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	v4l2_i2c_subdev_init(&dw9714_dev->sd, client, &dw9714_ops);
161	dw9714_dev->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
162				V4L2_SUBDEV_FL_HAS_EVENTS;
163	dw9714_dev->sd.internal_ops = &dw9714_int_ops;
164
165	rval = dw9714_init_controls(dw9714_dev);
166	if (rval)
167		goto err_cleanup;
168
169	rval = media_entity_pads_init(&dw9714_dev->sd.entity, 0, NULL);
170	if (rval < 0)
171		goto err_cleanup;
172
173	dw9714_dev->sd.entity.function = MEDIA_ENT_F_LENS;
174
175	rval = v4l2_async_register_subdev(&dw9714_dev->sd);
176	if (rval < 0)
177		goto err_cleanup;
178
179	pm_runtime_set_active(&client->dev);
180	pm_runtime_enable(&client->dev);
181	pm_runtime_idle(&client->dev);
182
183	return 0;
184
185err_cleanup:
186	regulator_disable(dw9714_dev->vcc);
187	v4l2_ctrl_handler_free(&dw9714_dev->ctrls_vcm);
188	media_entity_cleanup(&dw9714_dev->sd.entity);
189
190	return rval;
191}
192
193static void dw9714_remove(struct i2c_client *client)
194{
195	struct v4l2_subdev *sd = i2c_get_clientdata(client);
196	struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
197	int ret;
198
199	pm_runtime_disable(&client->dev);
200	if (!pm_runtime_status_suspended(&client->dev)) {
201		ret = regulator_disable(dw9714_dev->vcc);
202		if (ret) {
203			dev_err(&client->dev,
204				"Failed to disable vcc: %d\n", ret);
205		}
206	}
207	pm_runtime_set_suspended(&client->dev);
208	dw9714_subdev_cleanup(dw9714_dev);
209}
210
211/*
212 * This function sets the vcm position, so it consumes least current
213 * The lens position is gradually moved in units of DW9714_CTRL_STEPS,
214 * to make the movements smoothly.
215 */
216static int __maybe_unused dw9714_vcm_suspend(struct device *dev)
217{
218	struct i2c_client *client = to_i2c_client(dev);
219	struct v4l2_subdev *sd = i2c_get_clientdata(client);
220	struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
221	int ret, val;
222
223	if (pm_runtime_suspended(&client->dev))
224		return 0;
225
226	for (val = dw9714_dev->current_val & ~(DW9714_CTRL_STEPS - 1);
227	     val >= 0; val -= DW9714_CTRL_STEPS) {
228		ret = dw9714_i2c_write(client,
229				       DW9714_VAL(val, DW9714_DEFAULT_S));
230		if (ret)
231			dev_err_once(dev, "%s I2C failure: %d", __func__, ret);
232		usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10);
233	}
234
235	ret = regulator_disable(dw9714_dev->vcc);
236	if (ret)
237		dev_err(dev, "Failed to disable vcc: %d\n", ret);
238
239	return ret;
240}
241
242/*
243 * This function sets the vcm position to the value set by the user
244 * through v4l2_ctrl_ops s_ctrl handler
245 * The lens position is gradually moved in units of DW9714_CTRL_STEPS,
246 * to make the movements smoothly.
247 */
248static int  __maybe_unused dw9714_vcm_resume(struct device *dev)
249{
250	struct i2c_client *client = to_i2c_client(dev);
251	struct v4l2_subdev *sd = i2c_get_clientdata(client);
252	struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
253	int ret, val;
254
255	if (pm_runtime_suspended(&client->dev))
256		return 0;
257
258	ret = regulator_enable(dw9714_dev->vcc);
259	if (ret) {
260		dev_err(dev, "Failed to enable vcc: %d\n", ret);
261		return ret;
262	}
263	usleep_range(1000, 2000);
264
265	for (val = dw9714_dev->current_val % DW9714_CTRL_STEPS;
266	     val < dw9714_dev->current_val + DW9714_CTRL_STEPS - 1;
267	     val += DW9714_CTRL_STEPS) {
268		ret = dw9714_i2c_write(client,
269				       DW9714_VAL(val, DW9714_DEFAULT_S));
270		if (ret)
271			dev_err_ratelimited(dev, "%s I2C failure: %d",
272						__func__, ret);
273		usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10);
274	}
275
276	return 0;
277}
278
279static const struct i2c_device_id dw9714_id_table[] = {
280	{ DW9714_NAME, 0 },
281	{ { 0 } }
282};
283MODULE_DEVICE_TABLE(i2c, dw9714_id_table);
284
285static const struct of_device_id dw9714_of_table[] = {
286	{ .compatible = "dongwoon,dw9714" },
287	{ { 0 } }
288};
289MODULE_DEVICE_TABLE(of, dw9714_of_table);
290
291static const struct dev_pm_ops dw9714_pm_ops = {
292	SET_SYSTEM_SLEEP_PM_OPS(dw9714_vcm_suspend, dw9714_vcm_resume)
293	SET_RUNTIME_PM_OPS(dw9714_vcm_suspend, dw9714_vcm_resume, NULL)
294};
295
296static struct i2c_driver dw9714_i2c_driver = {
297	.driver = {
298		.name = DW9714_NAME,
299		.pm = &dw9714_pm_ops,
300		.of_match_table = dw9714_of_table,
301	},
302	.probe = dw9714_probe,
303	.remove = dw9714_remove,
304	.id_table = dw9714_id_table,
305};
306
307module_i2c_driver(dw9714_i2c_driver);
308
309MODULE_AUTHOR("Tianshu Qiu <tian.shu.qiu@intel.com>");
310MODULE_AUTHOR("Jian Xu Zheng");
311MODULE_AUTHOR("Yuning Pu <yuning.pu@intel.com>");
312MODULE_AUTHOR("Jouni Ukkonen <jouni.ukkonen@intel.com>");
313MODULE_AUTHOR("Tommi Franttila <tommi.franttila@intel.com>");
314MODULE_DESCRIPTION("DW9714 VCM driver");
315MODULE_LICENSE("GPL v2");
316