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
95static const char * const dw9768_supply_names[] = {
96	"vin",	/* Digital I/O power */
97	"vdd",	/* Digital core power */
98};
99
100/* dw9768 device structure */
101struct 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
113static inline struct dw9768 *sd_to_dw9768(struct v4l2_subdev *subdev)
114{
115	return container_of(subdev, struct dw9768, sd);
116}
117
118struct regval_list {
119	u8 reg_num;
120	u8 value;
121};
122
123struct dw9768_aac_mode_ot_multi {
124	u32 aac_mode_enum;
125	u32 ot_multi_base100;
126};
127
128struct dw9768_clk_presc_dividing_rate {
129	u32 clk_presc_enum;
130	u32 dividing_rate_base100;
131};
132
133static 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
140static 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
149static 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
164static 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 */
185static 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
202static 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
216static 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
224static 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
286static 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
316static 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
328static 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
353disable_regulator:
354	regulator_bulk_disable(ARRAY_SIZE(dw9768_supply_names),
355			       dw9768->supplies);
356
357	return ret;
358}
359
360static 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
371static const struct v4l2_ctrl_ops dw9768_ctrl_ops = {
372	.s_ctrl = dw9768_set_ctrl,
373};
374
375static int dw9768_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
376{
377	return pm_runtime_resume_and_get(sd->dev);
378}
379
380static 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
387static const struct v4l2_subdev_internal_ops dw9768_int_ops = {
388	.open = dw9768_open,
389	.close = dw9768_close,
390};
391
392static const struct v4l2_subdev_ops dw9768_ops = { };
393
394static 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
413static int dw9768_probe(struct i2c_client *client)
414{
415	struct device *dev = &client->dev;
416	struct dw9768 *dw9768;
417	bool full_power;
418	unsigned int i;
419	int ret;
420
421	dw9768 = devm_kzalloc(dev, sizeof(*dw9768), GFP_KERNEL);
422	if (!dw9768)
423		return -ENOMEM;
424
425	/* Initialize subdev */
426	v4l2_i2c_subdev_init(&dw9768->sd, client, &dw9768_ops);
427
428	dw9768->aac_mode = DW9768_AAC_MODE_DEFAULT;
429	dw9768->aac_timing = DW9768_AAC_TIME_DEFAULT;
430	dw9768->clock_presc = DW9768_CLOCK_PRE_SCALE_DEFAULT;
431
432	/* Optional indication of AAC mode select */
433	fwnode_property_read_u32(dev_fwnode(dev), "dongwoon,aac-mode",
434				 &dw9768->aac_mode);
435
436	/* Optional indication of clock pre-scale select */
437	fwnode_property_read_u32(dev_fwnode(dev), "dongwoon,clock-presc",
438				 &dw9768->clock_presc);
439
440	/* Optional indication of AAC Timing */
441	fwnode_property_read_u32(dev_fwnode(dev), "dongwoon,aac-timing",
442				 &dw9768->aac_timing);
443
444	dw9768->move_delay_us = dw9768_cal_move_delay(dw9768->aac_mode,
445						      dw9768->clock_presc,
446						      dw9768->aac_timing);
447
448	for (i = 0; i < ARRAY_SIZE(dw9768_supply_names); i++)
449		dw9768->supplies[i].supply = dw9768_supply_names[i];
450
451	ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(dw9768_supply_names),
452				      dw9768->supplies);
453	if (ret) {
454		dev_err(dev, "failed to get regulators\n");
455		return ret;
456	}
457
458	/* Initialize controls */
459	ret = dw9768_init_controls(dw9768);
460	if (ret)
461		goto err_free_handler;
462
463	/* Initialize subdev */
464	dw9768->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
465	dw9768->sd.internal_ops = &dw9768_int_ops;
466
467	ret = media_entity_pads_init(&dw9768->sd.entity, 0, NULL);
468	if (ret < 0)
469		goto err_free_handler;
470
471	dw9768->sd.entity.function = MEDIA_ENT_F_LENS;
472
473	/*
474	 * Figure out whether we're going to power up the device here. Generally
475	 * this is done if CONFIG_PM is disabled in a DT system or the device is
476	 * to be powered on in an ACPI system. Similarly for power off in
477	 * remove.
478	 */
479	pm_runtime_enable(dev);
480	full_power = (is_acpi_node(dev_fwnode(dev)) &&
481		      acpi_dev_state_d0(dev)) ||
482		     (is_of_node(dev_fwnode(dev)) && !pm_runtime_enabled(dev));
483	if (full_power) {
484		ret = dw9768_runtime_resume(dev);
485		if (ret < 0) {
486			dev_err(dev, "failed to power on: %d\n", ret);
487			goto err_clean_entity;
488		}
489		pm_runtime_set_active(dev);
490	}
491
492	ret = v4l2_async_register_subdev(&dw9768->sd);
493	if (ret < 0) {
494		dev_err(dev, "failed to register V4L2 subdev: %d", ret);
495		goto err_power_off;
496	}
497
498	pm_runtime_idle(dev);
499
500	return 0;
501
502err_power_off:
503	if (full_power) {
504		dw9768_runtime_suspend(dev);
505		pm_runtime_set_suspended(dev);
506	}
507err_clean_entity:
508	pm_runtime_disable(dev);
509	media_entity_cleanup(&dw9768->sd.entity);
510err_free_handler:
511	v4l2_ctrl_handler_free(&dw9768->ctrls);
512
513	return ret;
514}
515
516static void dw9768_remove(struct i2c_client *client)
517{
518	struct v4l2_subdev *sd = i2c_get_clientdata(client);
519	struct dw9768 *dw9768 = sd_to_dw9768(sd);
520	struct device *dev = &client->dev;
521
522	v4l2_async_unregister_subdev(&dw9768->sd);
523	v4l2_ctrl_handler_free(&dw9768->ctrls);
524	media_entity_cleanup(&dw9768->sd.entity);
525	if ((is_acpi_node(dev_fwnode(dev)) && acpi_dev_state_d0(dev)) ||
526	    (is_of_node(dev_fwnode(dev)) && !pm_runtime_enabled(dev))) {
527		dw9768_runtime_suspend(dev);
528		pm_runtime_set_suspended(dev);
529	}
530	pm_runtime_disable(dev);
531}
532
533static const struct of_device_id dw9768_of_table[] = {
534	{ .compatible = "dongwoon,dw9768" },
535	{ .compatible = "giantec,gt9769" },
536	{}
537};
538MODULE_DEVICE_TABLE(of, dw9768_of_table);
539
540static const struct dev_pm_ops dw9768_pm_ops = {
541	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
542				pm_runtime_force_resume)
543	SET_RUNTIME_PM_OPS(dw9768_runtime_suspend, dw9768_runtime_resume, NULL)
544};
545
546static struct i2c_driver dw9768_i2c_driver = {
547	.driver = {
548		.name = DW9768_NAME,
549		.pm = &dw9768_pm_ops,
550		.of_match_table = dw9768_of_table,
551	},
552	.probe = dw9768_probe,
553	.remove = dw9768_remove,
554};
555module_i2c_driver(dw9768_i2c_driver);
556
557MODULE_AUTHOR("Dongchun Zhu <dongchun.zhu@mediatek.com>");
558MODULE_DESCRIPTION("DW9768 VCM driver");
559MODULE_LICENSE("GPL v2");
560