drivers/iio/common/ssp_sensors/ssp_spi.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *  Copyright (C) 2014, Samsung Electronics Co. Ltd. All Rights Reserved.
   4  */
   5
   6 #include "ssp.h"
   7
   8 #define SSP_DEV (&data->spi->dev)
   9 #define SSP_GET_MESSAGE_TYPE(data) (data & (3 << SSP_RW))
  10
  11 /*
  12  * SSP -> AP Instruction
  13  * They tell what packet type can be expected. In the future there will
  14  * be less of them. BYPASS means common sensor packets with accel, gyro,
  15  * hrm etc. data. LIBRARY and META are mock-up's for now.
  16  */
  17 #define SSP_MSG2AP_INST_BYPASS_DATA             0x37
  18 #define SSP_MSG2AP_INST_LIBRARY_DATA            0x01
  19 #define SSP_MSG2AP_INST_DEBUG_DATA              0x03
  20 #define SSP_MSG2AP_INST_BIG_DATA                0x04
  21 #define SSP_MSG2AP_INST_META_DATA               0x05
  22 #define SSP_MSG2AP_INST_TIME_SYNC               0x06
  23 #define SSP_MSG2AP_INST_RESET                   0x07
  24
  25 #define SSP_UNIMPLEMENTED -1
  26
  27 struct ssp_msg_header {
  28         u8 cmd;
  29         __le16 length;
  30         __le16 options;
  31         __le32 data;
  32 } __attribute__((__packed__));
  33
  34 struct ssp_msg {
  35         u16 length;
  36         u16 options;
  37         struct list_head list;
  38         struct completion *done;
  39         struct ssp_msg_header *h;
  40         char *buffer;
  41 };
  42
  43 static const int ssp_offset_map[SSP_SENSOR_MAX] = {
  44         [SSP_ACCELEROMETER_SENSOR] =            SSP_ACCELEROMETER_SIZE +
  45                                                 SSP_TIME_SIZE,
  46         [SSP_GYROSCOPE_SENSOR] =                SSP_GYROSCOPE_SIZE +
  47                                                 SSP_TIME_SIZE,
  48         [SSP_GEOMAGNETIC_UNCALIB_SENSOR] =      SSP_UNIMPLEMENTED,
  49         [SSP_GEOMAGNETIC_RAW] =                 SSP_UNIMPLEMENTED,
  50         [SSP_GEOMAGNETIC_SENSOR] =              SSP_UNIMPLEMENTED,
  51         [SSP_PRESSURE_SENSOR] =                 SSP_UNIMPLEMENTED,
  52         [SSP_GESTURE_SENSOR] =                  SSP_UNIMPLEMENTED,
  53         [SSP_PROXIMITY_SENSOR] =                SSP_UNIMPLEMENTED,
  54         [SSP_TEMPERATURE_HUMIDITY_SENSOR] =     SSP_UNIMPLEMENTED,
  55         [SSP_LIGHT_SENSOR] =                    SSP_UNIMPLEMENTED,
  56         [SSP_PROXIMITY_RAW] =                   SSP_UNIMPLEMENTED,
  57         [SSP_ORIENTATION_SENSOR] =              SSP_UNIMPLEMENTED,
  58         [SSP_STEP_DETECTOR] =                   SSP_UNIMPLEMENTED,
  59         [SSP_SIG_MOTION_SENSOR] =               SSP_UNIMPLEMENTED,
  60         [SSP_GYRO_UNCALIB_SENSOR] =             SSP_UNIMPLEMENTED,
  61         [SSP_GAME_ROTATION_VECTOR] =            SSP_UNIMPLEMENTED,
  62         [SSP_ROTATION_VECTOR] =                 SSP_UNIMPLEMENTED,
  63         [SSP_STEP_COUNTER] =                    SSP_UNIMPLEMENTED,
  64         [SSP_BIO_HRM_RAW] =                     SSP_BIO_HRM_RAW_SIZE +
  65                                                 SSP_TIME_SIZE,
  66         [SSP_BIO_HRM_RAW_FAC] =                 SSP_BIO_HRM_RAW_FAC_SIZE +
  67                                                 SSP_TIME_SIZE,
  68         [SSP_BIO_HRM_LIB] =                     SSP_BIO_HRM_LIB_SIZE +
  69                                                 SSP_TIME_SIZE,
  70 };
  71
  72 #define SSP_HEADER_SIZE         (sizeof(struct ssp_msg_header))
  73 #define SSP_HEADER_SIZE_ALIGNED (ALIGN(SSP_HEADER_SIZE, 4))
  74
  75 static struct ssp_msg *ssp_create_msg(u8 cmd, u16 len, u16 opt, u32 data)
  76 {
  77         struct ssp_msg_header h;
  78         struct ssp_msg *msg;
  79
  80         msg = kzalloc(sizeof(*msg), GFP_KERNEL);
  81         if (!msg)
  82                 return NULL;
  83
  84         h.cmd = cmd;
  85         h.length = cpu_to_le16(len);
  86         h.options = cpu_to_le16(opt);
  87         h.data = cpu_to_le32(data);
  88
  89         msg->buffer = kzalloc(SSP_HEADER_SIZE_ALIGNED + len,
  90                               GFP_KERNEL | GFP_DMA);
  91         if (!msg->buffer) {
  92                 kfree(msg);
  93                 return NULL;
  94         }
  95
  96         msg->length = len;
  97         msg->options = opt;
  98
  99         memcpy(msg->buffer, &h, SSP_HEADER_SIZE);
 100
 101         return msg;
 102 }
 103
 104 /*
 105  * It is a bit heavy to do it this way but often the function is used to compose
 106  * the message from smaller chunks which are placed on the stack.  Often the
 107  * chunks are small so memcpy should be optimalized.
 108  */
 109 static inline void ssp_fill_buffer(struct ssp_msg *m, unsigned int offset,
 110                                    const void *src, unsigned int len)
 111 {
 112         memcpy(&m->buffer[SSP_HEADER_SIZE_ALIGNED + offset], src, len);
 113 }
 114
 115 static inline void ssp_get_buffer(struct ssp_msg *m, unsigned int offset,
 116                                   void *dest, unsigned int len)
 117 {
 118         memcpy(dest, &m->buffer[SSP_HEADER_SIZE_ALIGNED + offset],  len);
 119 }
 120
 121 #define SSP_GET_BUFFER_AT_INDEX(m, index) \
 122         (m->buffer[SSP_HEADER_SIZE_ALIGNED + index])
 123 #define SSP_SET_BUFFER_AT_INDEX(m, index, val) \
 124         (m->buffer[SSP_HEADER_SIZE_ALIGNED + index] = val)
 125
 126 static void ssp_clean_msg(struct ssp_msg *m)
 127 {
 128         kfree(m->buffer);
 129         kfree(m);
 130 }
 131
 132 static int ssp_print_mcu_debug(char *data_frame, int *data_index,
 133                                int received_len)
 134 {
 135         int length = data_frame[(*data_index)++];
 136
 137         if (length > received_len - *data_index || length <= 0) {
 138                 ssp_dbg("[SSP]: MSG From MCU-invalid debug length(%d/%d)\n",
 139                         length, received_len);
 140                 return -EPROTO;
 141         }
 142
 143         ssp_dbg("[SSP]: MSG From MCU - %s\n", &data_frame[*data_index]);
 144
 145         *data_index += length;
 146
 147         return 0;
 148 }
 149
 150 /*
 151  * It was designed that way - additional lines to some kind of handshake,
 152  * please do not ask why - only the firmware guy can know it.
 153  */
 154 static int ssp_check_lines(struct ssp_data *data, bool state)
 155 {
 156         int delay_cnt = 0;
 157
 158         gpiod_set_value_cansleep(data->ap_mcu_gpiod, state);
 159
 160         while (gpiod_get_value_cansleep(data->mcu_ap_gpiod) != state) {
 161                 usleep_range(3000, 3500);
 162
 163                 if (data->shut_down || delay_cnt++ > 500) {
 164                         dev_err(SSP_DEV, "%s:timeout, hw ack wait fail %d\n",
 165                                 __func__, state);
 166
 167                         if (!state)
 168                                 gpiod_set_value_cansleep(data->ap_mcu_gpiod, 1);
 169
 170                         return -ETIMEDOUT;
 171                 }
 172         }
 173
 174         return 0;
 175 }
 176
 177 static int ssp_do_transfer(struct ssp_data *data, struct ssp_msg *msg,
 178                            struct completion *done, int timeout)
 179 {
 180         int status;
 181         /*
 182          * check if this is a short one way message or the whole transfer has
 183          * second part after an interrupt
 184          */
 185         const bool use_no_irq = msg->length == 0;
 186
 187         if (data->shut_down)
 188                 return -EPERM;
 189
 190         msg->done = done;
 191
 192         mutex_lock(&data->comm_lock);
 193
 194         status = ssp_check_lines(data, false);
 195         if (status < 0)
 196                 goto _error_locked;
 197
 198         status = spi_write(data->spi, msg->buffer, SSP_HEADER_SIZE);
 199         if (status < 0) {
 200                 gpiod_set_value_cansleep(data->ap_mcu_gpiod, 1);
 201                 dev_err(SSP_DEV, "%s spi_write fail\n", __func__);
 202                 goto _error_locked;
 203         }
 204
 205         if (!use_no_irq) {
 206                 mutex_lock(&data->pending_lock);
 207                 list_add_tail(&msg->list, &data->pending_list);
 208                 mutex_unlock(&data->pending_lock);
 209         }
 210
 211         status = ssp_check_lines(data, true);
 212         if (status < 0) {
 213                 if (!use_no_irq) {
 214                         mutex_lock(&data->pending_lock);
 215                         list_del(&msg->list);
 216                         mutex_unlock(&data->pending_lock);
 217                 }
 218                 goto _error_locked;
 219         }
 220
 221         mutex_unlock(&data->comm_lock);
 222
 223         if (!use_no_irq && done)
 224                 if (wait_for_completion_timeout(done,
 225                                                 msecs_to_jiffies(timeout)) ==
 226                     0) {
 227                         mutex_lock(&data->pending_lock);
 228                         list_del(&msg->list);
 229                         mutex_unlock(&data->pending_lock);
 230
 231                         data->timeout_cnt++;
 232                         return -ETIMEDOUT;
 233                 }
 234
 235         return 0;
 236
 237 _error_locked:
 238         mutex_unlock(&data->comm_lock);
 239         data->timeout_cnt++;
 240         return status;
 241 }
 242
 243 static inline int ssp_spi_sync_command(struct ssp_data *data,
 244                                        struct ssp_msg *msg)
 245 {
 246         return ssp_do_transfer(data, msg, NULL, 0);
 247 }
 248
 249 static int ssp_spi_sync(struct ssp_data *data, struct ssp_msg *msg,
 250                         int timeout)
 251 {
 252         DECLARE_COMPLETION_ONSTACK(done);
 253
 254         if (WARN_ON(!msg->length))
 255                 return -EPERM;
 256
 257         return ssp_do_transfer(data, msg, &done, timeout);
 258 }
 259
 260 static int ssp_handle_big_data(struct ssp_data *data, char *dataframe, int *idx)
 261 {
 262         /* mock-up, it will be changed with adding another sensor types */
 263         *idx += 8;
 264         return 0;
 265 }
 266
 267 static int ssp_parse_dataframe(struct ssp_data *data, char *dataframe, int len)
 268 {
 269         int idx, sd;
 270         struct ssp_sensor_data *spd;
 271         struct iio_dev **indio_devs = data->sensor_devs;
 272
 273         for (idx = 0; idx < len;) {
 274                 switch (dataframe[idx++]) {
 275                 case SSP_MSG2AP_INST_BYPASS_DATA:
 276                         if (idx >= len)
 277                                 return -EPROTO;
 278                         sd = dataframe[idx++];
 279                         if (sd < 0 || sd >= SSP_SENSOR_MAX) {
 280                                 dev_err(SSP_DEV,
 281                                         "Mcu data frame1 error %d\n", sd);
 282                                 return -EPROTO;
 283                         }
 284
 285                         if (indio_devs[sd]) {
 286                                 spd = iio_priv(indio_devs[sd]);
 287                                 if (spd->process_data) {
 288                                         if (idx >= len)
 289                                                 return -EPROTO;
 290                                         spd->process_data(indio_devs[sd],
 291                                                           &dataframe[idx],
 292                                                           data->timestamp);
 293                                 }
 294                         } else {
 295                                 dev_err(SSP_DEV, "no client for frame\n");
 296                         }
 297
 298                         idx += ssp_offset_map[sd];
 299                         break;
 300                 case SSP_MSG2AP_INST_DEBUG_DATA:
 301                         if (idx >= len)
 302                                 return -EPROTO;
 303                         sd = ssp_print_mcu_debug(dataframe, &idx, len);
 304                         if (sd) {
 305                                 dev_err(SSP_DEV,
 306                                         "Mcu data frame3 error %d\n", sd);
 307                                 return sd;
 308                         }
 309                         break;
 310                 case SSP_MSG2AP_INST_LIBRARY_DATA:
 311                         idx += len;
 312                         break;
 313                 case SSP_MSG2AP_INST_BIG_DATA:
 314                         ssp_handle_big_data(data, dataframe, &idx);
 315                         break;
 316                 case SSP_MSG2AP_INST_TIME_SYNC:
 317                         data->time_syncing = true;
 318                         break;
 319                 case SSP_MSG2AP_INST_RESET:
 320                         ssp_queue_ssp_refresh_task(data, 0);
 321                         break;
 322                 }
 323         }
 324
 325         if (data->time_syncing)
 326                 data->timestamp = ktime_get_real_ns();
 327
 328         return 0;
 329 }
 330
 331 /* threaded irq */
 332 int ssp_irq_msg(struct ssp_data *data)
 333 {
 334         char *buffer;
 335         u8 msg_type;
 336         int ret;
 337         u16 length, msg_options;
 338         struct ssp_msg *msg = NULL, *iter, *n;
 339
 340         ret = spi_read(data->spi, data->header_buffer, SSP_HEADER_BUFFER_SIZE);
 341         if (ret < 0) {
 342                 dev_err(SSP_DEV, "header read fail\n");
 343                 return ret;
 344         }
 345
 346         length = le16_to_cpu(data->header_buffer[1]);
 347         msg_options = le16_to_cpu(data->header_buffer[0]);
 348
 349         if (length == 0) {
 350                 dev_err(SSP_DEV, "length received from mcu is 0\n");
 351                 return -EINVAL;
 352         }
 353
 354         msg_type = SSP_GET_MESSAGE_TYPE(msg_options);
 355
 356         switch (msg_type) {
 357         case SSP_AP2HUB_READ:
 358         case SSP_AP2HUB_WRITE:
 359                 /*
 360                  * this is a small list, a few elements - the packets can be
 361                  * received with no order
 362                  */
 363                 mutex_lock(&data->pending_lock);
 364                 list_for_each_entry_safe(iter, n, &data->pending_list, list) {
 365                         if (iter->options == msg_options) {
 366                                 list_del(&iter->list);
 367                                 msg = iter;
 368                                 break;
 369                         }
 370                 }
 371
 372                 if (!msg) {
 373                         /*
 374                          * here can be implemented dead messages handling
 375                          * but the slave should not send such ones - it is to
 376                          * check but let's handle this
 377                          */
 378                         buffer = kmalloc(length, GFP_KERNEL | GFP_DMA);
 379                         if (!buffer) {
 380                                 ret = -ENOMEM;
 381                                 goto _unlock;
 382                         }
 383
 384                         /* got dead packet so it is always an error */
 385                         ret = spi_read(data->spi, buffer, length);
 386                         if (ret >= 0)
 387                                 ret = -EPROTO;
 388
 389                         kfree(buffer);
 390
 391                         dev_err(SSP_DEV, "No match error %x\n",
 392                                 msg_options);
 393
 394                         goto _unlock;
 395                 }
 396
 397                 if (msg_type == SSP_AP2HUB_READ)
 398                         ret = spi_read(data->spi,
 399                                        &msg->buffer[SSP_HEADER_SIZE_ALIGNED],
 400                                        msg->length);
 401
 402                 if (msg_type == SSP_AP2HUB_WRITE) {
 403                         ret = spi_write(data->spi,
 404                                         &msg->buffer[SSP_HEADER_SIZE_ALIGNED],
 405                                         msg->length);
 406                         if (msg_options & SSP_AP2HUB_RETURN) {
 407                                 msg->options =
 408                                         SSP_AP2HUB_READ | SSP_AP2HUB_RETURN;
 409                                 msg->length = 1;
 410
 411                                 list_add_tail(&msg->list, &data->pending_list);
 412                                 goto _unlock;
 413                         }
 414                 }
 415
 416                 if (msg->done)
 417                         if (!completion_done(msg->done))
 418                                 complete(msg->done);
 419 _unlock:
 420                 mutex_unlock(&data->pending_lock);
 421                 break;
 422         case SSP_HUB2AP_WRITE:
 423                 buffer = kzalloc(length, GFP_KERNEL | GFP_DMA);
 424                 if (!buffer)
 425                         return -ENOMEM;
 426
 427                 ret = spi_read(data->spi, buffer, length);
 428                 if (ret < 0) {
 429                         dev_err(SSP_DEV, "spi read fail\n");
 430                         kfree(buffer);
 431                         break;
 432                 }
 433
 434                 ret = ssp_parse_dataframe(data, buffer, length);
 435
 436                 kfree(buffer);
 437                 break;
 438
 439         default:
 440                 dev_err(SSP_DEV, "unknown msg type\n");
 441                 return -EPROTO;
 442         }
 443
 444         return ret;
 445 }
 446
 447 void ssp_clean_pending_list(struct ssp_data *data)
 448 {
 449         struct ssp_msg *msg, *n;
 450
 451         mutex_lock(&data->pending_lock);
 452         list_for_each_entry_safe(msg, n, &data->pending_list, list) {
 453                 list_del(&msg->list);
 454
 455                 if (msg->done)
 456                         if (!completion_done(msg->done))
 457                                 complete(msg->done);
 458         }
 459         mutex_unlock(&data->pending_lock);
 460 }
 461
 462 int ssp_command(struct ssp_data *data, char command, int arg)
 463 {
 464         int ret;
 465         struct ssp_msg *msg;
 466
 467         msg = ssp_create_msg(command, 0, SSP_AP2HUB_WRITE, arg);
 468         if (!msg)
 469                 return -ENOMEM;
 470
 471         ssp_dbg("%s - command 0x%x %d\n", __func__, command, arg);
 472
 473         ret = ssp_spi_sync_command(data, msg);
 474         ssp_clean_msg(msg);
 475
 476         return ret;
 477 }
 478
 479 int ssp_send_instruction(struct ssp_data *data, u8 inst, u8 sensor_type,
 480                          u8 *send_buf, u8 length)
 481 {
 482         int ret;
 483         struct ssp_msg *msg;
 484
 485         if (data->fw_dl_state == SSP_FW_DL_STATE_DOWNLOADING) {
 486                 dev_err(SSP_DEV, "%s - Skip Inst! DL state = %d\n",
 487                         __func__, data->fw_dl_state);
 488                 return -EBUSY;
 489         } else if (!(data->available_sensors & BIT(sensor_type)) &&
 490                    (inst <= SSP_MSG2SSP_INST_CHANGE_DELAY)) {
 491                 dev_err(SSP_DEV, "%s - Bypass Inst Skip! - %u\n",
 492                         __func__, sensor_type);
 493                 return -EIO; /* just fail */
 494         }
 495
 496         msg = ssp_create_msg(inst, length + 2, SSP_AP2HUB_WRITE, 0);
 497         if (!msg)
 498                 return -ENOMEM;
 499
 500         ssp_fill_buffer(msg, 0, &sensor_type, 1);
 501         ssp_fill_buffer(msg, 1, send_buf, length);
 502
 503         ssp_dbg("%s - Inst = 0x%x, Sensor Type = 0x%x, data = %u\n",
 504                 __func__, inst, sensor_type, send_buf[1]);
 505
 506         ret = ssp_spi_sync(data, msg, 1000);
 507         ssp_clean_msg(msg);
 508
 509         return ret;
 510 }
 511
 512 int ssp_get_chipid(struct ssp_data *data)
 513 {
 514         int ret;
 515         char buffer;
 516         struct ssp_msg *msg;
 517
 518         msg = ssp_create_msg(SSP_MSG2SSP_AP_WHOAMI, 1, SSP_AP2HUB_READ, 0);
 519         if (!msg)
 520                 return -ENOMEM;
 521
 522         ret = ssp_spi_sync(data, msg, 1000);
 523
 524         buffer = SSP_GET_BUFFER_AT_INDEX(msg, 0);
 525
 526         ssp_clean_msg(msg);
 527
 528         return ret < 0 ? ret : buffer;
 529 }
 530
 531 int ssp_set_magnetic_matrix(struct ssp_data *data)
 532 {
 533         int ret;
 534         struct ssp_msg *msg;
 535
 536         msg = ssp_create_msg(SSP_MSG2SSP_AP_SET_MAGNETIC_STATIC_MATRIX,
 537                              data->sensorhub_info->mag_length, SSP_AP2HUB_WRITE,
 538                              0);
 539         if (!msg)
 540                 return -ENOMEM;
 541
 542         ssp_fill_buffer(msg, 0, data->sensorhub_info->mag_table,
 543                         data->sensorhub_info->mag_length);
 544
 545         ret = ssp_spi_sync(data, msg, 1000);
 546         ssp_clean_msg(msg);
 547
 548         return ret;
 549 }
 550
 551 unsigned int ssp_get_sensor_scanning_info(struct ssp_data *data)
 552 {
 553         int ret;
 554         __le32 result;
 555         u32 cpu_result = 0;
 556
 557         struct ssp_msg *msg = ssp_create_msg(SSP_MSG2SSP_AP_SENSOR_SCANNING, 4,
 558                                              SSP_AP2HUB_READ, 0);
 559         if (!msg)
 560                 return 0;
 561
 562         ret = ssp_spi_sync(data, msg, 1000);
 563         if (ret < 0) {
 564                 dev_err(SSP_DEV, "%s - spi read fail %d\n", __func__, ret);
 565                 goto _exit;
 566         }
 567
 568         ssp_get_buffer(msg, 0, &result, 4);
 569         cpu_result = le32_to_cpu(result);
 570
 571         dev_info(SSP_DEV, "%s state: 0x%08x\n", __func__, cpu_result);
 572
 573 _exit:
 574         ssp_clean_msg(msg);
 575         return cpu_result;
 576 }
 577
 578 unsigned int ssp_get_firmware_rev(struct ssp_data *data)
 579 {
 580         int ret;
 581         __le32 result;
 582
 583         struct ssp_msg *msg = ssp_create_msg(SSP_MSG2SSP_AP_FIRMWARE_REV, 4,
 584                                              SSP_AP2HUB_READ, 0);
 585         if (!msg)
 586                 return SSP_INVALID_REVISION;
 587
 588         ret = ssp_spi_sync(data, msg, 1000);
 589         if (ret < 0) {
 590                 dev_err(SSP_DEV, "%s - transfer fail %d\n", __func__, ret);
 591                 ret = SSP_INVALID_REVISION;
 592                 goto _exit;
 593         }
 594
 595         ssp_get_buffer(msg, 0, &result, 4);
 596         ret = le32_to_cpu(result);
 597
 598 _exit:
 599         ssp_clean_msg(msg);
 600         return ret;
 601 }