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                 size = I2C_SMBUS_BLOCK_DATA;
 700                 /* fallthrough */
 701         case I2C_SMBUS_BLOCK_DATA:
 702                 if (I2C_SMBUS_READ == read_write) {
 703                         count = cp2112_write_read_req(buf, addr,
 704                                                       I2C_SMBUS_BLOCK_MAX,
 705                                                       command, NULL, 0);
 706                 } else {
 707                         count = cp2112_write_req(buf, addr, command,
 708                                                  data->block,
 709                                                  data->block[0] + 1);
 710                 }
 711                 break;
 712         case I2C_SMBUS_BLOCK_PROC_CALL:
 713                 size = I2C_SMBUS_BLOCK_DATA;
 714                 read_write = I2C_SMBUS_READ;
 715
 716                 count = cp2112_write_read_req(buf, addr, I2C_SMBUS_BLOCK_MAX,
 717                                               command, data->block,
 718                                               data->block[0] + 1);
 719                 break;
 720         default:
 721                 hid_warn(hdev, "Unsupported transaction %d\n", size);
 722                 return -EOPNOTSUPP;
 723         }
 724
 725         if (count < 0)
 726                 return count;
 727
 728         ret = hid_hw_power(hdev, PM_HINT_FULLON);
 729         if (ret < 0) {
 730                 hid_err(hdev, "power management error: %d\n", ret);
 731                 return ret;
 732         }
 733
 734         ret = cp2112_hid_output(hdev, buf, count, HID_OUTPUT_REPORT);
 735         if (ret < 0) {
 736                 hid_warn(hdev, "Error starting transaction: %d\n", ret);
 737                 goto power_normal;
 738         }
 739
 740         for (retries = 0; retries < XFER_STATUS_RETRIES; ++retries) {
 741                 ret = cp2112_xfer_status(dev);
 742                 if (-EBUSY == ret)
 743                         continue;
 744                 if (ret < 0)
 745                         goto power_normal;
 746                 break;
 747         }
 748
 749         if (XFER_STATUS_RETRIES <= retries) {
 750                 hid_warn(hdev, "Transfer timed out, cancelling.\n");
 751                 buf[0] = CP2112_CANCEL_TRANSFER;
 752                 buf[1] = 0x01;
 753
 754                 ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
 755                 if (ret < 0)
 756                         hid_warn(hdev, "Error cancelling transaction: %d\n",
 757                                  ret);
 758
 759                 ret = -ETIMEDOUT;
 760                 goto power_normal;
 761         }
 762
 763         if (I2C_SMBUS_WRITE == read_write) {
 764                 ret = 0;
 765                 goto power_normal;
 766         }
 767
 768         if (I2C_SMBUS_BLOCK_DATA == size)
 769                 read_length = ret;
 770
 771         ret = cp2112_read(dev, buf, read_length);
 772         if (ret < 0)
 773                 goto power_normal;
 774         if (ret != read_length) {
 775                 hid_warn(hdev, "short read: %d < %zd\n", ret, read_length);
 776                 ret = -EIO;
 777                 goto power_normal;
 778         }
 779
 780         switch (size) {
 781         case I2C_SMBUS_BYTE:
 782         case I2C_SMBUS_BYTE_DATA:
 783                 data->byte = buf[0];
 784                 break;
 785         case I2C_SMBUS_WORD_DATA:
 786                 data->word = le16_to_cpup((__le16 *)buf);
 787                 break;
 788         case I2C_SMBUS_BLOCK_DATA:
 789                 if (read_length > I2C_SMBUS_BLOCK_MAX) {
 790                         ret = -EPROTO;
 791                         goto power_normal;
 792                 }
 793
 794                 memcpy(data->block, buf, read_length);
 795                 break;
 796         }
 797
 798         ret = 0;
 799 power_normal:
 800         hid_hw_power(hdev, PM_HINT_NORMAL);
 801         hid_dbg(hdev, "transfer finished: %d\n", ret);
 802         return ret;
 803 }
 804
 805 static u32 cp2112_functionality(struct i2c_adapter *adap)
 806 {
 807         return I2C_FUNC_I2C |
 808                 I2C_FUNC_SMBUS_BYTE |
 809                 I2C_FUNC_SMBUS_BYTE_DATA |
 810                 I2C_FUNC_SMBUS_WORD_DATA |
 811                 I2C_FUNC_SMBUS_BLOCK_DATA |
 812                 I2C_FUNC_SMBUS_I2C_BLOCK |
 813                 I2C_FUNC_SMBUS_PROC_CALL |
 814                 I2C_FUNC_SMBUS_BLOCK_PROC_CALL;
 815 }
 816
 817 static const struct i2c_algorithm smbus_algorithm = {
 818         .master_xfer    = cp2112_i2c_xfer,
 819         .smbus_xfer     = cp2112_xfer,
 820         .functionality  = cp2112_functionality,
 821 };
 822
 823 static int cp2112_get_usb_config(struct hid_device *hdev,
 824                                  struct cp2112_usb_config_report *cfg)
 825 {
 826         int ret;
 827
 828         ret = cp2112_hid_get(hdev, CP2112_USB_CONFIG, (u8 *)cfg, sizeof(*cfg),
 829                              HID_FEATURE_REPORT);
 830         if (ret != sizeof(*cfg)) {
 831                 hid_err(hdev, "error reading usb config: %d\n", ret);
 832                 if (ret < 0)
 833                         return ret;
 834                 return -EIO;
 835         }
 836
 837         return 0;
 838 }
 839
 840 static int cp2112_set_usb_config(struct hid_device *hdev,
 841                                  struct cp2112_usb_config_report *cfg)
 842 {
 843         int ret;
 844
 845         BUG_ON(cfg->report != CP2112_USB_CONFIG);
 846
 847         ret = cp2112_hid_output(hdev, (u8 *)cfg, sizeof(*cfg),
 848                                 HID_FEATURE_REPORT);
 849         if (ret != sizeof(*cfg)) {
 850                 hid_err(hdev, "error writing usb config: %d\n", ret);
 851                 if (ret < 0)
 852                         return ret;
 853                 return -EIO;
 854         }
 855
 856         return 0;
 857 }
 858
 859 static void chmod_sysfs_attrs(struct hid_device *hdev);
 860
 861 #define CP2112_CONFIG_ATTR(name, store, format, ...) \
 862 static ssize_t name##_store(struct device *kdev, \
 863                             struct device_attribute *attr, const char *buf, \
 864                             size_t count) \
 865 { \
 866         struct hid_device *hdev = to_hid_device(kdev); \
 867         struct cp2112_usb_config_report cfg; \
 868         int ret = cp2112_get_usb_config(hdev, &cfg); \
 869         if (ret) \
 870                 return ret; \
 871         store; \
 872         ret = cp2112_set_usb_config(hdev, &cfg); \
 873         if (ret) \
 874                 return ret; \
 875         chmod_sysfs_attrs(hdev); \
 876         return count; \
 877 } \
 878 static ssize_t name##_show(struct device *kdev, \
 879                            struct device_attribute *attr, char *buf) \
 880 { \
 881         struct hid_device *hdev = to_hid_device(kdev); \
 882         struct cp2112_usb_config_report cfg; \
 883         int ret = cp2112_get_usb_config(hdev, &cfg); \
 884         if (ret) \
 885                 return ret; \
 886         return scnprintf(buf, PAGE_SIZE, format, ##__VA_ARGS__); \
 887 } \
 888 static DEVICE_ATTR_RW(name);
 889
 890 CP2112_CONFIG_ATTR(vendor_id, ({
 891         u16 vid;
 892
 893         if (sscanf(buf, "%hi", &vid) != 1)
 894                 return -EINVAL;
 895
 896         cfg.vid = cpu_to_le16(vid);
 897         cfg.mask = 0x01;
 898 }), "0x%04x\n", le16_to_cpu(cfg.vid));
 899
 900 CP2112_CONFIG_ATTR(product_id, ({
 901         u16 pid;
 902
 903         if (sscanf(buf, "%hi", &pid) != 1)
 904                 return -EINVAL;
 905
 906         cfg.pid = cpu_to_le16(pid);
 907         cfg.mask = 0x02;
 908 }), "0x%04x\n", le16_to_cpu(cfg.pid));
 909
 910 CP2112_CONFIG_ATTR(max_power, ({
 911         int mA;
 912
 913         if (sscanf(buf, "%i", &mA) != 1)
 914                 return -EINVAL;
 915
 916         cfg.max_power = (mA + 1) / 2;
 917         cfg.mask = 0x04;
 918 }), "%u mA\n", cfg.max_power * 2);
 919
 920 CP2112_CONFIG_ATTR(power_mode, ({
 921         if (sscanf(buf, "%hhi", &cfg.power_mode) != 1)
 922                 return -EINVAL;
 923
 924         cfg.mask = 0x08;
 925 }), "%u\n", cfg.power_mode);
 926
 927 CP2112_CONFIG_ATTR(release_version, ({
 928         if (sscanf(buf, "%hhi.%hhi", &cfg.release_major, &cfg.release_minor)
 929             != 2)
 930                 return -EINVAL;
 931
 932         cfg.mask = 0x10;
 933 }), "%u.%u\n", cfg.release_major, cfg.release_minor);
 934
 935 #undef CP2112_CONFIG_ATTR
 936
 937 struct cp2112_pstring_attribute {
 938         struct device_attribute attr;
 939         unsigned char report;
 940 };
 941
 942 static ssize_t pstr_store(struct device *kdev,
 943                           struct device_attribute *kattr, const char *buf,
 944                           size_t count)
 945 {
 946         struct hid_device *hdev = to_hid_device(kdev);
 947         struct cp2112_pstring_attribute *attr =
 948                 container_of(kattr, struct cp2112_pstring_attribute, attr);
 949         struct cp2112_string_report report;
 950         int ret;
 951
 952         memset(&report, 0, sizeof(report));
 953
 954         ret = utf8s_to_utf16s(buf, count, UTF16_LITTLE_ENDIAN,
 955                               report.string, ARRAY_SIZE(report.string));
 956         report.report = attr->report;
 957         report.length = ret * sizeof(report.string[0]) + 2;
 958         report.type = USB_DT_STRING;
 959
 960         ret = cp2112_hid_output(hdev, &report.report, report.length + 1,
 961                                 HID_FEATURE_REPORT);
 962         if (ret != report.length + 1) {
 963                 hid_err(hdev, "error writing %s string: %d\n", kattr->attr.name,
 964                         ret);
 965                 if (ret < 0)
 966                         return ret;
 967                 return -EIO;
 968         }
 969
 970         chmod_sysfs_attrs(hdev);
 971         return count;
 972 }
 973
 974 static ssize_t pstr_show(struct device *kdev,
 975                          struct device_attribute *kattr, char *buf)
 976 {
 977         struct hid_device *hdev = to_hid_device(kdev);
 978         struct cp2112_pstring_attribute *attr =
 979                 container_of(kattr, struct cp2112_pstring_attribute, attr);
 980         struct cp2112_string_report report;
 981         u8 length;
 982         int ret;
 983
 984         ret = cp2112_hid_get(hdev, attr->report, &report.report,
 985                              sizeof(report) - 1, HID_FEATURE_REPORT);
 986         if (ret < 3) {
 987                 hid_err(hdev, "error reading %s string: %d\n", kattr->attr.name,
 988                         ret);
 989                 if (ret < 0)
 990                         return ret;
 991                 return -EIO;
 992         }
 993
 994         if (report.length < 2) {
 995                 hid_err(hdev, "invalid %s string length: %d\n",
 996                         kattr->attr.name, report.length);
 997                 return -EIO;
 998         }
 999
1000         length = report.length > ret - 1 ? ret - 1 : report.length;
1001         length = (length - 2) / sizeof(report.string[0]);
1002         ret = utf16s_to_utf8s(report.string, length, UTF16_LITTLE_ENDIAN, buf,
1003                               PAGE_SIZE - 1);
1004         buf[ret++] = '\n';
1005         return ret;
1006 }
1007
1008 #define CP2112_PSTR_ATTR(name, _report) \
1009 static struct cp2112_pstring_attribute dev_attr_##name = { \
1010         .attr = __ATTR(name, (S_IWUSR | S_IRUGO), pstr_show, pstr_store), \
1011         .report = _report, \
1012 };
1013
1014 CP2112_PSTR_ATTR(manufacturer,  CP2112_MANUFACTURER_STRING);
1015 CP2112_PSTR_ATTR(product,       CP2112_PRODUCT_STRING);
1016 CP2112_PSTR_ATTR(serial,        CP2112_SERIAL_STRING);
1017
1018 #undef CP2112_PSTR_ATTR
1019
1020 static const struct attribute_group cp2112_attr_group = {
1021         .attrs = (struct attribute *[]){
1022                 &dev_attr_vendor_id.attr,
1023                 &dev_attr_product_id.attr,
1024                 &dev_attr_max_power.attr,
1025                 &dev_attr_power_mode.attr,
1026                 &dev_attr_release_version.attr,
1027                 &dev_attr_manufacturer.attr.attr,
1028                 &dev_attr_product.attr.attr,
1029                 &dev_attr_serial.attr.attr,
1030                 NULL
1031         }
1032 };
1033
1034 /* Chmoding our sysfs attributes is simply a way to expose which fields in the
1035  * PROM have already been programmed. We do not depend on this preventing
1036  * writing to these attributes since the CP2112 will simply ignore writes to
1037  * already-programmed fields. This is why there is no sense in fixing this
1038  * racy behaviour.
1039  */
1040 static void chmod_sysfs_attrs(struct hid_device *hdev)
1041 {
1042         struct attribute **attr;
1043         u8 buf[2];
1044         int ret;
1045
1046         ret = cp2112_hid_get(hdev, CP2112_LOCK_BYTE, buf, sizeof(buf),
1047                              HID_FEATURE_REPORT);
1048         if (ret != sizeof(buf)) {
1049                 hid_err(hdev, "error reading lock byte: %d\n", ret);
1050                 return;
1051         }
1052
1053         for (attr = cp2112_attr_group.attrs; *attr; ++attr) {
1054                 umode_t mode = (buf[1] & 1) ? S_IWUSR | S_IRUGO : S_IRUGO;
1055                 ret = sysfs_chmod_file(&hdev->dev.kobj, *attr, mode);
1056                 if (ret < 0)
1057                         hid_err(hdev, "error chmoding sysfs file %s\n",
1058                                 (*attr)->name);
1059                 buf[1] >>= 1;
1060         }
1061 }
1062
1063 static void cp2112_gpio_irq_ack(struct irq_data *d)
1064 {
1065 }
1066
1067 static void cp2112_gpio_irq_mask(struct irq_data *d)
1068 {
1069         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1070         struct cp2112_device *dev = gpiochip_get_data(gc);
1071
1072         __clear_bit(d->hwirq, &dev->irq_mask);
1073 }
1074
1075 static void cp2112_gpio_irq_unmask(struct irq_data *d)
1076 {
1077         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1078         struct cp2112_device *dev = gpiochip_get_data(gc);
1079
1080         __set_bit(d->hwirq, &dev->irq_mask);
1081 }
1082
1083 static void cp2112_gpio_poll_callback(struct work_struct *work)
1084 {
1085         struct cp2112_device *dev = container_of(work, struct cp2112_device,
1086                                                  gpio_poll_worker.work);
1087         struct irq_data *d;
1088         u8 gpio_mask;
1089         u8 virqs = (u8)dev->irq_mask;
1090         u32 irq_type;
1091         int irq, virq, ret;
1092
1093         ret = cp2112_gpio_get_all(&dev->gc);
1094         if (ret == -ENODEV) /* the hardware has been disconnected */
1095                 return;
1096         if (ret < 0)
1097                 goto exit;
1098
1099         gpio_mask = ret;
1100
1101         while (virqs) {
1102                 virq = ffs(virqs) - 1;
1103                 virqs &= ~BIT(virq);
1104
1105                 if (!dev->gc.to_irq)
1106                         break;
1107
1108                 irq = dev->gc.to_irq(&dev->gc, virq);
1109
1110                 d = irq_get_irq_data(irq);
1111                 if (!d)
1112                         continue;
1113
1114                 irq_type = irqd_get_trigger_type(d);
1115
1116                 if (gpio_mask & BIT(virq)) {
1117                         /* Level High */
1118
1119                         if (irq_type & IRQ_TYPE_LEVEL_HIGH)
1120                                 handle_nested_irq(irq);
1121
1122                         if ((irq_type & IRQ_TYPE_EDGE_RISING) &&
1123                             !(dev->gpio_prev_state & BIT(virq)))
1124                                 handle_nested_irq(irq);
1125                 } else {
1126                         /* Level Low */
1127
1128                         if (irq_type & IRQ_TYPE_LEVEL_LOW)
1129                                 handle_nested_irq(irq);
1130
1131                         if ((irq_type & IRQ_TYPE_EDGE_FALLING) &&
1132                             (dev->gpio_prev_state & BIT(virq)))
1133                                 handle_nested_irq(irq);
1134                 }
1135         }
1136
1137         dev->gpio_prev_state = gpio_mask;
1138
1139 exit:
1140         if (dev->gpio_poll)
1141                 schedule_delayed_work(&dev->gpio_poll_worker, 10);
1142 }
1143
1144
1145 static unsigned int cp2112_gpio_irq_startup(struct irq_data *d)
1146 {
1147         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1148         struct cp2112_device *dev = gpiochip_get_data(gc);
1149
1150         INIT_DELAYED_WORK(&dev->gpio_poll_worker, cp2112_gpio_poll_callback);
1151
1152         cp2112_gpio_direction_input(gc, d->hwirq);
1153
1154         if (!dev->gpio_poll) {
1155                 dev->gpio_poll = true;
1156                 schedule_delayed_work(&dev->gpio_poll_worker, 0);
1157         }
1158
1159         cp2112_gpio_irq_unmask(d);
1160         return 0;
1161 }
1162
1163 static void cp2112_gpio_irq_shutdown(struct irq_data *d)
1164 {
1165         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1166         struct cp2112_device *dev = gpiochip_get_data(gc);
1167
1168         cancel_delayed_work_sync(&dev->gpio_poll_worker);
1169 }
1170
1171 static int cp2112_gpio_irq_type(struct irq_data *d, unsigned int type)
1172 {
1173         return 0;
1174 }
1175
1176 static struct irq_chip cp2112_gpio_irqchip = {
1177         .name = "cp2112-gpio",
1178         .irq_startup = cp2112_gpio_irq_startup,
1179         .irq_shutdown = cp2112_gpio_irq_shutdown,
1180         .irq_ack = cp2112_gpio_irq_ack,
1181         .irq_mask = cp2112_gpio_irq_mask,
1182         .irq_unmask = cp2112_gpio_irq_unmask,
1183         .irq_set_type = cp2112_gpio_irq_type,
1184 };
1185
1186 static int __maybe_unused cp2112_allocate_irq(struct cp2112_device *dev,
1187                                               int pin)
1188 {
1189         int ret;
1190
1191         if (dev->desc[pin])
1192                 return -EINVAL;
1193
1194         dev->desc[pin] = gpiochip_request_own_desc(&dev->gc, pin,
1195                                                    "HID/I2C:Event");
1196         if (IS_ERR(dev->desc[pin])) {
1197                 dev_err(dev->gc.parent, "Failed to request GPIO\n");
1198                 return PTR_ERR(dev->desc[pin]);
1199         }
1200
1201         ret = gpiochip_lock_as_irq(&dev->gc, pin);
1202         if (ret) {
1203                 dev_err(dev->gc.parent, "Failed to lock GPIO as interrupt\n");
1204                 goto err_desc;
1205         }
1206
1207         ret = gpiod_to_irq(dev->desc[pin]);
1208         if (ret < 0) {
1209                 dev_err(dev->gc.parent, "Failed to translate GPIO to IRQ\n");
1210                 goto err_lock;
1211         }
1212
1213         return ret;
1214
1215 err_lock:
1216         gpiochip_unlock_as_irq(&dev->gc, pin);
1217 err_desc:
1218         gpiochip_free_own_desc(dev->desc[pin]);
1219         dev->desc[pin] = NULL;
1220         return ret;
1221 }
1222
1223 static int cp2112_probe(struct hid_device *hdev, const struct hid_device_id *id)
1224 {
1225         struct cp2112_device *dev;
1226         u8 buf[3];
1227         struct cp2112_smbus_config_report config;
1228         int ret;
1229
1230         dev = devm_kzalloc(&hdev->dev, sizeof(*dev), GFP_KERNEL);
1231         if (!dev)
1232                 return -ENOMEM;
1233
1234         dev->in_out_buffer = devm_kzalloc(&hdev->dev, CP2112_REPORT_MAX_LENGTH,
1235                                           GFP_KERNEL);
1236         if (!dev->in_out_buffer)
1237                 return -ENOMEM;
1238
1239         mutex_init(&dev->lock);
1240
1241         ret = hid_parse(hdev);
1242         if (ret) {
1243                 hid_err(hdev, "parse failed\n");
1244                 return ret;
1245         }
1246
1247         ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
1248         if (ret) {
1249                 hid_err(hdev, "hw start failed\n");
1250                 return ret;
1251         }
1252
1253         ret = hid_hw_open(hdev);
1254         if (ret) {
1255                 hid_err(hdev, "hw open failed\n");
1256                 goto err_hid_stop;
1257         }
1258
1259         ret = hid_hw_power(hdev, PM_HINT_FULLON);
1260         if (ret < 0) {
1261                 hid_err(hdev, "power management error: %d\n", ret);
1262                 goto err_hid_close;
1263         }
1264
1265         ret = cp2112_hid_get(hdev, CP2112_GET_VERSION_INFO, buf, sizeof(buf),
1266                              HID_FEATURE_REPORT);
1267         if (ret != sizeof(buf)) {
1268                 hid_err(hdev, "error requesting version\n");
1269                 if (ret >= 0)
1270                         ret = -EIO;
1271                 goto err_power_normal;
1272         }
1273
1274         hid_info(hdev, "Part Number: 0x%02X Device Version: 0x%02X\n",
1275                  buf[1], buf[2]);
1276
1277         ret = cp2112_hid_get(hdev, CP2112_SMBUS_CONFIG, (u8 *)&config,
1278                              sizeof(config), HID_FEATURE_REPORT);
1279         if (ret != sizeof(config)) {
1280                 hid_err(hdev, "error requesting SMBus config\n");
1281                 if (ret >= 0)
1282                         ret = -EIO;
1283                 goto err_power_normal;
1284         }
1285
1286         config.retry_time = cpu_to_be16(1);
1287
1288         ret = cp2112_hid_output(hdev, (u8 *)&config, sizeof(config),
1289                                 HID_FEATURE_REPORT);
1290         if (ret != sizeof(config)) {
1291                 hid_err(hdev, "error setting SMBus config\n");
1292                 if (ret >= 0)
1293                         ret = -EIO;
1294                 goto err_power_normal;
1295         }
1296
1297         hid_set_drvdata(hdev, (void *)dev);
1298         dev->hdev               = hdev;
1299         dev->adap.owner         = THIS_MODULE;
1300         dev->adap.class         = I2C_CLASS_HWMON;
1301         dev->adap.algo          = &smbus_algorithm;
1302         dev->adap.algo_data     = dev;
1303         dev->adap.dev.parent    = &hdev->dev;
1304         snprintf(dev->adap.name, sizeof(dev->adap.name),
1305                  "CP2112 SMBus Bridge on hidraw%d",
1306                  ((struct hidraw *)hdev->hidraw)->minor);
1307         dev->hwversion = buf[2];
1308         init_waitqueue_head(&dev->wait);
1309
1310         hid_device_io_start(hdev);
1311         ret = i2c_add_adapter(&dev->adap);
1312         hid_device_io_stop(hdev);
1313
1314         if (ret) {
1315                 hid_err(hdev, "error registering i2c adapter\n");
1316                 goto err_power_normal;
1317         }
1318
1319         hid_dbg(hdev, "adapter registered\n");
1320
1321         dev->gc.label                   = "cp2112_gpio";
1322         dev->gc.direction_input         = cp2112_gpio_direction_input;
1323         dev->gc.direction_output        = cp2112_gpio_direction_output;
1324         dev->gc.set                     = cp2112_gpio_set;
1325         dev->gc.get                     = cp2112_gpio_get;
1326         dev->gc.base                    = -1;
1327         dev->gc.ngpio                   = 8;
1328         dev->gc.can_sleep               = 1;
1329         dev->gc.parent                  = &hdev->dev;
1330
1331         ret = gpiochip_add_data(&dev->gc, dev);
1332         if (ret < 0) {
1333                 hid_err(hdev, "error registering gpio chip\n");
1334                 goto err_free_i2c;
1335         }
1336
1337         ret = sysfs_create_group(&hdev->dev.kobj, &cp2112_attr_group);
1338         if (ret < 0) {
1339                 hid_err(hdev, "error creating sysfs attrs\n");
1340                 goto err_gpiochip_remove;
1341         }
1342
1343         chmod_sysfs_attrs(hdev);
1344         hid_hw_power(hdev, PM_HINT_NORMAL);
1345
1346         ret = gpiochip_irqchip_add(&dev->gc, &cp2112_gpio_irqchip, 0,
1347                                    handle_simple_irq, IRQ_TYPE_NONE);
1348         if (ret) {
1349                 dev_err(dev->gc.parent, "failed to add IRQ chip\n");
1350                 goto err_sysfs_remove;
1351         }
1352
1353         return ret;
1354
1355 err_sysfs_remove:
1356         sysfs_remove_group(&hdev->dev.kobj, &cp2112_attr_group);
1357 err_gpiochip_remove:
1358         gpiochip_remove(&dev->gc);
1359 err_free_i2c:
1360         i2c_del_adapter(&dev->adap);
1361 err_power_normal:
1362         hid_hw_power(hdev, PM_HINT_NORMAL);
1363 err_hid_close:
1364         hid_hw_close(hdev);
1365 err_hid_stop:
1366         hid_hw_stop(hdev);
1367         return ret;
1368 }
1369
1370 static void cp2112_remove(struct hid_device *hdev)
1371 {
1372         struct cp2112_device *dev = hid_get_drvdata(hdev);
1373         int i;
1374
1375         sysfs_remove_group(&hdev->dev.kobj, &cp2112_attr_group);
1376         i2c_del_adapter(&dev->adap);
1377
1378         if (dev->gpio_poll) {
1379                 dev->gpio_poll = false;
1380                 cancel_delayed_work_sync(&dev->gpio_poll_worker);
1381         }
1382
1383         for (i = 0; i < ARRAY_SIZE(dev->desc); i++) {
1384                 gpiochip_unlock_as_irq(&dev->gc, i);
1385                 gpiochip_free_own_desc(dev->desc[i]);
1386         }
1387
1388         gpiochip_remove(&dev->gc);
1389         /* i2c_del_adapter has finished removing all i2c devices from our
1390          * adapter. Well behaved devices should no longer call our cp2112_xfer
1391          * and should have waited for any pending calls to finish. It has also
1392          * waited for device_unregister(&adap->dev) to complete. Therefore we
1393          * can safely free our struct cp2112_device.
1394          */
1395         hid_hw_close(hdev);
1396         hid_hw_stop(hdev);
1397 }
1398
1399 static int cp2112_raw_event(struct hid_device *hdev, struct hid_report *report,
1400                             u8 *data, int size)
1401 {
1402         struct cp2112_device *dev = hid_get_drvdata(hdev);
1403         struct cp2112_xfer_status_report *xfer = (void *)data;
1404
1405         switch (data[0]) {
1406         case CP2112_TRANSFER_STATUS_RESPONSE:
1407                 hid_dbg(hdev, "xfer status: %02x %02x %04x %04x\n",
1408                         xfer->status0, xfer->status1,
1409                         be16_to_cpu(xfer->retries), be16_to_cpu(xfer->length));
1410
1411                 switch (xfer->status0) {
1412                 case STATUS0_IDLE:
1413                         dev->xfer_status = -EAGAIN;
1414                         break;
1415                 case STATUS0_BUSY:
1416                         dev->xfer_status = -EBUSY;
1417                         break;
1418                 case STATUS0_COMPLETE:
1419                         dev->xfer_status = be16_to_cpu(xfer->length);
1420                         break;
1421                 case STATUS0_ERROR:
1422                         switch (xfer->status1) {
1423                         case STATUS1_TIMEOUT_NACK:
1424                         case STATUS1_TIMEOUT_BUS:
1425                                 dev->xfer_status = -ETIMEDOUT;
1426                                 break;
1427                         default:
1428                                 dev->xfer_status = -EIO;
1429                                 break;
1430                         }
1431                         break;
1432                 default:
1433                         dev->xfer_status = -EINVAL;
1434                         break;
1435                 }
1436
1437                 atomic_set(&dev->xfer_avail, 1);
1438                 break;
1439         case CP2112_DATA_READ_RESPONSE:
1440                 hid_dbg(hdev, "read response: %02x %02x\n", data[1], data[2]);
1441
1442                 dev->read_length = data[2];
1443                 if (dev->read_length > sizeof(dev->read_data))
1444                         dev->read_length = sizeof(dev->read_data);
1445
1446                 memcpy(dev->read_data, &data[3], dev->read_length);
1447                 atomic_set(&dev->read_avail, 1);
1448                 break;
1449         default:
1450                 hid_err(hdev, "unknown report\n");
1451
1452                 return 0;
1453         }
1454
1455         wake_up_interruptible(&dev->wait);
1456         return 1;
1457 }
1458
1459 static struct hid_driver cp2112_driver = {
1460         .name           = "cp2112",
1461         .id_table       = cp2112_devices,
1462         .probe          = cp2112_probe,
1463         .remove         = cp2112_remove,
1464         .raw_event      = cp2112_raw_event,
1465 };
1466
1467 module_hid_driver(cp2112_driver);
1468 MODULE_DESCRIPTION("Silicon Labs HID USB to SMBus master bridge");
1469 MODULE_AUTHOR("David Barksdale <dbarksdale@uplogix.com>");
1470 MODULE_LICENSE("GPL");
1471