_sel = ADP1653_INDICATOR_INTENSITY_uA_TO_REG(
60 		flash->indicator_intensity->val)
61 		<< ADP1653_REG_OUT_SEL_ILED_SHIFT;
62 
63 	switch (flash->led_mode->val) {
64 	case V4L2_FLASH_LED_MODE_NONE:
65 		break;
66 	case V4L2_FLASH_LED_MODE_FLASH:
67 		/* Flash mode, light on with strobe, duration from timer */
68 		config = ADP1653_REG_CONFIG_TMR_CFG;
69 		config |= TIMEOUT_US_TO_CODE(flash->flash_timeout->val)
70 			  << ADP1653_REG_CONFIG_TMR_SET_SHIFT;
71 		break;
72 	case V4L2_FLASH_LED_MODE_TORCH:
73 		/* Torch mode, light immediately on, duration indefinite */
74 		out_sel |= ADP1653_FLASH_INTENSITY_mA_TO_REG(
75 			flash->torch_intensity->val)
76 			<< ADP1653_REG_OUT_SEL_HPLED_SHIFT;
77 		break;
78 	}
79 
80 	rval = i2c_smbus_write_byte_data(client, ADP1653_REG_OUT_SEL, out_sel);
81 	if (rval < 0)
82 		return rval;
83 
84 	rval = i2c_smbus_write_byte_data(client, ADP1653_REG_CONFIG, config);
85 	if (rval < 0)
86 		return rval;
87 
88 	return 0;
89 }
90 
91 static int adp1653_get_fault(struct adp1653_flash *flash)
92 {
93 	struct i2c_client *client = v4l2_get_subdevdata(&flash->subdev);
94 	int fault;
95 	int rval;
96 
97 	fault = i2c_smbus_read_byte_data(client, ADP1653_REG_FAULT);
98 	if (IS_ERR_VALUE(fault))
99 		return fault;
100 
101 	flash->fault |= fault;
102 
103 	if (!flash->fault)
104 		return 0;
105 
106 	/* Clear faults. */
107 	rval = i2c_smbus_write_byte_data(client, ADP1653_REG_OUT_SEL, 0);
108 	if (IS_ERR_VALUE(rval))
109 		return rval;
110 
111 	flash->led_mode->val = V4L2_FLASH_LED_MODE_NONE;
112 
113 	rval = adp1653_update_hw(flash);
114 	if (IS_ERR_VALUE(rval))
115 		return rval;
116 
117 	return flash->fault;
118 }
119 
120 static int adp1653_strobe(struct adp1653_flash *flash, int enable)
121 {
122 	struct i2c_client *client = v4l2_get_subdevdata(&flash->subdev);
123 	u8 out_sel = ADP1653_INDICATOR_INTENSITY_uA_TO_REG(
124 		flash->indicator_intensity->val)
125 		<< ADP1653_REG_OUT_SEL_ILED_SHIFT;
126 	int rval;
127 
128 	if (flash->led_mode->val != V4L2_FLASH_LED_MODE_FLASH)
129 		return -EBUSY;
130 
131 	if (!enable)
132 		return i2c_smbus_write_byte_data(client, ADP1653_REG_OUT_SEL,
133 						 out_sel);
134 
135 	out_sel |= ADP1653_FLASH_INTENSITY_mA_TO_REG(
136 		flash->flash_intensity->val)
137 		<< ADP1653_REG_OUT_SEL_HPLED_SHIFT;
138 	rval = i2c_smbus_write_byte_data(client, ADP1653_REG_OUT_SEL, out_sel);
139 	if (rval)
140 		return rval;
141 
142 	/* Software strobe using i2c */
143 	rval = i2c_smbus_write_byte_data(client, ADP1653_REG_SW_STROBE,
144 		ADP1653_REG_SW_STROBE_SW_STROBE);
145 	if (rval)
146 		return rval;
147 	return i2c_smbus_write_byte_data(client, ADP1653_REG_SW_STROBE, 0);
148 }
149 
150 /* --------------------------------------------------------------------------
151  * V4L2 controls
152  */
153 
154 static int adp1653_get_ctrl(struct v4l2_ctrl *ctrl)
155 {
156 	struct adp1653_flash *flash =
157 		container_of(ctrl->handler, struct adp1653_flash, ctrls);
158 	int rval;
159 
160 	rval = adp1653_get_fault(flash);
161 	if (IS_ERR_VALUE(rval))
162 		return rval;
163 
164 	ctrl->cur.val = 0;
165 
166 	if (flash->fault & ADP1653_REG_FAULT_FLT_SCP)
167 		ctrl->cur.val |= V4L2_FLASH_FAULT_SHORT_CIRCUIT;
168 	if (flash->fault & ADP1653_REG_FAULT_FLT_OT)
169 		ctrl->cur.val |= V4L2_FLASH_FAULT_OVER_TEMPERATURE;
170 	if (flash->fault & ADP1653_REG_FAULT_FLT_TMR)
171 		ctrl->cur.val |= V4L2_FLASH_FAULT_TIMEOUT;
172 	if (flash->fault & ADP1653_REG_FAULT_FLT_OV)
173 		ctrl->cur.val |= V4L2_FLASH_FAULT_OVER_VOLTAGE;
174 
175 	flash->fault = 0;
176 
177 	return 0;
178 }
179 
180 static int adp1653_set_ctrl(struct v4l2_ctrl *ctrl)
181 {
182 	struct adp1653_flash *flash =
183 		container_of(ctrl->handler, struct adp1653_flash, ctrls);
184 	int rval;
185 
186 	rval = adp1653_get_fault(flash);
187 	if (IS_ERR_VALUE(rval))
188 		return rval;
189 	if ((rval & (ADP1653_REG_FAULT_FLT_SCP |
190 		     ADP1653_REG_FAULT_FLT_OT |
191 		     ADP1653_REG_FAULT_FLT_OV)) &&
192 	    (ctrl->id == V4L2_CID_FLASH_STROBE ||
193 	     ctrl->id == V4L2_CID_FLASH_TORCH_INTENSITY ||
194 	     ctrl->id == V4L2_CID_FLASH_LED_MODE))
195 		return -EBUSY;
196 
197 	switch (ctrl->id) {
198 	case V4L2_CID_FLASH_STROBE:
199 		return adp1653_strobe(flash, 1);
200 	case V4L2_CID_FLASH_STROBE_STOP:
201 		return adp1653_strobe(flash, 0);
202 	}
203 
204 	return adp1653_update_hw(flash);
205 }
206 
207 static const struct v4l2_ctrl_ops adp1653_ctrl_ops = {
208 	.g_volatile_ctrl = adp1653_get_ctrl,
209 	.s_ctrl = adp1653_set_ctrl,
210 };
211 
212 static int adp1653_init_controls(struct adp1653_flash *flash)
213 {
214 	struct v4l2_ctrl *fault;
215 
216 	v4l2_ctrl_handler_init(&flash->ctrls, 9);
217 
218 	flash->led_mode =
219 		v4l2_ctrl_new_std_menu(&flash->ctrls, &adp1653_ctrl_ops,
220 				       V4L2_CID_FLASH_LED_MODE,
221 				       V4L2_FLASH_LED_MODE_TORCH, ~0x7, 0);
222 	v4l2_ctrl_new_std_menu(&flash->ctrls, &adp1653_ctrl_ops,
223 			       V4L2_CID_FLASH_STROBE_SOURCE,
224 			       V4L2_FLASH_STROBE_SOURCE_SOFTWARE, ~0x1, 0);
225 	v4l2_ctrl_new_std(&flash->ctrls, &adp1653_ctrl_ops,
226 			  V4L2_CID_FLASH_STROBE, 0, 0, 0, 0);
227 	v4l2_ctrl_new_std(&flash->ctrls, &adp1653_ctrl_ops,
228 			  V4L2_CID_FLASH_STROBE_STOP, 0, 0, 0, 0);
229 	flash->flash_timeout =
230 		v4l2_ctrl_new_std(&flash->ctrls, &adp1653_ctrl_ops,
231 				  V4L2_CID_FLASH_TIMEOUT, TIMEOUT_MIN,
232 				  flash->platform_data->max_flash_timeout,
233 				  TIMEOUT_STEP,
234 				  flash->platform_data->max_flash_timeout);
235 	flash->flash_intensity =
236 		v4l2_ctrl_new_std(&flash->ctrls, &adp1653_ctrl_ops,
237 				  V4L2_CID_FLASH_INTENSITY,
238 				  ADP1653_FLASH_INTENSITY_MIN,
239 				  flash->platform_data->max_flash_intensity,
240 				  1, flash->platform_data->max_flash_intensity);
241 	flash->torch_intensity =
242 		v4l2_ctrl_new_std(&flash->ctrls, &adp1653_ctrl_ops,
243 				  V4L2_CID_FLASH_TORCH_INTENSITY,
244 				  ADP1653_TORCH_INTENSITY_MIN,
245 				  flash->platform_data->max_torch_intensity,
246 				  ADP1653_FLASH_INTENSITY_STEP,
247 				  flash->platform_data->max_torch_intensity);
248 	flash->indicator_intensity =
249 		v4l2_ctrl_new_std(&flash->ctrls, &adp1653_ctrl_ops,
250 				  V4L2_CID_FLASH_INDICATOR_INTENSITY,
251 				  ADP1653_INDICATOR_INTENSITY_MIN,
252 				  flash->platform_data->max_indicator_intensity,
253 				  ADP1653_INDICATOR_INTENSITY_STEP,
254 				  ADP1653_INDICATOR_INTENSITY_MIN);
255 	fault = v4l2_ctrl_new_std(&flash->ctrls, &adp1653_ctrl_ops,
256 				  V4L2_CID_FLASH_FAULT, 0,
257 				  V4L2_FLASH_FAULT_OVER_VOLTAGE
258 				  | V4L2_FLASH_FAULT_OVER_TEMPERATURE
259 				  | V4L2_FLASH_FAULT_SHORT_CIRCUIT, 0, 0);
260 
261 	if (flash->ctrls.error)
262 		return flash->ctrls.error;
263 
264 	fault->flags |= V4L2_CTRL_FLAG_VOLATILE;
265 
266 	flash->subdev.ctrl_handler = &flash->ctrls;
267 	return 0;
268 }
269 
270 /* --------------------------------------------------------------------------
271  * V4L2 subdev operations
272  */
273 
274 static int
275 adp1653_init_device(struct adp1653_flash *flash)
276 {
277 	struct i2c_client *client = v4l2_get_subdevdata(&flash->subdev);
278 	int rval;
279 
280 	/* Clear FAULT register by writing zero to OUT_SEL */
281 	rval = i2c_smbus_write_byte_data(client, ADP1653_REG_OUT_SEL, 0);
282 	if (rval < 0) {
283 		dev_err(&client->dev, "failed writing fault register\n");
284 		return -EIO;
285 	}
286 
287 	mutex_lock(flash->ctrls.lock);
288 	/* Reset faults before reading new ones. */
289 	flash->fault = 0;
290 	rval = adp1653_get_fault(flash);
291 	mutex_unlock(flash->ctrls.lock);
292 	if (rval > 0) {
293 		dev_err(&client->dev, "faults detected: 0x%1.1x\n", rval);
294 		return -EIO;
295 	}
296 
297 	mutex_lock(flash->ctrls.lock);
298 	rval = adp1653_update_hw(flash);
299 	mutex_unlock(flash->ctrls.lock);
300 	if (rval) {
301 		dev_err(&client->dev,
302 			"adp1653_update_hw failed at %s\n", __func__);
303 		return -EIO;
304 	}
305 
306 	return 0;
307 }
308 
309 static int
310 __adp1653_set_power(struct adp1653_flash *flash, int on)
311 {
312 	int ret;
313 
314 	if (flash->platform_data->power) {
315 		ret = flash->platform_data->power(&flash->subdev, on);
316 		if (ret < 0)
317 			return ret;
318 	} else {
319 		gpiod_set_value(flash->platform_data->enable_gpio, on);
320 		if (on)
321 			/* Some delay is apparently required. */
322 			udelay(20);
323 	}
324 
325 	if (!on)
326 		return 0;
327 
328 	ret = adp1653_init_device(flash);
329 	if (ret >= 0)
330 		return ret;
331 
332 	if (flash->platform_data->power)
333 		flash->platform_data->power(&flash->subdev, 0);
334 	else
335 		gpiod_set_value(flash->platform_data->enable_gpio, 0);
336 
337 	return ret;
338 }
339 
340 static int
341 adp1653_set_power(struct v4l2_subdev *subdev, int on)
342 {
343 	struct adp1653_flash *flash = to_adp1653_flash(subdev);
344 	int ret = 0;
345 
346 	mutex_lock(&flash->power_lock);
347 
348 	/* If the power count is modified from 0 to != 0 or from != 0 to 0,
349 	 * update the power state.
350 	 */
351 	if (flash->power_count == !on) {
352 		ret = __adp1653_set_power(flash, !!on);
353 		if (ret < 0)
354 			goto done;
355 	}
356 
357 	/* Update the power count. */
358 	flash->power_count += on ? 1 : -1;
359 	WARN_ON(flash->power_count < 0);
360 
361 done:
362 	mutex_unlock(&flash->power_lock);
363 	return ret;
364 }
365 
366 static int adp1653_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
367 {
368 	return adp1653_set_power(sd, 1);
369 }
370 
371 static int adp1653_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
372 {
373 	return adp1653_set_power(sd, 0);
374 }
375 
376 static const struct v4l2_subdev_core_ops adp1653_core_ops = {
377 	.s_power = adp1653_set_power,
378 };
379 
380 static const struct v4l2_subdev_ops adp1653_ops = {
381 	.core = &adp1653_core_ops,
382 };
383 
384 static const struct v4l2_subdev_internal_ops adp1653_internal_ops = {
385 	.open = adp1653_open,
386 	.close = adp1653_close,
387 };
388 
389 /* --------------------------------------------------------------------------
390  * I2C driver
391  */
392 #ifdef CONFIG_PM
393 
394 static int adp1653_suspend(struct device *dev)
395 {
396 	struct i2c_client *client = to_i2c_client(dev);
397 	struct v4l2_subdev *subdev = i2c_get_clientdata(client);
398 	struct adp1653_flash *flash = to_adp1653_flash(subdev);
399 
400 	if (!flash->power_count)
401 		return 0;
402 
403 	return __adp1653_set_power(flash, 0);
404 }
405 
406 static int adp1653_resume(struct device *dev)
407 {
408 	struct i2c_client *client = to_i2c_client(dev);
409 	struct v4l2_subdev *subdev = i2c_get_clientdata(client);
410 	struct adp1653_flash *flash = to_adp1653_flash(subdev);
411 
412 	if (!flash->power_count)
413 		return 0;
414 
415 	return __adp1653_set_power(flash, 1);
416 }
417 
418 #else
419 
420 #define adp1653_suspend	NULL
421 #define adp1653_resume	NULL
422 
423 #endif /* CONFIG_PM */
424 
425 static int adp1653_of_init(struct i2c_client *client,
426 			   struct adp1653_flash *flash,
427 			   struct device_node *node)
428 {
429 	struct adp1653_platform_data *pd;
430 	struct device_node *child;
431 
432 	pd = devm_kzalloc(&client->dev, sizeof(*pd), GFP_KERNEL);
433 	if (!pd)
434 		return -ENOMEM;
435 	flash->platform_data = pd;
436 
437 	child = of_get_child_by_name(node, "flash");
438 	if (!child)
439 		return -EINVAL;
440 
441 	if (of_property_read_u32(child, "flash-timeout-us",
442 				 &pd->max_flash_timeout))
443 		goto err;
444 
445 	if (of_property_read_u32(child, "flash-max-microamp",
446 				 &pd->max_flash_intensity))
447 		goto err;
448 
449 	pd->max_flash_intensity /= 1000;
450 
451 	if (of_property_read_u32(child, "led-max-microamp",
452 				 &pd->max_torch_intensity))
453 		goto err;
454 
455 	pd->max_torch_intensity /= 1000;
456 	of_node_put(child);
457 
458 	child = of_get_child_by_name(node, "indicator");
459 	if (!child)
460 		return -EINVAL;
461 
462 	if (of_property_read_u32(child, "led-max-microamp",
463 				 &pd->max_indicator_intensity))
464 		goto err;
465 
466 	of_node_put(child);
467 
468 	pd->enable_gpio = devm_gpiod_get(&client->dev, "enable", GPIOD_OUT_LOW);
469 	if (!pd->enable_gpio) {
470 		dev_err(&client->dev, "Error getting GPIO\n");
471 		return -EINVAL;
472 	}
473 
474 	return 0;
475 err:
476 	dev_err(&client->dev, "Required property not found\n");
477 	of_node_put(child);
478 	return -EINVAL;
479 }
480 
481 
482 static int adp1653_probe(struct i2c_client *client,
483 			 const struct i2c_device_id *devid)
484 {
485 	struct adp1653_flash *flash;
486 	int ret;
487 
488 	flash = devm_kzalloc(&client->dev, sizeof(*flash), GFP_KERNEL);
489 	if (flash == NULL)
490 		return -ENOMEM;
491 
492 	if (client->dev.of_node) {
493 		ret = adp1653_of_init(client, flash, client->dev.of_node);
494 		if (ret)
495 			return ret;
496 	} else {
497 		if (!client->dev.platform_data) {
498 			dev_err(&client->dev,
499 				"Neither DT not platform data provided\n");
500 			return EINVAL;
501 		}
502 		flash->platform_data = client->dev.platform_data;
503 	}
504 
505 	mutex_init(&flash->power_lock);
506 
507 	v4l2_i2c_subdev_init(&flash->subdev, client, &adp1653_ops);
508 	flash->subdev.internal_ops = &adp1653_internal_ops;
509 	flash->subdev.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
510 
511 	ret = adp1653_init_controls(flash);
512 	if (ret)
513 		goto free_and_quit;
514 
515 	ret = media_entity_init(&flash->subdev.entity, 0, NULL, 0);
516 	if (ret < 0)
517 		goto free_and_quit;
518 
519 	flash->subdev.entity.type = MEDIA_ENT_T_V4L2_SUBDEV_FLASH;
520 
521 	return 0;
522 
523 free_and_quit:
524 	dev_err(&client->dev, "adp1653: failed to register device\n");
525 	v4l2_ctrl_handler_free(&flash->ctrls);
526 	return ret;
527 }
528 
529 static int adp1653_remove(struct i2c_client *client)
530 {
531 	struct v4l2_subdev *subdev = i2c_get_clientdata(client);
532 	struct adp1653_flash *flash = to_adp1653_flash(subdev);
533 
534 	v4l2_device_unregister_subdev(&flash->subdev);
535 	v4l2_ctrl_handler_free(&flash->ctrls);
536 	media_entity_cleanup(&flash->subdev.entity);
537 
538 	return 0;
539 }
540 
541 static const struct i2c_device_id adp1653_id_table[] = {
542 	{ ADP1653_NAME, 0 },
543 	{ }
544 };
545 MODULE_DEVICE_TABLE(i2c, adp1653_id_table);
546 
547 static const struct dev_pm_ops adp1653_pm_ops = {
548 	.suspend	= adp1653_suspend,
549 	.resume		= adp1653_resume,
550 };
551 
552 static struct i2c_driver adp1653_i2c_driver = {
553 	.driver		= {
554 		.name	= ADP1653_NAME,
555 		.pm	= &adp1653_pm_ops,
556 	},
557 	.probe		= adp1653_probe,
558 	.remove		= adp1653_remove,
559 	.id_table	= adp1653_id_table,
560 };
561 
562 module_i2c_driver(adp1653_i2c_driver);
563 
564 MODULE_AUTHOR("Sakari Ailus <sakari.ailus@nokia.com>");
565 MODULE_DESCRIPTION("Analog Devices ADP1653 LED flash driver");
566 MODULE_LICENSE("GPL");
567