drivers/media/i2c/dw9714.c

   1 /*
   2  * Copyright (c) 2015--2017 Intel Corporation.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License version
   6  * 2 as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  */
  13
  14 #include <linux/delay.h>
  15 #include <linux/i2c.h>
  16 #include <linux/module.h>
  17 #include <linux/pm_runtime.h>
  18 #include <media/v4l2-ctrls.h>
  19 #include <media/v4l2-device.h>
  20
  21 #define DW9714_NAME             "dw9714"
  22 #define DW9714_MAX_FOCUS_POS    1023
  23 /*
  24  * This sets the minimum granularity for the focus positions.
  25  * A value of 1 gives maximum accuracy for a desired focus position
  26  */
  27 #define DW9714_FOCUS_STEPS      1
  28 /*
  29  * This acts as the minimum granularity of lens movement.
  30  * Keep this value power of 2, so the control steps can be
  31  * uniformly adjusted for gradual lens movement, with desired
  32  * number of control steps.
  33  */
  34 #define DW9714_CTRL_STEPS       16
  35 #define DW9714_CTRL_DELAY_US    1000
  36 /*
  37  * S[3:2] = 0x00, codes per step for "Linear Slope Control"
  38  * S[1:0] = 0x00, step period
  39  */
  40 #define DW9714_DEFAULT_S 0x0
  41 #define DW9714_VAL(data, s) ((data) << 4 | (s))
  42
  43 /* dw9714 device structure */
  44 struct dw9714_device {
  45         struct v4l2_ctrl_handler ctrls_vcm;
  46         struct v4l2_subdev sd;
  47         u16 current_val;
  48 };
  49
  50 static inline struct dw9714_device *to_dw9714_vcm(struct v4l2_ctrl *ctrl)
  51 {
  52         return container_of(ctrl->handler, struct dw9714_device, ctrls_vcm);
  53 }
  54
  55 static inline struct dw9714_device *sd_to_dw9714_vcm(struct v4l2_subdev *subdev)
  56 {
  57         return container_of(subdev, struct dw9714_device, sd);
  58 }
  59
  60 static int dw9714_i2c_write(struct i2c_client *client, u16 data)
  61 {
  62         int ret;
  63         __be16 val = cpu_to_be16(data);
  64
  65         ret = i2c_master_send(client, (const char *)&val, sizeof(val));
  66         if (ret != sizeof(val)) {
  67                 dev_err(&client->dev, "I2C write fail\n");
  68                 return -EIO;
  69         }
  70         return 0;
  71 }
  72
  73 static int dw9714_t_focus_vcm(struct dw9714_device *dw9714_dev, u16 val)
  74 {
  75         struct i2c_client *client = v4l2_get_subdevdata(&dw9714_dev->sd);
  76
  77         dw9714_dev->current_val = val;
  78
  79         return dw9714_i2c_write(client, DW9714_VAL(val, DW9714_DEFAULT_S));
  80 }
  81
  82 static int dw9714_set_ctrl(struct v4l2_ctrl *ctrl)
  83 {
  84         struct dw9714_device *dev_vcm = to_dw9714_vcm(ctrl);
  85
  86         if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE)
  87                 return dw9714_t_focus_vcm(dev_vcm, ctrl->val);
  88
  89         return -EINVAL;
  90 }
  91
  92 static const struct v4l2_ctrl_ops dw9714_vcm_ctrl_ops = {
  93         .s_ctrl = dw9714_set_ctrl,
  94 };
  95
  96 static int dw9714_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
  97 {
  98         int rval;
  99
 100         rval = pm_runtime_get_sync(sd->dev);
 101         if (rval < 0) {
 102                 pm_runtime_put_noidle(sd->dev);
 103                 return rval;
 104         }
 105
 106         return 0;
 107 }
 108
 109 static int dw9714_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
 110 {
 111         pm_runtime_put(sd->dev);
 112
 113         return 0;
 114 }
 115
 116 static const struct v4l2_subdev_internal_ops dw9714_int_ops = {
 117         .open = dw9714_open,
 118         .close = dw9714_close,
 119 };
 120
 121 static const struct v4l2_subdev_ops dw9714_ops = { };
 122
 123 static void dw9714_subdev_cleanup(struct dw9714_device *dw9714_dev)
 124 {
 125         v4l2_async_unregister_subdev(&dw9714_dev->sd);
 126         v4l2_ctrl_handler_free(&dw9714_dev->ctrls_vcm);
 127         media_entity_cleanup(&dw9714_dev->sd.entity);
 128 }
 129
 130 static int dw9714_init_controls(struct dw9714_device *dev_vcm)
 131 {
 132         struct v4l2_ctrl_handler *hdl = &dev_vcm->ctrls_vcm;
 133         const struct v4l2_ctrl_ops *ops = &dw9714_vcm_ctrl_ops;
 134
 135         v4l2_ctrl_handler_init(hdl, 1);
 136
 137         v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE,
 138                           0, DW9714_MAX_FOCUS_POS, DW9714_FOCUS_STEPS, 0);
 139
 140         if (hdl->error)
 141                 dev_err(dev_vcm->sd.dev, "%s fail error: 0x%x\n",
 142                         __func__, hdl->error);
 143         dev_vcm->sd.ctrl_handler = hdl;
 144         return hdl->error;
 145 }
 146
 147 static int dw9714_probe(struct i2c_client *client)
 148 {
 149         struct dw9714_device *dw9714_dev;
 150         int rval;
 151
 152         dw9714_dev = devm_kzalloc(&client->dev, sizeof(*dw9714_dev),
 153                                   GFP_KERNEL);
 154         if (dw9714_dev == NULL)
 155                 return -ENOMEM;
 156
 157         v4l2_i2c_subdev_init(&dw9714_dev->sd, client, &dw9714_ops);
 158         dw9714_dev->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
 159         dw9714_dev->sd.internal_ops = &dw9714_int_ops;
 160
 161         rval = dw9714_init_controls(dw9714_dev);
 162         if (rval)
 163                 goto err_cleanup;
 164
 165         rval = media_entity_pads_init(&dw9714_dev->sd.entity, 0, NULL);
 166         if (rval < 0)
 167                 goto err_cleanup;
 168
 169         dw9714_dev->sd.entity.function = MEDIA_ENT_F_LENS;
 170
 171         rval = v4l2_async_register_subdev(&dw9714_dev->sd);
 172         if (rval < 0)
 173                 goto err_cleanup;
 174
 175         pm_runtime_set_active(&client->dev);
 176         pm_runtime_enable(&client->dev);
 177         pm_runtime_idle(&client->dev);
 178
 179         return 0;
 180
 181 err_cleanup:
 182         dw9714_subdev_cleanup(dw9714_dev);
 183         dev_err(&client->dev, "Probe failed: %d\n", rval);
 184         return rval;
 185 }
 186
 187 static int dw9714_remove(struct i2c_client *client)
 188 {
 189         struct v4l2_subdev *sd = i2c_get_clientdata(client);
 190         struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
 191
 192         pm_runtime_disable(&client->dev);
 193         dw9714_subdev_cleanup(dw9714_dev);
 194
 195         return 0;
 196 }
 197
 198 /*
 199  * This function sets the vcm position, so it consumes least current
 200  * The lens position is gradually moved in units of DW9714_CTRL_STEPS,
 201  * to make the movements smoothly.
 202  */
 203 static int __maybe_unused dw9714_vcm_suspend(struct device *dev)
 204 {
 205         struct i2c_client *client = to_i2c_client(dev);
 206         struct v4l2_subdev *sd = i2c_get_clientdata(client);
 207         struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
 208         int ret, val;
 209
 210         for (val = dw9714_dev->current_val & ~(DW9714_CTRL_STEPS - 1);
 211              val >= 0; val -= DW9714_CTRL_STEPS) {
 212                 ret = dw9714_i2c_write(client,
 213                                        DW9714_VAL(val, DW9714_DEFAULT_S));
 214                 if (ret)
 215                         dev_err_once(dev, "%s I2C failure: %d", __func__, ret);
 216                 usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10);
 217         }
 218         return 0;
 219 }
 220
 221 /*
 222  * This function sets the vcm position to the value set by the user
 223  * through v4l2_ctrl_ops s_ctrl handler
 224  * The lens position is gradually moved in units of DW9714_CTRL_STEPS,
 225  * to make the movements smoothly.
 226  */
 227 static int  __maybe_unused dw9714_vcm_resume(struct device *dev)
 228 {
 229         struct i2c_client *client = to_i2c_client(dev);
 230         struct v4l2_subdev *sd = i2c_get_clientdata(client);
 231         struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
 232         int ret, val;
 233
 234         for (val = dw9714_dev->current_val % DW9714_CTRL_STEPS;
 235              val < dw9714_dev->current_val + DW9714_CTRL_STEPS - 1;
 236              val += DW9714_CTRL_STEPS) {
 237                 ret = dw9714_i2c_write(client,
 238                                        DW9714_VAL(val, DW9714_DEFAULT_S));
 239                 if (ret)
 240                         dev_err_ratelimited(dev, "%s I2C failure: %d",
 241                                                 __func__, ret);
 242                 usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10);
 243         }
 244
 245         return 0;
 246 }
 247
 248 static const struct i2c_device_id dw9714_id_table[] = {
 249         { DW9714_NAME, 0 },
 250         { { 0 } }
 251 };
 252 MODULE_DEVICE_TABLE(i2c, dw9714_id_table);
 253
 254 static const struct of_device_id dw9714_of_table[] = {
 255         { .compatible = "dongwoon,dw9714" },
 256         { { 0 } }
 257 };
 258 MODULE_DEVICE_TABLE(of, dw9714_of_table);
 259
 260 static const struct dev_pm_ops dw9714_pm_ops = {
 261         SET_SYSTEM_SLEEP_PM_OPS(dw9714_vcm_suspend, dw9714_vcm_resume)
 262         SET_RUNTIME_PM_OPS(dw9714_vcm_suspend, dw9714_vcm_resume, NULL)
 263 };
 264
 265 static struct i2c_driver dw9714_i2c_driver = {
 266         .driver = {
 267                 .name = DW9714_NAME,
 268                 .pm = &dw9714_pm_ops,
 269                 .of_match_table = dw9714_of_table,
 270         },
 271         .probe_new = dw9714_probe,
 272         .remove = dw9714_remove,
 273         .id_table = dw9714_id_table,
 274 };
 275
 276 module_i2c_driver(dw9714_i2c_driver);
 277
 278 MODULE_AUTHOR("Tianshu Qiu <tian.shu.qiu@intel.com>");
 279 MODULE_AUTHOR("Jian Xu Zheng <jian.xu.zheng@intel.com>");
 280 MODULE_AUTHOR("Yuning Pu <yuning.pu@intel.com>");
 281 MODULE_AUTHOR("Jouni Ukkonen <jouni.ukkonen@intel.com>");
 282 MODULE_AUTHOR("Tommi Franttila <tommi.franttila@intel.com>");
 283 MODULE_DESCRIPTION("DW9714 VCM driver");
 284 MODULE_LICENSE("GPL v2");