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/gpio/consumer.h>
  20 #include <linux/gpio/machine.h>
  21 #include <linux/gpio/driver.h>
  22 #include <linux/hid.h>
  23 #include <linux/hidraw.h>
  24 #include <linux/i2c.h>
  25 #include <linux/module.h>
  26 #include <linux/nls.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
  35 enum {
  36         CP2112_GPIO_CONFIG              = 0x02,
  37         CP2112_GPIO_GET                 = 0x03,
  38         CP2112_GPIO_SET                 = 0x04,
  39         CP2112_GET_VERSION_INFO         = 0x05,
  40         CP2112_SMBUS_CONFIG             = 0x06,
  41         CP2112_DATA_READ_REQUEST        = 0x10,
  42         CP2112_DATA_WRITE_READ_REQUEST  = 0x11,
  43         CP2112_DATA_READ_FORCE_SEND     = 0x12,
  44         CP2112_DATA_READ_RESPONSE       = 0x13,
  45         CP2112_DATA_WRITE_REQUEST       = 0x14,
  46         CP2112_TRANSFER_STATUS_REQUEST  = 0x15,
  47         CP2112_TRANSFER_STATUS_RESPONSE = 0x16,
  48         CP2112_CANCEL_TRANSFER          = 0x17,
  49         CP2112_LOCK_BYTE                = 0x20,
  50         CP2112_USB_CONFIG               = 0x21,
  51         CP2112_MANUFACTURER_STRING      = 0x22,
  52         CP2112_PRODUCT_STRING           = 0x23,
  53         CP2112_SERIAL_STRING            = 0x24,
  54 };
  55
  56 enum {
  57         STATUS0_IDLE            = 0x00,
  58         STATUS0_BUSY            = 0x01,
  59         STATUS0_COMPLETE        = 0x02,
  60         STATUS0_ERROR           = 0x03,
  61 };
  62
  63 enum {
  64         STATUS1_TIMEOUT_NACK            = 0x00,
  65         STATUS1_TIMEOUT_BUS             = 0x01,
  66         STATUS1_ARBITRATION_LOST        = 0x02,
  67         STATUS1_READ_INCOMPLETE         = 0x03,
  68         STATUS1_WRITE_INCOMPLETE        = 0x04,
  69         STATUS1_SUCCESS                 = 0x05,
  70 };
  71
  72 struct cp2112_smbus_config_report {
  73         u8 report;              /* CP2112_SMBUS_CONFIG */
  74         __be32 clock_speed;     /* Hz */
  75         u8 device_address;      /* Stored in the upper 7 bits */
  76         u8 auto_send_read;      /* 1 = enabled, 0 = disabled */
  77         __be16 write_timeout;   /* ms, 0 = no timeout */
  78         __be16 read_timeout;    /* ms, 0 = no timeout */
  79         u8 scl_low_timeout;     /* 1 = enabled, 0 = disabled */
  80         __be16 retry_time;      /* # of retries, 0 = no limit */
  81 } __packed;
  82
  83 struct cp2112_usb_config_report {
  84         u8 report;      /* CP2112_USB_CONFIG */
  85         __le16 vid;     /* Vendor ID */
  86         __le16 pid;     /* Product ID */
  87         u8 max_power;   /* Power requested in 2mA units */
  88         u8 power_mode;  /* 0x00 = bus powered
  89                            0x01 = self powered & regulator off
  90                            0x02 = self powered & regulator on */
  91         u8 release_major;
  92         u8 release_minor;
  93         u8 mask;        /* What fields to program */
  94 } __packed;
  95
  96 struct cp2112_read_req_report {
  97         u8 report;      /* CP2112_DATA_READ_REQUEST */
  98         u8 slave_address;
  99         __be16 length;
 100 } __packed;
 101
 102 struct cp2112_write_read_req_report {
 103         u8 report;      /* CP2112_DATA_WRITE_READ_REQUEST */
 104         u8 slave_address;
 105         __be16 length;
 106         u8 target_address_length;
 107         u8 target_address[16];
 108 } __packed;
 109
 110 struct cp2112_write_req_report {
 111         u8 report;      /* CP2112_DATA_WRITE_REQUEST */
 112         u8 slave_address;
 113         u8 length;
 114         u8 data[61];
 115 } __packed;
 116
 117 struct cp2112_force_read_report {
 118         u8 report;      /* CP2112_DATA_READ_FORCE_SEND */
 119         __be16 length;
 120 } __packed;
 121
 122 struct cp2112_xfer_status_report {
 123         u8 report;      /* CP2112_TRANSFER_STATUS_RESPONSE */
 124         u8 status0;     /* STATUS0_* */
 125         u8 status1;     /* STATUS1_* */
 126         __be16 retries;
 127         __be16 length;
 128 } __packed;
 129
 130 struct cp2112_string_report {
 131         u8 dummy;               /* force .string to be aligned */
 132         u8 report;              /* CP2112_*_STRING */
 133         u8 length;              /* length in bytes of everyting after .report */
 134         u8 type;                /* USB_DT_STRING */
 135         wchar_t string[30];     /* UTF16_LITTLE_ENDIAN string */
 136 } __packed;
 137
 138 /* Number of times to request transfer status before giving up waiting for a
 139    transfer to complete. This may need to be changed if SMBUS clock, retries,
 140    or read/write/scl_low timeout settings are changed. */
 141 static const int XFER_STATUS_RETRIES = 10;
 142
 143 /* Time in ms to wait for a CP2112_DATA_READ_RESPONSE or
 144    CP2112_TRANSFER_STATUS_RESPONSE. */
 145 static const int RESPONSE_TIMEOUT = 50;
 146
 147 static const struct hid_device_id cp2112_devices[] = {
 148         { HID_USB_DEVICE(USB_VENDOR_ID_CYGNAL, USB_DEVICE_ID_CYGNAL_CP2112) },
 149         { }
 150 };
 151 MODULE_DEVICE_TABLE(hid, cp2112_devices);
 152
 153 struct cp2112_device {
 154         struct i2c_adapter adap;
 155         struct hid_device *hdev;
 156         wait_queue_head_t wait;
 157         u8 read_data[61];
 158         u8 read_length;
 159         u8 hwversion;
 160         int xfer_status;
 161         atomic_t read_avail;
 162         atomic_t xfer_avail;
 163         struct gpio_chip gc;
 164         struct irq_chip irq;
 165         u8 *in_out_buffer;
 166         struct mutex lock;
 167
 168         struct gpio_desc *desc[8];
 169         bool gpio_poll;
 170         struct delayed_work gpio_poll_worker;
 171         unsigned long irq_mask;
 172         u8 gpio_prev_state;
 173 };
 174
 175 static int gpio_push_pull = 0xFF;
 176 module_param(gpio_push_pull, int, S_IRUGO | S_IWUSR);
 177 MODULE_PARM_DESC(gpio_push_pull, "GPIO push-pull configuration bitmask");
 178
 179 static int cp2112_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 180 {
 181         struct cp2112_device *dev = gpiochip_get_data(chip);
 182         struct hid_device *hdev = dev->hdev;
 183         u8 *buf = dev->in_out_buffer;
 184         int ret;
 185
 186         mutex_lock(&dev->lock);
 187
 188         ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
 189                                  CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
 190                                  HID_REQ_GET_REPORT);
 191         if (ret != CP2112_GPIO_CONFIG_LENGTH) {
 192                 hid_err(hdev, "error requesting GPIO config: %d\n", ret);
 193                 if (ret >= 0)
 194                         ret = -EIO;
 195                 goto exit;
 196         }
 197
 198         buf[1] &= ~(1 << offset);
 199         buf[2] = gpio_push_pull;
 200
 201         ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
 202                                  CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
 203                                  HID_REQ_SET_REPORT);
 204         if (ret != CP2112_GPIO_CONFIG_LENGTH) {
 205                 hid_err(hdev, "error setting GPIO config: %d\n", ret);
 206                 if (ret >= 0)
 207                         ret = -EIO;
 208                 goto exit;
 209         }
 210
 211         ret = 0;
 212
 213 exit:
 214         mutex_unlock(&dev->lock);
 215         return ret;
 216 }
 217
 218 static void cp2112_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 219 {
 220         struct cp2112_device *dev = gpiochip_get_data(chip);
 221         struct hid_device *hdev = dev->hdev;
 222         u8 *buf = dev->in_out_buffer;
 223         int ret;
 224
 225         mutex_lock(&dev->lock);
 226
 227         buf[0] = CP2112_GPIO_SET;
 228         buf[1] = value ? 0xff : 0;
 229         buf[2] = 1 << offset;
 230
 231         ret = hid_hw_raw_request(hdev, CP2112_GPIO_SET, buf,
 232                                  CP2112_GPIO_SET_LENGTH, HID_FEATURE_REPORT,
 233                                  HID_REQ_SET_REPORT);
 234         if (ret < 0)
 235                 hid_err(hdev, "error setting GPIO values: %d\n", ret);
 236
 237         mutex_unlock(&dev->lock);
 238 }
 239
 240 static int cp2112_gpio_get_all(struct gpio_chip *chip)
 241 {
 242         struct cp2112_device *dev = gpiochip_get_data(chip);
 243         struct hid_device *hdev = dev->hdev;
 244         u8 *buf = dev->in_out_buffer;
 245         int ret;
 246
 247         mutex_lock(&dev->lock);
 248
 249         ret = hid_hw_raw_request(hdev, CP2112_GPIO_GET, buf,
 250                                  CP2112_GPIO_GET_LENGTH, HID_FEATURE_REPORT,
 251                                  HID_REQ_GET_REPORT);
 252         if (ret != CP2112_GPIO_GET_LENGTH) {
 253                 hid_err(hdev, "error requesting GPIO values: %d\n", ret);
 254                 ret = ret < 0 ? ret : -EIO;
 255                 goto exit;
 256         }
 257
 258         ret = buf[1];
 259
 260 exit:
 261         mutex_unlock(&dev->lock);
 262
 263         return ret;
 264 }
 265
 266 static int cp2112_gpio_get(struct gpio_chip *chip, unsigned int offset)
 267 {
 268         int ret;
 269
 270         ret = cp2112_gpio_get_all(chip);
 271         if (ret < 0)
 272                 return ret;
 273
 274         return (ret >> offset) & 1;
 275 }
 276
 277 static int cp2112_gpio_direction_output(struct gpio_chip *chip,
 278                                         unsigned offset, int value)
 279 {
 280         struct cp2112_device *dev = gpiochip_get_data(chip);
 281         struct hid_device *hdev = dev->hdev;
 282         u8 *buf = dev->in_out_buffer;
 283         int ret;
 284
 285         mutex_lock(&dev->lock);
 286
 287         ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
 288                                  CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
 289                                  HID_REQ_GET_REPORT);
 290         if (ret != CP2112_GPIO_CONFIG_LENGTH) {
 291                 hid_err(hdev, "error requesting GPIO config: %d\n", ret);
 292                 goto fail;
 293         }
 294
 295         buf[1] |= 1 << offset;
 296         buf[2] = gpio_push_pull;
 297
 298         ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
 299                                  CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
 300                                  HID_REQ_SET_REPORT);
 301         if (ret < 0) {
 302                 hid_err(hdev, "error setting GPIO config: %d\n", ret);
 303                 goto fail;
 304         }
 305
 306         mutex_unlock(&dev->lock);
 307
 308         /*
 309          * Set gpio value when output direction is already set,
 310          * as specified in AN495, Rev. 0.2, cpt. 4.4
 311          */
 312         cp2112_gpio_set(chip, offset, value);
 313
 314         return 0;
 315
 316 fail:
 317         mutex_unlock(&dev->lock);
 318         return ret < 0 ? ret : -EIO;
 319 }
 320
 321 static int cp2112_hid_get(struct hid_device *hdev, unsigned char report_number,
 322                           u8 *data, size_t count, unsigned char report_type)
 323 {
 324         u8 *buf;
 325         int ret;
 326
 327         buf = kmalloc(count, GFP_KERNEL);
 328         if (!buf)
 329                 return -ENOMEM;
 330
 331         ret = hid_hw_raw_request(hdev, report_number, buf, count,
 332                                        report_type, HID_REQ_GET_REPORT);
 333         memcpy(data, buf, count);
 334         kfree(buf);
 335         return ret;
 336 }
 337
 338 static int cp2112_hid_output(struct hid_device *hdev, u8 *data, size_t count,
 339                              unsigned char report_type)
 340 {
 341         u8 *buf;
 342         int ret;
 343
 344         buf = kmemdup(data, count, GFP_KERNEL);
 345         if (!buf)
 346                 return -ENOMEM;
 347
 348         if (report_type == HID_OUTPUT_REPORT)
 349                 ret = hid_hw_output_report(hdev, buf, count);
 350         else
 351                 ret = hid_hw_raw_request(hdev, buf[0], buf, count, report_type,
 352                                 HID_REQ_SET_REPORT);
 353
 354         kfree(buf);
 355         return ret;
 356 }
 357
 358 static int cp2112_wait(struct cp2112_device *dev, atomic_t *avail)
 359 {
 360         int ret = 0;
 361
 362         /* We have sent either a CP2112_TRANSFER_STATUS_REQUEST or a
 363          * CP2112_DATA_READ_FORCE_SEND and we are waiting for the response to
 364          * come in cp2112_raw_event or timeout. There will only be one of these
 365          * in flight at any one time. The timeout is extremely large and is a
 366          * last resort if the CP2112 has died. If we do timeout we don't expect
 367          * to receive the response which would cause data races, it's not like
 368          * we can do anything about it anyway.
 369          */
 370         ret = wait_event_interruptible_timeout(dev->wait,
 371                 atomic_read(avail), msecs_to_jiffies(RESPONSE_TIMEOUT));
 372         if (-ERESTARTSYS == ret)
 373                 return ret;
 374         if (!ret)
 375                 return -ETIMEDOUT;
 376
 377         atomic_set(avail, 0);
 378         return 0;
 379 }
 380
 381 static int cp2112_xfer_status(struct cp2112_device *dev)
 382 {
 383         struct hid_device *hdev = dev->hdev;
 384         u8 buf[2];
 385         int ret;
 386
 387         buf[0] = CP2112_TRANSFER_STATUS_REQUEST;
 388         buf[1] = 0x01;
 389         atomic_set(&dev->xfer_avail, 0);
 390
 391         ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
 392         if (ret < 0) {
 393                 hid_warn(hdev, "Error requesting status: %d\n", ret);
 394                 return ret;
 395         }
 396
 397         ret = cp2112_wait(dev, &dev->xfer_avail);
 398         if (ret)
 399                 return ret;
 400
 401         return dev->xfer_status;
 402 }
 403
 404 static int cp2112_read(struct cp2112_device *dev, u8 *data, size_t size)
 405 {
 406         struct hid_device *hdev = dev->hdev;
 407         struct cp2112_force_read_report report;
 408         int ret;
 409
 410         if (size > sizeof(dev->read_data))
 411                 size = sizeof(dev->read_data);
 412         report.report = CP2112_DATA_READ_FORCE_SEND;
 413         report.length = cpu_to_be16(size);
 414
 415         atomic_set(&dev->read_avail, 0);
 416
 417         ret = cp2112_hid_output(hdev, &report.report, sizeof(report),
 418                                 HID_OUTPUT_REPORT);
 419         if (ret < 0) {
 420                 hid_warn(hdev, "Error requesting data: %d\n", ret);
 421                 return ret;
 422         }
 423
 424         ret = cp2112_wait(dev, &dev->read_avail);
 425         if (ret)
 426                 return ret;
 427
 428         hid_dbg(hdev, "read %d of %zd bytes requested\n",
 429                 dev->read_length, size);
 430
 431         if (size > dev->read_length)
 432                 size = dev->read_length;
 433
 434         memcpy(data, dev->read_data, size);
 435         return dev->read_length;
 436 }
 437
 438 static int cp2112_read_req(void *buf, u8 slave_address, u16 length)
 439 {
 440         struct cp2112_read_req_report *report = buf;
 441
 442         if (length < 1 || length > 512)
 443                 return -EINVAL;
 444
 445         report->report = CP2112_DATA_READ_REQUEST;
 446         report->slave_address = slave_address << 1;
 447         report->length = cpu_to_be16(length);
 448         return sizeof(*report);
 449 }
 450
 451 static int cp2112_write_read_req(void *buf, u8 slave_address, u16 length,
 452                                  u8 command, u8 *data, u8 data_length)
 453 {
 454         struct cp2112_write_read_req_report *report = buf;
 455
 456         if (length < 1 || length > 512
 457             || data_length > sizeof(report->target_address) - 1)
 458                 return -EINVAL;
 459
 460         report->report = CP2112_DATA_WRITE_READ_REQUEST;
 461         report->slave_address = slave_address << 1;
 462         report->length = cpu_to_be16(length);
 463         report->target_address_length = data_length + 1;
 464         report->target_address[0] = command;
 465         memcpy(&report->target_address[1], data, data_length);
 466         return data_length + 6;
 467 }
 468
 469 static int cp2112_write_req(void *buf, u8 slave_address, u8 command, u8 *data,
 470                             u8 data_length)
 471 {
 472         struct cp2112_write_req_report *report = buf;
 473
 474         if (data_length > sizeof(report->data) - 1)
 475                 return -EINVAL;
 476
 477         report->report = CP2112_DATA_WRITE_REQUEST;
 478         report->slave_address = slave_address << 1;
 479         report->length = data_length + 1;
 480         report->data[0] = command;
 481         memcpy(&report->data[1], data, data_length);
 482         return data_length + 4;
 483 }
 484
 485 static int cp2112_i2c_write_req(void *buf, u8 slave_address, u8 *data,
 486                                 u8 data_length)
 487 {
 488         struct cp2112_write_req_report *report = buf;
 489
 490         if (data_length > sizeof(report->data))
 491                 return -EINVAL;
 492
 493         report->report = CP2112_DATA_WRITE_REQUEST;
 494         report->slave_address = slave_address << 1;
 495         report->length = data_length;
 496         memcpy(report->data, data, data_length);
 497         return data_length + 3;
 498 }
 499
 500 static int cp2112_i2c_write_read_req(void *buf, u8 slave_address,
 501                                      u8 *addr, int addr_length,
 502                                      int read_length)
 503 {
 504         struct cp2112_write_read_req_report *report = buf;
 505
 506         if (read_length < 1 || read_length > 512 ||
 507             addr_length > sizeof(report->target_address))
 508                 return -EINVAL;
 509
 510         report->report = CP2112_DATA_WRITE_READ_REQUEST;
 511         report->slave_address = slave_address << 1;
 512         report->length = cpu_to_be16(read_length);
 513         report->target_address_length = addr_length;
 514         memcpy(report->target_address, addr, addr_length);
 515         return addr_length + 5;
 516 }
 517
 518 static int cp2112_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
 519                            int num)
 520 {
 521         struct cp2112_device *dev = (struct cp2112_device *)adap->algo_data;
 522         struct hid_device *hdev = dev->hdev;
 523         u8 buf[64];
 524         ssize_t count;
 525         ssize_t read_length = 0;
 526         u8 *read_buf = NULL;
 527         unsigned int retries;
 528         int ret;
 529
 530         hid_dbg(hdev, "I2C %d messages\n", num);
 531
 532         if (num == 1) {
 533                 if (msgs->flags & I2C_M_RD) {
 534                         hid_dbg(hdev, "I2C read %#04x len %d\n",
 535                                 msgs->addr, msgs->len);
 536                         read_length = msgs->len;
 537                         read_buf = msgs->buf;
 538                         count = cp2112_read_req(buf, msgs->addr, msgs->len);
 539                 } else {
 540                         hid_dbg(hdev, "I2C write %#04x len %d\n",
 541                                 msgs->addr, msgs->len);
 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                 read_write == I2C_SMBUS_WRITE ? "write" : "read",
 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 scnprintf(buf, PAGE_SIZE, 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 struct cp2112_pstring_attribute {
 948         struct device_attribute attr;
 949         unsigned char report;
 950 };
 951
 952 static ssize_t pstr_store(struct device *kdev,
 953                           struct device_attribute *kattr, const char *buf,
 954                           size_t count)
 955 {
 956         struct hid_device *hdev = to_hid_device(kdev);
 957         struct cp2112_pstring_attribute *attr =
 958                 container_of(kattr, struct cp2112_pstring_attribute, attr);
 959         struct cp2112_string_report report;
 960         int ret;
 961
 962         memset(&report, 0, sizeof(report));
 963
 964         ret = utf8s_to_utf16s(buf, count, UTF16_LITTLE_ENDIAN,
 965                               report.string, ARRAY_SIZE(report.string));
 966         report.report = attr->report;
 967         report.length = ret * sizeof(report.string[0]) + 2;
 968         report.type = USB_DT_STRING;
 969
 970         ret = cp2112_hid_output(hdev, &report.report, report.length + 1,
 971                                 HID_FEATURE_REPORT);
 972         if (ret != report.length + 1) {
 973                 hid_err(hdev, "error writing %s string: %d\n", kattr->attr.name,
 974                         ret);
 975                 if (ret < 0)
 976                         return ret;
 977                 return -EIO;
 978         }
 979
 980         chmod_sysfs_attrs(hdev);
 981         return count;
 982 }
 983
 984 static ssize_t pstr_show(struct device *kdev,
 985                          struct device_attribute *kattr, char *buf)
 986 {
 987         struct hid_device *hdev = to_hid_device(kdev);
 988         struct cp2112_pstring_attribute *attr =
 989                 container_of(kattr, struct cp2112_pstring_attribute, attr);
 990         struct cp2112_string_report report;
 991         u8 length;
 992         int ret;
 993
 994         ret = cp2112_hid_get(hdev, attr->report, &report.report,
 995                              sizeof(report) - 1, HID_FEATURE_REPORT);
 996         if (ret < 3) {
 997                 hid_err(hdev, "error reading %s string: %d\n", kattr->attr.name,
 998                         ret);
 999                 if (ret < 0)
1000                         return ret;
1001                 return -EIO;
1002         }
1003
1004         if (report.length < 2) {
1005                 hid_err(hdev, "invalid %s string length: %d\n",
1006                         kattr->attr.name, report.length);
1007                 return -EIO;
1008         }
1009
1010         length = report.length > ret - 1 ? ret - 1 : report.length;
1011         length = (length - 2) / sizeof(report.string[0]);
1012         ret = utf16s_to_utf8s(report.string, length, UTF16_LITTLE_ENDIAN, buf,
1013                               PAGE_SIZE - 1);
1014         buf[ret++] = '\n';
1015         return ret;
1016 }
1017
1018 #define CP2112_PSTR_ATTR(name, _report) \
1019 static struct cp2112_pstring_attribute dev_attr_##name = { \
1020         .attr = __ATTR(name, (S_IWUSR | S_IRUGO), pstr_show, pstr_store), \
1021         .report = _report, \
1022 };
1023
1024 CP2112_PSTR_ATTR(manufacturer,  CP2112_MANUFACTURER_STRING);
1025 CP2112_PSTR_ATTR(product,       CP2112_PRODUCT_STRING);
1026 CP2112_PSTR_ATTR(serial,        CP2112_SERIAL_STRING);
1027
1028 #undef CP2112_PSTR_ATTR
1029
1030 static const struct attribute_group cp2112_attr_group = {
1031         .attrs = (struct attribute *[]){
1032                 &dev_attr_vendor_id.attr,
1033                 &dev_attr_product_id.attr,
1034                 &dev_attr_max_power.attr,
1035                 &dev_attr_power_mode.attr,
1036                 &dev_attr_release_version.attr,
1037                 &dev_attr_manufacturer.attr.attr,
1038                 &dev_attr_product.attr.attr,
1039                 &dev_attr_serial.attr.attr,
1040                 NULL
1041         }
1042 };
1043
1044 /* Chmoding our sysfs attributes is simply a way to expose which fields in the
1045  * PROM have already been programmed. We do not depend on this preventing
1046  * writing to these attributes since the CP2112 will simply ignore writes to
1047  * already-programmed fields. This is why there is no sense in fixing this
1048  * racy behaviour.
1049  */
1050 static void chmod_sysfs_attrs(struct hid_device *hdev)
1051 {
1052         struct attribute **attr;
1053         u8 buf[2];
1054         int ret;
1055
1056         ret = cp2112_hid_get(hdev, CP2112_LOCK_BYTE, buf, sizeof(buf),
1057                              HID_FEATURE_REPORT);
1058         if (ret != sizeof(buf)) {
1059                 hid_err(hdev, "error reading lock byte: %d\n", ret);
1060                 return;
1061         }
1062
1063         for (attr = cp2112_attr_group.attrs; *attr; ++attr) {
1064                 umode_t mode = (buf[1] & 1) ? S_IWUSR | S_IRUGO : S_IRUGO;
1065                 ret = sysfs_chmod_file(&hdev->dev.kobj, *attr, mode);
1066                 if (ret < 0)
1067                         hid_err(hdev, "error chmoding sysfs file %s\n",
1068                                 (*attr)->name);
1069                 buf[1] >>= 1;
1070         }
1071 }
1072
1073 static void cp2112_gpio_irq_ack(struct irq_data *d)
1074 {
1075 }
1076
1077 static void cp2112_gpio_irq_mask(struct irq_data *d)
1078 {
1079         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1080         struct cp2112_device *dev = gpiochip_get_data(gc);
1081
1082         __clear_bit(d->hwirq, &dev->irq_mask);
1083 }
1084
1085 static void cp2112_gpio_irq_unmask(struct irq_data *d)
1086 {
1087         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1088         struct cp2112_device *dev = gpiochip_get_data(gc);
1089
1090         __set_bit(d->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         u8 virqs = (u8)dev->irq_mask;
1100         u32 irq_type;
1101         int irq, virq, ret;
1102
1103         ret = cp2112_gpio_get_all(&dev->gc);
1104         if (ret == -ENODEV) /* the hardware has been disconnected */
1105                 return;
1106         if (ret < 0)
1107                 goto exit;
1108
1109         gpio_mask = ret;
1110
1111         while (virqs) {
1112                 virq = ffs(virqs) - 1;
1113                 virqs &= ~BIT(virq);
1114
1115                 if (!dev->gc.to_irq)
1116                         break;
1117
1118                 irq = dev->gc.to_irq(&dev->gc, virq);
1119
1120                 d = irq_get_irq_data(irq);
1121                 if (!d)
1122                         continue;
1123
1124                 irq_type = irqd_get_trigger_type(d);
1125
1126                 if (gpio_mask & BIT(virq)) {
1127                         /* Level High */
1128
1129                         if (irq_type & IRQ_TYPE_LEVEL_HIGH)
1130                                 handle_nested_irq(irq);
1131
1132                         if ((irq_type & IRQ_TYPE_EDGE_RISING) &&
1133                             !(dev->gpio_prev_state & BIT(virq)))
1134                                 handle_nested_irq(irq);
1135                 } else {
1136                         /* Level Low */
1137
1138                         if (irq_type & IRQ_TYPE_LEVEL_LOW)
1139                                 handle_nested_irq(irq);
1140
1141                         if ((irq_type & IRQ_TYPE_EDGE_FALLING) &&
1142                             (dev->gpio_prev_state & BIT(virq)))
1143                                 handle_nested_irq(irq);
1144                 }
1145         }
1146
1147         dev->gpio_prev_state = gpio_mask;
1148
1149 exit:
1150         if (dev->gpio_poll)
1151                 schedule_delayed_work(&dev->gpio_poll_worker, 10);
1152 }
1153
1154
1155 static unsigned int cp2112_gpio_irq_startup(struct irq_data *d)
1156 {
1157         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1158         struct cp2112_device *dev = gpiochip_get_data(gc);
1159
1160         if (!dev->gpio_poll) {
1161                 dev->gpio_poll = true;
1162                 schedule_delayed_work(&dev->gpio_poll_worker, 0);
1163         }
1164
1165         cp2112_gpio_irq_unmask(d);
1166         return 0;
1167 }
1168
1169 static void cp2112_gpio_irq_shutdown(struct irq_data *d)
1170 {
1171         struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1172         struct cp2112_device *dev = gpiochip_get_data(gc);
1173
1174         if (!dev->irq_mask) {
1175                 dev->gpio_poll = false;
1176                 cancel_delayed_work_sync(&dev->gpio_poll_worker);
1177         }
1178 }
1179
1180 static int cp2112_gpio_irq_type(struct irq_data *d, unsigned int type)
1181 {
1182         return 0;
1183 }
1184
1185 static int __maybe_unused cp2112_allocate_irq(struct cp2112_device *dev,
1186                                               int pin)
1187 {
1188         int ret;
1189
1190         if (dev->desc[pin])
1191                 return -EINVAL;
1192
1193         dev->desc[pin] = gpiochip_request_own_desc(&dev->gc, pin,
1194                                                    "HID/I2C:Event",
1195                                                    GPIO_ACTIVE_HIGH,
1196                                                    GPIOD_IN);
1197         if (IS_ERR(dev->desc[pin])) {
1198                 dev_err(dev->gc.parent, "Failed to request GPIO\n");
1199                 return PTR_ERR(dev->desc[pin]);
1200         }
1201
1202         ret = cp2112_gpio_direction_input(&dev->gc, pin);
1203         if (ret < 0) {
1204                 dev_err(dev->gc.parent, "Failed to set GPIO to input dir\n");
1205                 goto err_desc;
1206         }
1207
1208         ret = gpiochip_lock_as_irq(&dev->gc, pin);
1209         if (ret) {
1210                 dev_err(dev->gc.parent, "Failed to lock GPIO as interrupt\n");
1211                 goto err_desc;
1212         }
1213
1214         ret = gpiod_to_irq(dev->desc[pin]);
1215         if (ret < 0) {
1216                 dev_err(dev->gc.parent, "Failed to translate GPIO to IRQ\n");
1217                 goto err_lock;
1218         }
1219
1220         return ret;
1221
1222 err_lock:
1223         gpiochip_unlock_as_irq(&dev->gc, pin);
1224 err_desc:
1225         gpiochip_free_own_desc(dev->desc[pin]);
1226         dev->desc[pin] = NULL;
1227         return ret;
1228 }
1229
1230 static int cp2112_probe(struct hid_device *hdev, const struct hid_device_id *id)
1231 {
1232         struct cp2112_device *dev;
1233         u8 buf[3];
1234         struct cp2112_smbus_config_report config;
1235         struct gpio_irq_chip *girq;
1236         int ret;
1237
1238         dev = devm_kzalloc(&hdev->dev, sizeof(*dev), GFP_KERNEL);
1239         if (!dev)
1240                 return -ENOMEM;
1241
1242         dev->in_out_buffer = devm_kzalloc(&hdev->dev, CP2112_REPORT_MAX_LENGTH,
1243                                           GFP_KERNEL);
1244         if (!dev->in_out_buffer)
1245                 return -ENOMEM;
1246
1247         mutex_init(&dev->lock);
1248
1249         ret = hid_parse(hdev);
1250         if (ret) {
1251                 hid_err(hdev, "parse failed\n");
1252                 return ret;
1253         }
1254
1255         ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
1256         if (ret) {
1257                 hid_err(hdev, "hw start failed\n");
1258                 return ret;
1259         }
1260
1261         ret = hid_hw_open(hdev);
1262         if (ret) {
1263                 hid_err(hdev, "hw open failed\n");
1264                 goto err_hid_stop;
1265         }
1266
1267         ret = hid_hw_power(hdev, PM_HINT_FULLON);
1268         if (ret < 0) {
1269                 hid_err(hdev, "power management error: %d\n", ret);
1270                 goto err_hid_close;
1271         }
1272
1273         ret = cp2112_hid_get(hdev, CP2112_GET_VERSION_INFO, buf, sizeof(buf),
1274                              HID_FEATURE_REPORT);
1275         if (ret != sizeof(buf)) {
1276                 hid_err(hdev, "error requesting version\n");
1277                 if (ret >= 0)
1278                         ret = -EIO;
1279                 goto err_power_normal;
1280         }
1281
1282         hid_info(hdev, "Part Number: 0x%02X Device Version: 0x%02X\n",
1283                  buf[1], buf[2]);
1284
1285         ret = cp2112_hid_get(hdev, CP2112_SMBUS_CONFIG, (u8 *)&config,
1286                              sizeof(config), HID_FEATURE_REPORT);
1287         if (ret != sizeof(config)) {
1288                 hid_err(hdev, "error requesting SMBus config\n");
1289                 if (ret >= 0)
1290                         ret = -EIO;
1291                 goto err_power_normal;
1292         }
1293
1294         config.retry_time = cpu_to_be16(1);
1295
1296         ret = cp2112_hid_output(hdev, (u8 *)&config, sizeof(config),
1297                                 HID_FEATURE_REPORT);
1298         if (ret != sizeof(config)) {
1299                 hid_err(hdev, "error setting SMBus config\n");
1300                 if (ret >= 0)
1301                         ret = -EIO;
1302                 goto err_power_normal;
1303         }
1304
1305         hid_set_drvdata(hdev, (void *)dev);
1306         dev->hdev               = hdev;
1307         dev->adap.owner         = THIS_MODULE;
1308         dev->adap.class         = I2C_CLASS_HWMON;
1309         dev->adap.algo          = &smbus_algorithm;
1310         dev->adap.algo_data     = dev;
1311         dev->adap.dev.parent    = &hdev->dev;
1312         snprintf(dev->adap.name, sizeof(dev->adap.name),
1313                  "CP2112 SMBus Bridge on hidraw%d",
1314                  ((struct hidraw *)hdev->hidraw)->minor);
1315         dev->hwversion = buf[2];
1316         init_waitqueue_head(&dev->wait);
1317
1318         hid_device_io_start(hdev);
1319         ret = i2c_add_adapter(&dev->adap);
1320         hid_device_io_stop(hdev);
1321
1322         if (ret) {
1323                 hid_err(hdev, "error registering i2c adapter\n");
1324                 goto err_power_normal;
1325         }
1326
1327         hid_dbg(hdev, "adapter registered\n");
1328
1329         dev->gc.label                   = "cp2112_gpio";
1330         dev->gc.direction_input         = cp2112_gpio_direction_input;
1331         dev->gc.direction_output        = cp2112_gpio_direction_output;
1332         dev->gc.set                     = cp2112_gpio_set;
1333         dev->gc.get                     = cp2112_gpio_get;
1334         dev->gc.base                    = -1;
1335         dev->gc.ngpio                   = 8;
1336         dev->gc.can_sleep               = 1;
1337         dev->gc.parent                  = &hdev->dev;
1338
1339         dev->irq.name = "cp2112-gpio";
1340         dev->irq.irq_startup = cp2112_gpio_irq_startup;
1341         dev->irq.irq_shutdown = cp2112_gpio_irq_shutdown;
1342         dev->irq.irq_ack = cp2112_gpio_irq_ack;
1343         dev->irq.irq_mask = cp2112_gpio_irq_mask;
1344         dev->irq.irq_unmask = cp2112_gpio_irq_unmask;
1345         dev->irq.irq_set_type = cp2112_gpio_irq_type;
1346         dev->irq.flags = IRQCHIP_MASK_ON_SUSPEND;
1347
1348         girq = &dev->gc.irq;
1349         girq->chip = &dev->irq;
1350         /* The event comes from the outside so no parent handler */
1351         girq->parent_handler = NULL;
1352         girq->num_parents = 0;
1353         girq->parents = NULL;
1354         girq->default_type = IRQ_TYPE_NONE;
1355         girq->handler = handle_simple_irq;
1356         girq->threaded = true;
1357
1358         INIT_DELAYED_WORK(&dev->gpio_poll_worker, cp2112_gpio_poll_callback);
1359
1360         ret = gpiochip_add_data(&dev->gc, dev);
1361         if (ret < 0) {
1362                 hid_err(hdev, "error registering gpio chip\n");
1363                 goto err_free_i2c;
1364         }
1365
1366         ret = sysfs_create_group(&hdev->dev.kobj, &cp2112_attr_group);
1367         if (ret < 0) {
1368                 hid_err(hdev, "error creating sysfs attrs\n");
1369                 goto err_gpiochip_remove;
1370         }
1371
1372         chmod_sysfs_attrs(hdev);
1373         hid_hw_power(hdev, PM_HINT_NORMAL);
1374
1375         return ret;
1376
1377 err_gpiochip_remove:
1378         gpiochip_remove(&dev->gc);
1379 err_free_i2c:
1380         i2c_del_adapter(&dev->adap);
1381 err_power_normal:
1382         hid_hw_power(hdev, PM_HINT_NORMAL);
1383 err_hid_close:
1384         hid_hw_close(hdev);
1385 err_hid_stop:
1386         hid_hw_stop(hdev);
1387         return ret;
1388 }
1389
1390 static void cp2112_remove(struct hid_device *hdev)
1391 {
1392         struct cp2112_device *dev = hid_get_drvdata(hdev);
1393         int i;
1394
1395         sysfs_remove_group(&hdev->dev.kobj, &cp2112_attr_group);
1396         i2c_del_adapter(&dev->adap);
1397
1398         if (dev->gpio_poll) {
1399                 dev->gpio_poll = false;
1400                 cancel_delayed_work_sync(&dev->gpio_poll_worker);
1401         }
1402
1403         for (i = 0; i < ARRAY_SIZE(dev->desc); i++) {
1404                 gpiochip_unlock_as_irq(&dev->gc, i);
1405                 gpiochip_free_own_desc(dev->desc[i]);
1406         }
1407
1408         gpiochip_remove(&dev->gc);
1409         /* i2c_del_adapter has finished removing all i2c devices from our
1410          * adapter. Well behaved devices should no longer call our cp2112_xfer
1411          * and should have waited for any pending calls to finish. It has also
1412          * waited for device_unregister(&adap->dev) to complete. Therefore we
1413          * can safely free our struct cp2112_device.
1414          */
1415         hid_hw_close(hdev);
1416         hid_hw_stop(hdev);
1417 }
1418
1419 static int cp2112_raw_event(struct hid_device *hdev, struct hid_report *report,
1420                             u8 *data, int size)
1421 {
1422         struct cp2112_device *dev = hid_get_drvdata(hdev);
1423         struct cp2112_xfer_status_report *xfer = (void *)data;
1424
1425         switch (data[0]) {
1426         case CP2112_TRANSFER_STATUS_RESPONSE:
1427                 hid_dbg(hdev, "xfer status: %02x %02x %04x %04x\n",
1428                         xfer->status0, xfer->status1,
1429                         be16_to_cpu(xfer->retries), be16_to_cpu(xfer->length));
1430
1431                 switch (xfer->status0) {
1432                 case STATUS0_IDLE:
1433                         dev->xfer_status = -EAGAIN;
1434                         break;
1435                 case STATUS0_BUSY:
1436                         dev->xfer_status = -EBUSY;
1437                         break;
1438                 case STATUS0_COMPLETE:
1439                         dev->xfer_status = be16_to_cpu(xfer->length);
1440                         break;
1441                 case STATUS0_ERROR:
1442                         switch (xfer->status1) {
1443                         case STATUS1_TIMEOUT_NACK:
1444                         case STATUS1_TIMEOUT_BUS:
1445                                 dev->xfer_status = -ETIMEDOUT;
1446                                 break;
1447                         default:
1448                                 dev->xfer_status = -EIO;
1449                                 break;
1450                         }
1451                         break;
1452                 default:
1453                         dev->xfer_status = -EINVAL;
1454                         break;
1455                 }
1456
1457                 atomic_set(&dev->xfer_avail, 1);
1458                 break;
1459         case CP2112_DATA_READ_RESPONSE:
1460                 hid_dbg(hdev, "read response: %02x %02x\n", data[1], data[2]);
1461
1462                 dev->read_length = data[2];
1463                 if (dev->read_length > sizeof(dev->read_data))
1464                         dev->read_length = sizeof(dev->read_data);
1465
1466                 memcpy(dev->read_data, &data[3], dev->read_length);
1467                 atomic_set(&dev->read_avail, 1);
1468                 break;
1469         default:
1470                 hid_err(hdev, "unknown report\n");
1471
1472                 return 0;
1473         }
1474
1475         wake_up_interruptible(&dev->wait);
1476         return 1;
1477 }
1478
1479 static struct hid_driver cp2112_driver = {
1480         .name           = "cp2112",
1481         .id_table       = cp2112_devices,
1482         .probe          = cp2112_probe,
1483         .remove         = cp2112_remove,
1484         .raw_event      = cp2112_raw_event,
1485 };
1486
1487 module_hid_driver(cp2112_driver);
1488 MODULE_DESCRIPTION("Silicon Labs HID USB to SMBus master bridge");
1489 MODULE_AUTHOR("David Barksdale <dbarksdale@uplogix.com>");
1490 MODULE_LICENSE("GPL");
1491