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, ®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 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"); 418