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/acpi.h>
  15 #include <linux/delay.h>
  16 #include <linux/i2c.h>
  17 #include <linux/module.h>
  18 #include <linux/pm_runtime.h>
  19 #include <media/v4l2-ctrls.h>
  20 #include <media/v4l2-device.h>
  21
  22 #define DW9714_NAME             "dw9714"
  23 #define DW9714_MAX_FOCUS_POS    1023
  24 /*
  25  * This acts as the minimum granularity of lens movement.
  26  * Keep this value power of 2, so the control steps can be
  27  * uniformly adjusted for gradual lens movement, with desired
  28  * number of control steps.
  29  */
  30 #define DW9714_CTRL_STEPS       16
  31 #define DW9714_CTRL_DELAY_US    1000
  32 /*
  33  * S[3:2] = 0x00, codes per step for "Linear Slope Control"
  34  * S[1:0] = 0x00, step period
  35  */
  36 #define DW9714_DEFAULT_S 0x0
  37 #define DW9714_VAL(data, s) ((data) << 4 | (s))
  38
  39 /* dw9714 device structure */
  40 struct dw9714_device {
  41         struct i2c_client *client;
  42         struct v4l2_ctrl_handler ctrls_vcm;
  43         struct v4l2_subdev sd;
  44         u16 current_val;
  45 };
  46
  47 static inline struct dw9714_device *to_dw9714_vcm(struct v4l2_ctrl *ctrl)
  48 {
  49         return container_of(ctrl->handler, struct dw9714_device, ctrls_vcm);
  50 }
  51
  52 static inline struct dw9714_device *sd_to_dw9714_vcm(struct v4l2_subdev *subdev)
  53 {
  54         return container_of(subdev, struct dw9714_device, sd);
  55 }
  56
  57 static int dw9714_i2c_write(struct i2c_client *client, u16 data)
  58 {
  59         int ret;
  60         u16 val = cpu_to_be16(data);
  61
  62         ret = i2c_master_send(client, (const char *)&val, sizeof(val));
  63         if (ret != sizeof(val)) {
  64                 dev_err(&client->dev, "I2C write fail\n");
  65                 return -EIO;
  66         }
  67         return 0;
  68 }
  69
  70 static int dw9714_t_focus_vcm(struct dw9714_device *dw9714_dev, u16 val)
  71 {
  72         struct i2c_client *client = dw9714_dev->client;
  73
  74         dw9714_dev->current_val = val;
  75
  76         return dw9714_i2c_write(client, DW9714_VAL(val, DW9714_DEFAULT_S));
  77 }
  78
  79 static int dw9714_set_ctrl(struct v4l2_ctrl *ctrl)
  80 {
  81         struct dw9714_device *dev_vcm = to_dw9714_vcm(ctrl);
  82
  83         if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE)
  84                 return dw9714_t_focus_vcm(dev_vcm, ctrl->val);
  85
  86         return -EINVAL;
  87 }
  88
  89 static const struct v4l2_ctrl_ops dw9714_vcm_ctrl_ops = {
  90         .s_ctrl = dw9714_set_ctrl,
  91 };
  92
  93 static int dw9714_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
  94 {
  95         struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
  96         struct device *dev = &dw9714_dev->client->dev;
  97         int rval;
  98
  99         rval = pm_runtime_get_sync(dev);
 100         if (rval < 0) {
 101                 pm_runtime_put_noidle(dev);
 102                 return rval;
 103         }
 104
 105         return 0;
 106 }
 107
 108 static int dw9714_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
 109 {
 110         struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
 111         struct device *dev = &dw9714_dev->client->dev;
 112
 113         pm_runtime_put(dev);
 114
 115         return 0;
 116 }
 117
 118 static const struct v4l2_subdev_internal_ops dw9714_int_ops = {
 119         .open = dw9714_open,
 120         .close = dw9714_close,
 121 };
 122
 123 static const struct v4l2_subdev_ops dw9714_ops = { };
 124
 125 static void dw9714_subdev_cleanup(struct dw9714_device *dw9714_dev)
 126 {
 127         v4l2_async_unregister_subdev(&dw9714_dev->sd);
 128         v4l2_ctrl_handler_free(&dw9714_dev->ctrls_vcm);
 129         media_entity_cleanup(&dw9714_dev->sd.entity);
 130 }
 131
 132 static int dw9714_init_controls(struct dw9714_device *dev_vcm)
 133 {
 134         struct v4l2_ctrl_handler *hdl = &dev_vcm->ctrls_vcm;
 135         const struct v4l2_ctrl_ops *ops = &dw9714_vcm_ctrl_ops;
 136         struct i2c_client *client = dev_vcm->client;
 137
 138         v4l2_ctrl_handler_init(hdl, 1);
 139
 140         v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE,
 141                           0, DW9714_MAX_FOCUS_POS, DW9714_CTRL_STEPS, 0);
 142
 143         if (hdl->error)
 144                 dev_err(&client->dev, "%s fail error: 0x%x\n",
 145                         __func__, hdl->error);
 146         dev_vcm->sd.ctrl_handler = hdl;
 147         return hdl->error;
 148 }
 149
 150 static int dw9714_probe(struct i2c_client *client,
 151                         const struct i2c_device_id *devid)
 152 {
 153         struct dw9714_device *dw9714_dev;
 154         int rval;
 155
 156         dw9714_dev = devm_kzalloc(&client->dev, sizeof(*dw9714_dev),
 157                                   GFP_KERNEL);
 158         if (dw9714_dev == NULL)
 159                 return -ENOMEM;
 160
 161         dw9714_dev->client = client;
 162
 163         v4l2_i2c_subdev_init(&dw9714_dev->sd, client, &dw9714_ops);
 164         dw9714_dev->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
 165         dw9714_dev->sd.internal_ops = &dw9714_int_ops;
 166
 167         rval = dw9714_init_controls(dw9714_dev);
 168         if (rval)
 169                 goto err_cleanup;
 170
 171         rval = media_entity_pads_init(&dw9714_dev->sd.entity, 0, NULL);
 172         if (rval < 0)
 173                 goto err_cleanup;
 174
 175         dw9714_dev->sd.entity.function = MEDIA_ENT_F_LENS;
 176
 177         rval = v4l2_async_register_subdev(&dw9714_dev->sd);
 178         if (rval < 0)
 179                 goto err_cleanup;
 180
 181         pm_runtime_set_active(&client->dev);
 182         pm_runtime_enable(&client->dev);
 183
 184         return 0;
 185
 186 err_cleanup:
 187         dw9714_subdev_cleanup(dw9714_dev);
 188         dev_err(&client->dev, "Probe failed: %d\n", rval);
 189         return rval;
 190 }
 191
 192 static int dw9714_remove(struct i2c_client *client)
 193 {
 194         struct v4l2_subdev *sd = i2c_get_clientdata(client);
 195         struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
 196
 197         pm_runtime_disable(&client->dev);
 198         dw9714_subdev_cleanup(dw9714_dev);
 199
 200         return 0;
 201 }
 202
 203 /*
 204  * This function sets the vcm position, so it consumes least current
 205  * The lens position is gradually moved in units of DW9714_CTRL_STEPS,
 206  * to make the movements smoothly.
 207  */
 208 static int __maybe_unused dw9714_vcm_suspend(struct device *dev)
 209 {
 210         struct i2c_client *client = to_i2c_client(dev);
 211         struct v4l2_subdev *sd = i2c_get_clientdata(client);
 212         struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
 213         int ret, val;
 214
 215         for (val = dw9714_dev->current_val & ~(DW9714_CTRL_STEPS - 1);
 216              val >= 0; val -= DW9714_CTRL_STEPS) {
 217                 ret = dw9714_i2c_write(client,
 218                                        DW9714_VAL(val, DW9714_DEFAULT_S));
 219                 if (ret)
 220                         dev_err_once(dev, "%s I2C failure: %d", __func__, ret);
 221                 usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10);
 222         }
 223         return 0;
 224 }
 225
 226 /*
 227  * This function sets the vcm position to the value set by the user
 228  * through v4l2_ctrl_ops s_ctrl handler
 229  * The lens position is gradually moved in units of DW9714_CTRL_STEPS,
 230  * to make the movements smoothly.
 231  */
 232 static int  __maybe_unused dw9714_vcm_resume(struct device *dev)
 233 {
 234         struct i2c_client *client = to_i2c_client(dev);
 235         struct v4l2_subdev *sd = i2c_get_clientdata(client);
 236         struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
 237         int ret, val;
 238
 239         for (val = dw9714_dev->current_val % DW9714_CTRL_STEPS;
 240              val < dw9714_dev->current_val + DW9714_CTRL_STEPS - 1;
 241              val += DW9714_CTRL_STEPS) {
 242                 ret = dw9714_i2c_write(client,
 243                                        DW9714_VAL(val, DW9714_DEFAULT_S));
 244                 if (ret)
 245                         dev_err_ratelimited(dev, "%s I2C failure: %d",
 246                                                 __func__, ret);
 247                 usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10);
 248         }
 249
 250         return 0;
 251 }
 252
 253 #ifdef CONFIG_ACPI
 254 static const struct acpi_device_id dw9714_acpi_match[] = {
 255         {},
 256 };
 257 MODULE_DEVICE_TABLE(acpi, dw9714_acpi_match);
 258 #endif
 259
 260 static const struct i2c_device_id dw9714_id_table[] = {
 261         {DW9714_NAME, 0},
 262         {}
 263 };
 264
 265 MODULE_DEVICE_TABLE(i2c, dw9714_id_table);
 266
 267 static const struct dev_pm_ops dw9714_pm_ops = {
 268         SET_SYSTEM_SLEEP_PM_OPS(dw9714_vcm_suspend, dw9714_vcm_resume)
 269         SET_RUNTIME_PM_OPS(dw9714_vcm_suspend, dw9714_vcm_resume, NULL)
 270 };
 271
 272 static struct i2c_driver dw9714_i2c_driver = {
 273         .driver = {
 274                 .name = DW9714_NAME,
 275                 .pm = &dw9714_pm_ops,
 276                 .acpi_match_table = ACPI_PTR(dw9714_acpi_match),
 277         },
 278         .probe = dw9714_probe,
 279         .remove = dw9714_remove,
 280         .id_table = dw9714_id_table,
 281 };
 282
 283 module_i2c_driver(dw9714_i2c_driver);
 284
 285 MODULE_AUTHOR("Tianshu Qiu <tian.shu.qiu@intel.com>");
 286 MODULE_AUTHOR("Jian Xu Zheng <jian.xu.zheng@intel.com>");
 287 MODULE_AUTHOR("Yuning Pu <yuning.pu@intel.com>");
 288 MODULE_AUTHOR("Jouni Ukkonen <jouni.ukkonen@intel.com>");
 289 MODULE_AUTHOR("Tommi Franttila <tommi.franttila@intel.com>");
 290 MODULE_DESCRIPTION("DW9714 VCM driver");
 291 MODULE_LICENSE("GPL v2");