drivers/hid/hid-cp2112.c

   1 /*
   2  * hid-cp2112.c - Silicon Labs HID USB to SMBus master bridge
   3  * Copyright (c) 2013,2014 Uplogix, Inc.
   4  * David Barksdale <dbarksdale@uplogix.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  */
  15
  16 /*
  17  * The Silicon Labs CP2112 chip is a USB HID device which provides an
  18  * SMBus controller for talking to slave devices and 8 GPIO pins. The
  19  * host communicates with the CP2112 via raw HID reports.
  20  *
  21  * Data Sheet:
  22  *   http://www.silabs.com/Support%20Documents/TechnicalDocs/CP2112.pdf
  23  * Programming Interface Specification:
  24  *   https://www.silabs.com/documents/public/application-notes/an495-cp2112-interface-specification.pdf
  25  */
  26
  27 #include <linux/gpio.h>
  28 #include <linux/gpio/driver.h>
  29 #include <linux/hid.h>
  30 #include <linux/hidraw.h>
  31 #include <linux/i2c.h>
  32 #include <linux/module.h>
  33 #include <linux/nls.h>
  34 #include <linux/usb/ch9.h>
  35 #include "hid-ids.h"
  36
  37 #define CP2112_REPORT_MAX_LENGTH                64
  38 #define CP2112_GPIO_CONFIG_LENGTH               5
  39 #define CP2112_GPIO_GET_LENGTH                  2
  40 #define CP2112_GPIO_SET_LENGTH                  3
  41
  42 enum {
  43         CP2112_GPIO_CONFIG              = 0x02,
  44         CP2112_GPIO_GET                 = 0x03,
  45         CP2112_GPIO_SET                 = 0x04,
  46         CP2112_GET_VERSION_INFO         = 0x05,
  47         CP2112_SMBUS_CONFIG             = 0x06,
  48         CP2112_DATA_READ_REQUEST        = 0x10,
  49         CP2112_DATA_WRITE_READ_REQUEST  = 0x11,
  50         CP2112_DATA_READ_FORCE_SEND     = 0x12,
  51         CP2112_DATA_READ_RESPONSE       = 0x13,
  52         CP2112_DATA_WRITE_REQUEST       = 0x14,
  53         CP2112_TRANSFER_STATUS_REQUEST  = 0x15,
  54         CP2112_TRANSFER_STATUS_RESPONSE = 0x16,
  55         CP2112_CANCEL_TRANSFER          = 0x17,
  56         CP2112_LOCK_BYTE                = 0x20,
  57         CP2112_USB_CONFIG               = 0x21,
  58         CP2112_MANUFACTURER_STRING      = 0x22,
  59         CP2112_PRODUCT_STRING           = 0x23,
  60         CP2112_SERIAL_STRING            = 0x24,
  61 };
  62
  63 enum {
  64         STATUS0_IDLE            = 0x00,
  65         STATUS0_BUSY            = 0x01,
  66         STATUS0_COMPLETE        = 0x02,
  67         STATUS0_ERROR           = 0x03,
  68 };
  69
  70 enum {
  71         STATUS1_TIMEOUT_NACK            = 0x00,
  72         STATUS1_TIMEOUT_BUS             = 0x01,
  73         STATUS1_ARBITRATION_LOST        = 0x02,
  74         STATUS1_READ_INCOMPLETE         = 0x03,
  75         STATUS1_WRITE_INCOMPLETE        = 0x04,
  76         STATUS1_SUCCESS                 = 0x05,
  77 };
  78
  79 struct cp2112_smbus_config_report {
  80         u8 report;              /* CP2112_SMBUS_CONFIG */
  81         __be32 clock_speed;     /* Hz */
  82         u8 device_address;      /* Stored in the upper 7 bits */
  83         u8 auto_send_read;      /* 1 = enabled, 0 = disabled */
  84         __be16 write_timeout;   /* ms, 0 = no timeout */
  85         __be16 read_timeout;    /* ms, 0 = no timeout */
  86         u8 scl_low_timeout;     /* 1 = enabled, 0 = disabled */
  87         __be16 retry_time;      /* # of retries, 0 = no limit */
  88 } __packed;
  89
  90 struct cp2112_usb_config_report {
  91         u8 report;      /* CP2112_USB_CONFIG */
  92         __le16 vid;     /* Vendor ID */
  93         __le16 pid;     /* Product ID */
  94         u8 max_power;   /* Power requested in 2mA units */
  95         u8 power_mode;  /* 0x00 = bus powered
  96                            0x01 = self powered & regulator off
  97                            0x02 = self powered & regulator on */
  98         u8 release_major;
  99         u8 release_minor;
 100         u8 mask;        /* What fields to program */
 101 } __packed;
 102
 103 struct cp2112_read_req_report {
 104         u8 report;      /* CP2112_DATA_READ_REQUEST */
 105         u8 slave_address;
 106         __be16 length;
 107 } __packed;
 108
 109 struct cp2112_write_read_req_report {
 110         u8 report;      /* CP2112_DATA_WRITE_READ_REQUEST */
 111         u8 slave_address;
 112         __be16 length;
 113         u8 target_address_length;
 114         u8 target_address[16];
 115 } __packed;
 116
 117 struct cp2112_write_req_report {
 118         u8 report;      /* CP2112_DATA_WRITE_REQUEST */
 119         u8 slave_address;
 120         u8 length;
 121         u8 data[61];
 122 } __packed;
 123
 124 struct cp2112_force_read_report {
 125         u8 report;      /* CP2112_DATA_READ_FORCE_SEND */
 126         __be16 length;
 127 } __packed;
 128
 129 struct cp2112_xfer_status_report {
 130         u8 report;      /* CP2112_TRANSFER_STATUS_RESPONSE */
 131         u8 status0;     /* STATUS0_* */
 132         u8 status1;     /* STATUS1_* */
 133         __be16 retries;
 134         __be16 length;
 135 } __packed;
 136
 137 struct cp2112_string_report {
 138         u8 dummy;               /* force .string to be aligned */
 139         u8 report;              /* CP2112_*_STRING */
 140         u8 length;              /* length in bytes of everyting after .report */
 141         u8 type;                /* USB_DT_STRING */
 142         wchar_t string[30];     /* UTF16_LITTLE_ENDIAN string */
 143 } __packed;
 144
 145 /* Number of times to request transfer status before giving up waiting for a
 146    transfer to complete. This may need to be changed if SMBUS clock, retries,
 147    or read/write/scl_low timeout settings are changed. */
 148 static const int XFER_STATUS_RETRIES = 10;
 149
 150 /* Time in ms to wait for a CP2112_DATA_READ_RESPONSE or
 151    CP2112_TRANSFER_STATUS_RESPONSE. */
 152 static const int RESPONSE_TIMEOUT = 50;
 153
 154 static const struct hid_device_id cp2112_devices[] = {
 155         { HID_USB_DEVICE(USB_VENDOR_ID_CYGNAL, USB_DEVICE_ID_CYGNAL_CP2112) },
 156         { }
 157 };
 158 MODULE_DEVICE_TABLE(hid, cp2112_devices);
 159
 160 struct cp2112_device {
 161         struct i2c_adapter adap;
 162         struct hid_device *hdev;
 163         wait_queue_head_t wait;
 164         u8 read_data[61];
 165         u8 read_length;
 166         u8 hwversion;
 167         int xfer_status;
 168         atomic_t read_avail;
 169         atomic_t xfer_avail;
 170         struct gpio_chip gc;
 171         u8 *in_out_buffer;
 172         struct mutex lock;
 173
 174         struct gpio_desc *desc[8];
 175         bool gpio_poll;
 176         struct delayed_work gpio_poll_worker;
 177         unsigned long irq_mask;
 178         u8 gpio_prev_state;
 179 };
 180
 181 static int gpio_push_pull = 0xFF;
 182 module_param(gpio_push_pull, int, S_IRUGO | S_IWUSR);
 183 MODULE_PARM_DESC(gpio_push_pull, "GPIO push-pull configuration bitmask");
 184
 185 static int cp2112_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 186 {
 187         struct cp2112_device *dev = gpiochip_get_data(chip);
 188         struct hid_device *hdev = dev->hdev;
 189         u8 *buf = dev->in_out_buffer;
 190         int ret;
 191
 192         mutex_lock(&dev->lock);
 193
 194         ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
 195                                  CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
 196                                  HID_REQ_GET_REPORT);
 197         if (ret != CP2112_GPIO_CONFIG_LENGTH) {
 198                 hid_err(hdev, "error requesting GPIO config: %d\n", ret);
 199                 if (ret >= 0)
 200                         ret = -EIO;
 201                 goto exit;
 202         }
 203
 204         buf[1] &= ~(1 << offset);
 205         buf[2] = gpio_push_pull;
 206
 207         ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
 208                                  CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
 209                                  HID_REQ_SET_REPORT);
 210         if (ret != CP2112_GPIO_CONFIG_LENGTH) {
 211                 hid_err(hdev, "error setting GPIO config: %d\n", ret);
 212                 if (ret >= 0)
 213                         ret = -EIO;
 214                 goto exit;
 215         }
 216
 217         ret = 0;
 218
 219 exit:
 220         mutex_unlock(&dev->lock);
 221         return ret;
 222 }
 223
 224 static void cp2112_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 225 {
 226         struct cp2112_device *dev = gpiochip_get_data(chip);
 227         struct hid_device *hdev = dev->hdev;
 228         u8 *buf = dev->in_out_buffer;
 229         int ret;
 230
 231         mutex_lock(&dev->lock);
 232
 233         buf[0] = CP2112_GPIO_SET;
 234         buf[1] = value ? 0xff : 0;
 235         buf[2] = 1 << offset;
 236
 237         ret = hid_hw_raw_request(hdev, CP2112_GPIO_SET, buf,
 238                                  CP2112_GPIO_SET_LENGTH, HID_FEATURE_REPORT,
 239                                  HID_REQ_SET_REPORT);
 240         if (ret < 0)
 241                 hid_err(hdev, "error setting GPIO values: %d\n", ret);
 242
 243         mutex_unlock(&dev->lock);
 244 }
 245
 246 static int cp2112_gpio_get_all(struct gpio_chip *chip)
 247 {
 248         struct cp2112_device *dev = gpiochip_get_data(chip);
 249         struct hid_device *hdev = dev->hdev;
 250         u8 *buf = dev->in_out_buffer;
 251         int ret;
 252
 253         mutex_lock(&dev->lock);
 254
 255         ret = hid_hw_raw_request(hdev, CP2112_GPIO_GET, buf,
 256                                  CP2112_GPIO_GET_LENGTH, HID_FEATURE_REPORT,
 257                                  HID_REQ_GET_REPORT);
 258         if (ret != CP2112_GPIO_GET_LENGTH) {
 259                 hid_err(hdev, "error requesting GPIO values: %d\n", ret);
 260                 ret = ret < 0 ? ret : -EIO;
 261                 goto exit;
 262         }
 263
 264         ret = buf[1];
 265
 266 exit:
 267         mutex_unlock(&dev->lock);
 268
 269         return ret;
 270 }
 271
 272 static int cp2112_gpio_get(struct gpio_chip *chip, unsigned int offset)
 273 {
 274         int ret;
 275
 276         ret = cp2112_gpio_get_all(chip);
 277         if (ret < 0)
 278                 return ret;
 279
 280         return (ret >> offset) & 1;
 281 }
 282
 283 static int cp2112_gpio_direction_output(struct gpio_chip *chip,
 284                                         unsigned offset, int value)
 285 {
 286         struct cp2112_device *dev = gpiochip_get_data(chip);
 287         struct hid_device *hdev = dev->hdev;
 288         u8 *buf = dev->in_out_buffer;
 289         int ret;
 290
 291         mutex_lock(&dev->lock);
 292
 293         ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
 294                                  CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
 295                                  HID_REQ_GET_REPORT);
 296         if (ret != CP2112_GPIO_CONFIG_LENGTH) {
 297                 hid_err(hdev, "error requesting GPIO config: %d\n", ret);
 298                 goto fail;
 299         }
 300
 301         buf[1] |= 1 << offset;
 302         buf[2] = gpio_push_pull;
 303
 304         ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
 305                                  CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
 306                                  HID_REQ_SET_REPORT);
 307         if (ret < 0) {
 308                 hid_err(hdev, "error setting GPIO config: %d\n", ret);
 309                 goto fail;
 310         }
 311
 312         mutex_unlock(&dev->lock);
 313
 314         /*
 315          * Set gpio value when output direction is already set,
 316          * as specified in AN495, Rev. 0.2, cpt. 4.4
 317          */
 318         cp2112_gpio_set(chip, offset, value);
 319
 320         return 0;
 321
 322 fail:
 323         mutex_unlock(&dev->lock);
 324         return ret < 0 ? ret : -EIO;
 325 }
 326
 327 static int cp2112_hid_get(struct hid_device *hdev, unsigned char report_number,
 328                           u8 *data, size_t count, unsigned char report_type)
 329 {
 330         u8 *buf;
 331         int ret;
 332
 333         buf = kmalloc(count, GFP_KERNEL);
 334         if (!buf)
 335                 return -ENOMEM;
 336
 337         ret = hid_hw_raw_request(hdev, report_number, buf, count,
 338                                        report_type, HID_REQ_GET_REPORT);
 339         memcpy(data, buf, count);
 340         kfree(buf);
 341         return ret;
 342 }
 343
 344 static int cp2112_hid_output(struct hid_device *hdev, u8 *data, size_t count,
 345                              unsigned char report_type)
 346 {
 347         u8 *buf;
 348         int ret;
 349
 350         buf = kmemdup(data, count, GFP_KERNEL);
 351         if (!buf)
 352                 return -ENOMEM;
 353
 354         if (report_type == HID_OUTPUT_REPORT)
 355                 ret = hid_hw_output_report(hdev, buf, count);
 356         else
 357                 ret = hid_hw_raw_request(hdev, buf[0], buf, count, report_type,
 358                                 HID_REQ_SET_REPORT);
 359
 360         kfree(buf);
 361         return ret;
 362 }
 363
 364 static int cp2112_wait(struct cp2112_device *dev, atomic_t *avail)
 365 {
 366         int ret = 0;
 367
 368         /* We have sent either a CP2112_TRANSFER_STATUS_REQUEST or a
 369          * CP2112_DATA_READ_FORCE_SEND and we are waiting for the response to
 370          * come in cp2112_raw_event or timeout. There will only be one of these
 371          * in flight at any one time. The timeout is extremely large and is a
 372          * last resort if the CP2112 has died. If we do timeout we don't expect
 373          * to receive the response which would cause data races, it's not like
 374          * we can do anything about it anyway.
 375          */
 376         ret = wait_event_interruptible_timeout(dev->wait,
 377                 atomic_read(avail), msecs_to_jiffies(RESPONSE_TIMEOUT));
 378         if (-ERESTARTSYS == ret)
 379                 return ret;
 380         if (!ret)
 381                 return -ETIMEDOUT;
 382
 383         atomic_set(avail, 0);
 384         return 0;
 385 }
 386
 387 static int cp2112_xfer_status(struct cp2112_device *dev)
 388 {
 389         struct hid_device *hdev = dev->hdev;
 390         u8 buf[2];
 391         int ret;
 392
 393         buf[0] = CP2112_TRANSFER_STATUS_REQUEST;
 394         buf[1] = 0x01;
 395         atomic_set(&dev->xfer_avail, 0);
 396
 397         ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
 398         if (ret < 0) {
 399                 hid_warn(hdev, "Error requesting status: %d\n", ret);
 400                 return ret;
 401         }
 402
 403         ret = cp2112_wait(dev, &dev->xfer_avail);
 404         if (ret)
 405                 return ret;
 406
 407         return dev->xfer_status;
 408 }
 409
 410 static int cp2112_read(struct cp2112_device *dev, u8 *data, size_t size)
 411 {
 412         struct hid_device *hdev = dev->hdev;
 413         struct cp2112_force_read_report report;
 414         int ret;
 415
 416         if (size > sizeof(dev->read_data))
 417                 size = sizeof(dev->read_data);
 418         report.report = CP2112_DATA_READ_FORCE_SEND;
 419         report.length = cpu_to_be16(size);
 420
 421         atomic_set(&dev->read_avail, 0);
 422
 423         ret = cp2112_hid_output(hdev, &report.report, sizeof(report),
 424                                 HID_OUTPUT_REPORT);
 425         if (ret < 0) {
 426                 hid_warn(hdev, "Error requesting data: %d\n", ret);
 427                 return ret;
 428         }
 429
 430         ret = cp2112_wait(dev, &dev->read_avail);
 431         if (ret)
 432                 return ret;
 433
 434         hid_dbg(hdev, "read %d of %zd bytes requested\n",
 435                 dev->read_length, size);
 436
 437         if (size > dev->read_length)
 438                 size = dev->read_length;
 439
 440         memcpy(data, dev->read_data, size);
 441         return dev->read_length;
 442 }
 443
 444 static int cp2112_read_req(void *buf, u8 slave_address, u16 length)
 445 {
 446         struct cp2112_read_req_report *report = buf;
 447
 448         if (length < 1 || length > 512)
 449                 return -EINVAL;
 450
 451         report->report = CP2112_DATA_READ_REQUEST;
 452         report->slave_address = slave_address << 1;
 453         report->length = cpu_to_be16(length);
 454         return sizeof(*report);
 455 }
 456
 457 static int cp2112_write_read_req(void *buf, u8 slave_address, u16 length,
 458                                  u8 command, u8 *data, u8 data_length)
 459 {
 460         struct cp2112_write_read_req_report *report = buf;
 461
 462         if (length < 1 || length > 512
 463             || data_length > sizeof(report->target_address) - 1)
 464                 return -EINVAL;
 465
 466         report->report = CP2112_DATA_WRITE_READ_REQUEST;
 467         report->slave_address = slave_address << 1;
 468         report->length = cpu_to_be16(length);
 469         report->target_address_length = data_length + 1;
 470         report->target_address[0] = command;
 471         memcpy(&report->target_address[1], data, data_length);
 472         return data_length + 6;
 473 }
 474
 475 static int cp2112_write_req(void *buf, u8 slave_address, u8 command, u8 *data,
 476                             u8 data_length)
 477 {
 478         struct cp2112_write_req_report *report = buf;
 479
 480         if (data_length > sizeof(report->data) - 1)
 481                 return -EINVAL;
 482
 483         report->report = CP2112_DATA_WRITE_REQUEST;
 484         report->slave_address = slave_address << 1;
 485         report->length = data_length + 1;
 486         report->data[0] = command;
 487         memcpy(&report->data[1], data, data_length);
 488         return data_length + 4;
 489 }
 490
 491 static int cp2112_i2c_write_req(void *buf, u8 slave_address, u8 *data,
 492                                 u8 data_length)
 493 {
 494         struct cp2112_write_req_report *report = buf;
 495
 496         if (data_length > sizeof(report->data))
 497                 return -EINVAL;
 498
 499         report->report = CP2112_DATA_WRITE_REQUEST;
 500         report->slave_address = slave_address << 1;
 501         report->length = data_length;
 502         memcpy(report->data, data, data_length);
 503         return data_length + 3;
 504 }
 505
 506 static int cp2112_i2c_write_read_req(void *buf, u8 slave_address,
 507                                      u8 *addr, int addr_length,
 508                                      int read_length)
 509 {
 510         struct cp2112_write_read_req_report *report = buf;
 511
 512         if (read_length < 1 || read_length > 512 ||
 513             addr_length > sizeof(report->target_address))
 514                 return -EINVAL;
 515
 516         report->report = CP2112_DATA_WRITE_READ_REQUEST;
 517         report->slave_address = slave_address << 1;
 518         report->length = cpu_to_be16(read_length);
 519         report->target_address_length = addr_length;
 520         memcpy(report->target_address, addr, addr_length);
 521         return addr_length + 5;
 522 }
 523
 524 static int cp2112_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
 525                            int num)
 526 {
 527         struct cp2112_device *dev = (struct cp2112_device *)adap->algo_data;
 528         struct hid_device *hdev = dev->hdev;
 529         u8 buf[64];
 530         ssize_t count;
 531         ssize_t read_length = 0;
 532         u8 *read_buf = NULL;
 533         unsigned int retries;
 534         int ret;
 535
 536         hid_dbg(hdev, "I2C %d messages\n", num);
 537
 538         if (num == 1) {
 539                 if (msgs->flags & I2C_M_RD) {
 540                         hid_dbg(hdev, "I2C read %#04x len %d\n",
 541                                 msgs->addr, msgs->len);
 542                         read_length = msgs->len;
 543                         read_buf = msgs->buf;
 544                         count = cp2112_read_req(buf, msgs->addr, msgs->len);
 545                 } else {
 546                         hid_dbg(hdev, "I2C write %#04x len %d\n",
 547                                 msgs->addr, msgs->len);
 548                         count = cp2112_i2c_write_req(buf, msgs->addr,
 549                                                      msgs->buf, msgs->len);
 550                 }
 551                 if (count < 0)
 552                         return count;
 553         } else if (dev->hwversion > 1 &&  /* no repeated start in rev 1 */
 554                    num == 2 &&
 555                    msgs[0].addr == msgs[1].addr &&
 556                    !(msgs[0].flags & I2C_M_RD) && (msgs[1].flags & I2C_M_RD)) {
 557                 hid_dbg(hdev, "I2C write-read %#04x wlen %d rlen %d\n",
 558                         msgs[0].addr, msgs[0].len, msgs[1].len);
 559                 read_length = msgs[1].len;
 560                 read_buf = msgs[1].buf;
 561                 count = cp2112_i2c_write_read_req(buf, msgs[0].addr,
 562                                 msgs[0].buf, msgs[0].len, msgs[1].len);
 563                 if (count < 0)
 564                         return count;
 565         } else {
 566                 hid_err(hdev,
 567                         "Multi-message I2C transactions not supported\n");
 568                 return -EOPNOTSUPP;
 569         }
 570
 571         ret = hid_hw_power(hdev, PM_HINT_FULLON);
 572         if (ret < 0) {
 573                 hid_err(hdev, "power management error: %d\n", ret);
 574                 return ret;
 575         }
 576
 577         ret = cp2112_hid_output(hdev, buf, count, HID_OUTPUT_REPORT);
 578         if (ret < 0) {
 579                 hid_warn(hdev, "Error starting transaction: %d\n", ret);
 580                 goto power_normal;
 581         }
 582
 583         for (retries = 0; retries < XFER_STATUS_RETRIES; ++retries) {
 584                 ret = cp2112_xfer_status(dev);
 585                 if (-EBUSY == ret)
 586                         continue;
 587                 if (ret < 0)
 588                         goto power_normal;
 589                 break;
 590         }
 591
 592         if (XFER_STATUS_RETRIES <= retries) {
 593                 hid_warn(hdev, "Transfer timed out, cancelling.\n");
 594                 buf[0] = CP2112_CANCEL_TRANSFER;
 595                 buf[1] = 0x01;
 596
 597                 ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
 598                 if (ret < 0)
 599                         hid_warn(hdev, "Error cancelling transaction: %d\n",
 600                                  ret);
 601
 602                 ret = -ETIMEDOUT;
 603                 goto power_normal;
 604         }
 605
 606         for (count = 0; count < read_length;) {
 607                 ret = cp2112_read(dev, read_buf + count, read_length - count);
 608                 if (ret < 0)
 609                         goto power_normal;
 610                 if (ret == 0) {
 611                         hid_err(hdev, "read returned 0\n");
 612                         ret = -EIO;
 613                         goto power_normal;
 614                 }
 615                 count += ret;
 616                 if (count > read_length) {
 617                         /*
 618                          * The hardware returned too much data.
 619                          * This is mostly harmless because cp2112_read()
 620                          * has a limit check so didn't overrun our
 621                          * buffer.  Nevertheless, we return an error
 622                          * because something is seriously wrong and
 623                          * it shouldn't go unnoticed.
 624                          */
 625                         hid_err(hdev, "long read: %d > %zd\n",
 626                                 ret, read_length - count + ret);
 627                         ret = -EIO;
 628                         goto power_normal;
 629                 }
 630         }
 631
 632         /* return the number of transferred messages */
 633         ret = num;
 634
 635 power_normal:
 636         hid_hw_power(hdev, PM_HINT_NORMAL);
 637         hid_dbg(hdev, "I2C transfer finished: %d\n", ret);
 638         return ret;
 639 }
 640
 641 static int cp2112_xfer(struct i2c_adapter *adap, u16 addr,
 642                        unsigned short flags, char read_write, u8 command,
 643                        int size, union i2c_smbus_data *data)
 644 {
 645         struct cp2112_device *dev = (struct cp2112_device *)adap->algo_data;
 646         struct hid_device *hdev = dev->hdev;
 647         u8 buf[64];
 648         __le16 word;
 649         ssize_t count;
 650         size_t read_length = 0;
 651         unsigned int retries;
 652         int ret;
 653
 654         hid_dbg(hdev, "%s addr 0x%x flags 0x%x cmd 0x%x size %d\n",
 655                 read_write == I2C_SMBUS_WRITE ? "write" : "read",
 656                 addr, flags, command, size);
 657
 658         switch (size) {
 659         case I2C_SMBUS_BYTE:
 660                 read_length = 1;
 661
 662                 if (I2C_SMBUS_READ == read_write)
 663                         count = cp2112_read_req(buf, addr, read_length);
 664                 else
 665                         count = cp2112_write_req(buf, addr, command, NULL,
 666                                                  0);
 667                 break;
 668         case I2C_SMBUS_BYTE_DATA:
 669                 read_length = 1;
 670
 671                 if (I2C_SMBUS_READ == read_write)
 672                         count = cp2112_write_read_req(buf, addr, read_length,
 673                                                       command, NULL, 0);
 674                 else
 675                         count = cp2112_write_req(buf, addr, command,
 676                                                  &data->byte, 1);
 677                 break;
 678         case I2C_SMBUS_WORD_DATA:
 679                 read_length = 2;
 680                 word = cpu_to_le16(data->word);
 681
 682                 if (I2C_SMBUS_READ == read_write)
 683                         count = cp2112_write_read_req(buf, addr, read_length,
 684                                                       command, NULL, 0);
 685                 else
 686                         count = cp2112_write_req(buf, addr, command,
 687                                                  (u8 *)&word, 2);
 688                 break;
 689         case I2C_SMBUS_PROC_CALL:
 690                 size = I2C_SMBUS_WORD_DATA;
 691                 read_write = I2C_SMBUS_READ;
 692                 read_length = 2;
 693                 word = cpu_to_le16(data->word);
 694
 695                 count = cp2112_write_read_req(buf, addr, read_length, command,
 696                                               (u8 *)&word, 2);
 697                 break;
 698         case I2C_SMBUS_I2C_BLOCK_DATA:
 699                 if (read_write == I2C_SMBUS_READ) {
 700                         read_length = data->block[0];
 701                         count = cp2112_write_read_req(buf, addr, read_length,
 702                                                       command, NULL, 0);
 703                 } else {
 704                         count = cp2112_write_req(buf, addr, command,
 705                                                  data->block + 1,
 706                                                  data->block[0]);
 707                 }
 708                 break;
 709         case I2C_SMBUS_BLOCK_DATA:
 710                 if (I2C_SMBUS_READ == read_write) {
 711                         count = cp2112_write_read_req(buf, addr,
 712                                                       I2C_SMBUS_BLOCK_MAX,
 713                                                       command, NULL, 0);
 714                 } else {
 715                         count = cp2112_write_req(buf, addr, command,
 716                                                  data->block,
 717                                                  data->block[0] + 1);
 718                 }
 719                 break;
 720         case I2C_SMBUS_BLOCK_PROC_CALL:
 721                 size = I2C_SMBUS_BLOCK_DATA;
 722                 read_write = I2C_SMBUS_READ;
 723
 724                 count = cp2112_write_read_req(buf, addr, I2C_SMBUS_BLOCK_MAX,
 725                                               command, data->block,
 726                                               data->block[0] + 1);
 727                 break;
 728         default:
 729                 hid_warn(hdev, "Unsupported transaction %d\n", size);
 730                 return -EOPNOTSUPP;
 731         }
 732
 733         if (count < 0)
 734                 return count;
 735
 736         ret = hid_hw_power(hdev, PM_HINT_FULLON);
 737         if (ret < 0) {
 738                 hid_err(hdev, "power management error: %d\n", ret);
 739                 return ret;
 740         }
 741
 742         ret = cp2112_hid_output(hdev, buf, count, HID_OUTPUT_REPORT);
 743         if (ret < 0) {
 744                 hid_warn(hdev, "Error starting transaction: %d\n", ret);
 745                 goto power_normal;
 746         }
 747
 748         for (retries = 0; retries < XFER_STATUS_RETRIES; ++retries) {
 749                 ret = cp2112_xfer_status(dev);
 750                 if (-EBUSY == ret)
 751                         continue;
 752                 if (ret < 0)
 753                         goto power_normal;
 754                 break;
 755         }
 756
 757         if (XFER_STATUS_RETRIES <= retries) {
 758                 hid_warn(hdev, "Transfer timed out, cancelling.\n");
 759                 buf[0] = CP2112_CANCEL_TRANSFER;
 760                 buf[1] = 0x01;
 761
 762                 ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
 763                 if (ret < 0)
 764                         hid_warn(hdev, "Error cancelling transaction: %d\n",
 765                                  ret);
 766
 767                 ret = -ETIMEDOUT;
 768                 goto power_normal;
 769         }
 770
 771         if (I2C_SMBUS_WRITE == read_write) {
 772                 ret = 0;
 773                 goto power_normal;
 774         }
 775
 776         if (I2C_SMBUS_BLOCK_DATA == size)
 777                 read_length = ret;
 778
 779         ret = cp2112_read(dev, buf, read_length);
 780         if (ret < 0)
 781                 goto power_normal;
 782         if (ret != read_length) {
 783                 hid_warn(hdev, "short read: %d < %zd\n", ret, read_length);
 784                 ret = -EIO;
 785                 goto power_normal;
 786         }
 787
 788         switch (size) {
 789         case I2C_SMBUS_BYTE:
 790         case I2C_SMBUS_BYTE_DATA:
 791                 data->byte = buf[0];
 792                 break;
 793         case I2C_SMBUS_WORD_DATA:
 794                 data->word = le16_to_cpup((__le16 *)buf);
 795                 break;
 796         case I2C_SMBUS_I2C_BLOCK_DATA:
 797                 memcpy(data->block + 1, buf, read_length);
 798                 break;
 799         case I2C_SMBUS_BLOCK_DATA:
 800                 if (read_length > I2C_SMBUS_BLOCK_MAX) {
 801                         ret = -EPROTO;
 802                         goto power_normal;
 803                 }
 804
 805                 memcpy(data->block, buf, read_length);
 806                 break;
 807         }
 808
 809         ret = 0;
 810 power_normal:
 811         hid_hw_power(hdev, PM_HINT_NORMAL);
 812         hid_dbg(hdev, "transfer finished: %d\n", ret);
 813         return ret;
 814 }
 815
 816 static u32 cp2112_functionality(struct i2c_adapter *adap)
 817 {
 818         return I2C_FUNC_I2C |
 819                 I2C_FUNC_SMBUS_BYTE |
 820                 I2C_FUNC_SMBUS_BYTE_DATA |
 821                 I2C_FUNC_SMBUS_WORD_DATA |
 822                 I2C_FUNC_SMBUS_BLOCK_DATA |
 823                 I2C_FUNC_SMBUS_I2C_BLOCK |
 824                 I2C_FUNC_SMBUS_PROC_CALL |
 825                 I2C_FUNC_SMBUS_BLOCK_PROC_CALL;
 826 }
 827
 828 static const struct i2c_algorithm smbus_algorithm = {
 829         .master_xfer    = cp2112_i2c_xfer,
 830         .smbus_xfer     = cp2112_xfer,
 831         .functionality  = cp2112_functionality,
 832 };
 833
 834 static int cp2112_get_usb_config(struct hid_device *hdev,
 835                                  struct cp2112_usb_config_report *cfg)
 836 {
 837         int ret;
 838
 839         ret = cp2112_hid_get(hdev, CP2112_USB_CONFIG, (u8 *)cfg, sizeof(*cfg),
 840                              HID_FEATURE_REPORT);
 841         if (ret != sizeof(*cfg)) {
 842                 hid_err(hdev, "error reading usb config: %d\n", ret);
 843                 if (ret < 0)
 844                         return ret;
 845                 return -EIO;
 846         }
 847
 848         return 0;
 849 }
 850
 851 static int cp2112_set_usb_config(struct hid_device *hdev,
 852                                  struct cp2112_usb_config_report *cfg)
 853 {
 854         int ret;
 855
 856         BUG_ON(cfg->report != CP2112_USB_CONFIG);
 857
 858         ret = cp2112_hid_output(hdev, (u8 *)cfg, sizeof(*cfg),
 859                                 HID_FEATURE_REPORT);
 860         if (ret != sizeof(*cfg)) {
 861                 hid_err(hdev, "error writing usb config: %d\n", ret);
 862                 if (ret < 0)
 863                         return ret;
 864                 return -EIO;
 865         }
 866
 867         return 0;
 868 }
 869
 870 static void chmod_sysfs_attrs(struct hid_device *hdev);
 871
 872 #define CP2112_CONFIG_ATTR(name, store, format, ...) \
 873 static ssize_t name##_store(struct device *kdev, \
 874                             struct device_attribute *attr, const char *buf, \
 875                             size_t count) \
 876 { \
 877         struct hid_device *hdev = to_hid_device(kdev); \
 878         struct cp2112_usb_config_report cfg; \
 879         int ret = cp2112_get_usb_config(hdev, &cfg); \
 880         if (ret) \
 881                 return ret; \
 882         store; \
 883         ret = cp2112_set_usb_config(hdev, &cfg); \
 884         if (ret) \
 885                 return ret; \
 886         chmod_sysfs_attrs(hdev); \
 887         return count; \
 888 } \
 889 static ssize_t name##_show(struct device *kdev, \
 890                            struct device_attribute *attr, char *buf) \
 891 { \
 892         struct hid_device *hdev = to_hid_device(kdev); \
 893         struct cp2112_usb_config_report cfg; \
 894         int ret = cp2112_get_usb_config(hdev, &cfg); \
 895         if (ret) \
 896                 return ret; \
 897         return scnprintf(buf, PAGE_SIZE, format, ##__VA_ARGS__); \
 898 } \
 899 static DEVICE_ATTR_RW(name);
 900
 901 CP2112_CONFIG_ATTR(vendor_id, ({
 902         u16 vid;
 903
 904         if (sscanf(buf, "%hi", &vid) != 1)
 905                 return -EINVAL;
 906
 907         cfg.vid = cpu_to_le16(vid);
 908         cfg.mask = 0x01;
 909 }), "0x%04x\n", le16_to_cpu(cfg.vid));
 910
 911 CP2112_CONFIG_ATTR(product_id, ({
 912         u16 pid;
 913
 914         if (sscanf(buf, "%hi", &pid) != 1)
 915                 return -EINVAL;
 916
 917         cfg.pid = cpu_to_le16(pid);
 918         cfg.mask = 0x02;
 919 }), "0x%04x\n", le16_to_cpu(cfg.pid));
 920
 921 CP2112_CONFIG_ATTR(max_power, ({
 922         int mA;
 923
 924         if (sscanf(buf, "%i", &mA) != 1)
 925                 return -EINVAL;
 926
 927         cfg.max_power = (mA + 1) / 2;
 928         cfg.mask = 0x04;
 929 }), "%u mA\n", cfg.max_power * 2);
 930
 931 CP2112_CONFIG_ATTR(power_mode, ({
 932         if (sscanf(buf, "%hhi", &cfg.power_mode) != 1)
 933                 return -EINVAL;
 934
 935         cfg.mask = 0x08;
 936 }), "%u\n", cfg.power_mode);
 937
 938 CP2112_CONFIG_ATTR(release_version, ({
 939         if (sscanf(buf, "%hhi.%hhi", &cfg.release_major, &cfg.release_minor)
 940             != 2)
 941                 return -EINVAL;
 942
 943         cfg.mask = 0x10;
 944 }), "%u.%u\n", cfg.release_major, cfg.release_minor);
 945
 946 #undef CP2112_CONFIG_ATTR
 947
 948 struct cp2112_pstring_attribute {
 949         struct device_attribute attr;
 950         unsigned char report;
 951 };
 952
 953 static ssize_t pstr_store(struct device *kdev,
 954                           struct device_attribute *kattr, const char *buf,
 955                           size_t count)
 956 {
 957         struct hid_device *hdev = to_hid_device(kdev);
 958         struct cp2112_pstring_attribute *attr =
 959                 container_of(kattr, struct cp2112_pstring_attribute, attr);
 960         struct cp2112_string_report report;
 961         int ret;
 962
 963         memset(&report, 0, sizeof(report));
 964
 965         ret = utf8s_to_utf16s(buf, count, UTF16_LITTLE_ENDIAN,
 966                               report.string, ARRAY_SIZE(report.string));
 967         report.report = attr->report;
 968         report.length = ret * sizeof(report.string[0]) + 2;
 969         report.type = USB_DT_STRING;
 970
 971         ret = cp2112_hid_output(hdev, &report.report, report.length + 1,
 972                                 HID_FEATURE_REPORT);
 973         if (ret != report.length + 1) {
 974                 hid_err(hdev, "error writing %s string: %d\n", kattr->attr.name,
 975                         ret);
 976                 if (ret < 0)
 977                         return ret;
 978                 return -EIO;
 979         }
 980
 981         chmod_sysfs_attrs(hdev);
 982         return count;
 983 }
 984
 985 static ssize_t pstr_show(struct device *kdev,
 986                          struct device_attribute *kattr, char *buf)
 987 {
 988         struct hid_device *hdev = to_hid_device(kdev);
 989         struct cp2112_pstring_attribute *attr =
 990                 container_of(kattr, struct cp2112_pstring_attribute, attr);
 991         struct cp2112_string_report report;
 992         u8 length;
 993         int ret;
 994
 995         ret = cp2112_hid_get(hdev, attr->report, &report.report,
 996                              sizeof(report) - 1, HID_FEATURE_REPORT);
 997         if (ret < 3) {
 998                 hid_err(hdev, "error reading %s string: %d\n", kattr->attr.name,
 999                         ret);
1000                 if (ret < 0)
1001                         return ret;
1002                 return -EIO;
1003         }
1004
1005         if (report.length < 2) {
1006                 hid_err(hdev, "invalid %s string length: %d\n",
1007                         kattr->attr.name, report.length);
1008                 return -EIO;
1009         }
1010
1011         length = report.length > ret - 1 ? ret - 1 : report.length;
1012         length = (length - 2) / sizeof(report.string[0]);
1013         ret = utf16s_to_utf8s(report.string, length, UTF16_LITTLE_ENDIAN, buf,
1014                               PAGE_SIZE - 1);
1015         buf[ret++] = '\n';
1016         return ret;
1017 }
1018
1019 #define CP2112_PSTR_ATTR(name, _report) \
1020 static struct cp2112_pstring_attribute dev_attr_##name = { \
1021         .attr = __ATTR(name, (S_IWUSR | S_IRUGO), pstr_show, pstr_store), \
1022         .report = _report, \
1023 };
1024
1025 CP2112_PSTR_ATTR(manufacturer,  CP2112_MANUFACTURER_STRING);
1026 CP2112_PSTR_ATTR(product,       CP2112_PRODUCT_STRING);
1027 CP2112_PSTR_ATTR(serial,        CP2112_SERIAL_STRING);
1028
1029 #undef CP2112_PSTR_ATTR
1030
1031 static const struct attribute_group cp2112_attr_group = {
1032         .attrs = (struct attribute *[]){
1033                 &dev_attr_vendor_id.attr,
1034                 &dev_attr_product_id.attr,
1035                 &dev_attr_max_power.attr,
1036                 &dev_attr_power_mode.attr,
1037                 &dev_attr_release_version.attr,
1038                 &dev_attr_manufacturer.attr.attr,
1039                 &dev_attr_product.attr.attr,
1040                 &dev_attr_serial.attr.attr,
1041                 NULL
1042         }
1043 };
1044
1045 /* Chmoding our sysfs attributes is simply a way to expose which fields in the
1046  * PROM have already been programmed. We do not depend on this preventing
1047  * writing to these attributes since the CP2112 will simply ignore writes to
1048  * already-programmed fields. This is why there is no sense in fixing this
1049  * racy behaviour.
1050  */
1051 static void chmod_sysfs_attrs(struct hid_device *hdev)
1052 {
1053         struct attribute **attr;
1054         u8 buf[2];
1055         int ret;
1056
1057         ret = cp2112_hid_get(hdev, CP2112_LOCK_BYTE, buf, sizeof(buf),
1058                              HID_FEATURE_REPORT);
1059         if (ret != sizeof(buf)) {
1060                 hid_err(hdev, "error reading lock byte: %d\n", ret);
1061                 return;
1062         }
1063
1064         for (attr = cp2112_attr_group.attrs; *attr; ++attr) {
1065                 umode_t mode = (buf[1] & 1) ? S_IWUSR | S_IRUGO : S_IRUGO;
1066                 ret = sysfs_chmod_file(&hdev->dev.kobj, *attr, mode);
1067                 if (ret < 0)
1068                         hid_err(hdev, "error chmoding sysfs file %s\n",
1069                                 (*attr)->name);
1070                 buf[1] >>= 1;
1071         }
1072 }
1073
1074 static void cp2112_gpio_irq_ack(struct irq_data *d)
1075 {
1076 }
1077
1078 static void cp2112_gpio_irq_mask(struct irq_data *d)
1079 {
1080         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1081         struct cp2112_device *dev = gpiochip_get_data(gc);
1082
1083         __clear_bit(d->hwirq, &dev->irq_mask);
1084 }
1085
1086 static void cp2112_gpio_irq_unmask(struct irq_data *d)
1087 {
1088         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1089         struct cp2112_device *dev = gpiochip_get_data(gc);
1090
1091         __set_bit(d->hwirq, &dev->irq_mask);
1092 }
1093
1094 static void cp2112_gpio_poll_callback(struct work_struct *work)
1095 {
1096         struct cp2112_device *dev = container_of(work, struct cp2112_device,
1097                                                  gpio_poll_worker.work);
1098         struct irq_data *d;
1099         u8 gpio_mask;
1100         u8 virqs = (u8)dev->irq_mask;
1101         u32 irq_type;
1102         int irq, virq, ret;
1103
1104         ret = cp2112_gpio_get_all(&dev->gc);
1105         if (ret == -ENODEV) /* the hardware has been disconnected */
1106                 return;
1107         if (ret < 0)
1108                 goto exit;
1109
1110         gpio_mask = ret;
1111
1112         while (virqs) {
1113                 virq = ffs(virqs) - 1;
1114                 virqs &= ~BIT(virq);
1115
1116                 if (!dev->gc.to_irq)
1117                         break;
1118
1119                 irq = dev->gc.to_irq(&dev->gc, virq);
1120
1121                 d = irq_get_irq_data(irq);
1122                 if (!d)
1123                         continue;
1124
1125                 irq_type = irqd_get_trigger_type(d);
1126
1127                 if (gpio_mask & BIT(virq)) {
1128                         /* Level High */
1129
1130                         if (irq_type & IRQ_TYPE_LEVEL_HIGH)
1131                                 handle_nested_irq(irq);
1132
1133                         if ((irq_type & IRQ_TYPE_EDGE_RISING) &&
1134                             !(dev->gpio_prev_state & BIT(virq)))
1135                                 handle_nested_irq(irq);
1136                 } else {
1137                         /* Level Low */
1138
1139                         if (irq_type & IRQ_TYPE_LEVEL_LOW)
1140                                 handle_nested_irq(irq);
1141
1142                         if ((irq_type & IRQ_TYPE_EDGE_FALLING) &&
1143                             (dev->gpio_prev_state & BIT(virq)))
1144                                 handle_nested_irq(irq);
1145                 }
1146         }
1147
1148         dev->gpio_prev_state = gpio_mask;
1149
1150 exit:
1151         if (dev->gpio_poll)
1152                 schedule_delayed_work(&dev->gpio_poll_worker, 10);
1153 }
1154
1155
1156 static unsigned int cp2112_gpio_irq_startup(struct irq_data *d)
1157 {
1158         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1159         struct cp2112_device *dev = gpiochip_get_data(gc);
1160
1161         INIT_DELAYED_WORK(&dev->gpio_poll_worker, cp2112_gpio_poll_callback);
1162
1163         cp2112_gpio_direction_input(gc, d->hwirq);
1164
1165         if (!dev->gpio_poll) {
1166                 dev->gpio_poll = true;
1167                 schedule_delayed_work(&dev->gpio_poll_worker, 0);
1168         }
1169
1170         cp2112_gpio_irq_unmask(d);
1171         return 0;
1172 }
1173
1174 static void cp2112_gpio_irq_shutdown(struct irq_data *d)
1175 {
1176         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1177         struct cp2112_device *dev = gpiochip_get_data(gc);
1178
1179         cancel_delayed_work_sync(&dev->gpio_poll_worker);
1180 }
1181
1182 static int cp2112_gpio_irq_type(struct irq_data *d, unsigned int type)
1183 {
1184         return 0;
1185 }
1186
1187 static struct irq_chip cp2112_gpio_irqchip = {
1188         .name = "cp2112-gpio",
1189         .irq_startup = cp2112_gpio_irq_startup,
1190         .irq_shutdown = cp2112_gpio_irq_shutdown,
1191         .irq_ack = cp2112_gpio_irq_ack,
1192         .irq_mask = cp2112_gpio_irq_mask,
1193         .irq_unmask = cp2112_gpio_irq_unmask,
1194         .irq_set_type = cp2112_gpio_irq_type,
1195 };
1196
1197 static int __maybe_unused cp2112_allocate_irq(struct cp2112_device *dev,
1198                                               int pin)
1199 {
1200         int ret;
1201
1202         if (dev->desc[pin])
1203                 return -EINVAL;
1204
1205         dev->desc[pin] = gpiochip_request_own_desc(&dev->gc, pin,
1206                                                    "HID/I2C:Event");
1207         if (IS_ERR(dev->desc[pin])) {
1208                 dev_err(dev->gc.parent, "Failed to request GPIO\n");
1209                 return PTR_ERR(dev->desc[pin]);
1210         }
1211
1212         ret = gpiochip_lock_as_irq(&dev->gc, pin);
1213         if (ret) {
1214                 dev_err(dev->gc.parent, "Failed to lock GPIO as interrupt\n");
1215                 goto err_desc;
1216         }
1217
1218         ret = gpiod_to_irq(dev->desc[pin]);
1219         if (ret < 0) {
1220                 dev_err(dev->gc.parent, "Failed to translate GPIO to IRQ\n");
1221                 goto err_lock;
1222         }
1223
1224         return ret;
1225
1226 err_lock:
1227         gpiochip_unlock_as_irq(&dev->gc, pin);
1228 err_desc:
1229         gpiochip_free_own_desc(dev->desc[pin]);
1230         dev->desc[pin] = NULL;
1231         return ret;
1232 }
1233
1234 static int cp2112_probe(struct hid_device *hdev, const struct hid_device_id *id)
1235 {
1236         struct cp2112_device *dev;
1237         u8 buf[3];
1238         struct cp2112_smbus_config_report config;
1239         int ret;
1240
1241         dev = devm_kzalloc(&hdev->dev, sizeof(*dev), GFP_KERNEL);
1242         if (!dev)
1243                 return -ENOMEM;
1244
1245         dev->in_out_buffer = devm_kzalloc(&hdev->dev, CP2112_REPORT_MAX_LENGTH,
1246                                           GFP_KERNEL);
1247         if (!dev->in_out_buffer)
1248                 return -ENOMEM;
1249
1250         mutex_init(&dev->lock);
1251
1252         ret = hid_parse(hdev);
1253         if (ret) {
1254                 hid_err(hdev, "parse failed\n");
1255                 return ret;
1256         }
1257
1258         ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
1259         if (ret) {
1260                 hid_err(hdev, "hw start failed\n");
1261                 return ret;
1262         }
1263
1264         ret = hid_hw_open(hdev);
1265         if (ret) {
1266                 hid_err(hdev, "hw open failed\n");
1267                 goto err_hid_stop;
1268         }
1269
1270         ret = hid_hw_power(hdev, PM_HINT_FULLON);
1271         if (ret < 0) {
1272                 hid_err(hdev, "power management error: %d\n", ret);
1273                 goto err_hid_close;
1274         }
1275
1276         ret = cp2112_hid_get(hdev, CP2112_GET_VERSION_INFO, buf, sizeof(buf),
1277                              HID_FEATURE_REPORT);
1278         if (ret != sizeof(buf)) {
1279                 hid_err(hdev, "error requesting version\n");
1280                 if (ret >= 0)
1281                         ret = -EIO;
1282                 goto err_power_normal;
1283         }
1284
1285         hid_info(hdev, "Part Number: 0x%02X Device Version: 0x%02X\n",
1286                  buf[1], buf[2]);
1287
1288         ret = cp2112_hid_get(hdev, CP2112_SMBUS_CONFIG, (u8 *)&config,
1289                              sizeof(config), HID_FEATURE_REPORT);
1290         if (ret != sizeof(config)) {
1291                 hid_err(hdev, "error requesting SMBus config\n");
1292                 if (ret >= 0)
1293                         ret = -EIO;
1294                 goto err_power_normal;
1295         }
1296
1297         config.retry_time = cpu_to_be16(1);
1298
1299         ret = cp2112_hid_output(hdev, (u8 *)&config, sizeof(config),
1300                                 HID_FEATURE_REPORT);
1301         if (ret != sizeof(config)) {
1302                 hid_err(hdev, "error setting SMBus config\n");
1303                 if (ret >= 0)
1304                         ret = -EIO;
1305                 goto err_power_normal;
1306         }
1307
1308         hid_set_drvdata(hdev, (void *)dev);
1309         dev->hdev               = hdev;
1310         dev->adap.owner         = THIS_MODULE;
1311         dev->adap.class         = I2C_CLASS_HWMON;
1312         dev->adap.algo          = &smbus_algorithm;
1313         dev->adap.algo_data     = dev;
1314         dev->adap.dev.parent    = &hdev->dev;
1315         snprintf(dev->adap.name, sizeof(dev->adap.name),
1316                  "CP2112 SMBus Bridge on hidraw%d",
1317                  ((struct hidraw *)hdev->hidraw)->minor);
1318         dev->hwversion = buf[2];
1319         init_waitqueue_head(&dev->wait);
1320
1321         hid_device_io_start(hdev);
1322         ret = i2c_add_adapter(&dev->adap);
1323         hid_device_io_stop(hdev);
1324
1325         if (ret) {
1326                 hid_err(hdev, "error registering i2c adapter\n");
1327                 goto err_power_normal;
1328         }
1329
1330         hid_dbg(hdev, "adapter registered\n");
1331
1332         dev->gc.label                   = "cp2112_gpio";
1333         dev->gc.direction_input         = cp2112_gpio_direction_input;
1334         dev->gc.direction_output        = cp2112_gpio_direction_output;
1335         dev->gc.set                     = cp2112_gpio_set;
1336         dev->gc.get                     = cp2112_gpio_get;
1337         dev->gc.base                    = -1;
1338         dev->gc.ngpio                   = 8;
1339         dev->gc.can_sleep               = 1;
1340         dev->gc.parent                  = &hdev->dev;
1341
1342         ret = gpiochip_add_data(&dev->gc, dev);
1343         if (ret < 0) {
1344                 hid_err(hdev, "error registering gpio chip\n");
1345                 goto err_free_i2c;
1346         }
1347
1348         ret = sysfs_create_group(&hdev->dev.kobj, &cp2112_attr_group);
1349         if (ret < 0) {
1350                 hid_err(hdev, "error creating sysfs attrs\n");
1351                 goto err_gpiochip_remove;
1352         }
1353
1354         chmod_sysfs_attrs(hdev);
1355         hid_hw_power(hdev, PM_HINT_NORMAL);
1356
1357         ret = gpiochip_irqchip_add(&dev->gc, &cp2112_gpio_irqchip, 0,
1358                                    handle_simple_irq, IRQ_TYPE_NONE);
1359         if (ret) {
1360                 dev_err(dev->gc.parent, "failed to add IRQ chip\n");
1361                 goto err_sysfs_remove;
1362         }
1363
1364         return ret;
1365
1366 err_sysfs_remove:
1367         sysfs_remove_group(&hdev->dev.kobj, &cp2112_attr_group);
1368 err_gpiochip_remove:
1369         gpiochip_remove(&dev->gc);
1370 err_free_i2c:
1371         i2c_del_adapter(&dev->adap);
1372 err_power_normal:
1373         hid_hw_power(hdev, PM_HINT_NORMAL);
1374 err_hid_close:
1375         hid_hw_close(hdev);
1376 err_hid_stop:
1377         hid_hw_stop(hdev);
1378         return ret;
1379 }
1380
1381 static void cp2112_remove(struct hid_device *hdev)
1382 {
1383         struct cp2112_device *dev = hid_get_drvdata(hdev);
1384         int i;
1385
1386         sysfs_remove_group(&hdev->dev.kobj, &cp2112_attr_group);
1387         i2c_del_adapter(&dev->adap);
1388
1389         if (dev->gpio_poll) {
1390                 dev->gpio_poll = false;
1391                 cancel_delayed_work_sync(&dev->gpio_poll_worker);
1392         }
1393
1394         for (i = 0; i < ARRAY_SIZE(dev->desc); i++) {
1395                 gpiochip_unlock_as_irq(&dev->gc, i);
1396                 gpiochip_free_own_desc(dev->desc[i]);
1397         }
1398
1399         gpiochip_remove(&dev->gc);
1400         /* i2c_del_adapter has finished removing all i2c devices from our
1401          * adapter. Well behaved devices should no longer call our cp2112_xfer
1402          * and should have waited for any pending calls to finish. It has also
1403          * waited for device_unregister(&adap->dev) to complete. Therefore we
1404          * can safely free our struct cp2112_device.
1405          */
1406         hid_hw_close(hdev);
1407         hid_hw_stop(hdev);
1408 }
1409
1410 static int cp2112_raw_event(struct hid_device *hdev, struct hid_report *report,
1411                             u8 *data, int size)
1412 {
1413         struct cp2112_device *dev = hid_get_drvdata(hdev);
1414         struct cp2112_xfer_status_report *xfer = (void *)data;
1415
1416         switch (data[0]) {
1417         case CP2112_TRANSFER_STATUS_RESPONSE:
1418                 hid_dbg(hdev, "xfer status: %02x %02x %04x %04x\n",
1419                         xfer->status0, xfer->status1,
1420                         be16_to_cpu(xfer->retries), be16_to_cpu(xfer->length));
1421
1422                 switch (xfer->status0) {
1423                 case STATUS0_IDLE:
1424                         dev->xfer_status = -EAGAIN;
1425                         break;
1426                 case STATUS0_BUSY:
1427                         dev->xfer_status = -EBUSY;
1428                         break;
1429                 case STATUS0_COMPLETE:
1430                         dev->xfer_status = be16_to_cpu(xfer->length);
1431                         break;
1432                 case STATUS0_ERROR:
1433                         switch (xfer->status1) {
1434                         case STATUS1_TIMEOUT_NACK:
1435                         case STATUS1_TIMEOUT_BUS:
1436                                 dev->xfer_status = -ETIMEDOUT;
1437                                 break;
1438                         default:
1439                                 dev->xfer_status = -EIO;
1440                                 break;
1441                         }
1442                         break;
1443                 default:
1444                         dev->xfer_status = -EINVAL;
1445                         break;
1446                 }
1447
1448                 atomic_set(&dev->xfer_avail, 1);
1449                 break;
1450         case CP2112_DATA_READ_RESPONSE:
1451                 hid_dbg(hdev, "read response: %02x %02x\n", data[1], data[2]);
1452
1453                 dev->read_length = data[2];
1454                 if (dev->read_length > sizeof(dev->read_data))
1455                         dev->read_length = sizeof(dev->read_data);
1456
1457                 memcpy(dev->read_data, &data[3], dev->read_length);
1458                 atomic_set(&dev->read_avail, 1);
1459                 break;
1460         default:
1461                 hid_err(hdev, "unknown report\n");
1462
1463                 return 0;
1464         }
1465
1466         wake_up_interruptible(&dev->wait);
1467         return 1;
1468 }
1469
1470 static struct hid_driver cp2112_driver = {
1471         .name           = "cp2112",
1472         .id_table       = cp2112_devices,
1473         .probe          = cp2112_probe,
1474         .remove         = cp2112_remove,
1475         .raw_event      = cp2112_raw_event,
1476 };
1477
1478 module_hid_driver(cp2112_driver);
1479 MODULE_DESCRIPTION("Silicon Labs HID USB to SMBus master bridge");
1480 MODULE_AUTHOR("David Barksdale <dbarksdale@uplogix.com>");
1481 MODULE_LICENSE("GPL");
1482