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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 | // SPDX-License-Identifier: GPL-2.0 /* * Copyright (C) 2019 TDK-InvenSense, Inc. */ #include <linux/kernel.h> #include <linux/device.h> #include <linux/string.h> #include "inv_mpu_aux.h" #include "inv_mpu_iio.h" #include "inv_mpu_magn.h" /* * MPU9xxx magnetometer are AKM chips on I2C aux bus * MPU9150 is AK8975 * MPU9250 is AK8963 */ #define INV_MPU_MAGN_I2C_ADDR 0x0C #define INV_MPU_MAGN_REG_WIA 0x00 #define INV_MPU_MAGN_BITS_WIA 0x48 #define INV_MPU_MAGN_REG_ST1 0x02 #define INV_MPU_MAGN_BIT_DRDY 0x01 #define INV_MPU_MAGN_BIT_DOR 0x02 #define INV_MPU_MAGN_REG_DATA 0x03 #define INV_MPU_MAGN_REG_ST2 0x09 #define INV_MPU_MAGN_BIT_HOFL 0x08 #define INV_MPU_MAGN_BIT_BITM 0x10 #define INV_MPU_MAGN_REG_CNTL1 0x0A #define INV_MPU_MAGN_BITS_MODE_PWDN 0x00 #define INV_MPU_MAGN_BITS_MODE_SINGLE 0x01 #define INV_MPU_MAGN_BITS_MODE_FUSE 0x0F #define INV_MPU9250_MAGN_BIT_OUTPUT_BIT 0x10 #define INV_MPU9250_MAGN_REG_CNTL2 0x0B #define INV_MPU9250_MAGN_BIT_SRST 0x01 #define INV_MPU_MAGN_REG_ASAX 0x10 #define INV_MPU_MAGN_REG_ASAY 0x11 #define INV_MPU_MAGN_REG_ASAZ 0x12 /* Magnetometer maximum frequency */ #define INV_MPU_MAGN_FREQ_HZ_MAX 50 static bool inv_magn_supported(const struct inv_mpu6050_state *st) { switch (st->chip_type) { case INV_MPU9150: case INV_MPU9250: case INV_MPU9255: return true; default: return false; } } /* init magnetometer chip */ static int inv_magn_init(struct inv_mpu6050_state *st) { uint8_t val; uint8_t asa[3]; int32_t sensitivity; int ret; /* check whoami */ ret = inv_mpu_aux_read(st, INV_MPU_MAGN_I2C_ADDR, INV_MPU_MAGN_REG_WIA, &val, sizeof(val)); if (ret) return ret; if (val != INV_MPU_MAGN_BITS_WIA) return -ENODEV; /* software reset for MPU925x only */ switch (st->chip_type) { case INV_MPU9250: case INV_MPU9255: ret = inv_mpu_aux_write(st, INV_MPU_MAGN_I2C_ADDR, INV_MPU9250_MAGN_REG_CNTL2, INV_MPU9250_MAGN_BIT_SRST); if (ret) return ret; break; default: break; } /* read fuse ROM data */ ret = inv_mpu_aux_write(st, INV_MPU_MAGN_I2C_ADDR, INV_MPU_MAGN_REG_CNTL1, INV_MPU_MAGN_BITS_MODE_FUSE); if (ret) return ret; ret = inv_mpu_aux_read(st, INV_MPU_MAGN_I2C_ADDR, INV_MPU_MAGN_REG_ASAX, asa, sizeof(asa)); if (ret) return ret; /* switch back to power-down */ ret = inv_mpu_aux_write(st, INV_MPU_MAGN_I2C_ADDR, INV_MPU_MAGN_REG_CNTL1, INV_MPU_MAGN_BITS_MODE_PWDN); if (ret) return ret; /* * Sensor sentivity * 1 uT = 0.01 G and value is in micron (1e6) * sensitvity = x uT * 0.01 * 1e6 */ switch (st->chip_type) { case INV_MPU9150: /* sensor sensitivity is 0.3 uT */ sensitivity = 3000; break; case INV_MPU9250: case INV_MPU9255: /* sensor sensitivity in 16 bits mode: 0.15 uT */ sensitivity = 1500; break; default: return -EINVAL; } /* * Sensitivity adjustement and scale to Gauss * * Hadj = H * (((ASA - 128) * 0.5 / 128) + 1) * Factor simplification: * Hadj = H * ((ASA + 128) / 256) * * raw_to_gauss = Hadj * sensitivity */ st->magn_raw_to_gauss[0] = (((int32_t)asa[0] + 128) * sensitivity) / 256; st->magn_raw_to_gauss[1] = (((int32_t)asa[1] + 128) * sensitivity) / 256; st->magn_raw_to_gauss[2] = (((int32_t)asa[2] + 128) * sensitivity) / 256; return 0; } /** * inv_mpu_magn_probe() - probe and setup magnetometer chip * @st: driver internal state * * Returns 0 on success, a negative error code otherwise * * It is probing the chip and setting up all needed i2c transfers. * Noop if there is no magnetometer in the chip. */ int inv_mpu_magn_probe(struct inv_mpu6050_state *st) { uint8_t val; int ret; /* quit if chip is not supported */ if (!inv_magn_supported(st)) return 0; /* configure i2c master aux port */ ret = inv_mpu_aux_init(st); if (ret) return ret; /* check and init mag chip */ ret = inv_magn_init(st); if (ret) return ret; /* * configure mpu i2c master accesses * i2c SLV0: read sensor data, 7 bytes data(6)-ST2 * Byte swap data to store them in big-endian in impair address groups */ ret = regmap_write(st->map, INV_MPU6050_REG_I2C_SLV_ADDR(0), INV_MPU6050_BIT_I2C_SLV_RNW | INV_MPU_MAGN_I2C_ADDR); if (ret) return ret; ret = regmap_write(st->map, INV_MPU6050_REG_I2C_SLV_REG(0), INV_MPU_MAGN_REG_DATA); if (ret) return ret; ret = regmap_write(st->map, INV_MPU6050_REG_I2C_SLV_CTRL(0), INV_MPU6050_BIT_SLV_EN | INV_MPU6050_BIT_SLV_BYTE_SW | INV_MPU6050_BIT_SLV_GRP | INV_MPU9X50_BYTES_MAGN); if (ret) return ret; /* i2c SLV1: launch single measurement */ ret = regmap_write(st->map, INV_MPU6050_REG_I2C_SLV_ADDR(1), INV_MPU_MAGN_I2C_ADDR); if (ret) return ret; ret = regmap_write(st->map, INV_MPU6050_REG_I2C_SLV_REG(1), INV_MPU_MAGN_REG_CNTL1); if (ret) return ret; /* add 16 bits mode for MPU925x */ val = INV_MPU_MAGN_BITS_MODE_SINGLE; switch (st->chip_type) { case INV_MPU9250: case INV_MPU9255: val |= INV_MPU9250_MAGN_BIT_OUTPUT_BIT; break; default: break; } ret = regmap_write(st->map, INV_MPU6050_REG_I2C_SLV_DO(1), val); if (ret) return ret; return regmap_write(st->map, INV_MPU6050_REG_I2C_SLV_CTRL(1), INV_MPU6050_BIT_SLV_EN | 1); } /** * inv_mpu_magn_set_rate() - set magnetometer sampling rate * @st: driver internal state * @fifo_rate: mpu set fifo rate * * Returns 0 on success, a negative error code otherwise * * Limit sampling frequency to the maximum value supported by the * magnetometer chip. Resulting in duplicated data for higher frequencies. * Noop if there is no magnetometer in the chip. */ int inv_mpu_magn_set_rate(const struct inv_mpu6050_state *st, int fifo_rate) { uint8_t d; /* quit if chip is not supported */ if (!inv_magn_supported(st)) return 0; /* * update i2c master delay to limit mag sampling to max frequency * compute fifo_rate divider d: rate = fifo_rate / (d + 1) */ if (fifo_rate > INV_MPU_MAGN_FREQ_HZ_MAX) d = fifo_rate / INV_MPU_MAGN_FREQ_HZ_MAX - 1; else d = 0; return regmap_write(st->map, INV_MPU6050_REG_I2C_SLV4_CTRL, d); } /** * inv_mpu_magn_set_orient() - fill magnetometer mounting matrix * @st: driver internal state * * Returns 0 on success, a negative error code otherwise * * Fill magnetometer mounting matrix using the provided chip matrix. */ int inv_mpu_magn_set_orient(struct inv_mpu6050_state *st) { const char *orient; char *str; int i; /* fill magnetometer orientation */ switch (st->chip_type) { case INV_MPU9150: case INV_MPU9250: case INV_MPU9255: /* x <- y */ st->magn_orient.rotation[0] = st->orientation.rotation[3]; st->magn_orient.rotation[1] = st->orientation.rotation[4]; st->magn_orient.rotation[2] = st->orientation.rotation[5]; /* y <- x */ st->magn_orient.rotation[3] = st->orientation.rotation[0]; st->magn_orient.rotation[4] = st->orientation.rotation[1]; st->magn_orient.rotation[5] = st->orientation.rotation[2]; /* z <- -z */ for (i = 0; i < 3; ++i) { orient = st->orientation.rotation[6 + i]; /* use length + 2 for adding minus sign if needed */ str = devm_kzalloc(regmap_get_device(st->map), strlen(orient) + 2, GFP_KERNEL); if (str == NULL) return -ENOMEM; if (strcmp(orient, "0") == 0) { strcpy(str, orient); } else if (orient[0] == '-') { strcpy(str, &orient[1]); } else { str[0] = '-'; strcpy(&str[1], orient); } st->magn_orient.rotation[6 + i] = str; } break; default: st->magn_orient = st->orientation; break; } return 0; } /** * inv_mpu_magn_read() - read magnetometer data * @st: driver internal state * @axis: IIO modifier axis value * @val: store corresponding axis value * * Returns 0 on success, a negative error code otherwise */ int inv_mpu_magn_read(const struct inv_mpu6050_state *st, int axis, int *val) { unsigned int user_ctrl, status; __be16 data[3]; uint8_t addr; uint8_t d; unsigned int period_ms; int ret; /* quit if chip is not supported */ if (!inv_magn_supported(st)) return -ENODEV; /* Mag data: X - Y - Z */ switch (axis) { case IIO_MOD_X: addr = 0; break; case IIO_MOD_Y: addr = 1; break; case IIO_MOD_Z: addr = 2; break; default: return -EINVAL; } /* set sample rate to max mag freq */ d = INV_MPU6050_FIFO_RATE_TO_DIVIDER(INV_MPU_MAGN_FREQ_HZ_MAX); ret = regmap_write(st->map, st->reg->sample_rate_div, d); if (ret) return ret; /* start i2c master, wait for xfer, stop */ user_ctrl = st->chip_config.user_ctrl | INV_MPU6050_BIT_I2C_MST_EN; ret = regmap_write(st->map, st->reg->user_ctrl, user_ctrl); if (ret) return ret; /* need to wait 2 periods + half-period margin */ period_ms = 1000 / INV_MPU_MAGN_FREQ_HZ_MAX; msleep(period_ms * 2 + period_ms / 2); user_ctrl = st->chip_config.user_ctrl; ret = regmap_write(st->map, st->reg->user_ctrl, user_ctrl); if (ret) return ret; /* restore sample rate */ d = st->chip_config.divider; ret = regmap_write(st->map, st->reg->sample_rate_div, d); if (ret) return ret; /* check i2c status and read raw data */ ret = regmap_read(st->map, INV_MPU6050_REG_I2C_MST_STATUS, &status); if (ret) return ret; if (status & INV_MPU6050_BIT_I2C_SLV0_NACK || status & INV_MPU6050_BIT_I2C_SLV1_NACK) return -EIO; ret = regmap_bulk_read(st->map, INV_MPU6050_REG_EXT_SENS_DATA, data, sizeof(data)); if (ret) return ret; *val = (int16_t)be16_to_cpu(data[addr]); return IIO_VAL_INT; } |