drivers/iio/proximity/vl53l0x-i2c.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Support for ST VL53L0X FlightSense ToF Ranging Sensor on a i2c bus.
   4  *
   5  * Copyright (C) 2016 STMicroelectronics Imaging Division.
   6  * Copyright (C) 2018 Song Qiang <[email protected]>
   7  * Copyright (C) 2020 Ivan Drobyshevskyi <[email protected]>
   8  *
   9  * Datasheet available at
  10  * <https://www.st.com/resource/en/datasheet/vl53l0x.pdf>
  11  *
  12  * Default 7-bit i2c slave address 0x29.
  13  *
  14  * TODO: FIFO buffer, continuous mode, range selection, sensor ID check.
  15  */
  16
  17 #include <linux/delay.h>
  18 #include <linux/i2c.h>
  19 #include <linux/interrupt.h>
  20 #include <linux/module.h>
  21
  22 #include <linux/iio/iio.h>
  23
  24 #define VL_REG_SYSRANGE_START                           0x00
  25
  26 #define VL_REG_SYSRANGE_MODE_MASK                       GENMASK(3, 0)
  27 #define VL_REG_SYSRANGE_MODE_SINGLESHOT                 0x00
  28 #define VL_REG_SYSRANGE_MODE_START_STOP                 BIT(0)
  29 #define VL_REG_SYSRANGE_MODE_BACKTOBACK                 BIT(1)
  30 #define VL_REG_SYSRANGE_MODE_TIMED                      BIT(2)
  31 #define VL_REG_SYSRANGE_MODE_HISTOGRAM                  BIT(3)
  32
  33 #define VL_REG_SYSTEM_INTERRUPT_CONFIG_GPIO             0x0A
  34 #define VL_REG_SYSTEM_INTERRUPT_GPIO_NEW_SAMPLE_READY   BIT(2)
  35
  36 #define VL_REG_SYSTEM_INTERRUPT_CLEAR                   0x0B
  37
  38 #define VL_REG_RESULT_INT_STATUS                        0x13
  39 #define VL_REG_RESULT_RANGE_STATUS                      0x14
  40 #define VL_REG_RESULT_RANGE_STATUS_COMPLETE             BIT(0)
  41
  42 struct vl53l0x_data {
  43         struct i2c_client *client;
  44         struct completion completion;
  45 };
  46
  47 static irqreturn_t vl53l0x_handle_irq(int irq, void *priv)
  48 {
  49         struct iio_dev *indio_dev = priv;
  50         struct vl53l0x_data *data = iio_priv(indio_dev);
  51
  52         complete(&data->completion);
  53
  54         return IRQ_HANDLED;
  55 }
  56
  57 static int vl53l0x_configure_irq(struct i2c_client *client,
  58                                  struct iio_dev *indio_dev)
  59 {
  60         struct vl53l0x_data *data = iio_priv(indio_dev);
  61         int ret;
  62
  63         ret = devm_request_irq(&client->dev, client->irq, vl53l0x_handle_irq,
  64                         IRQF_TRIGGER_FALLING, indio_dev->name, indio_dev);
  65         if (ret) {
  66                 dev_err(&client->dev, "devm_request_irq error: %d\n", ret);
  67                 return ret;
  68         }
  69
  70         ret = i2c_smbus_write_byte_data(data->client,
  71                         VL_REG_SYSTEM_INTERRUPT_CONFIG_GPIO,
  72                         VL_REG_SYSTEM_INTERRUPT_GPIO_NEW_SAMPLE_READY);
  73         if (ret < 0)
  74                 dev_err(&client->dev, "failed to configure IRQ: %d\n", ret);
  75
  76         return ret;
  77 }
  78
  79 static void vl53l0x_clear_irq(struct vl53l0x_data *data)
  80 {
  81         struct device *dev = &data->client->dev;
  82         int ret;
  83
  84         ret = i2c_smbus_write_byte_data(data->client,
  85                                         VL_REG_SYSTEM_INTERRUPT_CLEAR, 1);
  86         if (ret < 0)
  87                 dev_err(dev, "failed to clear error irq: %d\n", ret);
  88
  89         ret = i2c_smbus_write_byte_data(data->client,
  90                                         VL_REG_SYSTEM_INTERRUPT_CLEAR, 0);
  91         if (ret < 0)
  92                 dev_err(dev, "failed to clear range irq: %d\n", ret);
  93
  94         ret = i2c_smbus_read_byte_data(data->client, VL_REG_RESULT_INT_STATUS);
  95         if (ret < 0 || ret & 0x07)
  96                 dev_err(dev, "failed to clear irq: %d\n", ret);
  97 }
  98
  99 static int vl53l0x_read_proximity(struct vl53l0x_data *data,
 100                                   const struct iio_chan_spec *chan,
 101                                   int *val)
 102 {
 103         struct i2c_client *client = data->client;
 104         u16 tries = 20;
 105         u8 buffer[12];
 106         int ret;
 107
 108         ret = i2c_smbus_write_byte_data(client, VL_REG_SYSRANGE_START, 1);
 109         if (ret < 0)
 110                 return ret;
 111
 112         if (data->client->irq) {
 113                 reinit_completion(&data->completion);
 114
 115                 ret = wait_for_completion_timeout(&data->completion, HZ/10);
 116                 if (ret < 0)
 117                         return ret;
 118                 else if (ret == 0)
 119                         return -ETIMEDOUT;
 120
 121                 vl53l0x_clear_irq(data);
 122         } else {
 123                 do {
 124                         ret = i2c_smbus_read_byte_data(client,
 125                                                VL_REG_RESULT_RANGE_STATUS);
 126                         if (ret < 0)
 127                                 return ret;
 128
 129                         if (ret & VL_REG_RESULT_RANGE_STATUS_COMPLETE)
 130                                 break;
 131
 132                         usleep_range(1000, 5000);
 133                 } while (--tries);
 134                 if (!tries)
 135                         return -ETIMEDOUT;
 136         }
 137
 138         ret = i2c_smbus_read_i2c_block_data(client, VL_REG_RESULT_RANGE_STATUS,
 139                                             12, buffer);
 140         if (ret < 0)
 141                 return ret;
 142         else if (ret != 12)
 143                 return -EREMOTEIO;
 144
 145         /* Values should be between 30~1200 in millimeters. */
 146         *val = (buffer[10] << 8) + buffer[11];
 147
 148         return 0;
 149 }
 150
 151 static const struct iio_chan_spec vl53l0x_channels[] = {
 152         {
 153                 .type = IIO_DISTANCE,
 154                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 155                                       BIT(IIO_CHAN_INFO_SCALE),
 156         },
 157 };
 158
 159 static int vl53l0x_read_raw(struct iio_dev *indio_dev,
 160                             const struct iio_chan_spec *chan,
 161                             int *val, int *val2, long mask)
 162 {
 163         struct vl53l0x_data *data = iio_priv(indio_dev);
 164         int ret;
 165
 166         if (chan->type != IIO_DISTANCE)
 167                 return -EINVAL;
 168
 169         switch (mask) {
 170         case IIO_CHAN_INFO_RAW:
 171                 ret = vl53l0x_read_proximity(data, chan, val);
 172                 if (ret < 0)
 173                         return ret;
 174
 175                 return IIO_VAL_INT;
 176         case IIO_CHAN_INFO_SCALE:
 177                 *val = 0;
 178                 *val2 = 1000;
 179
 180                 return IIO_VAL_INT_PLUS_MICRO;
 181         default:
 182                 return -EINVAL;
 183         }
 184 }
 185
 186 static const struct iio_info vl53l0x_info = {
 187         .read_raw = vl53l0x_read_raw,
 188 };
 189
 190 static int vl53l0x_probe(struct i2c_client *client)
 191 {
 192         struct vl53l0x_data *data;
 193         struct iio_dev *indio_dev;
 194
 195         indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
 196         if (!indio_dev)
 197                 return -ENOMEM;
 198
 199         data = iio_priv(indio_dev);
 200         data->client = client;
 201         i2c_set_clientdata(client, indio_dev);
 202
 203         if (!i2c_check_functionality(client->adapter,
 204                                      I2C_FUNC_SMBUS_READ_I2C_BLOCK |
 205                                      I2C_FUNC_SMBUS_BYTE_DATA))
 206                 return -EOPNOTSUPP;
 207
 208         indio_dev->name = "vl53l0x";
 209         indio_dev->info = &vl53l0x_info;
 210         indio_dev->channels = vl53l0x_channels;
 211         indio_dev->num_channels = ARRAY_SIZE(vl53l0x_channels);
 212         indio_dev->modes = INDIO_DIRECT_MODE;
 213
 214         /* usage of interrupt is optional */
 215         if (client->irq) {
 216                 int ret;
 217
 218                 init_completion(&data->completion);
 219
 220                 ret = vl53l0x_configure_irq(client, indio_dev);
 221                 if (ret)
 222                         return ret;
 223         }
 224
 225         return devm_iio_device_register(&client->dev, indio_dev);
 226 }
 227
 228 static const struct of_device_id st_vl53l0x_dt_match[] = {
 229         { .compatible = "st,vl53l0x", },
 230         { }
 231 };
 232 MODULE_DEVICE_TABLE(of, st_vl53l0x_dt_match);
 233
 234 static struct i2c_driver vl53l0x_driver = {
 235         .driver = {
 236                 .name = "vl53l0x-i2c",
 237                 .of_match_table = st_vl53l0x_dt_match,
 238         },
 239         .probe_new = vl53l0x_probe,
 240 };
 241 module_i2c_driver(vl53l0x_driver);
 242
 243 MODULE_AUTHOR("Song Qiang <[email protected]>");
 244 MODULE_DESCRIPTION("ST vl53l0x ToF ranging sensor driver");
 245 MODULE_LICENSE("GPL v2");