drivers/hid/hid-cp2112.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * hid-cp2112.c - Silicon Labs HID USB to SMBus master bridge
   4  * Copyright (c) 2013,2014 Uplogix, Inc.
   5  * David Barksdale <dbarksdale@uplogix.com>
   6  */
   7
   8 /*
   9  * The Silicon Labs CP2112 chip is a USB HID device which provides an
  10  * SMBus controller for talking to slave devices and 8 GPIO pins. The
  11  * host communicates with the CP2112 via raw HID reports.
  12  *
  13  * Data Sheet:
  14  *   https://www.silabs.com/Support%20Documents/TechnicalDocs/CP2112.pdf
  15  * Programming Interface Specification:
  16  *   https://www.silabs.com/documents/public/application-notes/an495-cp2112-interface-specification.pdf
  17  */
  18
  19 #include <linux/bitops.h>
  20 #include <linux/gpio/driver.h>
  21 #include <linux/hid.h>
  22 #include <linux/hidraw.h>
  23 #include <linux/i2c.h>
  24 #include <linux/module.h>
  25 #include <linux/nls.h>
  26 #include <linux/string_choices.h>
  27 #include <linux/usb/ch9.h>
  28 #include "hid-ids.h"
  29
  30 #define CP2112_REPORT_MAX_LENGTH                64
  31 #define CP2112_GPIO_CONFIG_LENGTH               5
  32 #define CP2112_GPIO_GET_LENGTH                  2
  33 #define CP2112_GPIO_SET_LENGTH                  3
  34 #define CP2112_GPIO_MAX_GPIO                    8
  35 #define CP2112_GPIO_ALL_GPIO_MASK               GENMASK(7, 0)
  36
  37 enum {
  38         CP2112_GPIO_CONFIG              = 0x02,
  39         CP2112_GPIO_GET                 = 0x03,
  40         CP2112_GPIO_SET                 = 0x04,
  41         CP2112_GET_VERSION_INFO         = 0x05,
  42         CP2112_SMBUS_CONFIG             = 0x06,
  43         CP2112_DATA_READ_REQUEST        = 0x10,
  44         CP2112_DATA_WRITE_READ_REQUEST  = 0x11,
  45         CP2112_DATA_READ_FORCE_SEND     = 0x12,
  46         CP2112_DATA_READ_RESPONSE       = 0x13,
  47         CP2112_DATA_WRITE_REQUEST       = 0x14,
  48         CP2112_TRANSFER_STATUS_REQUEST  = 0x15,
  49         CP2112_TRANSFER_STATUS_RESPONSE = 0x16,
  50         CP2112_CANCEL_TRANSFER          = 0x17,
  51         CP2112_LOCK_BYTE                = 0x20,
  52         CP2112_USB_CONFIG               = 0x21,
  53         CP2112_MANUFACTURER_STRING      = 0x22,
  54         CP2112_PRODUCT_STRING           = 0x23,
  55         CP2112_SERIAL_STRING            = 0x24,
  56 };
  57
  58 enum {
  59         STATUS0_IDLE            = 0x00,
  60         STATUS0_BUSY            = 0x01,
  61         STATUS0_COMPLETE        = 0x02,
  62         STATUS0_ERROR           = 0x03,
  63 };
  64
  65 enum {
  66         STATUS1_TIMEOUT_NACK            = 0x00,
  67         STATUS1_TIMEOUT_BUS             = 0x01,
  68         STATUS1_ARBITRATION_LOST        = 0x02,
  69         STATUS1_READ_INCOMPLETE         = 0x03,
  70         STATUS1_WRITE_INCOMPLETE        = 0x04,
  71         STATUS1_SUCCESS                 = 0x05,
  72 };
  73
  74 struct cp2112_smbus_config_report {
  75         u8 report;              /* CP2112_SMBUS_CONFIG */
  76         __be32 clock_speed;     /* Hz */
  77         u8 device_address;      /* Stored in the upper 7 bits */
  78         u8 auto_send_read;      /* 1 = enabled, 0 = disabled */
  79         __be16 write_timeout;   /* ms, 0 = no timeout */
  80         __be16 read_timeout;    /* ms, 0 = no timeout */
  81         u8 scl_low_timeout;     /* 1 = enabled, 0 = disabled */
  82         __be16 retry_time;      /* # of retries, 0 = no limit */
  83 } __packed;
  84
  85 struct cp2112_usb_config_report {
  86         u8 report;      /* CP2112_USB_CONFIG */
  87         __le16 vid;     /* Vendor ID */
  88         __le16 pid;     /* Product ID */
  89         u8 max_power;   /* Power requested in 2mA units */
  90         u8 power_mode;  /* 0x00 = bus powered
  91                            0x01 = self powered & regulator off
  92                            0x02 = self powered & regulator on */
  93         u8 release_major;
  94         u8 release_minor;
  95         u8 mask;        /* What fields to program */
  96 } __packed;
  97
  98 struct cp2112_read_req_report {
  99         u8 report;      /* CP2112_DATA_READ_REQUEST */
 100         u8 slave_address;
 101         __be16 length;
 102 } __packed;
 103
 104 struct cp2112_write_read_req_report {
 105         u8 report;      /* CP2112_DATA_WRITE_READ_REQUEST */
 106         u8 slave_address;
 107         __be16 length;
 108         u8 target_address_length;
 109         u8 target_address[16];
 110 } __packed;
 111
 112 struct cp2112_write_req_report {
 113         u8 report;      /* CP2112_DATA_WRITE_REQUEST */
 114         u8 slave_address;
 115         u8 length;
 116         u8 data[61];
 117 } __packed;
 118
 119 struct cp2112_force_read_report {
 120         u8 report;      /* CP2112_DATA_READ_FORCE_SEND */
 121         __be16 length;
 122 } __packed;
 123
 124 struct cp2112_xfer_status_report {
 125         u8 report;      /* CP2112_TRANSFER_STATUS_RESPONSE */
 126         u8 status0;     /* STATUS0_* */
 127         u8 status1;     /* STATUS1_* */
 128         __be16 retries;
 129         __be16 length;
 130 } __packed;
 131
 132 struct cp2112_string_report {
 133         u8 dummy;               /* force .string to be aligned */
 134         struct_group_attr(contents, __packed,
 135                 u8 report;              /* CP2112_*_STRING */
 136                 u8 length;              /* length in bytes of everything after .report */
 137                 u8 type;                /* USB_DT_STRING */
 138                 wchar_t string[30];     /* UTF16_LITTLE_ENDIAN string */
 139         );
 140 } __packed;
 141
 142 /* Number of times to request transfer status before giving up waiting for a
 143    transfer to complete. This may need to be changed if SMBUS clock, retries,
 144    or read/write/scl_low timeout settings are changed. */
 145 static const int XFER_STATUS_RETRIES = 10;
 146
 147 /* Time in ms to wait for a CP2112_DATA_READ_RESPONSE or
 148    CP2112_TRANSFER_STATUS_RESPONSE. */
 149 static const int RESPONSE_TIMEOUT = 50;
 150
 151 static const struct hid_device_id cp2112_devices[] = {
 152         { HID_USB_DEVICE(USB_VENDOR_ID_CYGNAL, USB_DEVICE_ID_CYGNAL_CP2112) },
 153         { }
 154 };
 155 MODULE_DEVICE_TABLE(hid, cp2112_devices);
 156
 157 struct cp2112_device {
 158         struct i2c_adapter adap;
 159         struct hid_device *hdev;
 160         wait_queue_head_t wait;
 161         u8 read_data[61];
 162         u8 read_length;
 163         u8 hwversion;
 164         int xfer_status;
 165         atomic_t read_avail;
 166         atomic_t xfer_avail;
 167         struct gpio_chip gc;
 168         u8 *in_out_buffer;
 169         struct mutex lock;
 170
 171         bool gpio_poll;
 172         struct delayed_work gpio_poll_worker;
 173         unsigned long irq_mask;
 174         u8 gpio_prev_state;
 175 };
 176
 177 static int gpio_push_pull = CP2112_GPIO_ALL_GPIO_MASK;
 178 module_param(gpio_push_pull, int, 0644);
 179 MODULE_PARM_DESC(gpio_push_pull, "GPIO push-pull configuration bitmask");
 180
 181 static int cp2112_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 182 {
 183         struct cp2112_device *dev = gpiochip_get_data(chip);
 184         struct hid_device *hdev = dev->hdev;
 185         u8 *buf = dev->in_out_buffer;
 186         int ret;
 187
 188         mutex_lock(&dev->lock);
 189
 190         ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
 191                                  CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
 192                                  HID_REQ_GET_REPORT);
 193         if (ret != CP2112_GPIO_CONFIG_LENGTH) {
 194                 hid_err(hdev, "error requesting GPIO config: %d\n", ret);
 195                 if (ret >= 0)
 196                         ret = -EIO;
 197                 goto exit;
 198         }
 199
 200         buf[1] &= ~BIT(offset);
 201         buf[2] = gpio_push_pull;
 202
 203         ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
 204                                  CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
 205                                  HID_REQ_SET_REPORT);
 206         if (ret != CP2112_GPIO_CONFIG_LENGTH) {
 207                 hid_err(hdev, "error setting GPIO config: %d\n", ret);
 208                 if (ret >= 0)
 209                         ret = -EIO;
 210                 goto exit;
 211         }
 212
 213         ret = 0;
 214
 215 exit:
 216         mutex_unlock(&dev->lock);
 217         return ret;
 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 ? CP2112_GPIO_ALL_GPIO_MASK : 0;
 231         buf[2] = BIT(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                 hid_dbg(hdev, "I2C %s %#04x len %d\n",
 536                         str_read_write(msgs->flags & I2C_M_RD), msgs->addr, msgs->len);
 537                 if (msgs->flags & I2C_M_RD) {
 538                         read_length = msgs->len;
 539                         read_buf = msgs->buf;
 540                         count = cp2112_read_req(buf, msgs->addr, msgs->len);
 541                 } else {
 542                         count = cp2112_i2c_write_req(buf, msgs->addr,
 543                                                      msgs->buf, msgs->len);
 544                 }
 545                 if (count < 0)
 546                         return count;
 547         } else if (dev->hwversion > 1 &&  /* no repeated start in rev 1 */
 548                    num == 2 &&
 549                    msgs[0].addr == msgs[1].addr &&
 550                    !(msgs[0].flags & I2C_M_RD) && (msgs[1].flags & I2C_M_RD)) {
 551                 hid_dbg(hdev, "I2C write-read %#04x wlen %d rlen %d\n",
 552                         msgs[0].addr, msgs[0].len, msgs[1].len);
 553                 read_length = msgs[1].len;
 554                 read_buf = msgs[1].buf;
 555                 count = cp2112_i2c_write_read_req(buf, msgs[0].addr,
 556                                 msgs[0].buf, msgs[0].len, msgs[1].len);
 557                 if (count < 0)
 558                         return count;
 559         } else {
 560                 hid_err(hdev,
 561                         "Multi-message I2C transactions not supported\n");
 562                 return -EOPNOTSUPP;
 563         }
 564
 565         ret = hid_hw_power(hdev, PM_HINT_FULLON);
 566         if (ret < 0) {
 567                 hid_err(hdev, "power management error: %d\n", ret);
 568                 return ret;
 569         }
 570
 571         ret = cp2112_hid_output(hdev, buf, count, HID_OUTPUT_REPORT);
 572         if (ret < 0) {
 573                 hid_warn(hdev, "Error starting transaction: %d\n", ret);
 574                 goto power_normal;
 575         }
 576
 577         for (retries = 0; retries < XFER_STATUS_RETRIES; ++retries) {
 578                 ret = cp2112_xfer_status(dev);
 579                 if (-EBUSY == ret)
 580                         continue;
 581                 if (ret < 0)
 582                         goto power_normal;
 583                 break;
 584         }
 585
 586         if (XFER_STATUS_RETRIES <= retries) {
 587                 hid_warn(hdev, "Transfer timed out, cancelling.\n");
 588                 buf[0] = CP2112_CANCEL_TRANSFER;
 589                 buf[1] = 0x01;
 590
 591                 ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
 592                 if (ret < 0)
 593                         hid_warn(hdev, "Error cancelling transaction: %d\n",
 594                                  ret);
 595
 596                 ret = -ETIMEDOUT;
 597                 goto power_normal;
 598         }
 599
 600         for (count = 0; count < read_length;) {
 601                 ret = cp2112_read(dev, read_buf + count, read_length - count);
 602                 if (ret < 0)
 603                         goto power_normal;
 604                 if (ret == 0) {
 605                         hid_err(hdev, "read returned 0\n");
 606                         ret = -EIO;
 607                         goto power_normal;
 608                 }
 609                 count += ret;
 610                 if (count > read_length) {
 611                         /*
 612                          * The hardware returned too much data.
 613                          * This is mostly harmless because cp2112_read()
 614                          * has a limit check so didn't overrun our
 615                          * buffer.  Nevertheless, we return an error
 616                          * because something is seriously wrong and
 617                          * it shouldn't go unnoticed.
 618                          */
 619                         hid_err(hdev, "long read: %d > %zd\n",
 620                                 ret, read_length - count + ret);
 621                         ret = -EIO;
 622                         goto power_normal;
 623                 }
 624         }
 625
 626         /* return the number of transferred messages */
 627         ret = num;
 628
 629 power_normal:
 630         hid_hw_power(hdev, PM_HINT_NORMAL);
 631         hid_dbg(hdev, "I2C transfer finished: %d\n", ret);
 632         return ret;
 633 }
 634
 635 static int cp2112_xfer(struct i2c_adapter *adap, u16 addr,
 636                        unsigned short flags, char read_write, u8 command,
 637                        int size, union i2c_smbus_data *data)
 638 {
 639         struct cp2112_device *dev = (struct cp2112_device *)adap->algo_data;
 640         struct hid_device *hdev = dev->hdev;
 641         u8 buf[64];
 642         __le16 word;
 643         ssize_t count;
 644         size_t read_length = 0;
 645         unsigned int retries;
 646         int ret;
 647
 648         hid_dbg(hdev, "%s addr 0x%x flags 0x%x cmd 0x%x size %d\n",
 649                 str_write_read(read_write == I2C_SMBUS_WRITE),
 650                 addr, flags, command, size);
 651
 652         switch (size) {
 653         case I2C_SMBUS_BYTE:
 654                 read_length = 1;
 655
 656                 if (I2C_SMBUS_READ == read_write)
 657                         count = cp2112_read_req(buf, addr, read_length);
 658                 else
 659                         count = cp2112_write_req(buf, addr, command, NULL,
 660                                                  0);
 661                 break;
 662         case I2C_SMBUS_BYTE_DATA:
 663                 read_length = 1;
 664
 665                 if (I2C_SMBUS_READ == read_write)
 666                         count = cp2112_write_read_req(buf, addr, read_length,
 667                                                       command, NULL, 0);
 668                 else
 669                         count = cp2112_write_req(buf, addr, command,
 670                                                  &data->byte, 1);
 671                 break;
 672         case I2C_SMBUS_WORD_DATA:
 673                 read_length = 2;
 674                 word = cpu_to_le16(data->word);
 675
 676                 if (I2C_SMBUS_READ == read_write)
 677                         count = cp2112_write_read_req(buf, addr, read_length,
 678                                                       command, NULL, 0);
 679                 else
 680                         count = cp2112_write_req(buf, addr, command,
 681                                                  (u8 *)&word, 2);
 682                 break;
 683         case I2C_SMBUS_PROC_CALL:
 684                 size = I2C_SMBUS_WORD_DATA;
 685                 read_write = I2C_SMBUS_READ;
 686                 read_length = 2;
 687                 word = cpu_to_le16(data->word);
 688
 689                 count = cp2112_write_read_req(buf, addr, read_length, command,
 690                                               (u8 *)&word, 2);
 691                 break;
 692         case I2C_SMBUS_I2C_BLOCK_DATA:
 693                 if (read_write == I2C_SMBUS_READ) {
 694                         read_length = data->block[0];
 695                         count = cp2112_write_read_req(buf, addr, read_length,
 696                                                       command, NULL, 0);
 697                 } else {
 698                         count = cp2112_write_req(buf, addr, command,
 699                                                  data->block + 1,
 700                                                  data->block[0]);
 701                 }
 702                 break;
 703         case I2C_SMBUS_BLOCK_DATA:
 704                 if (I2C_SMBUS_READ == read_write) {
 705                         count = cp2112_write_read_req(buf, addr,
 706                                                       I2C_SMBUS_BLOCK_MAX,
 707                                                       command, NULL, 0);
 708                 } else {
 709                         count = cp2112_write_req(buf, addr, command,
 710                                                  data->block,
 711                                                  data->block[0] + 1);
 712                 }
 713                 break;
 714         case I2C_SMBUS_BLOCK_PROC_CALL:
 715                 size = I2C_SMBUS_BLOCK_DATA;
 716                 read_write = I2C_SMBUS_READ;
 717
 718                 count = cp2112_write_read_req(buf, addr, I2C_SMBUS_BLOCK_MAX,
 719                                               command, data->block,
 720                                               data->block[0] + 1);
 721                 break;
 722         default:
 723                 hid_warn(hdev, "Unsupported transaction %d\n", size);
 724                 return -EOPNOTSUPP;
 725         }
 726
 727         if (count < 0)
 728                 return count;
 729
 730         ret = hid_hw_power(hdev, PM_HINT_FULLON);
 731         if (ret < 0) {
 732                 hid_err(hdev, "power management error: %d\n", ret);
 733                 return ret;
 734         }
 735
 736         ret = cp2112_hid_output(hdev, buf, count, HID_OUTPUT_REPORT);
 737         if (ret < 0) {
 738                 hid_warn(hdev, "Error starting transaction: %d\n", ret);
 739                 goto power_normal;
 740         }
 741
 742         for (retries = 0; retries < XFER_STATUS_RETRIES; ++retries) {
 743                 ret = cp2112_xfer_status(dev);
 744                 if (-EBUSY == ret)
 745                         continue;
 746                 if (ret < 0)
 747                         goto power_normal;
 748                 break;
 749         }
 750
 751         if (XFER_STATUS_RETRIES <= retries) {
 752                 hid_warn(hdev, "Transfer timed out, cancelling.\n");
 753                 buf[0] = CP2112_CANCEL_TRANSFER;
 754                 buf[1] = 0x01;
 755
 756                 ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
 757                 if (ret < 0)
 758                         hid_warn(hdev, "Error cancelling transaction: %d\n",
 759                                  ret);
 760
 761                 ret = -ETIMEDOUT;
 762                 goto power_normal;
 763         }
 764
 765         if (I2C_SMBUS_WRITE == read_write) {
 766                 ret = 0;
 767                 goto power_normal;
 768         }
 769
 770         if (I2C_SMBUS_BLOCK_DATA == size)
 771                 read_length = ret;
 772
 773         ret = cp2112_read(dev, buf, read_length);
 774         if (ret < 0)
 775                 goto power_normal;
 776         if (ret != read_length) {
 777                 hid_warn(hdev, "short read: %d < %zd\n", ret, read_length);
 778                 ret = -EIO;
 779                 goto power_normal;
 780         }
 781
 782         switch (size) {
 783         case I2C_SMBUS_BYTE:
 784         case I2C_SMBUS_BYTE_DATA:
 785                 data->byte = buf[0];
 786                 break;
 787         case I2C_SMBUS_WORD_DATA:
 788                 data->word = le16_to_cpup((__le16 *)buf);
 789                 break;
 790         case I2C_SMBUS_I2C_BLOCK_DATA:
 791                 if (read_length > I2C_SMBUS_BLOCK_MAX) {
 792                         ret = -EINVAL;
 793                         goto power_normal;
 794                 }
 795
 796                 memcpy(data->block + 1, buf, read_length);
 797                 break;
 798         case I2C_SMBUS_BLOCK_DATA:
 799                 if (read_length > I2C_SMBUS_BLOCK_MAX) {
 800                         ret = -EPROTO;
 801                         goto power_normal;
 802                 }
 803
 804                 memcpy(data->block, buf, read_length);
 805                 break;
 806         }
 807
 808         ret = 0;
 809 power_normal:
 810         hid_hw_power(hdev, PM_HINT_NORMAL);
 811         hid_dbg(hdev, "transfer finished: %d\n", ret);
 812         return ret;
 813 }
 814
 815 static u32 cp2112_functionality(struct i2c_adapter *adap)
 816 {
 817         return I2C_FUNC_I2C |
 818                 I2C_FUNC_SMBUS_BYTE |
 819                 I2C_FUNC_SMBUS_BYTE_DATA |
 820                 I2C_FUNC_SMBUS_WORD_DATA |
 821                 I2C_FUNC_SMBUS_BLOCK_DATA |
 822                 I2C_FUNC_SMBUS_I2C_BLOCK |
 823                 I2C_FUNC_SMBUS_PROC_CALL |
 824                 I2C_FUNC_SMBUS_BLOCK_PROC_CALL;
 825 }
 826
 827 static const struct i2c_algorithm smbus_algorithm = {
 828         .master_xfer    = cp2112_i2c_xfer,
 829         .smbus_xfer     = cp2112_xfer,
 830         .functionality  = cp2112_functionality,
 831 };
 832
 833 static int cp2112_get_usb_config(struct hid_device *hdev,
 834                                  struct cp2112_usb_config_report *cfg)
 835 {
 836         int ret;
 837
 838         ret = cp2112_hid_get(hdev, CP2112_USB_CONFIG, (u8 *)cfg, sizeof(*cfg),
 839                              HID_FEATURE_REPORT);
 840         if (ret != sizeof(*cfg)) {
 841                 hid_err(hdev, "error reading usb config: %d\n", ret);
 842                 if (ret < 0)
 843                         return ret;
 844                 return -EIO;
 845         }
 846
 847         return 0;
 848 }
 849
 850 static int cp2112_set_usb_config(struct hid_device *hdev,
 851                                  struct cp2112_usb_config_report *cfg)
 852 {
 853         int ret;
 854
 855         BUG_ON(cfg->report != CP2112_USB_CONFIG);
 856
 857         ret = cp2112_hid_output(hdev, (u8 *)cfg, sizeof(*cfg),
 858                                 HID_FEATURE_REPORT);
 859         if (ret != sizeof(*cfg)) {
 860                 hid_err(hdev, "error writing usb config: %d\n", ret);
 861                 if (ret < 0)
 862                         return ret;
 863                 return -EIO;
 864         }
 865
 866         return 0;
 867 }
 868
 869 static void chmod_sysfs_attrs(struct hid_device *hdev);
 870
 871 #define CP2112_CONFIG_ATTR(name, store, format, ...) \
 872 static ssize_t name##_store(struct device *kdev, \
 873                             struct device_attribute *attr, const char *buf, \
 874                             size_t count) \
 875 { \
 876         struct hid_device *hdev = to_hid_device(kdev); \
 877         struct cp2112_usb_config_report cfg; \
 878         int ret = cp2112_get_usb_config(hdev, &cfg); \
 879         if (ret) \
 880                 return ret; \
 881         store; \
 882         ret = cp2112_set_usb_config(hdev, &cfg); \
 883         if (ret) \
 884                 return ret; \
 885         chmod_sysfs_attrs(hdev); \
 886         return count; \
 887 } \
 888 static ssize_t name##_show(struct device *kdev, \
 889                            struct device_attribute *attr, char *buf) \
 890 { \
 891         struct hid_device *hdev = to_hid_device(kdev); \
 892         struct cp2112_usb_config_report cfg; \
 893         int ret = cp2112_get_usb_config(hdev, &cfg); \
 894         if (ret) \
 895                 return ret; \
 896         return sysfs_emit(buf, format, ##__VA_ARGS__); \
 897 } \
 898 static DEVICE_ATTR_RW(name);
 899
 900 CP2112_CONFIG_ATTR(vendor_id, ({
 901         u16 vid;
 902
 903         if (sscanf(buf, "%hi", &vid) != 1)
 904                 return -EINVAL;
 905
 906         cfg.vid = cpu_to_le16(vid);
 907         cfg.mask = 0x01;
 908 }), "0x%04x\n", le16_to_cpu(cfg.vid));
 909
 910 CP2112_CONFIG_ATTR(product_id, ({
 911         u16 pid;
 912
 913         if (sscanf(buf, "%hi", &pid) != 1)
 914                 return -EINVAL;
 915
 916         cfg.pid = cpu_to_le16(pid);
 917         cfg.mask = 0x02;
 918 }), "0x%04x\n", le16_to_cpu(cfg.pid));
 919
 920 CP2112_CONFIG_ATTR(max_power, ({
 921         int mA;
 922
 923         if (sscanf(buf, "%i", &mA) != 1)
 924                 return -EINVAL;
 925
 926         cfg.max_power = (mA + 1) / 2;
 927         cfg.mask = 0x04;
 928 }), "%u mA\n", cfg.max_power * 2);
 929
 930 CP2112_CONFIG_ATTR(power_mode, ({
 931         if (sscanf(buf, "%hhi", &cfg.power_mode) != 1)
 932                 return -EINVAL;
 933
 934         cfg.mask = 0x08;
 935 }), "%u\n", cfg.power_mode);
 936
 937 CP2112_CONFIG_ATTR(release_version, ({
 938         if (sscanf(buf, "%hhi.%hhi", &cfg.release_major, &cfg.release_minor)
 939             != 2)
 940                 return -EINVAL;
 941
 942         cfg.mask = 0x10;
 943 }), "%u.%u\n", cfg.release_major, cfg.release_minor);
 944
 945 #undef CP2112_CONFIG_ATTR
 946
 947 static ssize_t pstr_store(struct device *kdev, struct device_attribute *kattr,
 948                           const char *buf, size_t count, int number)
 949 {
 950         struct hid_device *hdev = to_hid_device(kdev);
 951         struct cp2112_string_report report;
 952         int ret;
 953
 954         memset(&report, 0, sizeof(report));
 955
 956         ret = utf8s_to_utf16s(buf, count, UTF16_LITTLE_ENDIAN,
 957                               report.string, ARRAY_SIZE(report.string));
 958         report.report = number;
 959         report.length = ret * sizeof(report.string[0]) + 2;
 960         report.type = USB_DT_STRING;
 961
 962         ret = cp2112_hid_output(hdev, &report.report, report.length + 1,
 963                                 HID_FEATURE_REPORT);
 964         if (ret != report.length + 1) {
 965                 hid_err(hdev, "error writing %s string: %d\n", kattr->attr.name,
 966                         ret);
 967                 if (ret < 0)
 968                         return ret;
 969                 return -EIO;
 970         }
 971
 972         chmod_sysfs_attrs(hdev);
 973         return count;
 974 }
 975
 976 static ssize_t pstr_show(struct device *kdev, struct device_attribute *kattr,
 977                          char *buf, int number)
 978 {
 979         struct hid_device *hdev = to_hid_device(kdev);
 980         struct cp2112_string_report report;
 981         u8 length;
 982         int ret;
 983
 984         ret = cp2112_hid_get(hdev, number, (u8 *)&report.contents,
 985                              sizeof(report.contents), 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 ssize_t name##_store(struct device *kdev, struct device_attribute *kattr, \
1010                             const char *buf, size_t count) \
1011 { \
1012         return pstr_store(kdev, kattr, buf, count, _report); \
1013 } \
1014 static ssize_t name##_show(struct device *kdev, struct device_attribute *kattr, char *buf) \
1015 { \
1016         return pstr_show(kdev, kattr, buf, _report); \
1017 } \
1018 static DEVICE_ATTR_RW(name);
1019
1020 CP2112_PSTR_ATTR(manufacturer,  CP2112_MANUFACTURER_STRING);
1021 CP2112_PSTR_ATTR(product,       CP2112_PRODUCT_STRING);
1022 CP2112_PSTR_ATTR(serial,        CP2112_SERIAL_STRING);
1023
1024 #undef CP2112_PSTR_ATTR
1025
1026 static const struct attribute_group cp2112_attr_group = {
1027         .attrs = (struct attribute *[]){
1028                 &dev_attr_vendor_id.attr,
1029                 &dev_attr_product_id.attr,
1030                 &dev_attr_max_power.attr,
1031                 &dev_attr_power_mode.attr,
1032                 &dev_attr_release_version.attr,
1033                 &dev_attr_manufacturer.attr,
1034                 &dev_attr_product.attr,
1035                 &dev_attr_serial.attr,
1036                 NULL
1037         }
1038 };
1039
1040 /* Chmoding our sysfs attributes is simply a way to expose which fields in the
1041  * PROM have already been programmed. We do not depend on this preventing
1042  * writing to these attributes since the CP2112 will simply ignore writes to
1043  * already-programmed fields. This is why there is no sense in fixing this
1044  * racy behaviour.
1045  */
1046 static void chmod_sysfs_attrs(struct hid_device *hdev)
1047 {
1048         struct attribute **attr;
1049         u8 buf[2];
1050         int ret;
1051
1052         ret = cp2112_hid_get(hdev, CP2112_LOCK_BYTE, buf, sizeof(buf),
1053                              HID_FEATURE_REPORT);
1054         if (ret != sizeof(buf)) {
1055                 hid_err(hdev, "error reading lock byte: %d\n", ret);
1056                 return;
1057         }
1058
1059         for (attr = cp2112_attr_group.attrs; *attr; ++attr) {
1060                 umode_t mode = (buf[1] & 1) ? 0644 : 0444;
1061                 ret = sysfs_chmod_file(&hdev->dev.kobj, *attr, mode);
1062                 if (ret < 0)
1063                         hid_err(hdev, "error chmoding sysfs file %s\n",
1064                                 (*attr)->name);
1065                 buf[1] >>= 1;
1066         }
1067 }
1068
1069 static void cp2112_gpio_irq_ack(struct irq_data *d)
1070 {
1071 }
1072
1073 static void cp2112_gpio_irq_mask(struct irq_data *d)
1074 {
1075         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1076         struct cp2112_device *dev = gpiochip_get_data(gc);
1077         irq_hw_number_t hwirq = irqd_to_hwirq(d);
1078
1079         __clear_bit(hwirq, &dev->irq_mask);
1080         gpiochip_disable_irq(gc, hwirq);
1081 }
1082
1083 static void cp2112_gpio_irq_unmask(struct irq_data *d)
1084 {
1085         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1086         struct cp2112_device *dev = gpiochip_get_data(gc);
1087         irq_hw_number_t hwirq = irqd_to_hwirq(d);
1088
1089         gpiochip_enable_irq(gc, hwirq);
1090         __set_bit(hwirq, &dev->irq_mask);
1091 }
1092
1093 static void cp2112_gpio_poll_callback(struct work_struct *work)
1094 {
1095         struct cp2112_device *dev = container_of(work, struct cp2112_device,
1096                                                  gpio_poll_worker.work);
1097         struct irq_data *d;
1098         u8 gpio_mask;
1099         u32 irq_type;
1100         int irq, virq, ret;
1101
1102         ret = cp2112_gpio_get_all(&dev->gc);
1103         if (ret == -ENODEV) /* the hardware has been disconnected */
1104                 return;
1105         if (ret < 0)
1106                 goto exit;
1107
1108         gpio_mask = ret;
1109         for_each_set_bit(virq, &dev->irq_mask, CP2112_GPIO_MAX_GPIO) {
1110                 irq = irq_find_mapping(dev->gc.irq.domain, virq);
1111                 if (!irq)
1112                         continue;
1113
1114                 d = irq_get_irq_data(irq);
1115                 if (!d)
1116                         continue;
1117
1118                 irq_type = irqd_get_trigger_type(d);
1119
1120                 if (gpio_mask & BIT(virq)) {
1121                         /* Level High */
1122
1123                         if (irq_type & IRQ_TYPE_LEVEL_HIGH)
1124                                 handle_nested_irq(irq);
1125
1126                         if ((irq_type & IRQ_TYPE_EDGE_RISING) &&
1127                             !(dev->gpio_prev_state & BIT(virq)))
1128                                 handle_nested_irq(irq);
1129                 } else {
1130                         /* Level Low */
1131
1132                         if (irq_type & IRQ_TYPE_LEVEL_LOW)
1133                                 handle_nested_irq(irq);
1134
1135                         if ((irq_type & IRQ_TYPE_EDGE_FALLING) &&
1136                             (dev->gpio_prev_state & BIT(virq)))
1137                                 handle_nested_irq(irq);
1138                 }
1139         }
1140
1141         dev->gpio_prev_state = gpio_mask;
1142
1143 exit:
1144         if (dev->gpio_poll)
1145                 schedule_delayed_work(&dev->gpio_poll_worker, 10);
1146 }
1147
1148
1149 static unsigned int cp2112_gpio_irq_startup(struct irq_data *d)
1150 {
1151         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1152         struct cp2112_device *dev = gpiochip_get_data(gc);
1153
1154         INIT_DELAYED_WORK(&dev->gpio_poll_worker, cp2112_gpio_poll_callback);
1155
1156         if (!dev->gpio_poll) {
1157                 dev->gpio_poll = true;
1158                 schedule_delayed_work(&dev->gpio_poll_worker, 0);
1159         }
1160
1161         cp2112_gpio_irq_unmask(d);
1162         return 0;
1163 }
1164
1165 static void cp2112_gpio_irq_shutdown(struct irq_data *d)
1166 {
1167         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1168         struct cp2112_device *dev = gpiochip_get_data(gc);
1169
1170         cp2112_gpio_irq_mask(d);
1171         cancel_delayed_work_sync(&dev->gpio_poll_worker);
1172 }
1173
1174 static int cp2112_gpio_irq_type(struct irq_data *d, unsigned int type)
1175 {
1176         return 0;
1177 }
1178
1179 static const struct irq_chip cp2112_gpio_irqchip = {
1180         .name = "cp2112-gpio",
1181         .irq_startup = cp2112_gpio_irq_startup,
1182         .irq_shutdown = cp2112_gpio_irq_shutdown,
1183         .irq_ack = cp2112_gpio_irq_ack,
1184         .irq_mask = cp2112_gpio_irq_mask,
1185         .irq_unmask = cp2112_gpio_irq_unmask,
1186         .irq_set_type = cp2112_gpio_irq_type,
1187         .flags = IRQCHIP_MASK_ON_SUSPEND | IRQCHIP_IMMUTABLE,
1188         GPIOCHIP_IRQ_RESOURCE_HELPERS,
1189 };
1190
1191 static int cp2112_probe(struct hid_device *hdev, const struct hid_device_id *id)
1192 {
1193         struct cp2112_device *dev;
1194         u8 buf[3];
1195         struct cp2112_smbus_config_report config;
1196         struct gpio_irq_chip *girq;
1197         int ret;
1198
1199         dev = devm_kzalloc(&hdev->dev, sizeof(*dev), GFP_KERNEL);
1200         if (!dev)
1201                 return -ENOMEM;
1202
1203         dev->in_out_buffer = devm_kzalloc(&hdev->dev, CP2112_REPORT_MAX_LENGTH,
1204                                           GFP_KERNEL);
1205         if (!dev->in_out_buffer)
1206                 return -ENOMEM;
1207
1208         mutex_init(&dev->lock);
1209
1210         ret = hid_parse(hdev);
1211         if (ret) {
1212                 hid_err(hdev, "parse failed\n");
1213                 return ret;
1214         }
1215
1216         ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
1217         if (ret) {
1218                 hid_err(hdev, "hw start failed\n");
1219                 return ret;
1220         }
1221
1222         ret = hid_hw_open(hdev);
1223         if (ret) {
1224                 hid_err(hdev, "hw open failed\n");
1225                 goto err_hid_stop;
1226         }
1227
1228         ret = hid_hw_power(hdev, PM_HINT_FULLON);
1229         if (ret < 0) {
1230                 hid_err(hdev, "power management error: %d\n", ret);
1231                 goto err_hid_close;
1232         }
1233
1234         ret = cp2112_hid_get(hdev, CP2112_GET_VERSION_INFO, buf, sizeof(buf),
1235                              HID_FEATURE_REPORT);
1236         if (ret != sizeof(buf)) {
1237                 hid_err(hdev, "error requesting version\n");
1238                 if (ret >= 0)
1239                         ret = -EIO;
1240                 goto err_power_normal;
1241         }
1242
1243         hid_info(hdev, "Part Number: 0x%02X Device Version: 0x%02X\n",
1244                  buf[1], buf[2]);
1245
1246         ret = cp2112_hid_get(hdev, CP2112_SMBUS_CONFIG, (u8 *)&config,
1247                              sizeof(config), HID_FEATURE_REPORT);
1248         if (ret != sizeof(config)) {
1249                 hid_err(hdev, "error requesting SMBus config\n");
1250                 if (ret >= 0)
1251                         ret = -EIO;
1252                 goto err_power_normal;
1253         }
1254
1255         config.retry_time = cpu_to_be16(1);
1256
1257         ret = cp2112_hid_output(hdev, (u8 *)&config, sizeof(config),
1258                                 HID_FEATURE_REPORT);
1259         if (ret != sizeof(config)) {
1260                 hid_err(hdev, "error setting SMBus config\n");
1261                 if (ret >= 0)
1262                         ret = -EIO;
1263                 goto err_power_normal;
1264         }
1265
1266         hid_set_drvdata(hdev, (void *)dev);
1267         dev->hdev               = hdev;
1268         dev->adap.owner         = THIS_MODULE;
1269         dev->adap.class         = I2C_CLASS_HWMON;
1270         dev->adap.algo          = &smbus_algorithm;
1271         dev->adap.algo_data     = dev;
1272         dev->adap.dev.parent    = &hdev->dev;
1273         snprintf(dev->adap.name, sizeof(dev->adap.name),
1274                  "CP2112 SMBus Bridge on hidraw%d",
1275                  ((struct hidraw *)hdev->hidraw)->minor);
1276         dev->hwversion = buf[2];
1277         init_waitqueue_head(&dev->wait);
1278
1279         hid_device_io_start(hdev);
1280         ret = i2c_add_adapter(&dev->adap);
1281         hid_device_io_stop(hdev);
1282
1283         if (ret) {
1284                 hid_err(hdev, "error registering i2c adapter\n");
1285                 goto err_power_normal;
1286         }
1287
1288         hid_dbg(hdev, "adapter registered\n");
1289
1290         dev->gc.label                   = "cp2112_gpio";
1291         dev->gc.direction_input         = cp2112_gpio_direction_input;
1292         dev->gc.direction_output        = cp2112_gpio_direction_output;
1293         dev->gc.set                     = cp2112_gpio_set;
1294         dev->gc.get                     = cp2112_gpio_get;
1295         dev->gc.base                    = -1;
1296         dev->gc.ngpio                   = CP2112_GPIO_MAX_GPIO;
1297         dev->gc.can_sleep               = 1;
1298         dev->gc.parent                  = &hdev->dev;
1299
1300         girq = &dev->gc.irq;
1301         gpio_irq_chip_set_chip(girq, &cp2112_gpio_irqchip);
1302         /* The event comes from the outside so no parent handler */
1303         girq->parent_handler = NULL;
1304         girq->num_parents = 0;
1305         girq->parents = NULL;
1306         girq->default_type = IRQ_TYPE_NONE;
1307         girq->handler = handle_simple_irq;
1308         girq->threaded = true;
1309
1310         ret = gpiochip_add_data(&dev->gc, dev);
1311         if (ret < 0) {
1312                 hid_err(hdev, "error registering gpio chip\n");
1313                 goto err_free_i2c;
1314         }
1315
1316         ret = sysfs_create_group(&hdev->dev.kobj, &cp2112_attr_group);
1317         if (ret < 0) {
1318                 hid_err(hdev, "error creating sysfs attrs\n");
1319                 goto err_gpiochip_remove;
1320         }
1321
1322         chmod_sysfs_attrs(hdev);
1323         hid_hw_power(hdev, PM_HINT_NORMAL);
1324
1325         return ret;
1326
1327 err_gpiochip_remove:
1328         gpiochip_remove(&dev->gc);
1329 err_free_i2c:
1330         i2c_del_adapter(&dev->adap);
1331 err_power_normal:
1332         hid_hw_power(hdev, PM_HINT_NORMAL);
1333 err_hid_close:
1334         hid_hw_close(hdev);
1335 err_hid_stop:
1336         hid_hw_stop(hdev);
1337         return ret;
1338 }
1339
1340 static void cp2112_remove(struct hid_device *hdev)
1341 {
1342         struct cp2112_device *dev = hid_get_drvdata(hdev);
1343
1344         sysfs_remove_group(&hdev->dev.kobj, &cp2112_attr_group);
1345         i2c_del_adapter(&dev->adap);
1346
1347         if (dev->gpio_poll) {
1348                 dev->gpio_poll = false;
1349                 cancel_delayed_work_sync(&dev->gpio_poll_worker);
1350         }
1351
1352         gpiochip_remove(&dev->gc);
1353         /* i2c_del_adapter has finished removing all i2c devices from our
1354          * adapter. Well behaved devices should no longer call our cp2112_xfer
1355          * and should have waited for any pending calls to finish. It has also
1356          * waited for device_unregister(&adap->dev) to complete. Therefore we
1357          * can safely free our struct cp2112_device.
1358          */
1359         hid_hw_close(hdev);
1360         hid_hw_stop(hdev);
1361 }
1362
1363 static int cp2112_raw_event(struct hid_device *hdev, struct hid_report *report,
1364                             u8 *data, int size)
1365 {
1366         struct cp2112_device *dev = hid_get_drvdata(hdev);
1367         struct cp2112_xfer_status_report *xfer = (void *)data;
1368
1369         switch (data[0]) {
1370         case CP2112_TRANSFER_STATUS_RESPONSE:
1371                 hid_dbg(hdev, "xfer status: %02x %02x %04x %04x\n",
1372                         xfer->status0, xfer->status1,
1373                         be16_to_cpu(xfer->retries), be16_to_cpu(xfer->length));
1374
1375                 switch (xfer->status0) {
1376                 case STATUS0_IDLE:
1377                         dev->xfer_status = -EAGAIN;
1378                         break;
1379                 case STATUS0_BUSY:
1380                         dev->xfer_status = -EBUSY;
1381                         break;
1382                 case STATUS0_COMPLETE:
1383                         dev->xfer_status = be16_to_cpu(xfer->length);
1384                         break;
1385                 case STATUS0_ERROR:
1386                         switch (xfer->status1) {
1387                         case STATUS1_TIMEOUT_NACK:
1388                         case STATUS1_TIMEOUT_BUS:
1389                                 dev->xfer_status = -ETIMEDOUT;
1390                                 break;
1391                         default:
1392                                 dev->xfer_status = -EIO;
1393                                 break;
1394                         }
1395                         break;
1396                 default:
1397                         dev->xfer_status = -EINVAL;
1398                         break;
1399                 }
1400
1401                 atomic_set(&dev->xfer_avail, 1);
1402                 break;
1403         case CP2112_DATA_READ_RESPONSE:
1404                 hid_dbg(hdev, "read response: %02x %02x\n", data[1], data[2]);
1405
1406                 dev->read_length = data[2];
1407                 if (dev->read_length > sizeof(dev->read_data))
1408                         dev->read_length = sizeof(dev->read_data);
1409
1410                 memcpy(dev->read_data, &data[3], dev->read_length);
1411                 atomic_set(&dev->read_avail, 1);
1412                 break;
1413         default:
1414                 hid_err(hdev, "unknown report\n");
1415
1416                 return 0;
1417         }
1418
1419         wake_up_interruptible(&dev->wait);
1420         return 1;
1421 }
1422
1423 static struct hid_driver cp2112_driver = {
1424         .name           = "cp2112",
1425         .id_table       = cp2112_devices,
1426         .probe          = cp2112_probe,
1427         .remove         = cp2112_remove,
1428         .raw_event      = cp2112_raw_event,
1429 };
1430
1431 module_hid_driver(cp2112_driver);
1432 MODULE_DESCRIPTION("Silicon Labs HID USB to SMBus master bridge");
1433 MODULE_AUTHOR("David Barksdale <dbarksdale@uplogix.com>");
1434 MODULE_LICENSE("GPL");
1435