media/i2c/dw9714.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 // Copyright (c) 2015--2017 Intel Corporation.
0003
0004 #include <linux/delay.h>
0005 #include <linux/i2c.h>
0006 #include <linux/module.h>
0007 #include <linux/pm_runtime.h>
0008 #include <linux/regulator/consumer.h>
0009 #include <media/v4l2-ctrls.h>
0010 #include <media/v4l2-device.h>
0011 #include <media/v4l2-event.h>
0012
0013 #define DW9714_NAME     "dw9714"
0014 #define DW9714_MAX_FOCUS_POS    1023
0015 /*
0016  * This sets the minimum granularity for the focus positions.
0017  * A value of 1 gives maximum accuracy for a desired focus position
0018  */
0019 #define DW9714_FOCUS_STEPS  1
0020 /*
0021  * This acts as the minimum granularity of lens movement.
0022  * Keep this value power of 2, so the control steps can be
0023  * uniformly adjusted for gradual lens movement, with desired
0024  * number of control steps.
0025  */
0026 #define DW9714_CTRL_STEPS   16
0027 #define DW9714_CTRL_DELAY_US    1000
0028 /*
0029  * S[3:2] = 0x00, codes per step for "Linear Slope Control"
0030  * S[1:0] = 0x00, step period
0031  */
0032 #define DW9714_DEFAULT_S 0x0
0033 #define DW9714_VAL(data, s) ((data) << 4 | (s))
0034
0035 /* dw9714 device structure */
0036 struct dw9714_device {
0037     struct v4l2_ctrl_handler ctrls_vcm;
0038     struct v4l2_subdev sd;
0039     u16 current_val;
0040     struct regulator *vcc;
0041 };
0042
0043 static inline struct dw9714_device *to_dw9714_vcm(struct v4l2_ctrl *ctrl)
0044 {
0045     return container_of(ctrl->handler, struct dw9714_device, ctrls_vcm);
0046 }
0047
0048 static inline struct dw9714_device *sd_to_dw9714_vcm(struct v4l2_subdev *subdev)
0049 {
0050     return container_of(subdev, struct dw9714_device, sd);
0051 }
0052
0053 static int dw9714_i2c_write(struct i2c_client *client, u16 data)
0054 {
0055     int ret;
0056     __be16 val = cpu_to_be16(data);
0057
0058     ret = i2c_master_send(client, (const char *)&val, sizeof(val));
0059     if (ret != sizeof(val)) {
0060         dev_err(&client->dev, "I2C write fail\n");
0061         return -EIO;
0062     }
0063     return 0;
0064 }
0065
0066 static int dw9714_t_focus_vcm(struct dw9714_device *dw9714_dev, u16 val)
0067 {
0068     struct i2c_client *client = v4l2_get_subdevdata(&dw9714_dev->sd);
0069
0070     dw9714_dev->current_val = val;
0071
0072     return dw9714_i2c_write(client, DW9714_VAL(val, DW9714_DEFAULT_S));
0073 }
0074
0075 static int dw9714_set_ctrl(struct v4l2_ctrl *ctrl)
0076 {
0077     struct dw9714_device *dev_vcm = to_dw9714_vcm(ctrl);
0078
0079     if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE)
0080         return dw9714_t_focus_vcm(dev_vcm, ctrl->val);
0081
0082     return -EINVAL;
0083 }
0084
0085 static const struct v4l2_ctrl_ops dw9714_vcm_ctrl_ops = {
0086     .s_ctrl = dw9714_set_ctrl,
0087 };
0088
0089 static int dw9714_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
0090 {
0091     return pm_runtime_resume_and_get(sd->dev);
0092 }
0093
0094 static int dw9714_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
0095 {
0096     pm_runtime_put(sd->dev);
0097
0098     return 0;
0099 }
0100
0101 static const struct v4l2_subdev_internal_ops dw9714_int_ops = {
0102     .open = dw9714_open,
0103     .close = dw9714_close,
0104 };
0105
0106 static const struct v4l2_subdev_core_ops dw9714_core_ops = {
0107     .log_status = v4l2_ctrl_subdev_log_status,
0108     .subscribe_event = v4l2_ctrl_subdev_subscribe_event,
0109     .unsubscribe_event = v4l2_event_subdev_unsubscribe,
0110 };
0111
0112 static const struct v4l2_subdev_ops dw9714_ops = {
0113     .core = &dw9714_core_ops,
0114 };
0115
0116 static void dw9714_subdev_cleanup(struct dw9714_device *dw9714_dev)
0117 {
0118     v4l2_async_unregister_subdev(&dw9714_dev->sd);
0119     v4l2_ctrl_handler_free(&dw9714_dev->ctrls_vcm);
0120     media_entity_cleanup(&dw9714_dev->sd.entity);
0121 }
0122
0123 static int dw9714_init_controls(struct dw9714_device *dev_vcm)
0124 {
0125     struct v4l2_ctrl_handler *hdl = &dev_vcm->ctrls_vcm;
0126     const struct v4l2_ctrl_ops *ops = &dw9714_vcm_ctrl_ops;
0127
0128     v4l2_ctrl_handler_init(hdl, 1);
0129
0130     v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE,
0131               0, DW9714_MAX_FOCUS_POS, DW9714_FOCUS_STEPS, 0);
0132
0133     if (hdl->error)
0134         dev_err(dev_vcm->sd.dev, "%s fail error: 0x%x\n",
0135             __func__, hdl->error);
0136     dev_vcm->sd.ctrl_handler = hdl;
0137     return hdl->error;
0138 }
0139
0140 static int dw9714_probe(struct i2c_client *client)
0141 {
0142     struct dw9714_device *dw9714_dev;
0143     int rval;
0144
0145     dw9714_dev = devm_kzalloc(&client->dev, sizeof(*dw9714_dev),
0146                   GFP_KERNEL);
0147     if (dw9714_dev == NULL)
0148         return -ENOMEM;
0149
0150     dw9714_dev->vcc = devm_regulator_get(&client->dev, "vcc");
0151     if (IS_ERR(dw9714_dev->vcc))
0152         return PTR_ERR(dw9714_dev->vcc);
0153
0154     rval = regulator_enable(dw9714_dev->vcc);
0155     if (rval < 0) {
0156         dev_err(&client->dev, "failed to enable vcc: %d\n", rval);
0157         return rval;
0158     }
0159
0160     v4l2_i2c_subdev_init(&dw9714_dev->sd, client, &dw9714_ops);
0161     dw9714_dev->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
0162                 V4L2_SUBDEV_FL_HAS_EVENTS;
0163     dw9714_dev->sd.internal_ops = &dw9714_int_ops;
0164
0165     rval = dw9714_init_controls(dw9714_dev);
0166     if (rval)
0167         goto err_cleanup;
0168
0169     rval = media_entity_pads_init(&dw9714_dev->sd.entity, 0, NULL);
0170     if (rval < 0)
0171         goto err_cleanup;
0172
0173     dw9714_dev->sd.entity.function = MEDIA_ENT_F_LENS;
0174
0175     rval = v4l2_async_register_subdev(&dw9714_dev->sd);
0176     if (rval < 0)
0177         goto err_cleanup;
0178
0179     pm_runtime_set_active(&client->dev);
0180     pm_runtime_enable(&client->dev);
0181     pm_runtime_idle(&client->dev);
0182
0183     return 0;
0184
0185 err_cleanup:
0186     regulator_disable(dw9714_dev->vcc);
0187     v4l2_ctrl_handler_free(&dw9714_dev->ctrls_vcm);
0188     media_entity_cleanup(&dw9714_dev->sd.entity);
0189
0190     return rval;
0191 }
0192
0193 static int dw9714_remove(struct i2c_client *client)
0194 {
0195     struct v4l2_subdev *sd = i2c_get_clientdata(client);
0196     struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
0197     int ret;
0198
0199     pm_runtime_disable(&client->dev);
0200     if (!pm_runtime_status_suspended(&client->dev)) {
0201         ret = regulator_disable(dw9714_dev->vcc);
0202         if (ret) {
0203             dev_err(&client->dev,
0204                 "Failed to disable vcc: %d\n", ret);
0205         }
0206     }
0207     pm_runtime_set_suspended(&client->dev);
0208     dw9714_subdev_cleanup(dw9714_dev);
0209
0210     return 0;
0211 }
0212
0213 /*
0214  * This function sets the vcm position, so it consumes least current
0215  * The lens position is gradually moved in units of DW9714_CTRL_STEPS,
0216  * to make the movements smoothly.
0217  */
0218 static int __maybe_unused dw9714_vcm_suspend(struct device *dev)
0219 {
0220     struct i2c_client *client = to_i2c_client(dev);
0221     struct v4l2_subdev *sd = i2c_get_clientdata(client);
0222     struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
0223     int ret, val;
0224
0225     if (pm_runtime_suspended(&client->dev))
0226         return 0;
0227
0228     for (val = dw9714_dev->current_val & ~(DW9714_CTRL_STEPS - 1);
0229          val >= 0; val -= DW9714_CTRL_STEPS) {
0230         ret = dw9714_i2c_write(client,
0231                        DW9714_VAL(val, DW9714_DEFAULT_S));
0232         if (ret)
0233             dev_err_once(dev, "%s I2C failure: %d", __func__, ret);
0234         usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10);
0235     }
0236
0237     ret = regulator_disable(dw9714_dev->vcc);
0238     if (ret)
0239         dev_err(dev, "Failed to disable vcc: %d\n", ret);
0240
0241     return ret;
0242 }
0243
0244 /*
0245  * This function sets the vcm position to the value set by the user
0246  * through v4l2_ctrl_ops s_ctrl handler
0247  * The lens position is gradually moved in units of DW9714_CTRL_STEPS,
0248  * to make the movements smoothly.
0249  */
0250 static int  __maybe_unused dw9714_vcm_resume(struct device *dev)
0251 {
0252     struct i2c_client *client = to_i2c_client(dev);
0253     struct v4l2_subdev *sd = i2c_get_clientdata(client);
0254     struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
0255     int ret, val;
0256
0257     if (pm_runtime_suspended(&client->dev))
0258         return 0;
0259
0260     ret = regulator_enable(dw9714_dev->vcc);
0261     if (ret) {
0262         dev_err(dev, "Failed to enable vcc: %d\n", ret);
0263         return ret;
0264     }
0265     usleep_range(1000, 2000);
0266
0267     for (val = dw9714_dev->current_val % DW9714_CTRL_STEPS;
0268          val < dw9714_dev->current_val + DW9714_CTRL_STEPS - 1;
0269          val += DW9714_CTRL_STEPS) {
0270         ret = dw9714_i2c_write(client,
0271                        DW9714_VAL(val, DW9714_DEFAULT_S));
0272         if (ret)
0273             dev_err_ratelimited(dev, "%s I2C failure: %d",
0274                         __func__, ret);
0275         usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10);
0276     }
0277
0278     return 0;
0279 }
0280
0281 static const struct i2c_device_id dw9714_id_table[] = {
0282     { DW9714_NAME, 0 },
0283     { { 0 } }
0284 };
0285 MODULE_DEVICE_TABLE(i2c, dw9714_id_table);
0286
0287 static const struct of_device_id dw9714_of_table[] = {
0288     { .compatible = "dongwoon,dw9714" },
0289     { { 0 } }
0290 };
0291 MODULE_DEVICE_TABLE(of, dw9714_of_table);
0292
0293 static const struct dev_pm_ops dw9714_pm_ops = {
0294     SET_SYSTEM_SLEEP_PM_OPS(dw9714_vcm_suspend, dw9714_vcm_resume)
0295     SET_RUNTIME_PM_OPS(dw9714_vcm_suspend, dw9714_vcm_resume, NULL)
0296 };
0297
0298 static struct i2c_driver dw9714_i2c_driver = {
0299     .driver = {
0300         .name = DW9714_NAME,
0301         .pm = &dw9714_pm_ops,
0302         .of_match_table = dw9714_of_table,
0303     },
0304     .probe_new = dw9714_probe,
0305     .remove = dw9714_remove,
0306     .id_table = dw9714_id_table,
0307 };
0308
0309 module_i2c_driver(dw9714_i2c_driver);
0310
0311 MODULE_AUTHOR("Tianshu Qiu <tian.shu.qiu@intel.com>");
0312 MODULE_AUTHOR("Jian Xu Zheng");
0313 MODULE_AUTHOR("Yuning Pu <yuning.pu@intel.com>");
0314 MODULE_AUTHOR("Jouni Ukkonen <jouni.ukkonen@intel.com>");
0315 MODULE_AUTHOR("Tommi Franttila <tommi.franttila@intel.com>");
0316 MODULE_DESCRIPTION("DW9714 VCM driver");
0317 MODULE_LICENSE("GPL v2");