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