xref: /linux/drivers/media/i2c/dw9768.c (revision 55d0969c451159cff86949b38c39171cab962069)
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 dw9768_aac_mode_ot_multi {
119 	u32 aac_mode_enum;
120 	u32 ot_multi_base100;
121 };
122 
123 struct dw9768_clk_presc_dividing_rate {
124 	u32 clk_presc_enum;
125 	u32 dividing_rate_base100;
126 };
127 
128 static const struct dw9768_aac_mode_ot_multi aac_mode_ot_multi[] = {
129 	{1,  48},
130 	{2,  70},
131 	{3,  75},
132 	{5, 113},
133 };
134 
135 static const struct dw9768_clk_presc_dividing_rate presc_dividing_rate[] = {
136 	{0, 200},
137 	{1, 100},
138 	{2,  50},
139 	{3,  25},
140 	{4, 800},
141 	{5, 400},
142 };
143 
144 static u32 dw9768_find_ot_multi(u32 aac_mode_param)
145 {
146 	u32 cur_ot_multi_base100 = 70;
147 	unsigned int i;
148 
149 	for (i = 0; i < ARRAY_SIZE(aac_mode_ot_multi); i++) {
150 		if (aac_mode_ot_multi[i].aac_mode_enum == aac_mode_param) {
151 			cur_ot_multi_base100 =
152 				aac_mode_ot_multi[i].ot_multi_base100;
153 		}
154 	}
155 
156 	return cur_ot_multi_base100;
157 }
158 
159 static u32 dw9768_find_dividing_rate(u32 presc_param)
160 {
161 	u32 cur_clk_dividing_rate_base100 = 100;
162 	unsigned int i;
163 
164 	for (i = 0; i < ARRAY_SIZE(presc_dividing_rate); i++) {
165 		if (presc_dividing_rate[i].clk_presc_enum == presc_param) {
166 			cur_clk_dividing_rate_base100 =
167 				presc_dividing_rate[i].dividing_rate_base100;
168 		}
169 	}
170 
171 	return cur_clk_dividing_rate_base100;
172 }
173 
174 /*
175  * DW9768_AAC_PRESC_REG & DW9768_AAC_TIME_REG determine VCM operation time.
176  * For current VCM mode: AAC3, Operation Time would be 0.70 x Tvib.
177  * Tvib = (6.3ms + AACT[5:0] * 0.1MS) * Dividing Rate.
178  * Below is calculation of the operation delay for each step.
179  */
180 static inline u32 dw9768_cal_move_delay(u32 aac_mode_param, u32 presc_param,
181 					u32 aac_timing_param)
182 {
183 	u32 Tvib_us;
184 	u32 ot_multi_base100;
185 	u32 clk_dividing_rate_base100;
186 
187 	ot_multi_base100 = dw9768_find_ot_multi(aac_mode_param);
188 
189 	clk_dividing_rate_base100 = dw9768_find_dividing_rate(presc_param);
190 
191 	Tvib_us = (DW9768_TVIB_MS_BASE10 + aac_timing_param) *
192 		  clk_dividing_rate_base100;
193 
194 	return Tvib_us * ot_multi_base100 / 100;
195 }
196 
197 static int dw9768_mod_reg(struct dw9768 *dw9768, u8 reg, u8 mask, u8 val)
198 {
199 	struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
200 	int ret;
201 
202 	ret = i2c_smbus_read_byte_data(client, reg);
203 	if (ret < 0)
204 		return ret;
205 
206 	val = ((unsigned char)ret & ~mask) | (val & mask);
207 
208 	return i2c_smbus_write_byte_data(client, reg, val);
209 }
210 
211 static int dw9768_set_dac(struct dw9768 *dw9768, u16 val)
212 {
213 	struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
214 
215 	/* Write VCM position to registers */
216 	return i2c_smbus_write_word_swapped(client, DW9768_MSB_ADDR, val);
217 }
218 
219 static int dw9768_init(struct dw9768 *dw9768)
220 {
221 	struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
222 	int ret, val;
223 
224 	/* Reset DW9768_RING_PD_CONTROL_REG to default status 0x00 */
225 	ret = i2c_smbus_write_byte_data(client, DW9768_RING_PD_CONTROL_REG,
226 					DW9768_PD_MODE_OFF);
227 	if (ret < 0)
228 		return ret;
229 
230 	/*
231 	 * DW9769 requires waiting delay time of t_OPR
232 	 * after PD reset takes place.
233 	 */
234 	usleep_range(DW9768_T_OPR_US, DW9768_T_OPR_US + 100);
235 
236 	/* Set DW9768_RING_PD_CONTROL_REG to DW9768_AAC_MODE_EN(0x01) */
237 	ret = i2c_smbus_write_byte_data(client, DW9768_RING_PD_CONTROL_REG,
238 					DW9768_AAC_MODE_EN);
239 	if (ret < 0)
240 		return ret;
241 
242 	/* Set AAC mode */
243 	ret = dw9768_mod_reg(dw9768, DW9768_AAC_PRESC_REG,
244 			     DW9768_AAC_MODE_SEL_MASK,
245 			     dw9768->aac_mode << 5);
246 	if (ret < 0)
247 		return ret;
248 
249 	/* Set clock presc */
250 	if (dw9768->clock_presc != DW9768_CLOCK_PRE_SCALE_DEFAULT) {
251 		ret = dw9768_mod_reg(dw9768, DW9768_AAC_PRESC_REG,
252 				     DW9768_CLOCK_PRE_SCALE_SEL_MASK,
253 				     dw9768->clock_presc);
254 		if (ret < 0)
255 			return ret;
256 	}
257 
258 	/* Set AAC Timing */
259 	if (dw9768->aac_timing != DW9768_AAC_TIME_DEFAULT) {
260 		ret = i2c_smbus_write_byte_data(client, DW9768_AAC_TIME_REG,
261 						dw9768->aac_timing);
262 		if (ret < 0)
263 			return ret;
264 	}
265 
266 	for (val = dw9768->focus->val % DW9768_MOVE_STEPS;
267 	     val <= dw9768->focus->val;
268 	     val += DW9768_MOVE_STEPS) {
269 		ret = dw9768_set_dac(dw9768, val);
270 		if (ret) {
271 			dev_err(&client->dev, "I2C failure: %d", ret);
272 			return ret;
273 		}
274 		usleep_range(dw9768->move_delay_us,
275 			     dw9768->move_delay_us + 1000);
276 	}
277 
278 	return 0;
279 }
280 
281 static int dw9768_release(struct dw9768 *dw9768)
282 {
283 	struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
284 	int ret, val;
285 
286 	val = round_down(dw9768->focus->val, DW9768_MOVE_STEPS);
287 	for ( ; val >= 0; val -= DW9768_MOVE_STEPS) {
288 		ret = dw9768_set_dac(dw9768, val);
289 		if (ret) {
290 			dev_err(&client->dev, "I2C write fail: %d", ret);
291 			return ret;
292 		}
293 		usleep_range(dw9768->move_delay_us,
294 			     dw9768->move_delay_us + 1000);
295 	}
296 
297 	ret = i2c_smbus_write_byte_data(client, DW9768_RING_PD_CONTROL_REG,
298 					DW9768_PD_MODE_EN);
299 	if (ret < 0)
300 		return ret;
301 
302 	/*
303 	 * DW9769 requires waiting delay time of t_OPR
304 	 * after PD reset takes place.
305 	 */
306 	usleep_range(DW9768_T_OPR_US, DW9768_T_OPR_US + 100);
307 
308 	return 0;
309 }
310 
311 static int dw9768_runtime_suspend(struct device *dev)
312 {
313 	struct v4l2_subdev *sd = dev_get_drvdata(dev);
314 	struct dw9768 *dw9768 = sd_to_dw9768(sd);
315 
316 	dw9768_release(dw9768);
317 	regulator_bulk_disable(ARRAY_SIZE(dw9768_supply_names),
318 			       dw9768->supplies);
319 
320 	return 0;
321 }
322 
323 static int dw9768_runtime_resume(struct device *dev)
324 {
325 	struct v4l2_subdev *sd = dev_get_drvdata(dev);
326 	struct dw9768 *dw9768 = sd_to_dw9768(sd);
327 	int ret;
328 
329 	ret = regulator_bulk_enable(ARRAY_SIZE(dw9768_supply_names),
330 				    dw9768->supplies);
331 	if (ret < 0) {
332 		dev_err(dev, "failed to enable regulators\n");
333 		return ret;
334 	}
335 
336 	/*
337 	 * The datasheet refers to t_OPR that needs to be waited before sending
338 	 * I2C commands after power-up.
339 	 */
340 	usleep_range(DW9768_T_OPR_US, DW9768_T_OPR_US + 100);
341 
342 	ret = dw9768_init(dw9768);
343 	if (ret < 0)
344 		goto disable_regulator;
345 
346 	return 0;
347 
348 disable_regulator:
349 	regulator_bulk_disable(ARRAY_SIZE(dw9768_supply_names),
350 			       dw9768->supplies);
351 
352 	return ret;
353 }
354 
355 static int dw9768_set_ctrl(struct v4l2_ctrl *ctrl)
356 {
357 	struct dw9768 *dw9768 = container_of(ctrl->handler,
358 					     struct dw9768, ctrls);
359 
360 	if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE)
361 		return dw9768_set_dac(dw9768, ctrl->val);
362 
363 	return 0;
364 }
365 
366 static const struct v4l2_ctrl_ops dw9768_ctrl_ops = {
367 	.s_ctrl = dw9768_set_ctrl,
368 };
369 
370 static int dw9768_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
371 {
372 	return pm_runtime_resume_and_get(sd->dev);
373 }
374 
375 static int dw9768_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
376 {
377 	pm_runtime_put(sd->dev);
378 
379 	return 0;
380 }
381 
382 static const struct v4l2_subdev_internal_ops dw9768_int_ops = {
383 	.open = dw9768_open,
384 	.close = dw9768_close,
385 };
386 
387 static const struct v4l2_subdev_ops dw9768_ops = { };
388 
389 static int dw9768_init_controls(struct dw9768 *dw9768)
390 {
391 	struct v4l2_ctrl_handler *hdl = &dw9768->ctrls;
392 	const struct v4l2_ctrl_ops *ops = &dw9768_ctrl_ops;
393 
394 	v4l2_ctrl_handler_init(hdl, 1);
395 
396 	dw9768->focus = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE, 0,
397 					  DW9768_MAX_FOCUS_POS,
398 					  DW9768_FOCUS_STEPS, 0);
399 
400 	if (hdl->error)
401 		return hdl->error;
402 
403 	dw9768->sd.ctrl_handler = hdl;
404 
405 	return 0;
406 }
407 
408 static int dw9768_probe(struct i2c_client *client)
409 {
410 	struct device *dev = &client->dev;
411 	struct dw9768 *dw9768;
412 	bool full_power;
413 	unsigned int i;
414 	int ret;
415 
416 	dw9768 = devm_kzalloc(dev, sizeof(*dw9768), GFP_KERNEL);
417 	if (!dw9768)
418 		return -ENOMEM;
419 
420 	/* Initialize subdev */
421 	v4l2_i2c_subdev_init(&dw9768->sd, client, &dw9768_ops);
422 
423 	dw9768->aac_mode = DW9768_AAC_MODE_DEFAULT;
424 	dw9768->aac_timing = DW9768_AAC_TIME_DEFAULT;
425 	dw9768->clock_presc = DW9768_CLOCK_PRE_SCALE_DEFAULT;
426 
427 	/* Optional indication of AAC mode select */
428 	fwnode_property_read_u32(dev_fwnode(dev), "dongwoon,aac-mode",
429 				 &dw9768->aac_mode);
430 
431 	/* Optional indication of clock pre-scale select */
432 	fwnode_property_read_u32(dev_fwnode(dev), "dongwoon,clock-presc",
433 				 &dw9768->clock_presc);
434 
435 	/* Optional indication of AAC Timing */
436 	fwnode_property_read_u32(dev_fwnode(dev), "dongwoon,aac-timing",
437 				 &dw9768->aac_timing);
438 
439 	dw9768->move_delay_us = dw9768_cal_move_delay(dw9768->aac_mode,
440 						      dw9768->clock_presc,
441 						      dw9768->aac_timing);
442 
443 	for (i = 0; i < ARRAY_SIZE(dw9768_supply_names); i++)
444 		dw9768->supplies[i].supply = dw9768_supply_names[i];
445 
446 	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(dw9768_supply_names),
447 				      dw9768->supplies);
448 	if (ret) {
449 		dev_err(dev, "failed to get regulators\n");
450 		return ret;
451 	}
452 
453 	/* Initialize controls */
454 	ret = dw9768_init_controls(dw9768);
455 	if (ret)
456 		goto err_free_handler;
457 
458 	/* Initialize subdev */
459 	dw9768->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
460 	dw9768->sd.internal_ops = &dw9768_int_ops;
461 
462 	ret = media_entity_pads_init(&dw9768->sd.entity, 0, NULL);
463 	if (ret < 0)
464 		goto err_free_handler;
465 
466 	dw9768->sd.entity.function = MEDIA_ENT_F_LENS;
467 
468 	/*
469 	 * Figure out whether we're going to power up the device here. Generally
470 	 * this is done if CONFIG_PM is disabled in a DT system or the device is
471 	 * to be powered on in an ACPI system. Similarly for power off in
472 	 * remove.
473 	 */
474 	pm_runtime_enable(dev);
475 	full_power = (is_acpi_node(dev_fwnode(dev)) &&
476 		      acpi_dev_state_d0(dev)) ||
477 		     (is_of_node(dev_fwnode(dev)) && !pm_runtime_enabled(dev));
478 	if (full_power) {
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 		pm_runtime_set_active(dev);
485 	}
486 
487 	ret = v4l2_async_register_subdev(&dw9768->sd);
488 	if (ret < 0) {
489 		dev_err(dev, "failed to register V4L2 subdev: %d", ret);
490 		goto err_power_off;
491 	}
492 
493 	pm_runtime_idle(dev);
494 
495 	return 0;
496 
497 err_power_off:
498 	if (full_power) {
499 		dw9768_runtime_suspend(dev);
500 		pm_runtime_set_suspended(dev);
501 	}
502 err_clean_entity:
503 	pm_runtime_disable(dev);
504 	media_entity_cleanup(&dw9768->sd.entity);
505 err_free_handler:
506 	v4l2_ctrl_handler_free(&dw9768->ctrls);
507 
508 	return ret;
509 }
510 
511 static void dw9768_remove(struct i2c_client *client)
512 {
513 	struct v4l2_subdev *sd = i2c_get_clientdata(client);
514 	struct dw9768 *dw9768 = sd_to_dw9768(sd);
515 	struct device *dev = &client->dev;
516 
517 	v4l2_async_unregister_subdev(&dw9768->sd);
518 	v4l2_ctrl_handler_free(&dw9768->ctrls);
519 	media_entity_cleanup(&dw9768->sd.entity);
520 	if ((is_acpi_node(dev_fwnode(dev)) && acpi_dev_state_d0(dev)) ||
521 	    (is_of_node(dev_fwnode(dev)) && !pm_runtime_enabled(dev))) {
522 		dw9768_runtime_suspend(dev);
523 		pm_runtime_set_suspended(dev);
524 	}
525 	pm_runtime_disable(dev);
526 }
527 
528 static const struct of_device_id dw9768_of_table[] = {
529 	{ .compatible = "dongwoon,dw9768" },
530 	{ .compatible = "giantec,gt9769" },
531 	{}
532 };
533 MODULE_DEVICE_TABLE(of, dw9768_of_table);
534 
535 static const struct dev_pm_ops dw9768_pm_ops = {
536 	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
537 				pm_runtime_force_resume)
538 	SET_RUNTIME_PM_OPS(dw9768_runtime_suspend, dw9768_runtime_resume, NULL)
539 };
540 
541 static struct i2c_driver dw9768_i2c_driver = {
542 	.driver = {
543 		.name = DW9768_NAME,
544 		.pm = &dw9768_pm_ops,
545 		.of_match_table = dw9768_of_table,
546 	},
547 	.probe = dw9768_probe,
548 	.remove = dw9768_remove,
549 };
550 module_i2c_driver(dw9768_i2c_driver);
551 
552 MODULE_AUTHOR("Dongchun Zhu <dongchun.zhu@mediatek.com>");
553 MODULE_DESCRIPTION("DW9768 VCM driver");
554 MODULE_LICENSE("GPL v2");
555