drivers/iio/accel/mma9551_core.c

   1 /*
   2  * Common code for Freescale MMA955x Intelligent Sensor Platform drivers
   3  * Copyright (c) 2014, Intel Corporation.
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms and conditions of the GNU General Public License,
   7  * version 2, as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  */
  14
  15 #include <linux/module.h>
  16 #include <linux/i2c.h>
  17 #include <linux/delay.h>
  18 #include <linux/iio/iio.h>
  19 #include <linux/pm_runtime.h>
  20 #include "mma9551_core.h"
  21
  22 /* Command masks for mailbox write command */
  23 #define MMA9551_CMD_READ_VERSION_INFO   0x00
  24 #define MMA9551_CMD_READ_CONFIG         0x10
  25 #define MMA9551_CMD_WRITE_CONFIG        0x20
  26 #define MMA9551_CMD_READ_STATUS         0x30
  27
  28 /* Mailbox read command */
  29 #define MMA9551_RESPONSE_COCO           BIT(7)
  30
  31 /* Error-Status codes returned in mailbox read command */
  32 #define MMA9551_MCI_ERROR_NONE                  0x00
  33 #define MMA9551_MCI_ERROR_PARAM                 0x04
  34 #define MMA9551_MCI_INVALID_COUNT               0x19
  35 #define MMA9551_MCI_ERROR_COMMAND               0x1C
  36 #define MMA9551_MCI_ERROR_INVALID_LENGTH        0x21
  37 #define MMA9551_MCI_ERROR_FIFO_BUSY             0x22
  38 #define MMA9551_MCI_ERROR_FIFO_ALLOCATED        0x23
  39 #define MMA9551_MCI_ERROR_FIFO_OVERSIZE         0x24
  40
  41 /* GPIO Application */
  42 #define MMA9551_GPIO_POL_MSB            0x08
  43 #define MMA9551_GPIO_POL_LSB            0x09
  44
  45 /* Sleep/Wake application */
  46 #define MMA9551_SLEEP_CFG               0x06
  47 #define MMA9551_SLEEP_CFG_SNCEN         BIT(0)
  48 #define MMA9551_SLEEP_CFG_FLEEN         BIT(1)
  49 #define MMA9551_SLEEP_CFG_SCHEN         BIT(2)
  50
  51 /* AFE application */
  52 #define MMA9551_AFE_X_ACCEL_REG         0x00
  53 #define MMA9551_AFE_Y_ACCEL_REG         0x02
  54 #define MMA9551_AFE_Z_ACCEL_REG         0x04
  55
  56 /* Reset/Suspend/Clear application */
  57 #define MMA9551_RSC_RESET               0x00
  58 #define MMA9551_RSC_OFFSET(mask)        (3 - (ffs(mask) - 1) / 8)
  59 #define MMA9551_RSC_VAL(mask)           (mask >> (((ffs(mask) - 1) / 8) * 8))
  60
  61 /*
  62  * A response is composed of:
  63  * - control registers: MB0-3
  64  * - data registers: MB4-31
  65  *
  66  * A request is composed of:
  67  * - mbox to write to (always 0)
  68  * - control registers: MB1-4
  69  * - data registers: MB5-31
  70  */
  71 #define MMA9551_MAILBOX_CTRL_REGS       4
  72 #define MMA9551_MAX_MAILBOX_DATA_REGS   28
  73 #define MMA9551_MAILBOX_REGS            32
  74
  75 #define MMA9551_I2C_READ_RETRIES        5
  76 #define MMA9551_I2C_READ_DELAY  50      /* us */
  77
  78 struct mma9551_mbox_request {
  79         u8 start_mbox;          /* Always 0. */
  80         u8 app_id;
  81         /*
  82          * See Section 5.3.1 of the MMA955xL Software Reference Manual.
  83          *
  84          * Bit 7: reserved, always 0
  85          * Bits 6-4: command
  86          * Bits 3-0: upper bits of register offset
  87          */
  88         u8 cmd_off;
  89         u8 lower_off;
  90         u8 nbytes;
  91         u8 buf[MMA9551_MAX_MAILBOX_DATA_REGS - 1];
  92 } __packed;
  93
  94 struct mma9551_mbox_response {
  95         u8 app_id;
  96         /*
  97          * See Section 5.3.3 of the MMA955xL Software Reference Manual.
  98          *
  99          * Bit 7: COCO
 100          * Bits 6-0: Error code.
 101          */
 102         u8 coco_err;
 103         u8 nbytes;
 104         u8 req_bytes;
 105         u8 buf[MMA9551_MAX_MAILBOX_DATA_REGS];
 106 } __packed;
 107
 108 struct mma9551_version_info {
 109         __be32 device_id;
 110         u8 rom_version[2];
 111         u8 fw_version[2];
 112         u8 hw_version[2];
 113         u8 fw_build[2];
 114 };
 115
 116 static int mma9551_transfer(struct i2c_client *client,
 117                             u8 app_id, u8 command, u16 offset,
 118                             u8 *inbytes, int num_inbytes,
 119                             u8 *outbytes, int num_outbytes)
 120 {
 121         struct mma9551_mbox_request req;
 122         struct mma9551_mbox_response rsp;
 123         struct i2c_msg in, out;
 124         u8 req_len, err_code;
 125         int ret, retries;
 126
 127         if (offset >= 1 << 12) {
 128                 dev_err(&client->dev, "register offset too large\n");
 129                 return -EINVAL;
 130         }
 131
 132         req_len = 1 + MMA9551_MAILBOX_CTRL_REGS + num_inbytes;
 133         req.start_mbox = 0;
 134         req.app_id = app_id;
 135         req.cmd_off = command | (offset >> 8);
 136         req.lower_off = offset;
 137
 138         if (command == MMA9551_CMD_WRITE_CONFIG)
 139                 req.nbytes = num_inbytes;
 140         else
 141                 req.nbytes = num_outbytes;
 142         if (num_inbytes)
 143                 memcpy(req.buf, inbytes, num_inbytes);
 144
 145         out.addr = client->addr;
 146         out.flags = 0;
 147         out.len = req_len;
 148         out.buf = (u8 *)&req;
 149
 150         ret = i2c_transfer(client->adapter, &out, 1);
 151         if (ret < 0) {
 152                 dev_err(&client->dev, "i2c write failed\n");
 153                 return ret;
 154         }
 155
 156         retries = MMA9551_I2C_READ_RETRIES;
 157         do {
 158                 udelay(MMA9551_I2C_READ_DELAY);
 159
 160                 in.addr = client->addr;
 161                 in.flags = I2C_M_RD;
 162                 in.len = sizeof(rsp);
 163                 in.buf = (u8 *)&rsp;
 164
 165                 ret = i2c_transfer(client->adapter, &in, 1);
 166                 if (ret < 0) {
 167                         dev_err(&client->dev, "i2c read failed\n");
 168                         return ret;
 169                 }
 170
 171                 if (rsp.coco_err & MMA9551_RESPONSE_COCO)
 172                         break;
 173         } while (--retries > 0);
 174
 175         if (retries == 0) {
 176                 dev_err(&client->dev,
 177                         "timed out while waiting for command response\n");
 178                 return -ETIMEDOUT;
 179         }
 180
 181         if (rsp.app_id != app_id) {
 182                 dev_err(&client->dev,
 183                         "app_id mismatch in response got %02x expected %02x\n",
 184                         rsp.app_id, app_id);
 185                 return -EINVAL;
 186         }
 187
 188         err_code = rsp.coco_err & ~MMA9551_RESPONSE_COCO;
 189         if (err_code != MMA9551_MCI_ERROR_NONE) {
 190                 dev_err(&client->dev, "read returned error %x\n", err_code);
 191                 return -EINVAL;
 192         }
 193
 194         if (rsp.nbytes != rsp.req_bytes) {
 195                 dev_err(&client->dev,
 196                         "output length mismatch got %d expected %d\n",
 197                         rsp.nbytes, rsp.req_bytes);
 198                 return -EINVAL;
 199         }
 200
 201         if (num_outbytes)
 202                 memcpy(outbytes, rsp.buf, num_outbytes);
 203
 204         return 0;
 205 }
 206
 207 /**
 208  * mma9551_read_config_byte() - read 1 configuration byte
 209  * @client:     I2C client
 210  * @app_id:     Application ID
 211  * @reg:        Application register
 212  * @val:        Pointer to store value read
 213  *
 214  * Read one configuration byte from the device using MMA955xL command format.
 215  * Commands to the MMA955xL platform consist of a write followed
 216  * by one or more reads.
 217  *
 218  * Locking note: This function must be called with the device lock held.
 219  * Locking is not handled inside the function. Callers should ensure they
 220  * serialize access to the HW.
 221  *
 222  * Returns: 0 on success, negative value on failure.
 223  */
 224 int mma9551_read_config_byte(struct i2c_client *client, u8 app_id,
 225                              u16 reg, u8 *val)
 226 {
 227         return mma9551_transfer(client, app_id, MMA9551_CMD_READ_CONFIG,
 228                                 reg, NULL, 0, val, 1);
 229 }
 230 EXPORT_SYMBOL(mma9551_read_config_byte);
 231
 232 /**
 233  * mma9551_write_config_byte() - write 1 configuration byte
 234  * @client:     I2C client
 235  * @app_id:     Application ID
 236  * @reg:        Application register
 237  * @val:        Value to write
 238  *
 239  * Write one configuration byte from the device using MMA955xL command format.
 240  * Commands to the MMA955xL platform consist of a write followed by one or
 241  * more reads.
 242  *
 243  * Locking note: This function must be called with the device lock held.
 244  * Locking is not handled inside the function. Callers should ensure they
 245  * serialize access to the HW.
 246  *
 247  * Returns: 0 on success, negative value on failure.
 248  */
 249 int mma9551_write_config_byte(struct i2c_client *client, u8 app_id,
 250                               u16 reg, u8 val)
 251 {
 252         return mma9551_transfer(client, app_id, MMA9551_CMD_WRITE_CONFIG, reg,
 253                                 &val, 1, NULL, 0);
 254 }
 255 EXPORT_SYMBOL(mma9551_write_config_byte);
 256
 257 /**
 258  * mma9551_read_status_byte() - read 1 status byte
 259  * @client:     I2C client
 260  * @app_id:     Application ID
 261  * @reg:        Application register
 262  * @val:        Pointer to store value read
 263  *
 264  * Read one status byte from the device using MMA955xL command format.
 265  * Commands to the MMA955xL platform consist of a write followed by one or
 266  * more reads.
 267  *
 268  * Locking note: This function must be called with the device lock held.
 269  * Locking is not handled inside the function. Callers should ensure they
 270  * serialize access to the HW.
 271  *
 272  * Returns: 0 on success, negative value on failure.
 273  */
 274 int mma9551_read_status_byte(struct i2c_client *client, u8 app_id,
 275                              u16 reg, u8 *val)
 276 {
 277         return mma9551_transfer(client, app_id, MMA9551_CMD_READ_STATUS,
 278                                 reg, NULL, 0, val, 1);
 279 }
 280 EXPORT_SYMBOL(mma9551_read_status_byte);
 281
 282 /**
 283  * mma9551_read_config_word() - read 1 config word
 284  * @client:     I2C client
 285  * @app_id:     Application ID
 286  * @reg:        Application register
 287  * @val:        Pointer to store value read
 288  *
 289  * Read one configuration word from the device using MMA955xL command format.
 290  * Commands to the MMA955xL platform consist of a write followed by one or
 291  * more reads.
 292  *
 293  * Locking note: This function must be called with the device lock held.
 294  * Locking is not handled inside the function. Callers should ensure they
 295  * serialize access to the HW.
 296  *
 297  * Returns: 0 on success, negative value on failure.
 298  */
 299 int mma9551_read_config_word(struct i2c_client *client, u8 app_id,
 300                              u16 reg, u16 *val)
 301 {
 302         int ret;
 303         __be16 v;
 304
 305         ret = mma9551_transfer(client, app_id, MMA9551_CMD_READ_CONFIG,
 306                                reg, NULL, 0, (u8 *)&v, 2);
 307         *val = be16_to_cpu(v);
 308
 309         return ret;
 310 }
 311 EXPORT_SYMBOL(mma9551_read_config_word);
 312
 313 /**
 314  * mma9551_write_config_word() - write 1 config word
 315  * @client:     I2C client
 316  * @app_id:     Application ID
 317  * @reg:        Application register
 318  * @val:        Value to write
 319  *
 320  * Write one configuration word from the device using MMA955xL command format.
 321  * Commands to the MMA955xL platform consist of a write followed by one or
 322  * more reads.
 323  *
 324  * Locking note: This function must be called with the device lock held.
 325  * Locking is not handled inside the function. Callers should ensure they
 326  * serialize access to the HW.
 327  *
 328  * Returns: 0 on success, negative value on failure.
 329  */
 330 int mma9551_write_config_word(struct i2c_client *client, u8 app_id,
 331                               u16 reg, u16 val)
 332 {
 333         __be16 v = cpu_to_be16(val);
 334
 335         return mma9551_transfer(client, app_id, MMA9551_CMD_WRITE_CONFIG, reg,
 336                                 (u8 *)&v, 2, NULL, 0);
 337 }
 338 EXPORT_SYMBOL(mma9551_write_config_word);
 339
 340 /**
 341  * mma9551_read_status_word() - read 1 status word
 342  * @client:     I2C client
 343  * @app_id:     Application ID
 344  * @reg:        Application register
 345  * @val:        Pointer to store value read
 346  *
 347  * Read one status word from the device using MMA955xL command format.
 348  * Commands to the MMA955xL platform consist of a write followed by one or
 349  * more reads.
 350  *
 351  * Locking note: This function must be called with the device lock held.
 352  * Locking is not handled inside the function. Callers should ensure they
 353  * serialize access to the HW.
 354  *
 355  * Returns: 0 on success, negative value on failure.
 356  */
 357 int mma9551_read_status_word(struct i2c_client *client, u8 app_id,
 358                              u16 reg, u16 *val)
 359 {
 360         int ret;
 361         __be16 v;
 362
 363         ret = mma9551_transfer(client, app_id, MMA9551_CMD_READ_STATUS,
 364                                reg, NULL, 0, (u8 *)&v, 2);
 365         *val = be16_to_cpu(v);
 366
 367         return ret;
 368 }
 369 EXPORT_SYMBOL(mma9551_read_status_word);
 370
 371 /**
 372  * mma9551_read_config_words() - read multiple config words
 373  * @client:     I2C client
 374  * @app_id:     Application ID
 375  * @reg:        Application register
 376  * @len:        Length of array to read (in words)
 377  * @buf:        Array of words to read
 378  *
 379  * Read multiple configuration registers (word-sized registers).
 380  *
 381  * Locking note: This function must be called with the device lock held.
 382  * Locking is not handled inside the function. Callers should ensure they
 383  * serialize access to the HW.
 384  *
 385  * Returns: 0 on success, negative value on failure.
 386  */
 387 int mma9551_read_config_words(struct i2c_client *client, u8 app_id,
 388                               u16 reg, u8 len, u16 *buf)
 389 {
 390         int ret, i;
 391         __be16 be_buf[MMA9551_MAX_MAILBOX_DATA_REGS / 2];
 392
 393         if (len > ARRAY_SIZE(be_buf)) {
 394                 dev_err(&client->dev, "Invalid buffer size %d\n", len);
 395                 return -EINVAL;
 396         }
 397
 398         ret = mma9551_transfer(client, app_id, MMA9551_CMD_READ_CONFIG,
 399                                reg, NULL, 0, (u8 *)be_buf, len * sizeof(u16));
 400         if (ret < 0)
 401                 return ret;
 402
 403         for (i = 0; i < len; i++)
 404                 buf[i] = be16_to_cpu(be_buf[i]);
 405
 406         return 0;
 407 }
 408 EXPORT_SYMBOL(mma9551_read_config_words);
 409
 410 /**
 411  * mma9551_read_status_words() - read multiple status words
 412  * @client:     I2C client
 413  * @app_id:     Application ID
 414  * @reg:        Application register
 415  * @len:        Length of array to read (in words)
 416  * @buf:        Array of words to read
 417  *
 418  * Read multiple status registers (word-sized registers).
 419  *
 420  * Locking note: This function must be called with the device lock held.
 421  * Locking is not handled inside the function. Callers should ensure they
 422  * serialize access to the HW.
 423  *
 424  * Returns: 0 on success, negative value on failure.
 425  */
 426 int mma9551_read_status_words(struct i2c_client *client, u8 app_id,
 427                               u16 reg, u8 len, u16 *buf)
 428 {
 429         int ret, i;
 430         __be16 be_buf[MMA9551_MAX_MAILBOX_DATA_REGS / 2];
 431
 432         if (len > ARRAY_SIZE(be_buf)) {
 433                 dev_err(&client->dev, "Invalid buffer size %d\n", len);
 434                 return -EINVAL;
 435         }
 436
 437         ret = mma9551_transfer(client, app_id, MMA9551_CMD_READ_STATUS,
 438                                reg, NULL, 0, (u8 *)be_buf, len * sizeof(u16));
 439         if (ret < 0)
 440                 return ret;
 441
 442         for (i = 0; i < len; i++)
 443                 buf[i] = be16_to_cpu(be_buf[i]);
 444
 445         return 0;
 446 }
 447 EXPORT_SYMBOL(mma9551_read_status_words);
 448
 449 /**
 450  * mma9551_write_config_words() - write multiple config words
 451  * @client:     I2C client
 452  * @app_id:     Application ID
 453  * @reg:        Application register
 454  * @len:        Length of array to write (in words)
 455  * @buf:        Array of words to write
 456  *
 457  * Write multiple configuration registers (word-sized registers).
 458  *
 459  * Locking note: This function must be called with the device lock held.
 460  * Locking is not handled inside the function. Callers should ensure they
 461  * serialize access to the HW.
 462  *
 463  * Returns: 0 on success, negative value on failure.
 464  */
 465 int mma9551_write_config_words(struct i2c_client *client, u8 app_id,
 466                                u16 reg, u8 len, u16 *buf)
 467 {
 468         int i;
 469         __be16 be_buf[(MMA9551_MAX_MAILBOX_DATA_REGS - 1) / 2];
 470
 471         if (len > ARRAY_SIZE(be_buf)) {
 472                 dev_err(&client->dev, "Invalid buffer size %d\n", len);
 473                 return -EINVAL;
 474         }
 475
 476         for (i = 0; i < len; i++)
 477                 be_buf[i] = cpu_to_be16(buf[i]);
 478
 479         return mma9551_transfer(client, app_id, MMA9551_CMD_WRITE_CONFIG,
 480                                 reg, (u8 *)be_buf, len * sizeof(u16), NULL, 0);
 481 }
 482 EXPORT_SYMBOL(mma9551_write_config_words);
 483
 484 /**
 485  * mma9551_update_config_bits() - update bits in register
 486  * @client:     I2C client
 487  * @app_id:     Application ID
 488  * @reg:        Application register
 489  * @mask:       Mask for the bits to update
 490  * @val:        Value of the bits to update
 491  *
 492  * Update bits in the given register using a bit mask.
 493  *
 494  * Locking note: This function must be called with the device lock held.
 495  * Locking is not handled inside the function. Callers should ensure they
 496  * serialize access to the HW.
 497  *
 498  * Returns: 0 on success, negative value on failure.
 499  */
 500 int mma9551_update_config_bits(struct i2c_client *client, u8 app_id,
 501                                u16 reg, u8 mask, u8 val)
 502 {
 503         int ret;
 504         u8 tmp, orig;
 505
 506         ret = mma9551_read_config_byte(client, app_id, reg, &orig);
 507         if (ret < 0)
 508                 return ret;
 509
 510         tmp = orig & ~mask;
 511         tmp |= val & mask;
 512
 513         if (tmp == orig)
 514                 return 0;
 515
 516         return mma9551_write_config_byte(client, app_id, reg, tmp);
 517 }
 518 EXPORT_SYMBOL(mma9551_update_config_bits);
 519
 520 /**
 521  * mma9551_gpio_config() - configure gpio
 522  * @client:     I2C client
 523  * @pin:        GPIO pin to configure
 524  * @app_id:     Application ID
 525  * @bitnum:     Bit number of status register being assigned to the GPIO pin.
 526  * @polarity:   The polarity parameter is described in section 6.2.2, page 66,
 527  *              of the Software Reference Manual.  Basically, polarity=0 means
 528  *              the interrupt line has the same value as the selected bit,
 529  *              while polarity=1 means the line is inverted.
 530  *
 531  * Assign a bit from an application’s status register to a specific GPIO pin.
 532  *
 533  * Locking note: This function must be called with the device lock held.
 534  * Locking is not handled inside the function. Callers should ensure they
 535  * serialize access to the HW.
 536  *
 537  * Returns: 0 on success, negative value on failure.
 538  */
 539 int mma9551_gpio_config(struct i2c_client *client, enum mma9551_gpio_pin pin,
 540                         u8 app_id, u8 bitnum, int polarity)
 541 {
 542         u8 reg, pol_mask, pol_val;
 543         int ret;
 544
 545         if (pin > mma9551_gpio_max) {
 546                 dev_err(&client->dev, "bad GPIO pin\n");
 547                 return -EINVAL;
 548         }
 549
 550         /*
 551          * Pin 6 is configured by regs 0x00 and 0x01, pin 7 by 0x02 and
 552          * 0x03, and so on.
 553          */
 554         reg = pin * 2;
 555
 556         ret = mma9551_write_config_byte(client, MMA9551_APPID_GPIO,
 557                                         reg, app_id);
 558         if (ret < 0) {
 559                 dev_err(&client->dev, "error setting GPIO app_id\n");
 560                 return ret;
 561         }
 562
 563         ret = mma9551_write_config_byte(client, MMA9551_APPID_GPIO,
 564                                         reg + 1, bitnum);
 565         if (ret < 0) {
 566                 dev_err(&client->dev, "error setting GPIO bit number\n");
 567                 return ret;
 568         }
 569
 570         switch (pin) {
 571         case mma9551_gpio6:
 572                 reg = MMA9551_GPIO_POL_LSB;
 573                 pol_mask = 1 << 6;
 574                 break;
 575         case mma9551_gpio7:
 576                 reg = MMA9551_GPIO_POL_LSB;
 577                 pol_mask = 1 << 7;
 578                 break;
 579         case mma9551_gpio8:
 580                 reg = MMA9551_GPIO_POL_MSB;
 581                 pol_mask = 1 << 0;
 582                 break;
 583         case mma9551_gpio9:
 584                 reg = MMA9551_GPIO_POL_MSB;
 585                 pol_mask = 1 << 1;
 586                 break;
 587         }
 588         pol_val = polarity ? pol_mask : 0;
 589
 590         ret = mma9551_update_config_bits(client, MMA9551_APPID_GPIO, reg,
 591                                          pol_mask, pol_val);
 592         if (ret < 0)
 593                 dev_err(&client->dev, "error setting GPIO polarity\n");
 594
 595         return ret;
 596 }
 597 EXPORT_SYMBOL(mma9551_gpio_config);
 598
 599 /**
 600  * mma9551_read_version() - read device version information
 601  * @client:     I2C client
 602  *
 603  * Read version information and print device id and firmware version.
 604  *
 605  * Locking note: This function must be called with the device lock held.
 606  * Locking is not handled inside the function. Callers should ensure they
 607  * serialize access to the HW.
 608  *
 609  * Returns: 0 on success, negative value on failure.
 610  */
 611 int mma9551_read_version(struct i2c_client *client)
 612 {
 613         struct mma9551_version_info info;
 614         int ret;
 615
 616         ret = mma9551_transfer(client, MMA9551_APPID_VERSION, 0x00, 0x00,
 617                                NULL, 0, (u8 *)&info, sizeof(info));
 618         if (ret < 0)
 619                 return ret;
 620
 621         dev_info(&client->dev, "device ID 0x%x, firmware version %02x.%02x\n",
 622                  be32_to_cpu(info.device_id), info.fw_version[0],
 623                  info.fw_version[1]);
 624
 625         return 0;
 626 }
 627 EXPORT_SYMBOL(mma9551_read_version);
 628
 629 /**
 630  * mma9551_set_device_state() - sets HW power mode
 631  * @client:     I2C client
 632  * @enable:     Use true to power on device, false to cause the device
 633  *              to enter sleep.
 634  *
 635  * Set power on/off for device using the Sleep/Wake Application.
 636  * When enable is true, power on chip and enable doze mode.
 637  * When enable is false, enter sleep mode (device remains in the
 638  * lowest-power mode).
 639  *
 640  * Locking note: This function must be called with the device lock held.
 641  * Locking is not handled inside the function. Callers should ensure they
 642  * serialize access to the HW.
 643  *
 644  * Returns: 0 on success, negative value on failure.
 645  */
 646 int mma9551_set_device_state(struct i2c_client *client, bool enable)
 647 {
 648         return mma9551_update_config_bits(client, MMA9551_APPID_SLEEP_WAKE,
 649                                           MMA9551_SLEEP_CFG,
 650                                           MMA9551_SLEEP_CFG_SNCEN |
 651                                           MMA9551_SLEEP_CFG_FLEEN |
 652                                           MMA9551_SLEEP_CFG_SCHEN,
 653                                           enable ? MMA9551_SLEEP_CFG_SCHEN |
 654                                           MMA9551_SLEEP_CFG_FLEEN :
 655                                           MMA9551_SLEEP_CFG_SNCEN);
 656 }
 657 EXPORT_SYMBOL(mma9551_set_device_state);
 658
 659 /**
 660  * mma9551_set_power_state() - sets runtime PM state
 661  * @client:     I2C client
 662  * @on:         Use true to power on device, false to power off
 663  *
 664  * Resume or suspend the device using Runtime PM.
 665  * The device will suspend after the autosuspend delay.
 666  *
 667  * Returns: 0 on success, negative value on failure.
 668  */
 669 int mma9551_set_power_state(struct i2c_client *client, bool on)
 670 {
 671 #ifdef CONFIG_PM
 672         int ret;
 673
 674         if (on)
 675                 ret = pm_runtime_get_sync(&client->dev);
 676         else {
 677                 pm_runtime_mark_last_busy(&client->dev);
 678                 ret = pm_runtime_put_autosuspend(&client->dev);
 679         }
 680
 681         if (ret < 0) {
 682                 dev_err(&client->dev,
 683                         "failed to change power state to %d\n", on);
 684                 if (on)
 685                         pm_runtime_put_noidle(&client->dev);
 686
 687                 return ret;
 688         }
 689 #endif
 690
 691         return 0;
 692 }
 693 EXPORT_SYMBOL(mma9551_set_power_state);
 694
 695 /**
 696  * mma9551_sleep() - sleep
 697  * @freq:       Application frequency
 698  *
 699  * Firmware applications run at a certain frequency on the
 700  * device. Sleep for one application cycle to make sure the
 701  * application had time to run once and initialize set values.
 702  */
 703 void mma9551_sleep(int freq)
 704 {
 705         int sleep_val = 1000 / freq;
 706
 707         if (sleep_val < 20)
 708                 usleep_range(sleep_val * 1000, 20000);
 709         else
 710                 msleep_interruptible(sleep_val);
 711 }
 712 EXPORT_SYMBOL(mma9551_sleep);
 713
 714 /**
 715  * mma9551_read_accel_chan() - read accelerometer channel
 716  * @client:     I2C client
 717  * @chan:       IIO channel
 718  * @val:        Pointer to the accelerometer value read
 719  * @val2:       Unused
 720  *
 721  * Read accelerometer value for the specified channel.
 722  *
 723  * Locking note: This function must be called with the device lock held.
 724  * Locking is not handled inside the function. Callers should ensure they
 725  * serialize access to the HW.
 726  *
 727  * Returns: IIO_VAL_INT on success, negative value on failure.
 728  */
 729 int mma9551_read_accel_chan(struct i2c_client *client,
 730                             const struct iio_chan_spec *chan,
 731                             int *val, int *val2)
 732 {
 733         u16 reg_addr;
 734         s16 raw_accel;
 735         int ret;
 736
 737         switch (chan->channel2) {
 738         case IIO_MOD_X:
 739                 reg_addr = MMA9551_AFE_X_ACCEL_REG;
 740                 break;
 741         case IIO_MOD_Y:
 742                 reg_addr = MMA9551_AFE_Y_ACCEL_REG;
 743                 break;
 744         case IIO_MOD_Z:
 745                 reg_addr = MMA9551_AFE_Z_ACCEL_REG;
 746                 break;
 747         default:
 748                 return -EINVAL;
 749         }
 750
 751         ret = mma9551_set_power_state(client, true);
 752         if (ret < 0)
 753                 return ret;
 754
 755         ret = mma9551_read_status_word(client, MMA9551_APPID_AFE,
 756                                        reg_addr, &raw_accel);
 757         if (ret < 0)
 758                 goto out_poweroff;
 759
 760         *val = raw_accel;
 761
 762         ret = IIO_VAL_INT;
 763
 764 out_poweroff:
 765         mma9551_set_power_state(client, false);
 766         return ret;
 767 }
 768 EXPORT_SYMBOL(mma9551_read_accel_chan);
 769
 770 /**
 771  * mma9551_read_accel_scale() - read accelerometer scale
 772  * @val:        Pointer to the accelerometer scale (int value)
 773  * @val2:       Pointer to the accelerometer scale (micro value)
 774  *
 775  * Read accelerometer scale.
 776  *
 777  * Returns: IIO_VAL_INT_PLUS_MICRO.
 778  */
 779 int mma9551_read_accel_scale(int *val, int *val2)
 780 {
 781         *val = 0;
 782         *val2 = 2440;
 783
 784         return IIO_VAL_INT_PLUS_MICRO;
 785 }
 786 EXPORT_SYMBOL(mma9551_read_accel_scale);
 787
 788 /**
 789  * mma9551_app_reset() - reset application
 790  * @client:     I2C client
 791  * @app_mask:   Application to reset
 792  *
 793  * Reset the given application (using the Reset/Suspend/Clear
 794  * Control Application)
 795  *
 796  * Returns: 0 on success, negative value on failure.
 797  */
 798 int mma9551_app_reset(struct i2c_client *client, u32 app_mask)
 799 {
 800         return mma9551_write_config_byte(client, MMA9551_APPID_RSC,
 801                                          MMA9551_RSC_RESET +
 802                                          MMA9551_RSC_OFFSET(app_mask),
 803                                          MMA9551_RSC_VAL(app_mask));
 804 }
 805 EXPORT_SYMBOL(mma9551_app_reset);
 806
 807 MODULE_AUTHOR("Irina Tirdea <irina.tirdea@intel.com>");
 808 MODULE_AUTHOR("Vlad Dogaru <vlad.dogaru@intel.com>");
 809 MODULE_LICENSE("GPL v2");
 810 MODULE_DESCRIPTION("MMA955xL sensors core");