xref: /linux/drivers/media/i2c/dw9714.c (revision 746680ec6696585e30db3e18c93a63df9cbec39c)
1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (c) 2015--2017 Intel Corporation.
3 
4 #include <linux/delay.h>
5 #include <linux/gpio/consumer.h>
6 #include <linux/i2c.h>
7 #include <linux/module.h>
8 #include <linux/pm_runtime.h>
9 #include <linux/regulator/consumer.h>
10 #include <media/v4l2-ctrls.h>
11 #include <media/v4l2-device.h>
12 #include <media/v4l2-event.h>
13 
14 #define DW9714_NAME		"dw9714"
15 #define DW9714_MAX_FOCUS_POS	1023
16 /*
17  * This sets the minimum granularity for the focus positions.
18  * A value of 1 gives maximum accuracy for a desired focus position
19  */
20 #define DW9714_FOCUS_STEPS	1
21 /*
22  * This acts as the minimum granularity of lens movement.
23  * Keep this value power of 2, so the control steps can be
24  * uniformly adjusted for gradual lens movement, with desired
25  * number of control steps.
26  */
27 #define DW9714_CTRL_STEPS	16
28 #define DW9714_CTRL_DELAY_US	1000
29 /*
30  * S[3:2] = 0x00, codes per step for "Linear Slope Control"
31  * S[1:0] = 0x00, step period
32  */
33 #define DW9714_DEFAULT_S 0x0
34 #define DW9714_VAL(data, s) ((data) << 4 | (s))
35 
36 /* dw9714 device structure */
37 struct dw9714_device {
38 	struct v4l2_ctrl_handler ctrls_vcm;
39 	struct v4l2_subdev sd;
40 	u16 current_val;
41 	struct regulator *vcc;
42 	struct gpio_desc *powerdown_gpio;
43 };
44 
45 static inline struct dw9714_device *to_dw9714_vcm(struct v4l2_ctrl *ctrl)
46 {
47 	return container_of(ctrl->handler, struct dw9714_device, ctrls_vcm);
48 }
49 
50 static inline struct dw9714_device *sd_to_dw9714_vcm(struct v4l2_subdev *subdev)
51 {
52 	return container_of(subdev, struct dw9714_device, sd);
53 }
54 
55 static int dw9714_i2c_write(struct i2c_client *client, u16 data)
56 {
57 	int ret;
58 	__be16 val = cpu_to_be16(data);
59 
60 	ret = i2c_master_send(client, (const char *)&val, sizeof(val));
61 	if (ret != sizeof(val)) {
62 		dev_err(&client->dev, "I2C write fail\n");
63 		return -EIO;
64 	}
65 	return 0;
66 }
67 
68 static int dw9714_t_focus_vcm(struct dw9714_device *dw9714_dev, u16 val)
69 {
70 	struct i2c_client *client = v4l2_get_subdevdata(&dw9714_dev->sd);
71 
72 	dw9714_dev->current_val = val;
73 
74 	return dw9714_i2c_write(client, DW9714_VAL(val, DW9714_DEFAULT_S));
75 }
76 
77 static int dw9714_set_ctrl(struct v4l2_ctrl *ctrl)
78 {
79 	struct dw9714_device *dev_vcm = to_dw9714_vcm(ctrl);
80 
81 	if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE)
82 		return dw9714_t_focus_vcm(dev_vcm, ctrl->val);
83 
84 	return -EINVAL;
85 }
86 
87 static const struct v4l2_ctrl_ops dw9714_vcm_ctrl_ops = {
88 	.s_ctrl = dw9714_set_ctrl,
89 };
90 
91 static int dw9714_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
92 {
93 	return pm_runtime_resume_and_get(sd->dev);
94 }
95 
96 static int dw9714_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
97 {
98 	pm_runtime_put(sd->dev);
99 
100 	return 0;
101 }
102 
103 static const struct v4l2_subdev_internal_ops dw9714_int_ops = {
104 	.open = dw9714_open,
105 	.close = dw9714_close,
106 };
107 
108 static const struct v4l2_subdev_core_ops dw9714_core_ops = {
109 	.log_status = v4l2_ctrl_subdev_log_status,
110 	.subscribe_event = v4l2_ctrl_subdev_subscribe_event,
111 	.unsubscribe_event = v4l2_event_subdev_unsubscribe,
112 };
113 
114 static const struct v4l2_subdev_ops dw9714_ops = {
115 	.core = &dw9714_core_ops,
116 };
117 
118 static void dw9714_subdev_cleanup(struct dw9714_device *dw9714_dev)
119 {
120 	v4l2_async_unregister_subdev(&dw9714_dev->sd);
121 	v4l2_ctrl_handler_free(&dw9714_dev->ctrls_vcm);
122 	media_entity_cleanup(&dw9714_dev->sd.entity);
123 }
124 
125 static int dw9714_init_controls(struct dw9714_device *dev_vcm)
126 {
127 	struct v4l2_ctrl_handler *hdl = &dev_vcm->ctrls_vcm;
128 	const struct v4l2_ctrl_ops *ops = &dw9714_vcm_ctrl_ops;
129 
130 	v4l2_ctrl_handler_init(hdl, 1);
131 
132 	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE,
133 			  0, DW9714_MAX_FOCUS_POS, DW9714_FOCUS_STEPS, 0);
134 
135 	if (hdl->error)
136 		dev_err(dev_vcm->sd.dev, "%s fail error: 0x%x\n",
137 			__func__, hdl->error);
138 	dev_vcm->sd.ctrl_handler = hdl;
139 	return hdl->error;
140 }
141 
142 static int dw9714_power_up(struct dw9714_device *dw9714_dev)
143 {
144 	int ret;
145 
146 	ret = regulator_enable(dw9714_dev->vcc);
147 	if (ret)
148 		return ret;
149 
150 	gpiod_set_value_cansleep(dw9714_dev->powerdown_gpio, 0);
151 
152 	usleep_range(1000, 2000);
153 
154 	return 0;
155 }
156 
157 static int dw9714_power_down(struct dw9714_device *dw9714_dev)
158 {
159 	gpiod_set_value_cansleep(dw9714_dev->powerdown_gpio, 1);
160 
161 	return regulator_disable(dw9714_dev->vcc);
162 }
163 
164 static int dw9714_probe(struct i2c_client *client)
165 {
166 	struct dw9714_device *dw9714_dev;
167 	int rval;
168 
169 	dw9714_dev = devm_kzalloc(&client->dev, sizeof(*dw9714_dev),
170 				  GFP_KERNEL);
171 	if (!dw9714_dev)
172 		return -ENOMEM;
173 
174 	dw9714_dev->vcc = devm_regulator_get(&client->dev, "vcc");
175 	if (IS_ERR(dw9714_dev->vcc))
176 		return PTR_ERR(dw9714_dev->vcc);
177 
178 	dw9714_dev->powerdown_gpio = devm_gpiod_get_optional(&client->dev,
179 							     "powerdown",
180 							     GPIOD_OUT_HIGH);
181 	if (IS_ERR(dw9714_dev->powerdown_gpio))
182 		return dev_err_probe(&client->dev,
183 				     PTR_ERR(dw9714_dev->powerdown_gpio),
184 				     "could not get powerdown gpio\n");
185 
186 	rval = dw9714_power_up(dw9714_dev);
187 	if (rval)
188 		return dev_err_probe(&client->dev, rval,
189 				     "failed to power up: %d\n", rval);
190 
191 	v4l2_i2c_subdev_init(&dw9714_dev->sd, client, &dw9714_ops);
192 	dw9714_dev->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
193 				V4L2_SUBDEV_FL_HAS_EVENTS;
194 	dw9714_dev->sd.internal_ops = &dw9714_int_ops;
195 
196 	rval = dw9714_init_controls(dw9714_dev);
197 	if (rval)
198 		goto err_cleanup;
199 
200 	rval = media_entity_pads_init(&dw9714_dev->sd.entity, 0, NULL);
201 	if (rval < 0)
202 		goto err_cleanup;
203 
204 	dw9714_dev->sd.entity.function = MEDIA_ENT_F_LENS;
205 
206 	rval = v4l2_async_register_subdev(&dw9714_dev->sd);
207 	if (rval < 0)
208 		goto err_cleanup;
209 
210 	pm_runtime_set_active(&client->dev);
211 	pm_runtime_enable(&client->dev);
212 	pm_runtime_idle(&client->dev);
213 
214 	return 0;
215 
216 err_cleanup:
217 	dw9714_power_down(dw9714_dev);
218 	v4l2_ctrl_handler_free(&dw9714_dev->ctrls_vcm);
219 	media_entity_cleanup(&dw9714_dev->sd.entity);
220 
221 	return rval;
222 }
223 
224 static void dw9714_remove(struct i2c_client *client)
225 {
226 	struct v4l2_subdev *sd = i2c_get_clientdata(client);
227 	struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
228 	int ret;
229 
230 	pm_runtime_disable(&client->dev);
231 	if (!pm_runtime_status_suspended(&client->dev)) {
232 		ret = dw9714_power_down(dw9714_dev);
233 		if (ret) {
234 			dev_err(&client->dev,
235 				"Failed to power down: %d\n", ret);
236 		}
237 	}
238 	pm_runtime_set_suspended(&client->dev);
239 	dw9714_subdev_cleanup(dw9714_dev);
240 }
241 
242 /*
243  * This function sets the vcm position, so it consumes least current
244  * The lens position is gradually moved in units of DW9714_CTRL_STEPS,
245  * to make the movements smoothly.
246  */
247 static int __maybe_unused dw9714_vcm_suspend(struct device *dev)
248 {
249 	struct i2c_client *client = to_i2c_client(dev);
250 	struct v4l2_subdev *sd = i2c_get_clientdata(client);
251 	struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
252 	int ret, val;
253 
254 	if (pm_runtime_suspended(&client->dev))
255 		return 0;
256 
257 	for (val = dw9714_dev->current_val & ~(DW9714_CTRL_STEPS - 1);
258 	     val >= 0; val -= DW9714_CTRL_STEPS) {
259 		ret = dw9714_i2c_write(client,
260 				       DW9714_VAL(val, DW9714_DEFAULT_S));
261 		if (ret)
262 			dev_err_once(dev, "%s I2C failure: %d", __func__, ret);
263 		usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10);
264 	}
265 
266 	ret = dw9714_power_down(dw9714_dev);
267 	if (ret)
268 		dev_err(dev, "Failed to power down: %d\n", ret);
269 
270 	return ret;
271 }
272 
273 /*
274  * This function sets the vcm position to the value set by the user
275  * through v4l2_ctrl_ops s_ctrl handler
276  * The lens position is gradually moved in units of DW9714_CTRL_STEPS,
277  * to make the movements smoothly.
278  */
279 static int __maybe_unused dw9714_vcm_resume(struct device *dev)
280 {
281 	struct i2c_client *client = to_i2c_client(dev);
282 	struct v4l2_subdev *sd = i2c_get_clientdata(client);
283 	struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
284 	int ret, val;
285 
286 	if (pm_runtime_suspended(&client->dev))
287 		return 0;
288 
289 	ret = dw9714_power_up(dw9714_dev);
290 	if (ret) {
291 		dev_err(dev, "Failed to power up: %d\n", ret);
292 		return ret;
293 	}
294 
295 	for (val = dw9714_dev->current_val % DW9714_CTRL_STEPS;
296 	     val < dw9714_dev->current_val + DW9714_CTRL_STEPS - 1;
297 	     val += DW9714_CTRL_STEPS) {
298 		ret = dw9714_i2c_write(client,
299 				       DW9714_VAL(val, DW9714_DEFAULT_S));
300 		if (ret)
301 			dev_err_ratelimited(dev, "%s I2C failure: %d",
302 					    __func__, ret);
303 		usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10);
304 	}
305 
306 	return 0;
307 }
308 
309 static const struct i2c_device_id dw9714_id_table[] = {
310 	{ DW9714_NAME },
311 	{ }
312 };
313 MODULE_DEVICE_TABLE(i2c, dw9714_id_table);
314 
315 static const struct of_device_id dw9714_of_table[] = {
316 	{ .compatible = "dongwoon,dw9714" },
317 	{ { 0 } }
318 };
319 MODULE_DEVICE_TABLE(of, dw9714_of_table);
320 
321 static const struct dev_pm_ops dw9714_pm_ops = {
322 	SET_SYSTEM_SLEEP_PM_OPS(dw9714_vcm_suspend, dw9714_vcm_resume)
323 	SET_RUNTIME_PM_OPS(dw9714_vcm_suspend, dw9714_vcm_resume, NULL)
324 };
325 
326 static struct i2c_driver dw9714_i2c_driver = {
327 	.driver = {
328 		.name = DW9714_NAME,
329 		.pm = &dw9714_pm_ops,
330 		.of_match_table = dw9714_of_table,
331 	},
332 	.probe = dw9714_probe,
333 	.remove = dw9714_remove,
334 	.id_table = dw9714_id_table,
335 };
336 
337 module_i2c_driver(dw9714_i2c_driver);
338 
339 MODULE_AUTHOR("Tianshu Qiu <tian.shu.qiu@intel.com>");
340 MODULE_AUTHOR("Jian Xu Zheng");
341 MODULE_AUTHOR("Yuning Pu");
342 MODULE_AUTHOR("Jouni Ukkonen");
343 MODULE_AUTHOR("Tommi Franttila");
344 MODULE_DESCRIPTION("DW9714 VCM driver");
345 MODULE_LICENSE("GPL v2");
346