xref: /openbmc/linux/drivers/media/i2c/dw9714.c (revision f3d7c2cd)
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 	return pm_runtime_resume_and_get(sd->dev);
89 }
90 
91 static int dw9714_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
92 {
93 	pm_runtime_put(sd->dev);
94 
95 	return 0;
96 }
97 
98 static const struct v4l2_subdev_internal_ops dw9714_int_ops = {
99 	.open = dw9714_open,
100 	.close = dw9714_close,
101 };
102 
103 static const struct v4l2_subdev_ops dw9714_ops = { };
104 
105 static void dw9714_subdev_cleanup(struct dw9714_device *dw9714_dev)
106 {
107 	v4l2_async_unregister_subdev(&dw9714_dev->sd);
108 	v4l2_ctrl_handler_free(&dw9714_dev->ctrls_vcm);
109 	media_entity_cleanup(&dw9714_dev->sd.entity);
110 }
111 
112 static int dw9714_init_controls(struct dw9714_device *dev_vcm)
113 {
114 	struct v4l2_ctrl_handler *hdl = &dev_vcm->ctrls_vcm;
115 	const struct v4l2_ctrl_ops *ops = &dw9714_vcm_ctrl_ops;
116 
117 	v4l2_ctrl_handler_init(hdl, 1);
118 
119 	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE,
120 			  0, DW9714_MAX_FOCUS_POS, DW9714_FOCUS_STEPS, 0);
121 
122 	if (hdl->error)
123 		dev_err(dev_vcm->sd.dev, "%s fail error: 0x%x\n",
124 			__func__, hdl->error);
125 	dev_vcm->sd.ctrl_handler = hdl;
126 	return hdl->error;
127 }
128 
129 static int dw9714_probe(struct i2c_client *client)
130 {
131 	struct dw9714_device *dw9714_dev;
132 	int rval;
133 
134 	dw9714_dev = devm_kzalloc(&client->dev, sizeof(*dw9714_dev),
135 				  GFP_KERNEL);
136 	if (dw9714_dev == NULL)
137 		return -ENOMEM;
138 
139 	v4l2_i2c_subdev_init(&dw9714_dev->sd, client, &dw9714_ops);
140 	dw9714_dev->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
141 	dw9714_dev->sd.internal_ops = &dw9714_int_ops;
142 
143 	rval = dw9714_init_controls(dw9714_dev);
144 	if (rval)
145 		goto err_cleanup;
146 
147 	rval = media_entity_pads_init(&dw9714_dev->sd.entity, 0, NULL);
148 	if (rval < 0)
149 		goto err_cleanup;
150 
151 	dw9714_dev->sd.entity.function = MEDIA_ENT_F_LENS;
152 
153 	rval = v4l2_async_register_subdev(&dw9714_dev->sd);
154 	if (rval < 0)
155 		goto err_cleanup;
156 
157 	pm_runtime_set_active(&client->dev);
158 	pm_runtime_enable(&client->dev);
159 	pm_runtime_idle(&client->dev);
160 
161 	return 0;
162 
163 err_cleanup:
164 	v4l2_ctrl_handler_free(&dw9714_dev->ctrls_vcm);
165 	media_entity_cleanup(&dw9714_dev->sd.entity);
166 
167 	return rval;
168 }
169 
170 static int dw9714_remove(struct i2c_client *client)
171 {
172 	struct v4l2_subdev *sd = i2c_get_clientdata(client);
173 	struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
174 
175 	pm_runtime_disable(&client->dev);
176 	dw9714_subdev_cleanup(dw9714_dev);
177 
178 	return 0;
179 }
180 
181 /*
182  * This function sets the vcm position, so it consumes least current
183  * The lens position is gradually moved in units of DW9714_CTRL_STEPS,
184  * to make the movements smoothly.
185  */
186 static int __maybe_unused dw9714_vcm_suspend(struct device *dev)
187 {
188 	struct i2c_client *client = to_i2c_client(dev);
189 	struct v4l2_subdev *sd = i2c_get_clientdata(client);
190 	struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
191 	int ret, val;
192 
193 	for (val = dw9714_dev->current_val & ~(DW9714_CTRL_STEPS - 1);
194 	     val >= 0; val -= DW9714_CTRL_STEPS) {
195 		ret = dw9714_i2c_write(client,
196 				       DW9714_VAL(val, DW9714_DEFAULT_S));
197 		if (ret)
198 			dev_err_once(dev, "%s I2C failure: %d", __func__, ret);
199 		usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10);
200 	}
201 	return 0;
202 }
203 
204 /*
205  * This function sets the vcm position to the value set by the user
206  * through v4l2_ctrl_ops s_ctrl handler
207  * The lens position is gradually moved in units of DW9714_CTRL_STEPS,
208  * to make the movements smoothly.
209  */
210 static int  __maybe_unused dw9714_vcm_resume(struct device *dev)
211 {
212 	struct i2c_client *client = to_i2c_client(dev);
213 	struct v4l2_subdev *sd = i2c_get_clientdata(client);
214 	struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
215 	int ret, val;
216 
217 	for (val = dw9714_dev->current_val % DW9714_CTRL_STEPS;
218 	     val < dw9714_dev->current_val + DW9714_CTRL_STEPS - 1;
219 	     val += DW9714_CTRL_STEPS) {
220 		ret = dw9714_i2c_write(client,
221 				       DW9714_VAL(val, DW9714_DEFAULT_S));
222 		if (ret)
223 			dev_err_ratelimited(dev, "%s I2C failure: %d",
224 						__func__, ret);
225 		usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10);
226 	}
227 
228 	return 0;
229 }
230 
231 static const struct i2c_device_id dw9714_id_table[] = {
232 	{ DW9714_NAME, 0 },
233 	{ { 0 } }
234 };
235 MODULE_DEVICE_TABLE(i2c, dw9714_id_table);
236 
237 static const struct of_device_id dw9714_of_table[] = {
238 	{ .compatible = "dongwoon,dw9714" },
239 	{ { 0 } }
240 };
241 MODULE_DEVICE_TABLE(of, dw9714_of_table);
242 
243 static const struct dev_pm_ops dw9714_pm_ops = {
244 	SET_SYSTEM_SLEEP_PM_OPS(dw9714_vcm_suspend, dw9714_vcm_resume)
245 	SET_RUNTIME_PM_OPS(dw9714_vcm_suspend, dw9714_vcm_resume, NULL)
246 };
247 
248 static struct i2c_driver dw9714_i2c_driver = {
249 	.driver = {
250 		.name = DW9714_NAME,
251 		.pm = &dw9714_pm_ops,
252 		.of_match_table = dw9714_of_table,
253 	},
254 	.probe_new = dw9714_probe,
255 	.remove = dw9714_remove,
256 	.id_table = dw9714_id_table,
257 };
258 
259 module_i2c_driver(dw9714_i2c_driver);
260 
261 MODULE_AUTHOR("Tianshu Qiu <tian.shu.qiu@intel.com>");
262 MODULE_AUTHOR("Jian Xu Zheng");
263 MODULE_AUTHOR("Yuning Pu <yuning.pu@intel.com>");
264 MODULE_AUTHOR("Jouni Ukkonen <jouni.ukkonen@intel.com>");
265 MODULE_AUTHOR("Tommi Franttila <tommi.franttila@intel.com>");
266 MODULE_DESCRIPTION("DW9714 VCM driver");
267 MODULE_LICENSE("GPL v2");
268