xref: /openbmc/linux/drivers/media/i2c/dw9768.c (revision f68f2ff9)
1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (c) 2020 MediaTek Inc.
3 
4 #include <linux/delay.h>
5 #include <linux/i2c.h>
6 #include <linux/module.h>
7 #include <linux/pm_runtime.h>
8 #include <linux/regulator/consumer.h>
9 #include <media/v4l2-async.h>
10 #include <media/v4l2-ctrls.h>
11 #include <media/v4l2-device.h>
12 #include <media/v4l2-fwnode.h>
13 #include <media/v4l2-subdev.h>
14 
15 #define DW9768_NAME				"dw9768"
16 #define DW9768_MAX_FOCUS_POS			(1024 - 1)
17 /*
18  * This sets the minimum granularity for the focus positions.
19  * A value of 1 gives maximum accuracy for a desired focus position
20  */
21 #define DW9768_FOCUS_STEPS			1
22 
23 /*
24  * Ring control and Power control register
25  * Bit[1] RING_EN
26  * 0: Direct mode
27  * 1: AAC mode (ringing control mode)
28  * Bit[0] PD
29  * 0: Normal operation mode
30  * 1: Power down mode
31  * DW9768 requires waiting time of Topr after PD reset takes place.
32  */
33 #define DW9768_RING_PD_CONTROL_REG		0x02
34 #define DW9768_PD_MODE_OFF			0x00
35 #define DW9768_PD_MODE_EN			BIT(0)
36 #define DW9768_AAC_MODE_EN			BIT(1)
37 
38 /*
39  * DW9768 separates two registers to control the VCM position.
40  * One for MSB value, another is LSB value.
41  * DAC_MSB: D[9:8] (ADD: 0x03)
42  * DAC_LSB: D[7:0] (ADD: 0x04)
43  * D[9:0] DAC data input: positive output current = D[9:0] / 1023 * 100[mA]
44  */
45 #define DW9768_MSB_ADDR				0x03
46 #define DW9768_LSB_ADDR				0x04
47 #define DW9768_STATUS_ADDR			0x05
48 
49 /*
50  * AAC mode control & prescale register
51  * Bit[7:5] Namely AC[2:0], decide the VCM mode and operation time.
52  * 001 AAC2 0.48 x Tvib
53  * 010 AAC3 0.70 x Tvib
54  * 011 AAC4 0.75 x Tvib
55  * 101 AAC8 1.13 x Tvib
56  * Bit[2:0] Namely PRESC[2:0], set the internal clock dividing rate as follow.
57  * 000 2
58  * 001 1
59  * 010 1/2
60  * 011 1/4
61  * 100 8
62  * 101 4
63  */
64 #define DW9768_AAC_PRESC_REG			0x06
65 #define DW9768_AAC_MODE_SEL_MASK		GENMASK(7, 5)
66 #define DW9768_CLOCK_PRE_SCALE_SEL_MASK		GENMASK(2, 0)
67 
68 /*
69  * VCM period of vibration register
70  * Bit[5:0] Defined as VCM rising periodic time (Tvib) together with PRESC[2:0]
71  * Tvib = (6.3ms + AACT[5:0] * 0.1ms) * Dividing Rate
72  * Dividing Rate is the internal clock dividing rate that is defined at
73  * PRESCALE register (ADD: 0x06)
74  */
75 #define DW9768_AAC_TIME_REG			0x07
76 
77 /*
78  * DW9768 requires waiting time (delay time) of t_OPR after power-up,
79  * or in the case of PD reset taking place.
80  */
81 #define DW9768_T_OPR_US				1000
82 #define DW9768_TVIB_MS_BASE10			(64 - 1)
83 #define DW9768_AAC_MODE_DEFAULT			2
84 #define DW9768_AAC_TIME_DEFAULT			0x20
85 #define DW9768_CLOCK_PRE_SCALE_DEFAULT		1
86 
87 /*
88  * This acts as the minimum granularity of lens movement.
89  * Keep this value power of 2, so the control steps can be
90  * uniformly adjusted for gradual lens movement, with desired
91  * number of control steps.
92  */
93 #define DW9768_MOVE_STEPS			16
94 
95 static const char * const dw9768_supply_names[] = {
96 	"vin",	/* Digital I/O power */
97 	"vdd",	/* Digital core power */
98 };
99 
100 /* dw9768 device structure */
101 struct dw9768 {
102 	struct regulator_bulk_data supplies[ARRAY_SIZE(dw9768_supply_names)];
103 	struct v4l2_ctrl_handler ctrls;
104 	struct v4l2_ctrl *focus;
105 	struct v4l2_subdev sd;
106 
107 	u32 aac_mode;
108 	u32 aac_timing;
109 	u32 clock_presc;
110 	u32 move_delay_us;
111 };
112 
113 static inline struct dw9768 *sd_to_dw9768(struct v4l2_subdev *subdev)
114 {
115 	return container_of(subdev, struct dw9768, sd);
116 }
117 
118 struct regval_list {
119 	u8 reg_num;
120 	u8 value;
121 };
122 
123 struct dw9768_aac_mode_ot_multi {
124 	u32 aac_mode_enum;
125 	u32 ot_multi_base100;
126 };
127 
128 struct dw9768_clk_presc_dividing_rate {
129 	u32 clk_presc_enum;
130 	u32 dividing_rate_base100;
131 };
132 
133 static const struct dw9768_aac_mode_ot_multi aac_mode_ot_multi[] = {
134 	{1,  48},
135 	{2,  70},
136 	{3,  75},
137 	{5, 113},
138 };
139 
140 static const struct dw9768_clk_presc_dividing_rate presc_dividing_rate[] = {
141 	{0, 200},
142 	{1, 100},
143 	{2,  50},
144 	{3,  25},
145 	{4, 800},
146 	{5, 400},
147 };
148 
149 static u32 dw9768_find_ot_multi(u32 aac_mode_param)
150 {
151 	u32 cur_ot_multi_base100 = 70;
152 	unsigned int i;
153 
154 	for (i = 0; i < ARRAY_SIZE(aac_mode_ot_multi); i++) {
155 		if (aac_mode_ot_multi[i].aac_mode_enum == aac_mode_param) {
156 			cur_ot_multi_base100 =
157 				aac_mode_ot_multi[i].ot_multi_base100;
158 		}
159 	}
160 
161 	return cur_ot_multi_base100;
162 }
163 
164 static u32 dw9768_find_dividing_rate(u32 presc_param)
165 {
166 	u32 cur_clk_dividing_rate_base100 = 100;
167 	unsigned int i;
168 
169 	for (i = 0; i < ARRAY_SIZE(presc_dividing_rate); i++) {
170 		if (presc_dividing_rate[i].clk_presc_enum == presc_param) {
171 			cur_clk_dividing_rate_base100 =
172 				presc_dividing_rate[i].dividing_rate_base100;
173 		}
174 	}
175 
176 	return cur_clk_dividing_rate_base100;
177 }
178 
179 /*
180  * DW9768_AAC_PRESC_REG & DW9768_AAC_TIME_REG determine VCM operation time.
181  * For current VCM mode: AAC3, Operation Time would be 0.70 x Tvib.
182  * Tvib = (6.3ms + AACT[5:0] * 0.1MS) * Dividing Rate.
183  * Below is calculation of the operation delay for each step.
184  */
185 static inline u32 dw9768_cal_move_delay(u32 aac_mode_param, u32 presc_param,
186 					u32 aac_timing_param)
187 {
188 	u32 Tvib_us;
189 	u32 ot_multi_base100;
190 	u32 clk_dividing_rate_base100;
191 
192 	ot_multi_base100 = dw9768_find_ot_multi(aac_mode_param);
193 
194 	clk_dividing_rate_base100 = dw9768_find_dividing_rate(presc_param);
195 
196 	Tvib_us = (DW9768_TVIB_MS_BASE10 + aac_timing_param) *
197 		  clk_dividing_rate_base100;
198 
199 	return Tvib_us * ot_multi_base100 / 100;
200 }
201 
202 static int dw9768_mod_reg(struct dw9768 *dw9768, u8 reg, u8 mask, u8 val)
203 {
204 	struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
205 	int ret;
206 
207 	ret = i2c_smbus_read_byte_data(client, reg);
208 	if (ret < 0)
209 		return ret;
210 
211 	val = ((unsigned char)ret & ~mask) | (val & mask);
212 
213 	return i2c_smbus_write_byte_data(client, reg, val);
214 }
215 
216 static int dw9768_set_dac(struct dw9768 *dw9768, u16 val)
217 {
218 	struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
219 
220 	/* Write VCM position to registers */
221 	return i2c_smbus_write_word_swapped(client, DW9768_MSB_ADDR, val);
222 }
223 
224 static int dw9768_init(struct dw9768 *dw9768)
225 {
226 	struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
227 	int ret, val;
228 
229 	/* Reset DW9768_RING_PD_CONTROL_REG to default status 0x00 */
230 	ret = i2c_smbus_write_byte_data(client, DW9768_RING_PD_CONTROL_REG,
231 					DW9768_PD_MODE_OFF);
232 	if (ret < 0)
233 		return ret;
234 
235 	/*
236 	 * DW9769 requires waiting delay time of t_OPR
237 	 * after PD reset takes place.
238 	 */
239 	usleep_range(DW9768_T_OPR_US, DW9768_T_OPR_US + 100);
240 
241 	/* Set DW9768_RING_PD_CONTROL_REG to DW9768_AAC_MODE_EN(0x01) */
242 	ret = i2c_smbus_write_byte_data(client, DW9768_RING_PD_CONTROL_REG,
243 					DW9768_AAC_MODE_EN);
244 	if (ret < 0)
245 		return ret;
246 
247 	/* Set AAC mode */
248 	ret = dw9768_mod_reg(dw9768, DW9768_AAC_PRESC_REG,
249 			     DW9768_AAC_MODE_SEL_MASK,
250 			     dw9768->aac_mode << 5);
251 	if (ret < 0)
252 		return ret;
253 
254 	/* Set clock presc */
255 	if (dw9768->clock_presc != DW9768_CLOCK_PRE_SCALE_DEFAULT) {
256 		ret = dw9768_mod_reg(dw9768, DW9768_AAC_PRESC_REG,
257 				     DW9768_CLOCK_PRE_SCALE_SEL_MASK,
258 				     dw9768->clock_presc);
259 		if (ret < 0)
260 			return ret;
261 	}
262 
263 	/* Set AAC Timing */
264 	if (dw9768->aac_timing != DW9768_AAC_TIME_DEFAULT) {
265 		ret = i2c_smbus_write_byte_data(client, DW9768_AAC_TIME_REG,
266 						dw9768->aac_timing);
267 		if (ret < 0)
268 			return ret;
269 	}
270 
271 	for (val = dw9768->focus->val % DW9768_MOVE_STEPS;
272 	     val <= dw9768->focus->val;
273 	     val += DW9768_MOVE_STEPS) {
274 		ret = dw9768_set_dac(dw9768, val);
275 		if (ret) {
276 			dev_err(&client->dev, "I2C failure: %d", ret);
277 			return ret;
278 		}
279 		usleep_range(dw9768->move_delay_us,
280 			     dw9768->move_delay_us + 1000);
281 	}
282 
283 	return 0;
284 }
285 
286 static int dw9768_release(struct dw9768 *dw9768)
287 {
288 	struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
289 	int ret, val;
290 
291 	val = round_down(dw9768->focus->val, DW9768_MOVE_STEPS);
292 	for ( ; val >= 0; val -= DW9768_MOVE_STEPS) {
293 		ret = dw9768_set_dac(dw9768, val);
294 		if (ret) {
295 			dev_err(&client->dev, "I2C write fail: %d", ret);
296 			return ret;
297 		}
298 		usleep_range(dw9768->move_delay_us,
299 			     dw9768->move_delay_us + 1000);
300 	}
301 
302 	ret = i2c_smbus_write_byte_data(client, DW9768_RING_PD_CONTROL_REG,
303 					DW9768_PD_MODE_EN);
304 	if (ret < 0)
305 		return ret;
306 
307 	/*
308 	 * DW9769 requires waiting delay time of t_OPR
309 	 * after PD reset takes place.
310 	 */
311 	usleep_range(DW9768_T_OPR_US, DW9768_T_OPR_US + 100);
312 
313 	return 0;
314 }
315 
316 static int dw9768_runtime_suspend(struct device *dev)
317 {
318 	struct v4l2_subdev *sd = dev_get_drvdata(dev);
319 	struct dw9768 *dw9768 = sd_to_dw9768(sd);
320 
321 	dw9768_release(dw9768);
322 	regulator_bulk_disable(ARRAY_SIZE(dw9768_supply_names),
323 			       dw9768->supplies);
324 
325 	return 0;
326 }
327 
328 static int dw9768_runtime_resume(struct device *dev)
329 {
330 	struct v4l2_subdev *sd = dev_get_drvdata(dev);
331 	struct dw9768 *dw9768 = sd_to_dw9768(sd);
332 	int ret;
333 
334 	ret = regulator_bulk_enable(ARRAY_SIZE(dw9768_supply_names),
335 				    dw9768->supplies);
336 	if (ret < 0) {
337 		dev_err(dev, "failed to enable regulators\n");
338 		return ret;
339 	}
340 
341 	/*
342 	 * The datasheet refers to t_OPR that needs to be waited before sending
343 	 * I2C commands after power-up.
344 	 */
345 	usleep_range(DW9768_T_OPR_US, DW9768_T_OPR_US + 100);
346 
347 	ret = dw9768_init(dw9768);
348 	if (ret < 0)
349 		goto disable_regulator;
350 
351 	return 0;
352 
353 disable_regulator:
354 	regulator_bulk_disable(ARRAY_SIZE(dw9768_supply_names),
355 			       dw9768->supplies);
356 
357 	return ret;
358 }
359 
360 static int dw9768_set_ctrl(struct v4l2_ctrl *ctrl)
361 {
362 	struct dw9768 *dw9768 = container_of(ctrl->handler,
363 					     struct dw9768, ctrls);
364 
365 	if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE)
366 		return dw9768_set_dac(dw9768, ctrl->val);
367 
368 	return 0;
369 }
370 
371 static const struct v4l2_ctrl_ops dw9768_ctrl_ops = {
372 	.s_ctrl = dw9768_set_ctrl,
373 };
374 
375 static int dw9768_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
376 {
377 	return pm_runtime_resume_and_get(sd->dev);
378 }
379 
380 static int dw9768_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
381 {
382 	pm_runtime_put(sd->dev);
383 
384 	return 0;
385 }
386 
387 static const struct v4l2_subdev_internal_ops dw9768_int_ops = {
388 	.open = dw9768_open,
389 	.close = dw9768_close,
390 };
391 
392 static const struct v4l2_subdev_ops dw9768_ops = { };
393 
394 static int dw9768_init_controls(struct dw9768 *dw9768)
395 {
396 	struct v4l2_ctrl_handler *hdl = &dw9768->ctrls;
397 	const struct v4l2_ctrl_ops *ops = &dw9768_ctrl_ops;
398 
399 	v4l2_ctrl_handler_init(hdl, 1);
400 
401 	dw9768->focus = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE, 0,
402 					  DW9768_MAX_FOCUS_POS,
403 					  DW9768_FOCUS_STEPS, 0);
404 
405 	if (hdl->error)
406 		return hdl->error;
407 
408 	dw9768->sd.ctrl_handler = hdl;
409 
410 	return 0;
411 }
412 
413 static int dw9768_probe(struct i2c_client *client)
414 {
415 	struct device *dev = &client->dev;
416 	struct dw9768 *dw9768;
417 	unsigned int i;
418 	int ret;
419 
420 	dw9768 = devm_kzalloc(dev, sizeof(*dw9768), GFP_KERNEL);
421 	if (!dw9768)
422 		return -ENOMEM;
423 
424 	/* Initialize subdev */
425 	v4l2_i2c_subdev_init(&dw9768->sd, client, &dw9768_ops);
426 
427 	dw9768->aac_mode = DW9768_AAC_MODE_DEFAULT;
428 	dw9768->aac_timing = DW9768_AAC_TIME_DEFAULT;
429 	dw9768->clock_presc = DW9768_CLOCK_PRE_SCALE_DEFAULT;
430 
431 	/* Optional indication of AAC mode select */
432 	fwnode_property_read_u32(dev_fwnode(dev), "dongwoon,aac-mode",
433 				 &dw9768->aac_mode);
434 
435 	/* Optional indication of clock pre-scale select */
436 	fwnode_property_read_u32(dev_fwnode(dev), "dongwoon,clock-presc",
437 				 &dw9768->clock_presc);
438 
439 	/* Optional indication of AAC Timing */
440 	fwnode_property_read_u32(dev_fwnode(dev), "dongwoon,aac-timing",
441 				 &dw9768->aac_timing);
442 
443 	dw9768->move_delay_us = dw9768_cal_move_delay(dw9768->aac_mode,
444 						      dw9768->clock_presc,
445 						      dw9768->aac_timing);
446 
447 	for (i = 0; i < ARRAY_SIZE(dw9768_supply_names); i++)
448 		dw9768->supplies[i].supply = dw9768_supply_names[i];
449 
450 	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(dw9768_supply_names),
451 				      dw9768->supplies);
452 	if (ret) {
453 		dev_err(dev, "failed to get regulators\n");
454 		return ret;
455 	}
456 
457 	/* Initialize controls */
458 	ret = dw9768_init_controls(dw9768);
459 	if (ret)
460 		goto err_free_handler;
461 
462 	/* Initialize subdev */
463 	dw9768->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
464 	dw9768->sd.internal_ops = &dw9768_int_ops;
465 
466 	ret = media_entity_pads_init(&dw9768->sd.entity, 0, NULL);
467 	if (ret < 0)
468 		goto err_free_handler;
469 
470 	dw9768->sd.entity.function = MEDIA_ENT_F_LENS;
471 
472 	/*
473 	 * Device is already turned on by i2c-core with ACPI domain PM.
474 	 * Attempt to turn off the device to satisfy the privacy LED concerns.
475 	 */
476 	pm_runtime_set_active(dev);
477 	pm_runtime_enable(dev);
478 	if (!pm_runtime_enabled(dev)) {
479 		ret = dw9768_runtime_resume(dev);
480 		if (ret < 0) {
481 			dev_err(dev, "failed to power on: %d\n", ret);
482 			goto err_clean_entity;
483 		}
484 	}
485 
486 	ret = v4l2_async_register_subdev(&dw9768->sd);
487 	if (ret < 0) {
488 		dev_err(dev, "failed to register V4L2 subdev: %d", ret);
489 		goto err_power_off;
490 	}
491 	pm_runtime_idle(dev);
492 
493 	return 0;
494 
495 err_power_off:
496 	if (pm_runtime_enabled(dev))
497 		pm_runtime_disable(dev);
498 	else
499 		dw9768_runtime_suspend(dev);
500 err_clean_entity:
501 	media_entity_cleanup(&dw9768->sd.entity);
502 err_free_handler:
503 	v4l2_ctrl_handler_free(&dw9768->ctrls);
504 
505 	return ret;
506 }
507 
508 static int dw9768_remove(struct i2c_client *client)
509 {
510 	struct v4l2_subdev *sd = i2c_get_clientdata(client);
511 	struct dw9768 *dw9768 = sd_to_dw9768(sd);
512 
513 	v4l2_async_unregister_subdev(&dw9768->sd);
514 	v4l2_ctrl_handler_free(&dw9768->ctrls);
515 	media_entity_cleanup(&dw9768->sd.entity);
516 	pm_runtime_disable(&client->dev);
517 	if (!pm_runtime_status_suspended(&client->dev))
518 		dw9768_runtime_suspend(&client->dev);
519 	pm_runtime_set_suspended(&client->dev);
520 
521 	return 0;
522 }
523 
524 static const struct of_device_id dw9768_of_table[] = {
525 	{ .compatible = "dongwoon,dw9768" },
526 	{ .compatible = "giantec,gt9769" },
527 	{}
528 };
529 MODULE_DEVICE_TABLE(of, dw9768_of_table);
530 
531 static const struct dev_pm_ops dw9768_pm_ops = {
532 	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
533 				pm_runtime_force_resume)
534 	SET_RUNTIME_PM_OPS(dw9768_runtime_suspend, dw9768_runtime_resume, NULL)
535 };
536 
537 static struct i2c_driver dw9768_i2c_driver = {
538 	.driver = {
539 		.name = DW9768_NAME,
540 		.pm = &dw9768_pm_ops,
541 		.of_match_table = dw9768_of_table,
542 	},
543 	.probe_new  = dw9768_probe,
544 	.remove = dw9768_remove,
545 };
546 module_i2c_driver(dw9768_i2c_driver);
547 
548 MODULE_AUTHOR("Dongchun Zhu <dongchun.zhu@mediatek.com>");
549 MODULE_DESCRIPTION("DW9768 VCM driver");
550 MODULE_LICENSE("GPL v2");
551