drivers/media/i2c/ak7375.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/module.h>
   8 #include <linux/pm_runtime.h>
   9 #include <linux/regulator/consumer.h>
  10 #include <media/v4l2-ctrls.h>
  11 #include <media/v4l2-device.h>
  12
  13 struct ak73xx_chipdef {
  14         u8 reg_position;
  15         u8 reg_cont;
  16         u8 shift_pos;
  17         u8 mode_active;
  18         u8 mode_standby;
  19         bool has_standby;       /* Some chips may not have standby mode */
  20         u16 focus_pos_max;
  21         /*
  22          * This sets the minimum granularity for the focus positions.
  23          * A value of 1 gives maximum accuracy for a desired focus position
  24          */
  25         u16 focus_steps;
  26         /*
  27          * This acts as the minimum granularity of lens movement.
  28          * Keep this value power of 2, so the control steps can be
  29          * uniformly adjusted for gradual lens movement, with desired
  30          * number of control steps.
  31          */
  32         u16 ctrl_steps;
  33         u16 ctrl_delay_us;
  34         /*
  35          * The vcm may take time (tDELAY) to power on and start taking
  36          * I2C messages.
  37          */
  38         u16 power_delay_us;
  39 };
  40
  41 static const struct ak73xx_chipdef ak7345_cdef = {
  42         .reg_position   = 0x0,
  43         .reg_cont       = 0x2,
  44         .shift_pos      = 7,    /* 9 bits position values, need to << 7 */
  45         .mode_active    = 0x0,
  46         .has_standby    = false,
  47         .focus_pos_max  = 511,
  48         .focus_steps    = 1,
  49         .ctrl_steps     = 16,
  50         .ctrl_delay_us  = 1000,
  51         .power_delay_us = 20000,
  52 };
  53
  54 static const struct ak73xx_chipdef ak7375_cdef = {
  55         .reg_position   = 0x0,
  56         .reg_cont       = 0x2,
  57         .shift_pos      = 4,    /* 12 bits position values, need to << 4 */
  58         .mode_active    = 0x0,
  59         .mode_standby   = 0x40,
  60         .has_standby    = true,
  61         .focus_pos_max  = 4095,
  62         .focus_steps    = 1,
  63         .ctrl_steps     = 64,
  64         .ctrl_delay_us  = 1000,
  65         .power_delay_us = 10000,
  66 };
  67
  68 static const char * const ak7375_supply_names[] = {
  69         "vdd",
  70         "vio",
  71 };
  72
  73 /* ak7375 device structure */
  74 struct ak7375_device {
  75         const struct ak73xx_chipdef *cdef;
  76         struct v4l2_ctrl_handler ctrls_vcm;
  77         struct v4l2_subdev sd;
  78         struct v4l2_ctrl *focus;
  79         struct regulator_bulk_data supplies[ARRAY_SIZE(ak7375_supply_names)];
  80
  81         /* active or standby mode */
  82         bool active;
  83 };
  84
  85 static inline struct ak7375_device *to_ak7375_vcm(struct v4l2_ctrl *ctrl)
  86 {
  87         return container_of(ctrl->handler, struct ak7375_device, ctrls_vcm);
  88 }
  89
  90 static inline struct ak7375_device *sd_to_ak7375_vcm(struct v4l2_subdev *subdev)
  91 {
  92         return container_of(subdev, struct ak7375_device, sd);
  93 }
  94
  95 static int ak7375_i2c_write(struct ak7375_device *ak7375,
  96         u8 addr, u16 data, u8 size)
  97 {
  98         struct i2c_client *client = v4l2_get_subdevdata(&ak7375->sd);
  99         u8 buf[3];
 100         int ret;
 101
 102         if (size != 1 && size != 2)
 103                 return -EINVAL;
 104         buf[0] = addr;
 105         buf[size] = data & 0xff;
 106         if (size == 2)
 107                 buf[1] = (data >> 8) & 0xff;
 108         ret = i2c_master_send(client, (const char *)buf, size + 1);
 109         if (ret < 0)
 110                 return ret;
 111         if (ret != size + 1)
 112                 return -EIO;
 113
 114         return 0;
 115 }
 116
 117 static int ak7375_set_ctrl(struct v4l2_ctrl *ctrl)
 118 {
 119         struct ak7375_device *dev_vcm = to_ak7375_vcm(ctrl);
 120         const struct ak73xx_chipdef *cdef = dev_vcm->cdef;
 121
 122         if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE)
 123                 return ak7375_i2c_write(dev_vcm, cdef->reg_position,
 124                                         ctrl->val << cdef->shift_pos, 2);
 125
 126         return -EINVAL;
 127 }
 128
 129 static const struct v4l2_ctrl_ops ak7375_vcm_ctrl_ops = {
 130         .s_ctrl = ak7375_set_ctrl,
 131 };
 132
 133 static int ak7375_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
 134 {
 135         return pm_runtime_resume_and_get(sd->dev);
 136 }
 137
 138 static int ak7375_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
 139 {
 140         pm_runtime_put(sd->dev);
 141
 142         return 0;
 143 }
 144
 145 static const struct v4l2_subdev_internal_ops ak7375_int_ops = {
 146         .open = ak7375_open,
 147         .close = ak7375_close,
 148 };
 149
 150 static const struct v4l2_subdev_ops ak7375_ops = { };
 151
 152 static void ak7375_subdev_cleanup(struct ak7375_device *ak7375_dev)
 153 {
 154         v4l2_async_unregister_subdev(&ak7375_dev->sd);
 155         v4l2_ctrl_handler_free(&ak7375_dev->ctrls_vcm);
 156         media_entity_cleanup(&ak7375_dev->sd.entity);
 157 }
 158
 159 static int ak7375_init_controls(struct ak7375_device *dev_vcm)
 160 {
 161         struct v4l2_ctrl_handler *hdl = &dev_vcm->ctrls_vcm;
 162         const struct v4l2_ctrl_ops *ops = &ak7375_vcm_ctrl_ops;
 163         const struct ak73xx_chipdef *cdef = dev_vcm->cdef;
 164
 165         v4l2_ctrl_handler_init(hdl, 1);
 166
 167         dev_vcm->focus = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE,
 168                 0, cdef->focus_pos_max, cdef->focus_steps, 0);
 169
 170         if (hdl->error)
 171                 dev_err(dev_vcm->sd.dev, "%s fail error: 0x%x\n",
 172                         __func__, hdl->error);
 173         dev_vcm->sd.ctrl_handler = hdl;
 174
 175         return hdl->error;
 176 }
 177
 178 static int ak7375_probe(struct i2c_client *client)
 179 {
 180         struct ak7375_device *ak7375_dev;
 181         int ret;
 182         unsigned int i;
 183
 184         ak7375_dev = devm_kzalloc(&client->dev, sizeof(*ak7375_dev),
 185                                   GFP_KERNEL);
 186         if (!ak7375_dev)
 187                 return -ENOMEM;
 188
 189         ak7375_dev->cdef = device_get_match_data(&client->dev);
 190
 191         for (i = 0; i < ARRAY_SIZE(ak7375_supply_names); i++)
 192                 ak7375_dev->supplies[i].supply = ak7375_supply_names[i];
 193
 194         ret = devm_regulator_bulk_get(&client->dev,
 195                                       ARRAY_SIZE(ak7375_supply_names),
 196                                       ak7375_dev->supplies);
 197         if (ret) {
 198                 dev_err_probe(&client->dev, ret, "Failed to get regulators\n");
 199                 return ret;
 200         }
 201
 202         v4l2_i2c_subdev_init(&ak7375_dev->sd, client, &ak7375_ops);
 203         ak7375_dev->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
 204         ak7375_dev->sd.internal_ops = &ak7375_int_ops;
 205         ak7375_dev->sd.entity.function = MEDIA_ENT_F_LENS;
 206
 207         ret = ak7375_init_controls(ak7375_dev);
 208         if (ret)
 209                 goto err_cleanup;
 210
 211         ret = media_entity_pads_init(&ak7375_dev->sd.entity, 0, NULL);
 212         if (ret < 0)
 213                 goto err_cleanup;
 214
 215         ret = v4l2_async_register_subdev(&ak7375_dev->sd);
 216         if (ret < 0)
 217                 goto err_cleanup;
 218
 219         pm_runtime_set_active(&client->dev);
 220         pm_runtime_enable(&client->dev);
 221         pm_runtime_idle(&client->dev);
 222
 223         return 0;
 224
 225 err_cleanup:
 226         v4l2_ctrl_handler_free(&ak7375_dev->ctrls_vcm);
 227         media_entity_cleanup(&ak7375_dev->sd.entity);
 228
 229         return ret;
 230 }
 231
 232 static void ak7375_remove(struct i2c_client *client)
 233 {
 234         struct v4l2_subdev *sd = i2c_get_clientdata(client);
 235         struct ak7375_device *ak7375_dev = sd_to_ak7375_vcm(sd);
 236
 237         ak7375_subdev_cleanup(ak7375_dev);
 238         pm_runtime_disable(&client->dev);
 239         pm_runtime_set_suspended(&client->dev);
 240 }
 241
 242 /*
 243  * This function sets the vcm position, so it consumes least current
 244  * The lens position is gradually moved in units of ctrl_steps,
 245  * to make the movements smoothly.
 246  */
 247 static int __maybe_unused ak7375_vcm_suspend(struct device *dev)
 248 {
 249         struct v4l2_subdev *sd = dev_get_drvdata(dev);
 250         struct ak7375_device *ak7375_dev = sd_to_ak7375_vcm(sd);
 251         const struct ak73xx_chipdef *cdef = ak7375_dev->cdef;
 252         int ret, val;
 253
 254         if (!ak7375_dev->active)
 255                 return 0;
 256
 257         for (val = ak7375_dev->focus->val & ~(cdef->ctrl_steps - 1);
 258              val >= 0; val -= cdef->ctrl_steps) {
 259                 ret = ak7375_i2c_write(ak7375_dev, cdef->reg_position,
 260                                        val << cdef->shift_pos, 2);
 261                 if (ret)
 262                         dev_err_once(dev, "%s I2C failure: %d\n",
 263                                      __func__, ret);
 264                 usleep_range(cdef->ctrl_delay_us, cdef->ctrl_delay_us + 10);
 265         }
 266
 267         if (cdef->has_standby) {
 268                 ret = ak7375_i2c_write(ak7375_dev, cdef->reg_cont,
 269                                        cdef->mode_standby, 1);
 270                 if (ret)
 271                         dev_err(dev, "%s I2C failure: %d\n", __func__, ret);
 272         }
 273
 274         ret = regulator_bulk_disable(ARRAY_SIZE(ak7375_supply_names),
 275                                      ak7375_dev->supplies);
 276         if (ret)
 277                 return ret;
 278
 279         ak7375_dev->active = false;
 280
 281         return 0;
 282 }
 283
 284 /*
 285  * This function sets the vcm position to the value set by the user
 286  * through v4l2_ctrl_ops s_ctrl handler
 287  * The lens position is gradually moved in units of ctrl_steps,
 288  * to make the movements smoothly.
 289  */
 290 static int __maybe_unused ak7375_vcm_resume(struct device *dev)
 291 {
 292         struct v4l2_subdev *sd = dev_get_drvdata(dev);
 293         struct ak7375_device *ak7375_dev = sd_to_ak7375_vcm(sd);
 294         const struct ak73xx_chipdef *cdef = ak7375_dev->cdef;
 295         int ret, val;
 296
 297         if (ak7375_dev->active)
 298                 return 0;
 299
 300         ret = regulator_bulk_enable(ARRAY_SIZE(ak7375_supply_names),
 301                                     ak7375_dev->supplies);
 302         if (ret)
 303                 return ret;
 304
 305         /* Wait for vcm to become ready */
 306         usleep_range(cdef->power_delay_us, cdef->power_delay_us + 500);
 307
 308         ret = ak7375_i2c_write(ak7375_dev, cdef->reg_cont,
 309                                cdef->mode_active, 1);
 310         if (ret) {
 311                 dev_err(dev, "%s I2C failure: %d\n", __func__, ret);
 312                 return ret;
 313         }
 314
 315         for (val = ak7375_dev->focus->val % cdef->ctrl_steps;
 316              val <= ak7375_dev->focus->val;
 317              val += cdef->ctrl_steps) {
 318                 ret = ak7375_i2c_write(ak7375_dev, cdef->reg_position,
 319                                        val << cdef->shift_pos, 2);
 320                 if (ret)
 321                         dev_err_ratelimited(dev, "%s I2C failure: %d\n",
 322                                                 __func__, ret);
 323                 usleep_range(cdef->ctrl_delay_us, cdef->ctrl_delay_us + 10);
 324         }
 325
 326         ak7375_dev->active = true;
 327
 328         return 0;
 329 }
 330
 331 static const struct of_device_id ak7375_of_table[] = {
 332         { .compatible = "asahi-kasei,ak7345", .data = &ak7345_cdef, },
 333         { .compatible = "asahi-kasei,ak7375", .data = &ak7375_cdef, },
 334         { /* sentinel */ }
 335 };
 336 MODULE_DEVICE_TABLE(of, ak7375_of_table);
 337
 338 static const struct dev_pm_ops ak7375_pm_ops = {
 339         SET_SYSTEM_SLEEP_PM_OPS(ak7375_vcm_suspend, ak7375_vcm_resume)
 340         SET_RUNTIME_PM_OPS(ak7375_vcm_suspend, ak7375_vcm_resume, NULL)
 341 };
 342
 343 static struct i2c_driver ak7375_i2c_driver = {
 344         .driver = {
 345                 .name = "ak7375",
 346                 .pm = &ak7375_pm_ops,
 347                 .of_match_table = ak7375_of_table,
 348         },
 349         .probe = ak7375_probe,
 350         .remove = ak7375_remove,
 351 };
 352 module_i2c_driver(ak7375_i2c_driver);
 353
 354 MODULE_AUTHOR("Tianshu Qiu <tian.shu.qiu@intel.com>");
 355 MODULE_AUTHOR("Bingbu Cao <bingbu.cao@intel.com>");
 356 MODULE_DESCRIPTION("AK7375 VCM driver");
 357 MODULE_LICENSE("GPL v2");