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/slab.h> 19 #include <linux/stat.h> 20 #include <linux/module.h> 21 #include <linux/mutex.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, ®val); 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 ®val); 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 struct itg3200 *st = iio_priv(indio_dev); 136 int ret; 137 u8 t; 138 139 switch (mask) { 140 case IIO_CHAN_INFO_SAMP_FREQ: 141 if (val == 0 || val2 != 0) 142 return -EINVAL; 143 144 mutex_lock(&st->lock); 145 146 ret = itg3200_read_reg_8(indio_dev, ITG3200_REG_DLPF, &t); 147 if (ret) { 148 mutex_unlock(&st->lock); 149 return ret; 150 } 151 t = ((t & ITG3200_DLPF_CFG_MASK) ? 1000u : 8000u) / val - 1; 152 153 ret = itg3200_write_reg_8(indio_dev, 154 ITG3200_REG_SAMPLE_RATE_DIV, 155 t); 156 157 mutex_unlock(&st->lock); 158 return ret; 159 160 default: 161 return -EINVAL; 162 } 163 } 164 165 /* 166 * Reset device and internal registers to the power-up-default settings 167 * Use the gyro clock as reference, as suggested by the datasheet 168 */ 169 static int itg3200_reset(struct iio_dev *indio_dev) 170 { 171 struct itg3200 *st = iio_priv(indio_dev); 172 int ret; 173 174 dev_dbg(&st->i2c->dev, "reset device"); 175 176 ret = itg3200_write_reg_8(indio_dev, 177 ITG3200_REG_POWER_MANAGEMENT, 178 ITG3200_RESET); 179 if (ret) { 180 dev_err(&st->i2c->dev, "error resetting device"); 181 goto error_ret; 182 } 183 184 /* Wait for PLL (1ms according to datasheet) */ 185 udelay(1500); 186 187 ret = itg3200_write_reg_8(indio_dev, 188 ITG3200_REG_IRQ_CONFIG, 189 ITG3200_IRQ_ACTIVE_HIGH | 190 ITG3200_IRQ_PUSH_PULL | 191 ITG3200_IRQ_LATCH_50US_PULSE | 192 ITG3200_IRQ_LATCH_CLEAR_ANY); 193 194 if (ret) 195 dev_err(&st->i2c->dev, "error init device"); 196 197 error_ret: 198 return ret; 199 } 200 201 /* itg3200_enable_full_scale() - Disables the digital low pass filter */ 202 static int itg3200_enable_full_scale(struct iio_dev *indio_dev) 203 { 204 u8 val; 205 int ret; 206 207 ret = itg3200_read_reg_8(indio_dev, ITG3200_REG_DLPF, &val); 208 if (ret) 209 goto err_ret; 210 211 val |= ITG3200_DLPF_FS_SEL_2000; 212 return itg3200_write_reg_8(indio_dev, ITG3200_REG_DLPF, val); 213 214 err_ret: 215 return ret; 216 } 217 218 static int itg3200_initial_setup(struct iio_dev *indio_dev) 219 { 220 struct itg3200 *st = iio_priv(indio_dev); 221 int ret; 222 u8 val; 223 224 ret = itg3200_reset(indio_dev); 225 if (ret) 226 goto err_ret; 227 228 ret = itg3200_read_reg_8(indio_dev, ITG3200_REG_ADDRESS, &val); 229 if (ret) 230 goto err_ret; 231 232 if (((val >> 1) & 0x3f) != 0x34) { 233 dev_err(&st->i2c->dev, "invalid reg value 0x%02x", val); 234 ret = -ENXIO; 235 goto err_ret; 236 } 237 238 ret = itg3200_enable_full_scale(indio_dev); 239 err_ret: 240 return ret; 241 } 242 243 static const struct iio_mount_matrix * 244 itg3200_get_mount_matrix(const struct iio_dev *indio_dev, 245 const struct iio_chan_spec *chan) 246 { 247 struct itg3200 *data = iio_priv(indio_dev); 248 249 return &data->orientation; 250 } 251 252 static const struct iio_chan_spec_ext_info itg3200_ext_info[] = { 253 IIO_MOUNT_MATRIX(IIO_SHARED_BY_DIR, itg3200_get_mount_matrix), 254 { } 255 }; 256 257 #define ITG3200_ST \ 258 { .sign = 's', .realbits = 16, .storagebits = 16, .endianness = IIO_BE } 259 260 #define ITG3200_GYRO_CHAN(_mod) { \ 261 .type = IIO_ANGL_VEL, \ 262 .modified = 1, \ 263 .channel2 = IIO_MOD_ ## _mod, \ 264 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ 265 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ 266 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), \ 267 .address = ITG3200_REG_GYRO_ ## _mod ## OUT_H, \ 268 .scan_index = ITG3200_SCAN_GYRO_ ## _mod, \ 269 .scan_type = ITG3200_ST, \ 270 .ext_info = itg3200_ext_info, \ 271 } 272 273 static const struct iio_chan_spec itg3200_channels[] = { 274 { 275 .type = IIO_TEMP, 276 .channel2 = IIO_NO_MOD, 277 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), 278 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) | 279 BIT(IIO_CHAN_INFO_SCALE), 280 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), 281 .address = ITG3200_REG_TEMP_OUT_H, 282 .scan_index = ITG3200_SCAN_TEMP, 283 .scan_type = ITG3200_ST, 284 }, 285 ITG3200_GYRO_CHAN(X), 286 ITG3200_GYRO_CHAN(Y), 287 ITG3200_GYRO_CHAN(Z), 288 IIO_CHAN_SOFT_TIMESTAMP(ITG3200_SCAN_ELEMENTS), 289 }; 290 291 static const struct iio_info itg3200_info = { 292 .read_raw = &itg3200_read_raw, 293 .write_raw = &itg3200_write_raw, 294 }; 295 296 static const unsigned long itg3200_available_scan_masks[] = { 0xffffffff, 0x0 }; 297 298 static int itg3200_probe(struct i2c_client *client) 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, &st->orientation); 313 if (ret) 314 return ret; 315 316 i2c_set_clientdata(client, indio_dev); 317 st->i2c = client; 318 319 indio_dev->name = client->dev.driver->name; 320 indio_dev->channels = itg3200_channels; 321 indio_dev->num_channels = ARRAY_SIZE(itg3200_channels); 322 indio_dev->available_scan_masks = itg3200_available_scan_masks; 323 indio_dev->info = &itg3200_info; 324 indio_dev->modes = INDIO_DIRECT_MODE; 325 326 ret = itg3200_buffer_configure(indio_dev); 327 if (ret) 328 return ret; 329 330 if (client->irq) { 331 ret = itg3200_probe_trigger(indio_dev); 332 if (ret) 333 goto error_unconfigure_buffer; 334 } 335 336 ret = itg3200_initial_setup(indio_dev); 337 if (ret) 338 goto error_remove_trigger; 339 340 mutex_init(&st->lock); 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 void 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 } 367 368 static int itg3200_suspend(struct device *dev) 369 { 370 struct iio_dev *indio_dev = dev_get_drvdata(dev); 371 struct itg3200 *st = iio_priv(indio_dev); 372 373 dev_dbg(&st->i2c->dev, "suspend device"); 374 375 return itg3200_write_reg_8(indio_dev, ITG3200_REG_POWER_MANAGEMENT, 376 ITG3200_SLEEP); 377 } 378 379 static int itg3200_resume(struct device *dev) 380 { 381 struct iio_dev *indio_dev = dev_get_drvdata(dev); 382 383 return itg3200_initial_setup(indio_dev); 384 } 385 386 static DEFINE_SIMPLE_DEV_PM_OPS(itg3200_pm_ops, itg3200_suspend, 387 itg3200_resume); 388 389 static const struct i2c_device_id itg3200_id[] = { 390 { "itg3200", 0 }, 391 { } 392 }; 393 MODULE_DEVICE_TABLE(i2c, itg3200_id); 394 395 static const struct of_device_id itg3200_of_match[] = { 396 { .compatible = "invensense,itg3200" }, 397 { } 398 }; 399 MODULE_DEVICE_TABLE(of, itg3200_of_match); 400 401 static struct i2c_driver itg3200_driver = { 402 .driver = { 403 .name = "itg3200", 404 .of_match_table = itg3200_of_match, 405 .pm = pm_sleep_ptr(&itg3200_pm_ops), 406 }, 407 .id_table = itg3200_id, 408 .probe = itg3200_probe, 409 .remove = itg3200_remove, 410 }; 411 412 module_i2c_driver(itg3200_driver); 413 414 MODULE_AUTHOR("Christian Strobel <christian.strobel@iis.fraunhofer.de>"); 415 MODULE_DESCRIPTION("ITG3200 Gyroscope I2C driver"); 416 MODULE_LICENSE("GPL v2"); 417