drivers/media/i2c/dw9807-vcm.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 // Copyright (C) 2018 Intel Corporation
   3
   4 #include <linux/acpi.h>
   5 #include <linux/delay.h>
   6 #include <linux/i2c.h>
   7 #include <linux/iopoll.h>
   8 #include <linux/module.h>
   9 #include <linux/pm_runtime.h>
  10 #include <media/v4l2-ctrls.h>
  11 #include <media/v4l2-device.h>
  12
  13 #define DW9807_MAX_FOCUS_POS    1023
  14 /*
  15  * This sets the minimum granularity for the focus positions.
  16  * A value of 1 gives maximum accuracy for a desired focus position.
  17  */
  18 #define DW9807_FOCUS_STEPS      1
  19 /*
  20  * This acts as the minimum granularity of lens movement.
  21  * Keep this value power of 2, so the control steps can be
  22  * uniformly adjusted for gradual lens movement, with desired
  23  * number of control steps.
  24  */
  25 #define DW9807_CTRL_STEPS       16
  26 #define DW9807_CTRL_DELAY_US    1000
  27
  28 #define DW9807_CTL_ADDR         0x02
  29 /*
  30  * DW9807 separates two registers to control the VCM position.
  31  * One for MSB value, another is LSB value.
  32  */
  33 #define DW9807_MSB_ADDR         0x03
  34 #define DW9807_LSB_ADDR         0x04
  35 #define DW9807_STATUS_ADDR      0x05
  36 #define DW9807_MODE_ADDR        0x06
  37 #define DW9807_RESONANCE_ADDR   0x07
  38
  39 #define MAX_RETRY               10
  40
  41 struct dw9807_device {
  42         struct v4l2_ctrl_handler ctrls_vcm;
  43         struct v4l2_subdev sd;
  44         u16 current_val;
  45 };
  46
  47 static inline struct dw9807_device *sd_to_dw9807_vcm(
  48                                         struct v4l2_subdev *subdev)
  49 {
  50         return container_of(subdev, struct dw9807_device, sd);
  51 }
  52
  53 static int dw9807_i2c_check(struct i2c_client *client)
  54 {
  55         const char status_addr = DW9807_STATUS_ADDR;
  56         char status_result;
  57         int ret;
  58
  59         ret = i2c_master_send(client, &status_addr, sizeof(status_addr));
  60         if (ret < 0) {
  61                 dev_err(&client->dev, "I2C write STATUS address fail ret = %d\n",
  62                         ret);
  63                 return ret;
  64         }
  65
  66         ret = i2c_master_recv(client, &status_result, sizeof(status_result));
  67         if (ret < 0) {
  68                 dev_err(&client->dev, "I2C read STATUS value fail ret = %d\n",
  69                         ret);
  70                 return ret;
  71         }
  72
  73         return status_result;
  74 }
  75
  76 static int dw9807_set_dac(struct i2c_client *client, u16 data)
  77 {
  78         const char tx_data[3] = {
  79                 DW9807_MSB_ADDR, ((data >> 8) & 0x03), (data & 0xff)
  80         };
  81         int val, ret;
  82
  83         /*
  84          * According to the datasheet, need to check the bus status before we
  85          * write VCM position. This ensure that we really write the value
  86          * into the register
  87          */
  88         ret = readx_poll_timeout(dw9807_i2c_check, client, val, val <= 0,
  89                         DW9807_CTRL_DELAY_US, MAX_RETRY * DW9807_CTRL_DELAY_US);
  90
  91         if (ret || val < 0) {
  92                 if (ret) {
  93                         dev_warn(&client->dev,
  94                                 "Cannot do the write operation because VCM is busy\n");
  95                 }
  96
  97                 return ret ? -EBUSY : val;
  98         }
  99
 100         /* Write VCM position to registers */
 101         ret = i2c_master_send(client, tx_data, sizeof(tx_data));
 102         if (ret < 0) {
 103                 dev_err(&client->dev,
 104                         "I2C write MSB fail ret=%d\n", ret);
 105
 106                 return ret;
 107         }
 108
 109         return 0;
 110 }
 111
 112 static int dw9807_set_ctrl(struct v4l2_ctrl *ctrl)
 113 {
 114         struct dw9807_device *dev_vcm = container_of(ctrl->handler,
 115                 struct dw9807_device, ctrls_vcm);
 116
 117         if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE) {
 118                 struct i2c_client *client = v4l2_get_subdevdata(&dev_vcm->sd);
 119
 120                 dev_vcm->current_val = ctrl->val;
 121                 return dw9807_set_dac(client, ctrl->val);
 122         }
 123
 124         return -EINVAL;
 125 }
 126
 127 static const struct v4l2_ctrl_ops dw9807_vcm_ctrl_ops = {
 128         .s_ctrl = dw9807_set_ctrl,
 129 };
 130
 131 static int dw9807_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
 132 {
 133         return pm_runtime_resume_and_get(sd->dev);
 134 }
 135
 136 static int dw9807_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
 137 {
 138         pm_runtime_put(sd->dev);
 139
 140         return 0;
 141 }
 142
 143 static const struct v4l2_subdev_internal_ops dw9807_int_ops = {
 144         .open = dw9807_open,
 145         .close = dw9807_close,
 146 };
 147
 148 static const struct v4l2_subdev_ops dw9807_ops = { };
 149
 150 static void dw9807_subdev_cleanup(struct dw9807_device *dw9807_dev)
 151 {
 152         v4l2_async_unregister_subdev(&dw9807_dev->sd);
 153         v4l2_ctrl_handler_free(&dw9807_dev->ctrls_vcm);
 154         media_entity_cleanup(&dw9807_dev->sd.entity);
 155 }
 156
 157 static int dw9807_init_controls(struct dw9807_device *dev_vcm)
 158 {
 159         struct v4l2_ctrl_handler *hdl = &dev_vcm->ctrls_vcm;
 160         const struct v4l2_ctrl_ops *ops = &dw9807_vcm_ctrl_ops;
 161         struct i2c_client *client = v4l2_get_subdevdata(&dev_vcm->sd);
 162
 163         v4l2_ctrl_handler_init(hdl, 1);
 164
 165         v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE,
 166                           0, DW9807_MAX_FOCUS_POS, DW9807_FOCUS_STEPS, 0);
 167
 168         dev_vcm->sd.ctrl_handler = hdl;
 169         if (hdl->error) {
 170                 dev_err(&client->dev, "%s fail error: 0x%x\n",
 171                         __func__, hdl->error);
 172                 return hdl->error;
 173         }
 174
 175         return 0;
 176 }
 177
 178 static int dw9807_probe(struct i2c_client *client)
 179 {
 180         struct dw9807_device *dw9807_dev;
 181         int rval;
 182
 183         dw9807_dev = devm_kzalloc(&client->dev, sizeof(*dw9807_dev),
 184                                   GFP_KERNEL);
 185         if (dw9807_dev == NULL)
 186                 return -ENOMEM;
 187
 188         v4l2_i2c_subdev_init(&dw9807_dev->sd, client, &dw9807_ops);
 189         dw9807_dev->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
 190         dw9807_dev->sd.internal_ops = &dw9807_int_ops;
 191
 192         rval = dw9807_init_controls(dw9807_dev);
 193         if (rval)
 194                 goto err_cleanup;
 195
 196         rval = media_entity_pads_init(&dw9807_dev->sd.entity, 0, NULL);
 197         if (rval < 0)
 198                 goto err_cleanup;
 199
 200         dw9807_dev->sd.entity.function = MEDIA_ENT_F_LENS;
 201
 202         rval = v4l2_async_register_subdev(&dw9807_dev->sd);
 203         if (rval < 0)
 204                 goto err_cleanup;
 205
 206         pm_runtime_set_active(&client->dev);
 207         pm_runtime_enable(&client->dev);
 208         pm_runtime_idle(&client->dev);
 209
 210         return 0;
 211
 212 err_cleanup:
 213         v4l2_ctrl_handler_free(&dw9807_dev->ctrls_vcm);
 214         media_entity_cleanup(&dw9807_dev->sd.entity);
 215
 216         return rval;
 217 }
 218
 219 static void dw9807_remove(struct i2c_client *client)
 220 {
 221         struct v4l2_subdev *sd = i2c_get_clientdata(client);
 222         struct dw9807_device *dw9807_dev = sd_to_dw9807_vcm(sd);
 223
 224         pm_runtime_disable(&client->dev);
 225
 226         dw9807_subdev_cleanup(dw9807_dev);
 227 }
 228
 229 /*
 230  * This function sets the vcm position, so it consumes least current
 231  * The lens position is gradually moved in units of DW9807_CTRL_STEPS,
 232  * to make the movements smoothly.
 233  */
 234 static int __maybe_unused dw9807_vcm_suspend(struct device *dev)
 235 {
 236         struct i2c_client *client = to_i2c_client(dev);
 237         struct v4l2_subdev *sd = i2c_get_clientdata(client);
 238         struct dw9807_device *dw9807_dev = sd_to_dw9807_vcm(sd);
 239         const char tx_data[2] = { DW9807_CTL_ADDR, 0x01 };
 240         int ret, val;
 241
 242         for (val = dw9807_dev->current_val & ~(DW9807_CTRL_STEPS - 1);
 243              val >= 0; val -= DW9807_CTRL_STEPS) {
 244                 ret = dw9807_set_dac(client, val);
 245                 if (ret)
 246                         dev_err_once(dev, "%s I2C failure: %d", __func__, ret);
 247                 usleep_range(DW9807_CTRL_DELAY_US, DW9807_CTRL_DELAY_US + 10);
 248         }
 249
 250         /* Power down */
 251         ret = i2c_master_send(client, tx_data, sizeof(tx_data));
 252         if (ret < 0) {
 253                 dev_err(&client->dev, "I2C write CTL fail ret = %d\n", ret);
 254                 return ret;
 255         }
 256
 257         return 0;
 258 }
 259
 260 /*
 261  * This function sets the vcm position to the value set by the user
 262  * through v4l2_ctrl_ops s_ctrl handler
 263  * The lens position is gradually moved in units of DW9807_CTRL_STEPS,
 264  * to make the movements smoothly.
 265  */
 266 static int  __maybe_unused dw9807_vcm_resume(struct device *dev)
 267 {
 268         struct i2c_client *client = to_i2c_client(dev);
 269         struct v4l2_subdev *sd = i2c_get_clientdata(client);
 270         struct dw9807_device *dw9807_dev = sd_to_dw9807_vcm(sd);
 271         const char tx_data[2] = { DW9807_CTL_ADDR, 0x00 };
 272         int ret, val;
 273
 274         /* Power on */
 275         ret = i2c_master_send(client, tx_data, sizeof(tx_data));
 276         if (ret < 0) {
 277                 dev_err(&client->dev, "I2C write CTL fail ret = %d\n", ret);
 278                 return ret;
 279         }
 280
 281         for (val = dw9807_dev->current_val % DW9807_CTRL_STEPS;
 282              val < dw9807_dev->current_val + DW9807_CTRL_STEPS - 1;
 283              val += DW9807_CTRL_STEPS) {
 284                 ret = dw9807_set_dac(client, val);
 285                 if (ret)
 286                         dev_err_ratelimited(dev, "%s I2C failure: %d",
 287                                                 __func__, ret);
 288                 usleep_range(DW9807_CTRL_DELAY_US, DW9807_CTRL_DELAY_US + 10);
 289         }
 290
 291         return 0;
 292 }
 293
 294 static const struct of_device_id dw9807_of_table[] = {
 295         { .compatible = "dongwoon,dw9807-vcm" },
 296         /* Compatibility for older firmware, NEVER USE THIS IN FIRMWARE! */
 297         { .compatible = "dongwoon,dw9807" },
 298         { /* sentinel */ }
 299 };
 300 MODULE_DEVICE_TABLE(of, dw9807_of_table);
 301
 302 static const struct dev_pm_ops dw9807_pm_ops = {
 303         SET_SYSTEM_SLEEP_PM_OPS(dw9807_vcm_suspend, dw9807_vcm_resume)
 304         SET_RUNTIME_PM_OPS(dw9807_vcm_suspend, dw9807_vcm_resume, NULL)
 305 };
 306
 307 static struct i2c_driver dw9807_i2c_driver = {
 308         .driver = {
 309                 .name = "dw9807",
 310                 .pm = &dw9807_pm_ops,
 311                 .of_match_table = dw9807_of_table,
 312         },
 313         .probe = dw9807_probe,
 314         .remove = dw9807_remove,
 315 };
 316
 317 module_i2c_driver(dw9807_i2c_driver);
 318
 319 MODULE_AUTHOR("Chiang, Alan");
 320 MODULE_DESCRIPTION("DW9807 VCM driver");
 321 MODULE_LICENSE("GPL v2");