1// SPDX-License-Identifier: GPL-2.0
2// Copyright (C) 2018 Intel Corporation
3
4#include <linux/acpi.h>
5#include <linux/delay.h>
6#include <linux/i2c.h>
7#include <linux/iopoll.h>
8#include <linux/module.h>
9#include <linux/pm_runtime.h>
10#include <media/v4l2-ctrls.h>
11#include <media/v4l2-device.h>
12
13#define DW9807_MAX_FOCUS_POS 1023
14/*
15 * This sets the minimum granularity for the focus positions.
16 * A value of 1 gives maximum accuracy for a desired focus position.
17 */
18#define DW9807_FOCUS_STEPS 1
19/*
20 * This acts as the minimum granularity of lens movement.
21 * Keep this value power of 2, so the control steps can be
22 * uniformly adjusted for gradual lens movement, with desired
23 * number of control steps.
24 */
25#define DW9807_CTRL_STEPS 16
26#define DW9807_CTRL_DELAY_US 1000
27
28#define DW9807_CTL_ADDR 0x02
29/*
30 * DW9807 separates two registers to control the VCM position.
31 * One for MSB value, another is LSB value.
32 */
33#define DW9807_MSB_ADDR 0x03
34#define DW9807_LSB_ADDR 0x04
35#define DW9807_STATUS_ADDR 0x05
36#define DW9807_MODE_ADDR 0x06
37#define DW9807_RESONANCE_ADDR 0x07
38
39#define MAX_RETRY 10
40
41struct dw9807_device {
42 struct v4l2_ctrl_handler ctrls_vcm;
43 struct v4l2_subdev sd;
44 u16 current_val;
45};
46
47static inline struct dw9807_device *sd_to_dw9807_vcm(
48 struct v4l2_subdev *subdev)
49{
50 return container_of(subdev, struct dw9807_device, sd);
51}
52
53static int dw9807_i2c_check(struct i2c_client *client)
54{
55 const char status_addr = DW9807_STATUS_ADDR;
56 char status_result;
57 int ret;
58
59 ret = i2c_master_send(client, buf: &status_addr, count: sizeof(status_addr));
60 if (ret < 0) {
61 dev_err(&client->dev, "I2C write STATUS address fail ret = %d\n",
62 ret);
63 return ret;
64 }
65
66 ret = i2c_master_recv(client, buf: &status_result, count: sizeof(status_result));
67 if (ret < 0) {
68 dev_err(&client->dev, "I2C read STATUS value fail ret = %d\n",
69 ret);
70 return ret;
71 }
72
73 return status_result;
74}
75
76static int dw9807_set_dac(struct i2c_client *client, u16 data)
77{
78 const char tx_data[3] = {
79 DW9807_MSB_ADDR, ((data >> 8) & 0x03), (data & 0xff)
80 };
81 int val, ret;
82
83 /*
84 * According to the datasheet, need to check the bus status before we
85 * write VCM position. This ensure that we really write the value
86 * into the register
87 */
88 ret = readx_poll_timeout(dw9807_i2c_check, client, val, val <= 0,
89 DW9807_CTRL_DELAY_US, MAX_RETRY * DW9807_CTRL_DELAY_US);
90
91 if (ret || val < 0) {
92 if (ret) {
93 dev_warn(&client->dev,
94 "Cannot do the write operation because VCM is busy\n");
95 }
96
97 return ret ? -EBUSY : val;
98 }
99
100 /* Write VCM position to registers */
101 ret = i2c_master_send(client, buf: tx_data, count: sizeof(tx_data));
102 if (ret < 0) {
103 dev_err(&client->dev,
104 "I2C write MSB fail ret=%d\n", ret);
105
106 return ret;
107 }
108
109 return 0;
110}
111
112static int dw9807_set_ctrl(struct v4l2_ctrl *ctrl)
113{
114 struct dw9807_device *dev_vcm = container_of(ctrl->handler,
115 struct dw9807_device, ctrls_vcm);
116
117 if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE) {
118 struct i2c_client *client = v4l2_get_subdevdata(sd: &dev_vcm->sd);
119
120 dev_vcm->current_val = ctrl->val;
121 return dw9807_set_dac(client, data: ctrl->val);
122 }
123
124 return -EINVAL;
125}
126
127static const struct v4l2_ctrl_ops dw9807_vcm_ctrl_ops = {
128 .s_ctrl = dw9807_set_ctrl,
129};
130
131static int dw9807_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
132{
133 return pm_runtime_resume_and_get(dev: sd->dev);
134}
135
136static int dw9807_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
137{
138 pm_runtime_put(dev: sd->dev);
139
140 return 0;
141}
142
143static const struct v4l2_subdev_internal_ops dw9807_int_ops = {
144 .open = dw9807_open,
145 .close = dw9807_close,
146};
147
148static const struct v4l2_subdev_ops dw9807_ops = { };
149
150static void dw9807_subdev_cleanup(struct dw9807_device *dw9807_dev)
151{
152 v4l2_async_unregister_subdev(sd: &dw9807_dev->sd);
153 v4l2_ctrl_handler_free(hdl: &dw9807_dev->ctrls_vcm);
154 media_entity_cleanup(entity: &dw9807_dev->sd.entity);
155}
156
157static int dw9807_init_controls(struct dw9807_device *dev_vcm)
158{
159 struct v4l2_ctrl_handler *hdl = &dev_vcm->ctrls_vcm;
160 const struct v4l2_ctrl_ops *ops = &dw9807_vcm_ctrl_ops;
161 struct i2c_client *client = v4l2_get_subdevdata(sd: &dev_vcm->sd);
162
163 v4l2_ctrl_handler_init(hdl, 1);
164
165 v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE,
166 min: 0, DW9807_MAX_FOCUS_POS, DW9807_FOCUS_STEPS, def: 0);
167
168 dev_vcm->sd.ctrl_handler = hdl;
169 if (hdl->error) {
170 dev_err(&client->dev, "%s fail error: 0x%x\n",
171 __func__, hdl->error);
172 return hdl->error;
173 }
174
175 return 0;
176}
177
178static int dw9807_probe(struct i2c_client *client)
179{
180 struct dw9807_device *dw9807_dev;
181 int rval;
182
183 dw9807_dev = devm_kzalloc(dev: &client->dev, size: sizeof(*dw9807_dev),
184 GFP_KERNEL);
185 if (dw9807_dev == NULL)
186 return -ENOMEM;
187
188 v4l2_i2c_subdev_init(sd: &dw9807_dev->sd, client, ops: &dw9807_ops);
189 dw9807_dev->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
190 dw9807_dev->sd.internal_ops = &dw9807_int_ops;
191
192 rval = dw9807_init_controls(dev_vcm: dw9807_dev);
193 if (rval)
194 goto err_cleanup;
195
196 rval = media_entity_pads_init(entity: &dw9807_dev->sd.entity, num_pads: 0, NULL);
197 if (rval < 0)
198 goto err_cleanup;
199
200 dw9807_dev->sd.entity.function = MEDIA_ENT_F_LENS;
201
202 rval = v4l2_async_register_subdev(sd: &dw9807_dev->sd);
203 if (rval < 0)
204 goto err_cleanup;
205
206 pm_runtime_set_active(dev: &client->dev);
207 pm_runtime_enable(dev: &client->dev);
208 pm_runtime_idle(dev: &client->dev);
209
210 return 0;
211
212err_cleanup:
213 v4l2_ctrl_handler_free(hdl: &dw9807_dev->ctrls_vcm);
214 media_entity_cleanup(entity: &dw9807_dev->sd.entity);
215
216 return rval;
217}
218
219static void dw9807_remove(struct i2c_client *client)
220{
221 struct v4l2_subdev *sd = i2c_get_clientdata(client);
222 struct dw9807_device *dw9807_dev = sd_to_dw9807_vcm(subdev: sd);
223
224 pm_runtime_disable(dev: &client->dev);
225
226 dw9807_subdev_cleanup(dw9807_dev);
227}
228
229/*
230 * This function sets the vcm position, so it consumes least current
231 * The lens position is gradually moved in units of DW9807_CTRL_STEPS,
232 * to make the movements smoothly.
233 */
234static int __maybe_unused dw9807_vcm_suspend(struct device *dev)
235{
236 struct i2c_client *client = to_i2c_client(dev);
237 struct v4l2_subdev *sd = i2c_get_clientdata(client);
238 struct dw9807_device *dw9807_dev = sd_to_dw9807_vcm(subdev: sd);
239 const char tx_data[2] = { DW9807_CTL_ADDR, 0x01 };
240 int ret, val;
241
242 for (val = dw9807_dev->current_val & ~(DW9807_CTRL_STEPS - 1);
243 val >= 0; val -= DW9807_CTRL_STEPS) {
244 ret = dw9807_set_dac(client, data: val);
245 if (ret)
246 dev_err_once(dev, "%s I2C failure: %d", __func__, ret);
247 usleep_range(DW9807_CTRL_DELAY_US, DW9807_CTRL_DELAY_US + 10);
248 }
249
250 /* Power down */
251 ret = i2c_master_send(client, buf: tx_data, count: sizeof(tx_data));
252 if (ret < 0) {
253 dev_err(&client->dev, "I2C write CTL fail ret = %d\n", ret);
254 return ret;
255 }
256
257 return 0;
258}
259
260/*
261 * This function sets the vcm position to the value set by the user
262 * through v4l2_ctrl_ops s_ctrl handler
263 * The lens position is gradually moved in units of DW9807_CTRL_STEPS,
264 * to make the movements smoothly.
265 */
266static int __maybe_unused dw9807_vcm_resume(struct device *dev)
267{
268 struct i2c_client *client = to_i2c_client(dev);
269 struct v4l2_subdev *sd = i2c_get_clientdata(client);
270 struct dw9807_device *dw9807_dev = sd_to_dw9807_vcm(subdev: sd);
271 const char tx_data[2] = { DW9807_CTL_ADDR, 0x00 };
272 int ret, val;
273
274 /* Power on */
275 ret = i2c_master_send(client, buf: tx_data, count: sizeof(tx_data));
276 if (ret < 0) {
277 dev_err(&client->dev, "I2C write CTL fail ret = %d\n", ret);
278 return ret;
279 }
280
281 for (val = dw9807_dev->current_val % DW9807_CTRL_STEPS;
282 val < dw9807_dev->current_val + DW9807_CTRL_STEPS - 1;
283 val += DW9807_CTRL_STEPS) {
284 ret = dw9807_set_dac(client, data: val);
285 if (ret)
286 dev_err_ratelimited(dev, "%s I2C failure: %d",
287 __func__, ret);
288 usleep_range(DW9807_CTRL_DELAY_US, DW9807_CTRL_DELAY_US + 10);
289 }
290
291 return 0;
292}
293
294static const struct of_device_id dw9807_of_table[] = {
295 { .compatible = "dongwoon,dw9807-vcm" },
296 /* Compatibility for older firmware, NEVER USE THIS IN FIRMWARE! */
297 { .compatible = "dongwoon,dw9807" },
298 { /* sentinel */ }
299};
300MODULE_DEVICE_TABLE(of, dw9807_of_table);
301
302static const struct dev_pm_ops dw9807_pm_ops = {
303 SET_SYSTEM_SLEEP_PM_OPS(dw9807_vcm_suspend, dw9807_vcm_resume)
304 SET_RUNTIME_PM_OPS(dw9807_vcm_suspend, dw9807_vcm_resume, NULL)
305};
306
307static struct i2c_driver dw9807_i2c_driver = {
308 .driver = {
309 .name = "dw9807",
310 .pm = &dw9807_pm_ops,
311 .of_match_table = dw9807_of_table,
312 },
313 .probe = dw9807_probe,
314 .remove = dw9807_remove,
315};
316
317module_i2c_driver(dw9807_i2c_driver);
318
319MODULE_AUTHOR("Chiang, Alan");
320MODULE_DESCRIPTION("DW9807 VCM driver");
321MODULE_LICENSE("GPL v2");
322

source code of linux/drivers/media/i2c/dw9807-vcm.c