xref: /openbmc/linux/drivers/media/i2c/dw9714.c (revision a2818ee4)
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 <media/v4l2-ctrls.h>
9 #include <media/v4l2-device.h>
10 
11 #define DW9714_NAME		"dw9714"
12 #define DW9714_MAX_FOCUS_POS	1023
13 /*
14  * This sets the minimum granularity for the focus positions.
15  * A value of 1 gives maximum accuracy for a desired focus position
16  */
17 #define DW9714_FOCUS_STEPS	1
18 /*
19  * This acts as the minimum granularity of lens movement.
20  * Keep this value power of 2, so the control steps can be
21  * uniformly adjusted for gradual lens movement, with desired
22  * number of control steps.
23  */
24 #define DW9714_CTRL_STEPS	16
25 #define DW9714_CTRL_DELAY_US	1000
26 /*
27  * S[3:2] = 0x00, codes per step for "Linear Slope Control"
28  * S[1:0] = 0x00, step period
29  */
30 #define DW9714_DEFAULT_S 0x0
31 #define DW9714_VAL(data, s) ((data) << 4 | (s))
32 
33 /* dw9714 device structure */
34 struct dw9714_device {
35 	struct v4l2_ctrl_handler ctrls_vcm;
36 	struct v4l2_subdev sd;
37 	u16 current_val;
38 };
39 
40 static inline struct dw9714_device *to_dw9714_vcm(struct v4l2_ctrl *ctrl)
41 {
42 	return container_of(ctrl->handler, struct dw9714_device, ctrls_vcm);
43 }
44 
45 static inline struct dw9714_device *sd_to_dw9714_vcm(struct v4l2_subdev *subdev)
46 {
47 	return container_of(subdev, struct dw9714_device, sd);
48 }
49 
50 static int dw9714_i2c_write(struct i2c_client *client, u16 data)
51 {
52 	int ret;
53 	__be16 val = cpu_to_be16(data);
54 
55 	ret = i2c_master_send(client, (const char *)&val, sizeof(val));
56 	if (ret != sizeof(val)) {
57 		dev_err(&client->dev, "I2C write fail\n");
58 		return -EIO;
59 	}
60 	return 0;
61 }
62 
63 static int dw9714_t_focus_vcm(struct dw9714_device *dw9714_dev, u16 val)
64 {
65 	struct i2c_client *client = v4l2_get_subdevdata(&dw9714_dev->sd);
66 
67 	dw9714_dev->current_val = val;
68 
69 	return dw9714_i2c_write(client, DW9714_VAL(val, DW9714_DEFAULT_S));
70 }
71 
72 static int dw9714_set_ctrl(struct v4l2_ctrl *ctrl)
73 {
74 	struct dw9714_device *dev_vcm = to_dw9714_vcm(ctrl);
75 
76 	if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE)
77 		return dw9714_t_focus_vcm(dev_vcm, ctrl->val);
78 
79 	return -EINVAL;
80 }
81 
82 static const struct v4l2_ctrl_ops dw9714_vcm_ctrl_ops = {
83 	.s_ctrl = dw9714_set_ctrl,
84 };
85 
86 static int dw9714_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
87 {
88 	int rval;
89 
90 	rval = pm_runtime_get_sync(sd->dev);
91 	if (rval < 0) {
92 		pm_runtime_put_noidle(sd->dev);
93 		return rval;
94 	}
95 
96 	return 0;
97 }
98 
99 static int dw9714_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
100 {
101 	pm_runtime_put(sd->dev);
102 
103 	return 0;
104 }
105 
106 static const struct v4l2_subdev_internal_ops dw9714_int_ops = {
107 	.open = dw9714_open,
108 	.close = dw9714_close,
109 };
110 
111 static const struct v4l2_subdev_ops dw9714_ops = { };
112 
113 static void dw9714_subdev_cleanup(struct dw9714_device *dw9714_dev)
114 {
115 	v4l2_async_unregister_subdev(&dw9714_dev->sd);
116 	v4l2_ctrl_handler_free(&dw9714_dev->ctrls_vcm);
117 	media_entity_cleanup(&dw9714_dev->sd.entity);
118 }
119 
120 static int dw9714_init_controls(struct dw9714_device *dev_vcm)
121 {
122 	struct v4l2_ctrl_handler *hdl = &dev_vcm->ctrls_vcm;
123 	const struct v4l2_ctrl_ops *ops = &dw9714_vcm_ctrl_ops;
124 
125 	v4l2_ctrl_handler_init(hdl, 1);
126 
127 	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE,
128 			  0, DW9714_MAX_FOCUS_POS, DW9714_FOCUS_STEPS, 0);
129 
130 	if (hdl->error)
131 		dev_err(dev_vcm->sd.dev, "%s fail error: 0x%x\n",
132 			__func__, hdl->error);
133 	dev_vcm->sd.ctrl_handler = hdl;
134 	return hdl->error;
135 }
136 
137 static int dw9714_probe(struct i2c_client *client)
138 {
139 	struct dw9714_device *dw9714_dev;
140 	int rval;
141 
142 	dw9714_dev = devm_kzalloc(&client->dev, sizeof(*dw9714_dev),
143 				  GFP_KERNEL);
144 	if (dw9714_dev == NULL)
145 		return -ENOMEM;
146 
147 	v4l2_i2c_subdev_init(&dw9714_dev->sd, client, &dw9714_ops);
148 	dw9714_dev->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
149 	dw9714_dev->sd.internal_ops = &dw9714_int_ops;
150 
151 	rval = dw9714_init_controls(dw9714_dev);
152 	if (rval)
153 		goto err_cleanup;
154 
155 	rval = media_entity_pads_init(&dw9714_dev->sd.entity, 0, NULL);
156 	if (rval < 0)
157 		goto err_cleanup;
158 
159 	dw9714_dev->sd.entity.function = MEDIA_ENT_F_LENS;
160 
161 	rval = v4l2_async_register_subdev(&dw9714_dev->sd);
162 	if (rval < 0)
163 		goto err_cleanup;
164 
165 	pm_runtime_set_active(&client->dev);
166 	pm_runtime_enable(&client->dev);
167 	pm_runtime_idle(&client->dev);
168 
169 	return 0;
170 
171 err_cleanup:
172 	v4l2_ctrl_handler_free(&dw9714_dev->ctrls_vcm);
173 	media_entity_cleanup(&dw9714_dev->sd.entity);
174 
175 	return rval;
176 }
177 
178 static int dw9714_remove(struct i2c_client *client)
179 {
180 	struct v4l2_subdev *sd = i2c_get_clientdata(client);
181 	struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
182 
183 	pm_runtime_disable(&client->dev);
184 	dw9714_subdev_cleanup(dw9714_dev);
185 
186 	return 0;
187 }
188 
189 /*
190  * This function sets the vcm position, so it consumes least current
191  * The lens position is gradually moved in units of DW9714_CTRL_STEPS,
192  * to make the movements smoothly.
193  */
194 static int __maybe_unused dw9714_vcm_suspend(struct device *dev)
195 {
196 	struct i2c_client *client = to_i2c_client(dev);
197 	struct v4l2_subdev *sd = i2c_get_clientdata(client);
198 	struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
199 	int ret, val;
200 
201 	for (val = dw9714_dev->current_val & ~(DW9714_CTRL_STEPS - 1);
202 	     val >= 0; val -= DW9714_CTRL_STEPS) {
203 		ret = dw9714_i2c_write(client,
204 				       DW9714_VAL(val, DW9714_DEFAULT_S));
205 		if (ret)
206 			dev_err_once(dev, "%s I2C failure: %d", __func__, ret);
207 		usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10);
208 	}
209 	return 0;
210 }
211 
212 /*
213  * This function sets the vcm position to the value set by the user
214  * through v4l2_ctrl_ops s_ctrl handler
215  * The lens position is gradually moved in units of DW9714_CTRL_STEPS,
216  * to make the movements smoothly.
217  */
218 static int  __maybe_unused dw9714_vcm_resume(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 	for (val = dw9714_dev->current_val % DW9714_CTRL_STEPS;
226 	     val < dw9714_dev->current_val + DW9714_CTRL_STEPS - 1;
227 	     val += DW9714_CTRL_STEPS) {
228 		ret = dw9714_i2c_write(client,
229 				       DW9714_VAL(val, DW9714_DEFAULT_S));
230 		if (ret)
231 			dev_err_ratelimited(dev, "%s I2C failure: %d",
232 						__func__, ret);
233 		usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10);
234 	}
235 
236 	return 0;
237 }
238 
239 static const struct i2c_device_id dw9714_id_table[] = {
240 	{ DW9714_NAME, 0 },
241 	{ { 0 } }
242 };
243 MODULE_DEVICE_TABLE(i2c, dw9714_id_table);
244 
245 static const struct of_device_id dw9714_of_table[] = {
246 	{ .compatible = "dongwoon,dw9714" },
247 	{ { 0 } }
248 };
249 MODULE_DEVICE_TABLE(of, dw9714_of_table);
250 
251 static const struct dev_pm_ops dw9714_pm_ops = {
252 	SET_SYSTEM_SLEEP_PM_OPS(dw9714_vcm_suspend, dw9714_vcm_resume)
253 	SET_RUNTIME_PM_OPS(dw9714_vcm_suspend, dw9714_vcm_resume, NULL)
254 };
255 
256 static struct i2c_driver dw9714_i2c_driver = {
257 	.driver = {
258 		.name = DW9714_NAME,
259 		.pm = &dw9714_pm_ops,
260 		.of_match_table = dw9714_of_table,
261 	},
262 	.probe_new = dw9714_probe,
263 	.remove = dw9714_remove,
264 	.id_table = dw9714_id_table,
265 };
266 
267 module_i2c_driver(dw9714_i2c_driver);
268 
269 MODULE_AUTHOR("Tianshu Qiu <tian.shu.qiu@intel.com>");
270 MODULE_AUTHOR("Jian Xu Zheng <jian.xu.zheng@intel.com>");
271 MODULE_AUTHOR("Yuning Pu <yuning.pu@intel.com>");
272 MODULE_AUTHOR("Jouni Ukkonen <jouni.ukkonen@intel.com>");
273 MODULE_AUTHOR("Tommi Franttila <tommi.franttila@intel.com>");
274 MODULE_DESCRIPTION("DW9714 VCM driver");
275 MODULE_LICENSE("GPL v2");
276