root/drivers/iio/gyro/itg3200_core.c

/* [<][>][^][v][top][bottom][index][help] */

DEFINITIONS

This source file includes following definitions.
  1. itg3200_write_reg_8
  2. itg3200_read_reg_8
  3. itg3200_read_reg_s16
  4. itg3200_read_raw
  5. itg3200_write_raw
  6. itg3200_reset
  7. itg3200_enable_full_scale
  8. itg3200_initial_setup
  9. itg3200_get_mount_matrix
  10. itg3200_probe
  11. itg3200_remove
  12. itg3200_suspend
  13. itg3200_resume

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * itg3200_core.c -- support InvenSense ITG3200
   4  *                   Digital 3-Axis Gyroscope driver
   5  *
   6  * Copyright (c) 2011 Christian Strobel <christian.strobel@iis.fraunhofer.de>
   7  * Copyright (c) 2011 Manuel Stahl <manuel.stahl@iis.fraunhofer.de>
   8  * Copyright (c) 2012 Thorsten Nowak <thorsten.nowak@iis.fraunhofer.de>
   9  *
  10  * TODO:
  11  * - Support digital low pass filter
  12  * - Support power management
  13  */
  14 
  15 #include <linux/interrupt.h>
  16 #include <linux/irq.h>
  17 #include <linux/i2c.h>
  18 #include <linux/gpio.h>
  19 #include <linux/slab.h>
  20 #include <linux/stat.h>
  21 #include <linux/module.h>
  22 #include <linux/delay.h>
  23 
  24 #include <linux/iio/iio.h>
  25 #include <linux/iio/sysfs.h>
  26 #include <linux/iio/events.h>
  27 #include <linux/iio/buffer.h>
  28 
  29 #include <linux/iio/gyro/itg3200.h>
  30 
  31 
  32 int itg3200_write_reg_8(struct iio_dev *indio_dev,
  33                 u8 reg_address, u8 val)
  34 {
  35         struct itg3200 *st = iio_priv(indio_dev);
  36 
  37         return i2c_smbus_write_byte_data(st->i2c, 0x80 | reg_address, val);
  38 }
  39 
  40 int itg3200_read_reg_8(struct iio_dev *indio_dev,
  41                 u8 reg_address, u8 *val)
  42 {
  43         struct itg3200 *st = iio_priv(indio_dev);
  44         int ret;
  45 
  46         ret = i2c_smbus_read_byte_data(st->i2c, reg_address);
  47         if (ret < 0)
  48                 return ret;
  49         *val = ret;
  50         return 0;
  51 }
  52 
  53 static int itg3200_read_reg_s16(struct iio_dev *indio_dev, u8 lower_reg_address,
  54                 int *val)
  55 {
  56         struct itg3200 *st = iio_priv(indio_dev);
  57         struct i2c_client *client = st->i2c;
  58         int ret;
  59         s16 out;
  60 
  61         struct i2c_msg msg[2] = {
  62                 {
  63                         .addr = client->addr,
  64                         .flags = client->flags,
  65                         .len = 1,
  66                         .buf = (char *)&lower_reg_address,
  67                 },
  68                 {
  69                         .addr = client->addr,
  70                         .flags = client->flags | I2C_M_RD,
  71                         .len = 2,
  72                         .buf = (char *)&out,
  73                 },
  74         };
  75 
  76         lower_reg_address |= 0x80;
  77         ret = i2c_transfer(client->adapter, msg, 2);
  78         be16_to_cpus(&out);
  79         *val = out;
  80 
  81         return (ret == 2) ? 0 : ret;
  82 }
  83 
  84 static int itg3200_read_raw(struct iio_dev *indio_dev,
  85                 const struct iio_chan_spec *chan,
  86                 int *val, int *val2, long info)
  87 {
  88         int ret = 0;
  89         u8 reg;
  90         u8 regval;
  91 
  92         switch (info) {
  93         case IIO_CHAN_INFO_RAW:
  94                 reg = (u8)chan->address;
  95                 ret = itg3200_read_reg_s16(indio_dev, reg, val);
  96                 return IIO_VAL_INT;
  97         case IIO_CHAN_INFO_SCALE:
  98                 *val = 0;
  99                 if (chan->type == IIO_TEMP)
 100                         *val2 = 1000000000/280;
 101                 else
 102                         *val2 = 1214142; /* (1 / 14,375) * (PI / 180) */
 103                 return IIO_VAL_INT_PLUS_NANO;
 104         case IIO_CHAN_INFO_OFFSET:
 105                 /* Only the temperature channel has an offset */
 106                 *val = 23000;
 107                 return IIO_VAL_INT;
 108         case IIO_CHAN_INFO_SAMP_FREQ:
 109                 ret = itg3200_read_reg_8(indio_dev, ITG3200_REG_DLPF, &regval);
 110                 if (ret)
 111                         return ret;
 112 
 113                 *val = (regval & ITG3200_DLPF_CFG_MASK) ? 1000 : 8000;
 114 
 115                 ret = itg3200_read_reg_8(indio_dev,
 116                                          ITG3200_REG_SAMPLE_RATE_DIV,
 117                                          &regval);
 118                 if (ret)
 119                         return ret;
 120 
 121                 *val /= regval + 1;
 122                 return IIO_VAL_INT;
 123 
 124         default:
 125                 return -EINVAL;
 126         }
 127 }
 128 
 129 static int itg3200_write_raw(struct iio_dev *indio_dev,
 130                              struct iio_chan_spec const *chan,
 131                              int val,
 132                              int val2,
 133                              long mask)
 134 {
 135         int ret;
 136         u8 t;
 137 
 138         switch (mask) {
 139         case IIO_CHAN_INFO_SAMP_FREQ:
 140                 if (val == 0 || val2 != 0)
 141                         return -EINVAL;
 142 
 143                 mutex_lock(&indio_dev->mlock);
 144 
 145                 ret = itg3200_read_reg_8(indio_dev, ITG3200_REG_DLPF, &t);
 146                 if (ret) {
 147                         mutex_unlock(&indio_dev->mlock);
 148                         return ret;
 149                 }
 150                 t = ((t & ITG3200_DLPF_CFG_MASK) ? 1000u : 8000u) / val - 1;
 151 
 152                 ret = itg3200_write_reg_8(indio_dev,
 153                                           ITG3200_REG_SAMPLE_RATE_DIV,
 154                                           t);
 155 
 156                 mutex_unlock(&indio_dev->mlock);
 157         return ret;
 158 
 159         default:
 160                 return -EINVAL;
 161         }
 162 }
 163 
 164 /*
 165  * Reset device and internal registers to the power-up-default settings
 166  * Use the gyro clock as reference, as suggested by the datasheet
 167  */
 168 static int itg3200_reset(struct iio_dev *indio_dev)
 169 {
 170         struct itg3200 *st = iio_priv(indio_dev);
 171         int ret;
 172 
 173         dev_dbg(&st->i2c->dev, "reset device");
 174 
 175         ret = itg3200_write_reg_8(indio_dev,
 176                         ITG3200_REG_POWER_MANAGEMENT,
 177                         ITG3200_RESET);
 178         if (ret) {
 179                 dev_err(&st->i2c->dev, "error resetting device");
 180                 goto error_ret;
 181         }
 182 
 183         /* Wait for PLL (1ms according to datasheet) */
 184         udelay(1500);
 185 
 186         ret = itg3200_write_reg_8(indio_dev,
 187                         ITG3200_REG_IRQ_CONFIG,
 188                         ITG3200_IRQ_ACTIVE_HIGH |
 189                         ITG3200_IRQ_PUSH_PULL |
 190                         ITG3200_IRQ_LATCH_50US_PULSE |
 191                         ITG3200_IRQ_LATCH_CLEAR_ANY);
 192 
 193         if (ret)
 194                 dev_err(&st->i2c->dev, "error init device");
 195 
 196 error_ret:
 197         return ret;
 198 }
 199 
 200 /* itg3200_enable_full_scale() - Disables the digital low pass filter */
 201 static int itg3200_enable_full_scale(struct iio_dev *indio_dev)
 202 {
 203         u8 val;
 204         int ret;
 205 
 206         ret = itg3200_read_reg_8(indio_dev, ITG3200_REG_DLPF, &val);
 207         if (ret)
 208                 goto err_ret;
 209 
 210         val |= ITG3200_DLPF_FS_SEL_2000;
 211         return itg3200_write_reg_8(indio_dev, ITG3200_REG_DLPF, val);
 212 
 213 err_ret:
 214         return ret;
 215 }
 216 
 217 static int itg3200_initial_setup(struct iio_dev *indio_dev)
 218 {
 219         struct itg3200 *st = iio_priv(indio_dev);
 220         int ret;
 221         u8 val;
 222 
 223         ret = itg3200_reset(indio_dev);
 224         if (ret)
 225                 goto err_ret;
 226 
 227         ret = itg3200_read_reg_8(indio_dev, ITG3200_REG_ADDRESS, &val);
 228         if (ret)
 229                 goto err_ret;
 230 
 231         if (((val >> 1) & 0x3f) != 0x34) {
 232                 dev_err(&st->i2c->dev, "invalid reg value 0x%02x", val);
 233                 ret = -ENXIO;
 234                 goto err_ret;
 235         }
 236 
 237         ret = itg3200_enable_full_scale(indio_dev);
 238 err_ret:
 239         return ret;
 240 }
 241 
 242 static const struct iio_mount_matrix *
 243 itg3200_get_mount_matrix(const struct iio_dev *indio_dev,
 244                           const struct iio_chan_spec *chan)
 245 {
 246         struct itg3200 *data = iio_priv(indio_dev);
 247 
 248         return &data->orientation;
 249 }
 250 
 251 static const struct iio_chan_spec_ext_info itg3200_ext_info[] = {
 252         IIO_MOUNT_MATRIX(IIO_SHARED_BY_DIR, itg3200_get_mount_matrix),
 253         { }
 254 };
 255 
 256 #define ITG3200_ST                                              \
 257         { .sign = 's', .realbits = 16, .storagebits = 16, .endianness = IIO_BE }
 258 
 259 #define ITG3200_GYRO_CHAN(_mod) { \
 260         .type = IIO_ANGL_VEL, \
 261         .modified = 1, \
 262         .channel2 = IIO_MOD_ ## _mod, \
 263         .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
 264         .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
 265         .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \
 266         .address = ITG3200_REG_GYRO_ ## _mod ## OUT_H, \
 267         .scan_index = ITG3200_SCAN_GYRO_ ## _mod, \
 268         .scan_type = ITG3200_ST, \
 269         .ext_info = itg3200_ext_info, \
 270 }
 271 
 272 static const struct iio_chan_spec itg3200_channels[] = {
 273         {
 274                 .type = IIO_TEMP,
 275                 .channel2 = IIO_NO_MOD,
 276                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
 277                 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
 278                 BIT(IIO_CHAN_INFO_SCALE),
 279                 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
 280                 .address = ITG3200_REG_TEMP_OUT_H,
 281                 .scan_index = ITG3200_SCAN_TEMP,
 282                 .scan_type = ITG3200_ST,
 283         },
 284         ITG3200_GYRO_CHAN(X),
 285         ITG3200_GYRO_CHAN(Y),
 286         ITG3200_GYRO_CHAN(Z),
 287         IIO_CHAN_SOFT_TIMESTAMP(ITG3200_SCAN_ELEMENTS),
 288 };
 289 
 290 static const struct iio_info itg3200_info = {
 291         .read_raw = &itg3200_read_raw,
 292         .write_raw = &itg3200_write_raw,
 293 };
 294 
 295 static const unsigned long itg3200_available_scan_masks[] = { 0xffffffff, 0x0 };
 296 
 297 static int itg3200_probe(struct i2c_client *client,
 298                 const struct i2c_device_id *id)
 299 {
 300         int ret;
 301         struct itg3200 *st;
 302         struct iio_dev *indio_dev;
 303 
 304         dev_dbg(&client->dev, "probe I2C dev with IRQ %i", client->irq);
 305 
 306         indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st));
 307         if (!indio_dev)
 308                 return -ENOMEM;
 309 
 310         st = iio_priv(indio_dev);
 311 
 312         ret = iio_read_mount_matrix(&client->dev, "mount-matrix",
 313                                 &st->orientation);
 314         if (ret)
 315                 return ret;
 316 
 317         i2c_set_clientdata(client, indio_dev);
 318         st->i2c = client;
 319 
 320         indio_dev->dev.parent = &client->dev;
 321         indio_dev->name = client->dev.driver->name;
 322         indio_dev->channels = itg3200_channels;
 323         indio_dev->num_channels = ARRAY_SIZE(itg3200_channels);
 324         indio_dev->available_scan_masks = itg3200_available_scan_masks;
 325         indio_dev->info = &itg3200_info;
 326         indio_dev->modes = INDIO_DIRECT_MODE;
 327 
 328         ret = itg3200_buffer_configure(indio_dev);
 329         if (ret)
 330                 return ret;
 331 
 332         if (client->irq) {
 333                 ret = itg3200_probe_trigger(indio_dev);
 334                 if (ret)
 335                         goto error_unconfigure_buffer;
 336         }
 337 
 338         ret = itg3200_initial_setup(indio_dev);
 339         if (ret)
 340                 goto error_remove_trigger;
 341 
 342         ret = iio_device_register(indio_dev);
 343         if (ret)
 344                 goto error_remove_trigger;
 345 
 346         return 0;
 347 
 348 error_remove_trigger:
 349         if (client->irq)
 350                 itg3200_remove_trigger(indio_dev);
 351 error_unconfigure_buffer:
 352         itg3200_buffer_unconfigure(indio_dev);
 353         return ret;
 354 }
 355 
 356 static int itg3200_remove(struct i2c_client *client)
 357 {
 358         struct iio_dev *indio_dev = i2c_get_clientdata(client);
 359 
 360         iio_device_unregister(indio_dev);
 361 
 362         if (client->irq)
 363                 itg3200_remove_trigger(indio_dev);
 364 
 365         itg3200_buffer_unconfigure(indio_dev);
 366 
 367         return 0;
 368 }
 369 
 370 static int __maybe_unused itg3200_suspend(struct device *dev)
 371 {
 372         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 373         struct itg3200 *st = iio_priv(indio_dev);
 374 
 375         dev_dbg(&st->i2c->dev, "suspend device");
 376 
 377         return itg3200_write_reg_8(indio_dev, ITG3200_REG_POWER_MANAGEMENT,
 378                                    ITG3200_SLEEP);
 379 }
 380 
 381 static int __maybe_unused itg3200_resume(struct device *dev)
 382 {
 383         struct iio_dev *indio_dev = dev_get_drvdata(dev);
 384 
 385         return itg3200_initial_setup(indio_dev);
 386 }
 387 
 388 static SIMPLE_DEV_PM_OPS(itg3200_pm_ops, itg3200_suspend, itg3200_resume);
 389 
 390 static const struct i2c_device_id itg3200_id[] = {
 391         { "itg3200", 0 },
 392         { }
 393 };
 394 MODULE_DEVICE_TABLE(i2c, itg3200_id);
 395 
 396 static const struct of_device_id itg3200_of_match[] = {
 397         { .compatible = "invensense,itg3200" },
 398         { }
 399 };
 400 MODULE_DEVICE_TABLE(of, itg3200_of_match);
 401 
 402 static struct i2c_driver itg3200_driver = {
 403         .driver = {
 404                 .name   = "itg3200",
 405                 .of_match_table = itg3200_of_match,
 406                 .pm     = &itg3200_pm_ops,
 407         },
 408         .id_table       = itg3200_id,
 409         .probe          = itg3200_probe,
 410         .remove         = itg3200_remove,
 411 };
 412 
 413 module_i2c_driver(itg3200_driver);
 414 
 415 MODULE_AUTHOR("Christian Strobel <christian.strobel@iis.fraunhofer.de>");
 416 MODULE_DESCRIPTION("ITG3200 Gyroscope I2C driver");
 417 MODULE_LICENSE("GPL v2");

/* [<][>][^][v][top][bottom][index][help] */