1// SPDX-License-Identifier: GPL-2.0
2// Copyright (c) 2015--2017 Intel Corporation.
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-ctrls.h>
10#include <media/v4l2-device.h>
11#include <media/v4l2-event.h>
12
13#define DW9714_NAME		"dw9714"
14#define DW9714_MAX_FOCUS_POS	1023
15/*
16 * This sets the minimum granularity for the focus positions.
17 * A value of 1 gives maximum accuracy for a desired focus position
18 */
19#define DW9714_FOCUS_STEPS	1
20/*
21 * This acts as the minimum granularity of lens movement.
22 * Keep this value power of 2, so the control steps can be
23 * uniformly adjusted for gradual lens movement, with desired
24 * number of control steps.
25 */
26#define DW9714_CTRL_STEPS	16
27#define DW9714_CTRL_DELAY_US	1000
28/*
29 * S[3:2] = 0x00, codes per step for "Linear Slope Control"
30 * S[1:0] = 0x00, step period
31 */
32#define DW9714_DEFAULT_S 0x0
33#define DW9714_VAL(data, s) ((data) << 4 | (s))
34
35/* dw9714 device structure */
36struct dw9714_device {
37	struct v4l2_ctrl_handler ctrls_vcm;
38	struct v4l2_subdev sd;
39	u16 current_val;
40	struct regulator *vcc;
41};
42
43static inline struct dw9714_device *to_dw9714_vcm(struct v4l2_ctrl *ctrl)
44{
45	return container_of(ctrl->handler, struct dw9714_device, ctrls_vcm);
46}
47
48static inline struct dw9714_device *sd_to_dw9714_vcm(struct v4l2_subdev *subdev)
49{
50	return container_of(subdev, struct dw9714_device, sd);
51}
52
53static int dw9714_i2c_write(struct i2c_client *client, u16 data)
54{
55	int ret;
56	__be16 val = cpu_to_be16(data);
57
58	ret = i2c_master_send(client, (const char *)&val, sizeof(val));
59	if (ret != sizeof(val)) {
60		dev_err(&client->dev, "I2C write fail\n");
61		return -EIO;
62	}
63	return 0;
64}
65
66static int dw9714_t_focus_vcm(struct dw9714_device *dw9714_dev, u16 val)
67{
68	struct i2c_client *client = v4l2_get_subdevdata(&dw9714_dev->sd);
69
70	dw9714_dev->current_val = val;
71
72	return dw9714_i2c_write(client, DW9714_VAL(val, DW9714_DEFAULT_S));
73}
74
75static int dw9714_set_ctrl(struct v4l2_ctrl *ctrl)
76{
77	struct dw9714_device *dev_vcm = to_dw9714_vcm(ctrl);
78
79	if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE)
80		return dw9714_t_focus_vcm(dev_vcm, ctrl->val);
81
82	return -EINVAL;
83}
84
85static const struct v4l2_ctrl_ops dw9714_vcm_ctrl_ops = {
86	.s_ctrl = dw9714_set_ctrl,
87};
88
89static int dw9714_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
90{
91	return pm_runtime_resume_and_get(sd->dev);
92}
93
94static int dw9714_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
95{
96	pm_runtime_put(sd->dev);
97
98	return 0;
99}
100
101static const struct v4l2_subdev_internal_ops dw9714_int_ops = {
102	.open = dw9714_open,
103	.close = dw9714_close,
104};
105
106static const struct v4l2_subdev_core_ops dw9714_core_ops = {
107	.log_status = v4l2_ctrl_subdev_log_status,
108	.subscribe_event = v4l2_ctrl_subdev_subscribe_event,
109	.unsubscribe_event = v4l2_event_subdev_unsubscribe,
110};
111
112static const struct v4l2_subdev_ops dw9714_ops = {
113	.core = &dw9714_core_ops,
114};
115
116static void dw9714_subdev_cleanup(struct dw9714_device *dw9714_dev)
117{
118	v4l2_async_unregister_subdev(&dw9714_dev->sd);
119	v4l2_ctrl_handler_free(&dw9714_dev->ctrls_vcm);
120	media_entity_cleanup(&dw9714_dev->sd.entity);
121}
122
123static int dw9714_init_controls(struct dw9714_device *dev_vcm)
124{
125	struct v4l2_ctrl_handler *hdl = &dev_vcm->ctrls_vcm;
126	const struct v4l2_ctrl_ops *ops = &dw9714_vcm_ctrl_ops;
127
128	v4l2_ctrl_handler_init(hdl, 1);
129
130	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE,
131			  0, DW9714_MAX_FOCUS_POS, DW9714_FOCUS_STEPS, 0);
132
133	if (hdl->error)
134		dev_err(dev_vcm->sd.dev, "%s fail error: 0x%x\n",
135			__func__, hdl->error);
136	dev_vcm->sd.ctrl_handler = hdl;
137	return hdl->error;
138}
139
140static int dw9714_probe(struct i2c_client *client)
141{
142	struct dw9714_device *dw9714_dev;
143	int rval;
144
145	dw9714_dev = devm_kzalloc(&client->dev, sizeof(*dw9714_dev),
146				  GFP_KERNEL);
147	if (dw9714_dev == NULL)
148		return -ENOMEM;
149
150	dw9714_dev->vcc = devm_regulator_get(&client->dev, "vcc");
151	if (IS_ERR(dw9714_dev->vcc))
152		return PTR_ERR(dw9714_dev->vcc);
153
154	rval = regulator_enable(dw9714_dev->vcc);
155	if (rval < 0) {
156		dev_err(&client->dev, "failed to enable vcc: %d\n", rval);
157		return rval;
158	}
159
160	usleep_range(1000, 2000);
161
162	v4l2_i2c_subdev_init(&dw9714_dev->sd, client, &dw9714_ops);
163	dw9714_dev->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
164				V4L2_SUBDEV_FL_HAS_EVENTS;
165	dw9714_dev->sd.internal_ops = &dw9714_int_ops;
166
167	rval = dw9714_init_controls(dw9714_dev);
168	if (rval)
169		goto err_cleanup;
170
171	rval = media_entity_pads_init(&dw9714_dev->sd.entity, 0, NULL);
172	if (rval < 0)
173		goto err_cleanup;
174
175	dw9714_dev->sd.entity.function = MEDIA_ENT_F_LENS;
176
177	rval = v4l2_async_register_subdev(&dw9714_dev->sd);
178	if (rval < 0)
179		goto err_cleanup;
180
181	pm_runtime_set_active(&client->dev);
182	pm_runtime_enable(&client->dev);
183	pm_runtime_idle(&client->dev);
184
185	return 0;
186
187err_cleanup:
188	regulator_disable(dw9714_dev->vcc);
189	v4l2_ctrl_handler_free(&dw9714_dev->ctrls_vcm);
190	media_entity_cleanup(&dw9714_dev->sd.entity);
191
192	return rval;
193}
194
195static void dw9714_remove(struct i2c_client *client)
196{
197	struct v4l2_subdev *sd = i2c_get_clientdata(client);
198	struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
199	int ret;
200
201	pm_runtime_disable(&client->dev);
202	if (!pm_runtime_status_suspended(&client->dev)) {
203		ret = regulator_disable(dw9714_dev->vcc);
204		if (ret) {
205			dev_err(&client->dev,
206				"Failed to disable vcc: %d\n", ret);
207		}
208	}
209	pm_runtime_set_suspended(&client->dev);
210	dw9714_subdev_cleanup(dw9714_dev);
211}
212
213/*
214 * This function sets the vcm position, so it consumes least current
215 * The lens position is gradually moved in units of DW9714_CTRL_STEPS,
216 * to make the movements smoothly.
217 */
218static int __maybe_unused dw9714_vcm_suspend(struct device *dev)
219{
220	struct i2c_client *client = to_i2c_client(dev);
221	struct v4l2_subdev *sd = i2c_get_clientdata(client);
222	struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
223	int ret, val;
224
225	if (pm_runtime_suspended(&client->dev))
226		return 0;
227
228	for (val = dw9714_dev->current_val & ~(DW9714_CTRL_STEPS - 1);
229	     val >= 0; val -= DW9714_CTRL_STEPS) {
230		ret = dw9714_i2c_write(client,
231				       DW9714_VAL(val, DW9714_DEFAULT_S));
232		if (ret)
233			dev_err_once(dev, "%s I2C failure: %d", __func__, ret);
234		usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10);
235	}
236
237	ret = regulator_disable(dw9714_dev->vcc);
238	if (ret)
239		dev_err(dev, "Failed to disable vcc: %d\n", ret);
240
241	return ret;
242}
243
244/*
245 * This function sets the vcm position to the value set by the user
246 * through v4l2_ctrl_ops s_ctrl handler
247 * The lens position is gradually moved in units of DW9714_CTRL_STEPS,
248 * to make the movements smoothly.
249 */
250static int  __maybe_unused dw9714_vcm_resume(struct device *dev)
251{
252	struct i2c_client *client = to_i2c_client(dev);
253	struct v4l2_subdev *sd = i2c_get_clientdata(client);
254	struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
255	int ret, val;
256
257	if (pm_runtime_suspended(&client->dev))
258		return 0;
259
260	ret = regulator_enable(dw9714_dev->vcc);
261	if (ret) {
262		dev_err(dev, "Failed to enable vcc: %d\n", ret);
263		return ret;
264	}
265	usleep_range(1000, 2000);
266
267	for (val = dw9714_dev->current_val % DW9714_CTRL_STEPS;
268	     val < dw9714_dev->current_val + DW9714_CTRL_STEPS - 1;
269	     val += DW9714_CTRL_STEPS) {
270		ret = dw9714_i2c_write(client,
271				       DW9714_VAL(val, DW9714_DEFAULT_S));
272		if (ret)
273			dev_err_ratelimited(dev, "%s I2C failure: %d",
274						__func__, ret);
275		usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10);
276	}
277
278	return 0;
279}
280
281static const struct i2c_device_id dw9714_id_table[] = {
282	{ DW9714_NAME, 0 },
283	{ { 0 } }
284};
285MODULE_DEVICE_TABLE(i2c, dw9714_id_table);
286
287static const struct of_device_id dw9714_of_table[] = {
288	{ .compatible = "dongwoon,dw9714" },
289	{ { 0 } }
290};
291MODULE_DEVICE_TABLE(of, dw9714_of_table);
292
293static const struct dev_pm_ops dw9714_pm_ops = {
294	SET_SYSTEM_SLEEP_PM_OPS(dw9714_vcm_suspend, dw9714_vcm_resume)
295	SET_RUNTIME_PM_OPS(dw9714_vcm_suspend, dw9714_vcm_resume, NULL)
296};
297
298static struct i2c_driver dw9714_i2c_driver = {
299	.driver = {
300		.name = DW9714_NAME,
301		.pm = &dw9714_pm_ops,
302		.of_match_table = dw9714_of_table,
303	},
304	.probe = dw9714_probe,
305	.remove = dw9714_remove,
306	.id_table = dw9714_id_table,
307};
308
309module_i2c_driver(dw9714_i2c_driver);
310
311MODULE_AUTHOR("Tianshu Qiu <tian.shu.qiu@intel.com>");
312MODULE_AUTHOR("Jian Xu Zheng");
313MODULE_AUTHOR("Yuning Pu <yuning.pu@intel.com>");
314MODULE_AUTHOR("Jouni Ukkonen <jouni.ukkonen@intel.com>");
315MODULE_AUTHOR("Tommi Franttila <tommi.franttila@intel.com>");
316MODULE_DESCRIPTION("DW9714 VCM driver");
317MODULE_LICENSE("GPL v2");
318