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