linux/drivers/hid/hid-cp2112.c
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   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 *   http://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
  35enum {
  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
  56enum {
  57        STATUS0_IDLE            = 0x00,
  58        STATUS0_BUSY            = 0x01,
  59        STATUS0_COMPLETE        = 0x02,
  60        STATUS0_ERROR           = 0x03,
  61};
  62
  63enum {
  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
  72struct 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
  83struct 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
  96struct cp2112_read_req_report {
  97        u8 report;      /* CP2112_DATA_READ_REQUEST */
  98        u8 slave_address;
  99        __be16 length;
 100} __packed;
 101
 102struct 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
 110struct 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
 117struct cp2112_force_read_report {
 118        u8 report;      /* CP2112_DATA_READ_FORCE_SEND */
 119        __be16 length;
 120} __packed;
 121
 122struct 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
 130struct 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. */
 141static 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. */
 145static const int RESPONSE_TIMEOUT = 50;
 146
 147static const struct hid_device_id cp2112_devices[] = {
 148        { HID_USB_DEVICE(USB_VENDOR_ID_CYGNAL, USB_DEVICE_ID_CYGNAL_CP2112) },
 149        { }
 150};
 151MODULE_DEVICE_TABLE(hid, cp2112_devices);
 152
 153struct 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        u8 *in_out_buffer;
 165        struct mutex lock;
 166
 167        struct gpio_desc *desc[8];
 168        bool gpio_poll;
 169        struct delayed_work gpio_poll_worker;
 170        unsigned long irq_mask;
 171        u8 gpio_prev_state;
 172};
 173
 174static int gpio_push_pull = 0xFF;
 175module_param(gpio_push_pull, int, S_IRUGO | S_IWUSR);
 176MODULE_PARM_DESC(gpio_push_pull, "GPIO push-pull configuration bitmask");
 177
 178static int cp2112_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 179{
 180        struct cp2112_device *dev = gpiochip_get_data(chip);
 181        struct hid_device *hdev = dev->hdev;
 182        u8 *buf = dev->in_out_buffer;
 183        int ret;
 184
 185        mutex_lock(&dev->lock);
 186
 187        ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
 188                                 CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
 189                                 HID_REQ_GET_REPORT);
 190        if (ret != CP2112_GPIO_CONFIG_LENGTH) {
 191                hid_err(hdev, "error requesting GPIO config: %d\n", ret);
 192                if (ret >= 0)
 193                        ret = -EIO;
 194                goto exit;
 195        }
 196
 197        buf[1] &= ~(1 << offset);
 198        buf[2] = gpio_push_pull;
 199
 200        ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
 201                                 CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
 202                                 HID_REQ_SET_REPORT);
 203        if (ret != CP2112_GPIO_CONFIG_LENGTH) {
 204                hid_err(hdev, "error setting GPIO config: %d\n", ret);
 205                if (ret >= 0)
 206                        ret = -EIO;
 207                goto exit;
 208        }
 209
 210        ret = 0;
 211
 212exit:
 213        mutex_unlock(&dev->lock);
 214        return ret;
 215}
 216
 217static void cp2112_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 218{
 219        struct cp2112_device *dev = gpiochip_get_data(chip);
 220        struct hid_device *hdev = dev->hdev;
 221        u8 *buf = dev->in_out_buffer;
 222        int ret;
 223
 224        mutex_lock(&dev->lock);
 225
 226        buf[0] = CP2112_GPIO_SET;
 227        buf[1] = value ? 0xff : 0;
 228        buf[2] = 1 << offset;
 229
 230        ret = hid_hw_raw_request(hdev, CP2112_GPIO_SET, buf,
 231                                 CP2112_GPIO_SET_LENGTH, HID_FEATURE_REPORT,
 232                                 HID_REQ_SET_REPORT);
 233        if (ret < 0)
 234                hid_err(hdev, "error setting GPIO values: %d\n", ret);
 235
 236        mutex_unlock(&dev->lock);
 237}
 238
 239static int cp2112_gpio_get_all(struct gpio_chip *chip)
 240{
 241        struct cp2112_device *dev = gpiochip_get_data(chip);
 242        struct hid_device *hdev = dev->hdev;
 243        u8 *buf = dev->in_out_buffer;
 244        int ret;
 245
 246        mutex_lock(&dev->lock);
 247
 248        ret = hid_hw_raw_request(hdev, CP2112_GPIO_GET, buf,
 249                                 CP2112_GPIO_GET_LENGTH, HID_FEATURE_REPORT,
 250                                 HID_REQ_GET_REPORT);
 251        if (ret != CP2112_GPIO_GET_LENGTH) {
 252                hid_err(hdev, "error requesting GPIO values: %d\n", ret);
 253                ret = ret < 0 ? ret : -EIO;
 254                goto exit;
 255        }
 256
 257        ret = buf[1];
 258
 259exit:
 260        mutex_unlock(&dev->lock);
 261
 262        return ret;
 263}
 264
 265static int cp2112_gpio_get(struct gpio_chip *chip, unsigned int offset)
 266{
 267        int ret;
 268
 269        ret = cp2112_gpio_get_all(chip);
 270        if (ret < 0)
 271                return ret;
 272
 273        return (ret >> offset) & 1;
 274}
 275
 276static int cp2112_gpio_direction_output(struct gpio_chip *chip,
 277                                        unsigned offset, int value)
 278{
 279        struct cp2112_device *dev = gpiochip_get_data(chip);
 280        struct hid_device *hdev = dev->hdev;
 281        u8 *buf = dev->in_out_buffer;
 282        int ret;
 283
 284        mutex_lock(&dev->lock);
 285
 286        ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
 287                                 CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
 288                                 HID_REQ_GET_REPORT);
 289        if (ret != CP2112_GPIO_CONFIG_LENGTH) {
 290                hid_err(hdev, "error requesting GPIO config: %d\n", ret);
 291                goto fail;
 292        }
 293
 294        buf[1] |= 1 << offset;
 295        buf[2] = gpio_push_pull;
 296
 297        ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
 298                                 CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
 299                                 HID_REQ_SET_REPORT);
 300        if (ret < 0) {
 301                hid_err(hdev, "error setting GPIO config: %d\n", ret);
 302                goto fail;
 303        }
 304
 305        mutex_unlock(&dev->lock);
 306
 307        /*
 308         * Set gpio value when output direction is already set,
 309         * as specified in AN495, Rev. 0.2, cpt. 4.4
 310         */
 311        cp2112_gpio_set(chip, offset, value);
 312
 313        return 0;
 314
 315fail:
 316        mutex_unlock(&dev->lock);
 317        return ret < 0 ? ret : -EIO;
 318}
 319
 320static int cp2112_hid_get(struct hid_device *hdev, unsigned char report_number,
 321                          u8 *data, size_t count, unsigned char report_type)
 322{
 323        u8 *buf;
 324        int ret;
 325
 326        buf = kmalloc(count, GFP_KERNEL);
 327        if (!buf)
 328                return -ENOMEM;
 329
 330        ret = hid_hw_raw_request(hdev, report_number, buf, count,
 331                                       report_type, HID_REQ_GET_REPORT);
 332        memcpy(data, buf, count);
 333        kfree(buf);
 334        return ret;
 335}
 336
 337static int cp2112_hid_output(struct hid_device *hdev, u8 *data, size_t count,
 338                             unsigned char report_type)
 339{
 340        u8 *buf;
 341        int ret;
 342
 343        buf = kmemdup(data, count, GFP_KERNEL);
 344        if (!buf)
 345                return -ENOMEM;
 346
 347        if (report_type == HID_OUTPUT_REPORT)
 348                ret = hid_hw_output_report(hdev, buf, count);
 349        else
 350                ret = hid_hw_raw_request(hdev, buf[0], buf, count, report_type,
 351                                HID_REQ_SET_REPORT);
 352
 353        kfree(buf);
 354        return ret;
 355}
 356
 357static int cp2112_wait(struct cp2112_device *dev, atomic_t *avail)
 358{
 359        int ret = 0;
 360
 361        /* We have sent either a CP2112_TRANSFER_STATUS_REQUEST or a
 362         * CP2112_DATA_READ_FORCE_SEND and we are waiting for the response to
 363         * come in cp2112_raw_event or timeout. There will only be one of these
 364         * in flight at any one time. The timeout is extremely large and is a
 365         * last resort if the CP2112 has died. If we do timeout we don't expect
 366         * to receive the response which would cause data races, it's not like
 367         * we can do anything about it anyway.
 368         */
 369        ret = wait_event_interruptible_timeout(dev->wait,
 370                atomic_read(avail), msecs_to_jiffies(RESPONSE_TIMEOUT));
 371        if (-ERESTARTSYS == ret)
 372                return ret;
 373        if (!ret)
 374                return -ETIMEDOUT;
 375
 376        atomic_set(avail, 0);
 377        return 0;
 378}
 379
 380static int cp2112_xfer_status(struct cp2112_device *dev)
 381{
 382        struct hid_device *hdev = dev->hdev;
 383        u8 buf[2];
 384        int ret;
 385
 386        buf[0] = CP2112_TRANSFER_STATUS_REQUEST;
 387        buf[1] = 0x01;
 388        atomic_set(&dev->xfer_avail, 0);
 389
 390        ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
 391        if (ret < 0) {
 392                hid_warn(hdev, "Error requesting status: %d\n", ret);
 393                return ret;
 394        }
 395
 396        ret = cp2112_wait(dev, &dev->xfer_avail);
 397        if (ret)
 398                return ret;
 399
 400        return dev->xfer_status;
 401}
 402
 403static int cp2112_read(struct cp2112_device *dev, u8 *data, size_t size)
 404{
 405        struct hid_device *hdev = dev->hdev;
 406        struct cp2112_force_read_report report;
 407        int ret;
 408
 409        if (size > sizeof(dev->read_data))
 410                size = sizeof(dev->read_data);
 411        report.report = CP2112_DATA_READ_FORCE_SEND;
 412        report.length = cpu_to_be16(size);
 413
 414        atomic_set(&dev->read_avail, 0);
 415
 416        ret = cp2112_hid_output(hdev, &report.report, sizeof(report),
 417                                HID_OUTPUT_REPORT);
 418        if (ret < 0) {
 419                hid_warn(hdev, "Error requesting data: %d\n", ret);
 420                return ret;
 421        }
 422
 423        ret = cp2112_wait(dev, &dev->read_avail);
 424        if (ret)
 425                return ret;
 426
 427        hid_dbg(hdev, "read %d of %zd bytes requested\n",
 428                dev->read_length, size);
 429
 430        if (size > dev->read_length)
 431                size = dev->read_length;
 432
 433        memcpy(data, dev->read_data, size);
 434        return dev->read_length;
 435}
 436
 437static int cp2112_read_req(void *buf, u8 slave_address, u16 length)
 438{
 439        struct cp2112_read_req_report *report = buf;
 440
 441        if (length < 1 || length > 512)
 442                return -EINVAL;
 443
 444        report->report = CP2112_DATA_READ_REQUEST;
 445        report->slave_address = slave_address << 1;
 446        report->length = cpu_to_be16(length);
 447        return sizeof(*report);
 448}
 449
 450static int cp2112_write_read_req(void *buf, u8 slave_address, u16 length,
 451                                 u8 command, u8 *data, u8 data_length)
 452{
 453        struct cp2112_write_read_req_report *report = buf;
 454
 455        if (length < 1 || length > 512
 456            || data_length > sizeof(report->target_address) - 1)
 457                return -EINVAL;
 458
 459        report->report = CP2112_DATA_WRITE_READ_REQUEST;
 460        report->slave_address = slave_address << 1;
 461        report->length = cpu_to_be16(length);
 462        report->target_address_length = data_length + 1;
 463        report->target_address[0] = command;
 464        memcpy(&report->target_address[1], data, data_length);
 465        return data_length + 6;
 466}
 467
 468static int cp2112_write_req(void *buf, u8 slave_address, u8 command, u8 *data,
 469                            u8 data_length)
 470{
 471        struct cp2112_write_req_report *report = buf;
 472
 473        if (data_length > sizeof(report->data) - 1)
 474                return -EINVAL;
 475
 476        report->report = CP2112_DATA_WRITE_REQUEST;
 477        report->slave_address = slave_address << 1;
 478        report->length = data_length + 1;
 479        report->data[0] = command;
 480        memcpy(&report->data[1], data, data_length);
 481        return data_length + 4;
 482}
 483
 484static int cp2112_i2c_write_req(void *buf, u8 slave_address, u8 *data,
 485                                u8 data_length)
 486{
 487        struct cp2112_write_req_report *report = buf;
 488
 489        if (data_length > sizeof(report->data))
 490                return -EINVAL;
 491
 492        report->report = CP2112_DATA_WRITE_REQUEST;
 493        report->slave_address = slave_address << 1;
 494        report->length = data_length;
 495        memcpy(report->data, data, data_length);
 496        return data_length + 3;
 497}
 498
 499static int cp2112_i2c_write_read_req(void *buf, u8 slave_address,
 500                                     u8 *addr, int addr_length,
 501                                     int read_length)
 502{
 503        struct cp2112_write_read_req_report *report = buf;
 504
 505        if (read_length < 1 || read_length > 512 ||
 506            addr_length > sizeof(report->target_address))
 507                return -EINVAL;
 508
 509        report->report = CP2112_DATA_WRITE_READ_REQUEST;
 510        report->slave_address = slave_address << 1;
 511        report->length = cpu_to_be16(read_length);
 512        report->target_address_length = addr_length;
 513        memcpy(report->target_address, addr, addr_length);
 514        return addr_length + 5;
 515}
 516
 517static int cp2112_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs,
 518                           int num)
 519{
 520        struct cp2112_device *dev = (struct cp2112_device *)adap->algo_data;
 521        struct hid_device *hdev = dev->hdev;
 522        u8 buf[64];
 523        ssize_t count;
 524        ssize_t read_length = 0;
 525        u8 *read_buf = NULL;
 526        unsigned int retries;
 527        int ret;
 528
 529        hid_dbg(hdev, "I2C %d messages\n", num);
 530
 531        if (num == 1) {
 532                if (msgs->flags & I2C_M_RD) {
 533                        hid_dbg(hdev, "I2C read %#04x len %d\n",
 534                                msgs->addr, msgs->len);
 535                        read_length = msgs->len;
 536                        read_buf = msgs->buf;
 537                        count = cp2112_read_req(buf, msgs->addr, msgs->len);
 538                } else {
 539                        hid_dbg(hdev, "I2C write %#04x len %d\n",
 540                                msgs->addr, msgs->len);
 541                        count = cp2112_i2c_write_req(buf, msgs->addr,
 542                                                     msgs->buf, msgs->len);
 543                }
 544                if (count < 0)
 545                        return count;
 546        } else if (dev->hwversion > 1 &&  /* no repeated start in rev 1 */
 547                   num == 2 &&
 548                   msgs[0].addr == msgs[1].addr &&
 549                   !(msgs[0].flags & I2C_M_RD) && (msgs[1].flags & I2C_M_RD)) {
 550                hid_dbg(hdev, "I2C write-read %#04x wlen %d rlen %d\n",
 551                        msgs[0].addr, msgs[0].len, msgs[1].len);
 552                read_length = msgs[1].len;
 553                read_buf = msgs[1].buf;
 554                count = cp2112_i2c_write_read_req(buf, msgs[0].addr,
 555                                msgs[0].buf, msgs[0].len, msgs[1].len);
 556                if (count < 0)
 557                        return count;
 558        } else {
 559                hid_err(hdev,
 560                        "Multi-message I2C transactions not supported\n");
 561                return -EOPNOTSUPP;
 562        }
 563
 564        ret = hid_hw_power(hdev, PM_HINT_FULLON);
 565        if (ret < 0) {
 566                hid_err(hdev, "power management error: %d\n", ret);
 567                return ret;
 568        }
 569
 570        ret = cp2112_hid_output(hdev, buf, count, HID_OUTPUT_REPORT);
 571        if (ret < 0) {
 572                hid_warn(hdev, "Error starting transaction: %d\n", ret);
 573                goto power_normal;
 574        }
 575
 576        for (retries = 0; retries < XFER_STATUS_RETRIES; ++retries) {
 577                ret = cp2112_xfer_status(dev);
 578                if (-EBUSY == ret)
 579                        continue;
 580                if (ret < 0)
 581                        goto power_normal;
 582                break;
 583        }
 584
 585        if (XFER_STATUS_RETRIES <= retries) {
 586                hid_warn(hdev, "Transfer timed out, cancelling.\n");
 587                buf[0] = CP2112_CANCEL_TRANSFER;
 588                buf[1] = 0x01;
 589
 590                ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
 591                if (ret < 0)
 592                        hid_warn(hdev, "Error cancelling transaction: %d\n",
 593                                 ret);
 594
 595                ret = -ETIMEDOUT;
 596                goto power_normal;
 597        }
 598
 599        for (count = 0; count < read_length;) {
 600                ret = cp2112_read(dev, read_buf + count, read_length - count);
 601                if (ret < 0)
 602                        goto power_normal;
 603                if (ret == 0) {
 604                        hid_err(hdev, "read returned 0\n");
 605                        ret = -EIO;
 606                        goto power_normal;
 607                }
 608                count += ret;
 609                if (count > read_length) {
 610                        /*
 611                         * The hardware returned too much data.
 612                         * This is mostly harmless because cp2112_read()
 613                         * has a limit check so didn't overrun our
 614                         * buffer.  Nevertheless, we return an error
 615                         * because something is seriously wrong and
 616                         * it shouldn't go unnoticed.
 617                         */
 618                        hid_err(hdev, "long read: %d > %zd\n",
 619                                ret, read_length - count + ret);
 620                        ret = -EIO;
 621                        goto power_normal;
 622                }
 623        }
 624
 625        /* return the number of transferred messages */
 626        ret = num;
 627
 628power_normal:
 629        hid_hw_power(hdev, PM_HINT_NORMAL);
 630        hid_dbg(hdev, "I2C transfer finished: %d\n", ret);
 631        return ret;
 632}
 633
 634static int cp2112_xfer(struct i2c_adapter *adap, u16 addr,
 635                       unsigned short flags, char read_write, u8 command,
 636                       int size, union i2c_smbus_data *data)
 637{
 638        struct cp2112_device *dev = (struct cp2112_device *)adap->algo_data;
 639        struct hid_device *hdev = dev->hdev;
 640        u8 buf[64];
 641        __le16 word;
 642        ssize_t count;
 643        size_t read_length = 0;
 644        unsigned int retries;
 645        int ret;
 646
 647        hid_dbg(hdev, "%s addr 0x%x flags 0x%x cmd 0x%x size %d\n",
 648                read_write == I2C_SMBUS_WRITE ? "write" : "read",
 649                addr, flags, command, size);
 650
 651        switch (size) {
 652        case I2C_SMBUS_BYTE:
 653                read_length = 1;
 654
 655                if (I2C_SMBUS_READ == read_write)
 656                        count = cp2112_read_req(buf, addr, read_length);
 657                else
 658                        count = cp2112_write_req(buf, addr, command, NULL,
 659                                                 0);
 660                break;
 661        case I2C_SMBUS_BYTE_DATA:
 662                read_length = 1;
 663
 664                if (I2C_SMBUS_READ == read_write)
 665                        count = cp2112_write_read_req(buf, addr, read_length,
 666                                                      command, NULL, 0);
 667                else
 668                        count = cp2112_write_req(buf, addr, command,
 669                                                 &data->byte, 1);
 670                break;
 671        case I2C_SMBUS_WORD_DATA:
 672                read_length = 2;
 673                word = cpu_to_le16(data->word);
 674
 675                if (I2C_SMBUS_READ == read_write)
 676                        count = cp2112_write_read_req(buf, addr, read_length,
 677                                                      command, NULL, 0);
 678                else
 679                        count = cp2112_write_req(buf, addr, command,
 680                                                 (u8 *)&word, 2);
 681                break;
 682        case I2C_SMBUS_PROC_CALL:
 683                size = I2C_SMBUS_WORD_DATA;
 684                read_write = I2C_SMBUS_READ;
 685                read_length = 2;
 686                word = cpu_to_le16(data->word);
 687
 688                count = cp2112_write_read_req(buf, addr, read_length, command,
 689                                              (u8 *)&word, 2);
 690                break;
 691        case I2C_SMBUS_I2C_BLOCK_DATA:
 692                if (read_write == I2C_SMBUS_READ) {
 693                        read_length = data->block[0];
 694                        count = cp2112_write_read_req(buf, addr, read_length,
 695                                                      command, NULL, 0);
 696                } else {
 697                        count = cp2112_write_req(buf, addr, command,
 698                                                 data->block + 1,
 699                                                 data->block[0]);
 700                }
 701                break;
 702        case I2C_SMBUS_BLOCK_DATA:
 703                if (I2C_SMBUS_READ == read_write) {
 704                        count = cp2112_write_read_req(buf, addr,
 705                                                      I2C_SMBUS_BLOCK_MAX,
 706                                                      command, NULL, 0);
 707                } else {
 708                        count = cp2112_write_req(buf, addr, command,
 709                                                 data->block,
 710                                                 data->block[0] + 1);
 711                }
 712                break;
 713        case I2C_SMBUS_BLOCK_PROC_CALL:
 714                size = I2C_SMBUS_BLOCK_DATA;
 715                read_write = I2C_SMBUS_READ;
 716
 717                count = cp2112_write_read_req(buf, addr, I2C_SMBUS_BLOCK_MAX,
 718                                              command, data->block,
 719                                              data->block[0] + 1);
 720                break;
 721        default:
 722                hid_warn(hdev, "Unsupported transaction %d\n", size);
 723                return -EOPNOTSUPP;
 724        }
 725
 726        if (count < 0)
 727                return count;
 728
 729        ret = hid_hw_power(hdev, PM_HINT_FULLON);
 730        if (ret < 0) {
 731                hid_err(hdev, "power management error: %d\n", ret);
 732                return ret;
 733        }
 734
 735        ret = cp2112_hid_output(hdev, buf, count, HID_OUTPUT_REPORT);
 736        if (ret < 0) {
 737                hid_warn(hdev, "Error starting transaction: %d\n", ret);
 738                goto power_normal;
 739        }
 740
 741        for (retries = 0; retries < XFER_STATUS_RETRIES; ++retries) {
 742                ret = cp2112_xfer_status(dev);
 743                if (-EBUSY == ret)
 744                        continue;
 745                if (ret < 0)
 746                        goto power_normal;
 747                break;
 748        }
 749
 750        if (XFER_STATUS_RETRIES <= retries) {
 751                hid_warn(hdev, "Transfer timed out, cancelling.\n");
 752                buf[0] = CP2112_CANCEL_TRANSFER;
 753                buf[1] = 0x01;
 754
 755                ret = cp2112_hid_output(hdev, buf, 2, HID_OUTPUT_REPORT);
 756                if (ret < 0)
 757                        hid_warn(hdev, "Error cancelling transaction: %d\n",
 758                                 ret);
 759
 760                ret = -ETIMEDOUT;
 761                goto power_normal;
 762        }
 763
 764        if (I2C_SMBUS_WRITE == read_write) {
 765                ret = 0;
 766                goto power_normal;
 767        }
 768
 769        if (I2C_SMBUS_BLOCK_DATA == size)
 770                read_length = ret;
 771
 772        ret = cp2112_read(dev, buf, read_length);
 773        if (ret < 0)
 774                goto power_normal;
 775        if (ret != read_length) {
 776                hid_warn(hdev, "short read: %d < %zd\n", ret, read_length);
 777                ret = -EIO;
 778                goto power_normal;
 779        }
 780
 781        switch (size) {
 782        case I2C_SMBUS_BYTE:
 783        case I2C_SMBUS_BYTE_DATA:
 784                data->byte = buf[0];
 785                break;
 786        case I2C_SMBUS_WORD_DATA:
 787                data->word = le16_to_cpup((__le16 *)buf);
 788                break;
 789        case I2C_SMBUS_I2C_BLOCK_DATA:
 790                memcpy(data->block + 1, buf, read_length);
 791                break;
 792        case I2C_SMBUS_BLOCK_DATA:
 793                if (read_length > I2C_SMBUS_BLOCK_MAX) {
 794                        ret = -EPROTO;
 795                        goto power_normal;
 796                }
 797
 798                memcpy(data->block, buf, read_length);
 799                break;
 800        }
 801
 802        ret = 0;
 803power_normal:
 804        hid_hw_power(hdev, PM_HINT_NORMAL);
 805        hid_dbg(hdev, "transfer finished: %d\n", ret);
 806        return ret;
 807}
 808
 809static u32 cp2112_functionality(struct i2c_adapter *adap)
 810{
 811        return I2C_FUNC_I2C |
 812                I2C_FUNC_SMBUS_BYTE |
 813                I2C_FUNC_SMBUS_BYTE_DATA |
 814                I2C_FUNC_SMBUS_WORD_DATA |
 815                I2C_FUNC_SMBUS_BLOCK_DATA |
 816                I2C_FUNC_SMBUS_I2C_BLOCK |
 817                I2C_FUNC_SMBUS_PROC_CALL |
 818                I2C_FUNC_SMBUS_BLOCK_PROC_CALL;
 819}
 820
 821static const struct i2c_algorithm smbus_algorithm = {
 822        .master_xfer    = cp2112_i2c_xfer,
 823        .smbus_xfer     = cp2112_xfer,
 824        .functionality  = cp2112_functionality,
 825};
 826
 827static int cp2112_get_usb_config(struct hid_device *hdev,
 828                                 struct cp2112_usb_config_report *cfg)
 829{
 830        int ret;
 831
 832        ret = cp2112_hid_get(hdev, CP2112_USB_CONFIG, (u8 *)cfg, sizeof(*cfg),
 833                             HID_FEATURE_REPORT);
 834        if (ret != sizeof(*cfg)) {
 835                hid_err(hdev, "error reading usb config: %d\n", ret);
 836                if (ret < 0)
 837                        return ret;
 838                return -EIO;
 839        }
 840
 841        return 0;
 842}
 843
 844static int cp2112_set_usb_config(struct hid_device *hdev,
 845                                 struct cp2112_usb_config_report *cfg)
 846{
 847        int ret;
 848
 849        BUG_ON(cfg->report != CP2112_USB_CONFIG);
 850
 851        ret = cp2112_hid_output(hdev, (u8 *)cfg, sizeof(*cfg),
 852                                HID_FEATURE_REPORT);
 853        if (ret != sizeof(*cfg)) {
 854                hid_err(hdev, "error writing usb config: %d\n", ret);
 855                if (ret < 0)
 856                        return ret;
 857                return -EIO;
 858        }
 859
 860        return 0;
 861}
 862
 863static void chmod_sysfs_attrs(struct hid_device *hdev);
 864
 865#define CP2112_CONFIG_ATTR(name, store, format, ...) \
 866static ssize_t name##_store(struct device *kdev, \
 867                            struct device_attribute *attr, const char *buf, \
 868                            size_t count) \
 869{ \
 870        struct hid_device *hdev = to_hid_device(kdev); \
 871        struct cp2112_usb_config_report cfg; \
 872        int ret = cp2112_get_usb_config(hdev, &cfg); \
 873        if (ret) \
 874                return ret; \
 875        store; \
 876        ret = cp2112_set_usb_config(hdev, &cfg); \
 877        if (ret) \
 878                return ret; \
 879        chmod_sysfs_attrs(hdev); \
 880        return count; \
 881} \
 882static ssize_t name##_show(struct device *kdev, \
 883                           struct device_attribute *attr, char *buf) \
 884{ \
 885        struct hid_device *hdev = to_hid_device(kdev); \
 886        struct cp2112_usb_config_report cfg; \
 887        int ret = cp2112_get_usb_config(hdev, &cfg); \
 888        if (ret) \
 889                return ret; \
 890        return scnprintf(buf, PAGE_SIZE, format, ##__VA_ARGS__); \
 891} \
 892static DEVICE_ATTR_RW(name);
 893
 894CP2112_CONFIG_ATTR(vendor_id, ({
 895        u16 vid;
 896
 897        if (sscanf(buf, "%hi", &vid) != 1)
 898                return -EINVAL;
 899
 900        cfg.vid = cpu_to_le16(vid);
 901        cfg.mask = 0x01;
 902}), "0x%04x\n", le16_to_cpu(cfg.vid));
 903
 904CP2112_CONFIG_ATTR(product_id, ({
 905        u16 pid;
 906
 907        if (sscanf(buf, "%hi", &pid) != 1)
 908                return -EINVAL;
 909
 910        cfg.pid = cpu_to_le16(pid);
 911        cfg.mask = 0x02;
 912}), "0x%04x\n", le16_to_cpu(cfg.pid));
 913
 914CP2112_CONFIG_ATTR(max_power, ({
 915        int mA;
 916
 917        if (sscanf(buf, "%i", &mA) != 1)
 918                return -EINVAL;
 919
 920        cfg.max_power = (mA + 1) / 2;
 921        cfg.mask = 0x04;
 922}), "%u mA\n", cfg.max_power * 2);
 923
 924CP2112_CONFIG_ATTR(power_mode, ({
 925        if (sscanf(buf, "%hhi", &cfg.power_mode) != 1)
 926                return -EINVAL;
 927
 928        cfg.mask = 0x08;
 929}), "%u\n", cfg.power_mode);
 930
 931CP2112_CONFIG_ATTR(release_version, ({
 932        if (sscanf(buf, "%hhi.%hhi", &cfg.release_major, &cfg.release_minor)
 933            != 2)
 934                return -EINVAL;
 935
 936        cfg.mask = 0x10;
 937}), "%u.%u\n", cfg.release_major, cfg.release_minor);
 938
 939#undef CP2112_CONFIG_ATTR
 940
 941struct cp2112_pstring_attribute {
 942        struct device_attribute attr;
 943        unsigned char report;
 944};
 945
 946static ssize_t pstr_store(struct device *kdev,
 947                          struct device_attribute *kattr, const char *buf,
 948                          size_t count)
 949{
 950        struct hid_device *hdev = to_hid_device(kdev);
 951        struct cp2112_pstring_attribute *attr =
 952                container_of(kattr, struct cp2112_pstring_attribute, attr);
 953        struct cp2112_string_report report;
 954        int ret;
 955
 956        memset(&report, 0, sizeof(report));
 957
 958        ret = utf8s_to_utf16s(buf, count, UTF16_LITTLE_ENDIAN,
 959                              report.string, ARRAY_SIZE(report.string));
 960        report.report = attr->report;
 961        report.length = ret * sizeof(report.string[0]) + 2;
 962        report.type = USB_DT_STRING;
 963
 964        ret = cp2112_hid_output(hdev, &report.report, report.length + 1,
 965                                HID_FEATURE_REPORT);
 966        if (ret != report.length + 1) {
 967                hid_err(hdev, "error writing %s string: %d\n", kattr->attr.name,
 968                        ret);
 969                if (ret < 0)
 970                        return ret;
 971                return -EIO;
 972        }
 973
 974        chmod_sysfs_attrs(hdev);
 975        return count;
 976}
 977
 978static ssize_t pstr_show(struct device *kdev,
 979                         struct device_attribute *kattr, char *buf)
 980{
 981        struct hid_device *hdev = to_hid_device(kdev);
 982        struct cp2112_pstring_attribute *attr =
 983                container_of(kattr, struct cp2112_pstring_attribute, attr);
 984        struct cp2112_string_report report;
 985        u8 length;
 986        int ret;
 987
 988        ret = cp2112_hid_get(hdev, attr->report, &report.report,
 989                             sizeof(report) - 1, HID_FEATURE_REPORT);
 990        if (ret < 3) {
 991                hid_err(hdev, "error reading %s string: %d\n", kattr->attr.name,
 992                        ret);
 993                if (ret < 0)
 994                        return ret;
 995                return -EIO;
 996        }
 997
 998        if (report.length < 2) {
 999                hid_err(hdev, "invalid %s string length: %d\n",
1000                        kattr->attr.name, report.length);
1001                return -EIO;
1002        }
1003
1004        length = report.length > ret - 1 ? ret - 1 : report.length;
1005        length = (length - 2) / sizeof(report.string[0]);
1006        ret = utf16s_to_utf8s(report.string, length, UTF16_LITTLE_ENDIAN, buf,
1007                              PAGE_SIZE - 1);
1008        buf[ret++] = '\n';
1009        return ret;
1010}
1011
1012#define CP2112_PSTR_ATTR(name, _report) \
1013static struct cp2112_pstring_attribute dev_attr_##name = { \
1014        .attr = __ATTR(name, (S_IWUSR | S_IRUGO), pstr_show, pstr_store), \
1015        .report = _report, \
1016};
1017
1018CP2112_PSTR_ATTR(manufacturer,  CP2112_MANUFACTURER_STRING);
1019CP2112_PSTR_ATTR(product,       CP2112_PRODUCT_STRING);
1020CP2112_PSTR_ATTR(serial,        CP2112_SERIAL_STRING);
1021
1022#undef CP2112_PSTR_ATTR
1023
1024static const struct attribute_group cp2112_attr_group = {
1025        .attrs = (struct attribute *[]){
1026                &dev_attr_vendor_id.attr,
1027                &dev_attr_product_id.attr,
1028                &dev_attr_max_power.attr,
1029                &dev_attr_power_mode.attr,
1030                &dev_attr_release_version.attr,
1031                &dev_attr_manufacturer.attr.attr,
1032                &dev_attr_product.attr.attr,
1033                &dev_attr_serial.attr.attr,
1034                NULL
1035        }
1036};
1037
1038/* Chmoding our sysfs attributes is simply a way to expose which fields in the
1039 * PROM have already been programmed. We do not depend on this preventing
1040 * writing to these attributes since the CP2112 will simply ignore writes to
1041 * already-programmed fields. This is why there is no sense in fixing this
1042 * racy behaviour.
1043 */
1044static void chmod_sysfs_attrs(struct hid_device *hdev)
1045{
1046        struct attribute **attr;
1047        u8 buf[2];
1048        int ret;
1049
1050        ret = cp2112_hid_get(hdev, CP2112_LOCK_BYTE, buf, sizeof(buf),
1051                             HID_FEATURE_REPORT);
1052        if (ret != sizeof(buf)) {
1053                hid_err(hdev, "error reading lock byte: %d\n", ret);
1054                return;
1055        }
1056
1057        for (attr = cp2112_attr_group.attrs; *attr; ++attr) {
1058                umode_t mode = (buf[1] & 1) ? S_IWUSR | S_IRUGO : S_IRUGO;
1059                ret = sysfs_chmod_file(&hdev->dev.kobj, *attr, mode);
1060                if (ret < 0)
1061                        hid_err(hdev, "error chmoding sysfs file %s\n",
1062                                (*attr)->name);
1063                buf[1] >>= 1;
1064        }
1065}
1066
1067static void cp2112_gpio_irq_ack(struct irq_data *d)
1068{
1069}
1070
1071static void cp2112_gpio_irq_mask(struct irq_data *d)
1072{
1073        struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1074        struct cp2112_device *dev = gpiochip_get_data(gc);
1075
1076        __clear_bit(d->hwirq, &dev->irq_mask);
1077}
1078
1079static void cp2112_gpio_irq_unmask(struct irq_data *d)
1080{
1081        struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1082        struct cp2112_device *dev = gpiochip_get_data(gc);
1083
1084        __set_bit(d->hwirq, &dev->irq_mask);
1085}
1086
1087static void cp2112_gpio_poll_callback(struct work_struct *work)
1088{
1089        struct cp2112_device *dev = container_of(work, struct cp2112_device,
1090                                                 gpio_poll_worker.work);
1091        struct irq_data *d;
1092        u8 gpio_mask;
1093        u8 virqs = (u8)dev->irq_mask;
1094        u32 irq_type;
1095        int irq, virq, ret;
1096
1097        ret = cp2112_gpio_get_all(&dev->gc);
1098        if (ret == -ENODEV) /* the hardware has been disconnected */
1099                return;
1100        if (ret < 0)
1101                goto exit;
1102
1103        gpio_mask = ret;
1104
1105        while (virqs) {
1106                virq = ffs(virqs) - 1;
1107                virqs &= ~BIT(virq);
1108
1109                if (!dev->gc.to_irq)
1110                        break;
1111
1112                irq = dev->gc.to_irq(&dev->gc, virq);
1113
1114                d = irq_get_irq_data(irq);
1115                if (!d)
1116                        continue;
1117
1118                irq_type = irqd_get_trigger_type(d);
1119
1120                if (gpio_mask & BIT(virq)) {
1121                        /* Level High */
1122
1123                        if (irq_type & IRQ_TYPE_LEVEL_HIGH)
1124                                handle_nested_irq(irq);
1125
1126                        if ((irq_type & IRQ_TYPE_EDGE_RISING) &&
1127                            !(dev->gpio_prev_state & BIT(virq)))
1128                                handle_nested_irq(irq);
1129                } else {
1130                        /* Level Low */
1131
1132                        if (irq_type & IRQ_TYPE_LEVEL_LOW)
1133                                handle_nested_irq(irq);
1134
1135                        if ((irq_type & IRQ_TYPE_EDGE_FALLING) &&
1136                            (dev->gpio_prev_state & BIT(virq)))
1137                                handle_nested_irq(irq);
1138                }
1139        }
1140
1141        dev->gpio_prev_state = gpio_mask;
1142
1143exit:
1144        if (dev->gpio_poll)
1145                schedule_delayed_work(&dev->gpio_poll_worker, 10);
1146}
1147
1148
1149static unsigned int cp2112_gpio_irq_startup(struct irq_data *d)
1150{
1151        struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1152        struct cp2112_device *dev = gpiochip_get_data(gc);
1153
1154        INIT_DELAYED_WORK(&dev->gpio_poll_worker, cp2112_gpio_poll_callback);
1155
1156        if (!dev->gpio_poll) {
1157                dev->gpio_poll = true;
1158                schedule_delayed_work(&dev->gpio_poll_worker, 0);
1159        }
1160
1161        cp2112_gpio_irq_unmask(d);
1162        return 0;
1163}
1164
1165static void cp2112_gpio_irq_shutdown(struct irq_data *d)
1166{
1167        struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
1168        struct cp2112_device *dev = gpiochip_get_data(gc);
1169
1170        cancel_delayed_work_sync(&dev->gpio_poll_worker);
1171}
1172
1173static int cp2112_gpio_irq_type(struct irq_data *d, unsigned int type)
1174{
1175        return 0;
1176}
1177
1178static struct irq_chip cp2112_gpio_irqchip = {
1179        .name = "cp2112-gpio",
1180        .irq_startup = cp2112_gpio_irq_startup,
1181        .irq_shutdown = cp2112_gpio_irq_shutdown,
1182        .irq_ack = cp2112_gpio_irq_ack,
1183        .irq_mask = cp2112_gpio_irq_mask,
1184        .irq_unmask = cp2112_gpio_irq_unmask,
1185        .irq_set_type = cp2112_gpio_irq_type,
1186};
1187
1188static int __maybe_unused cp2112_allocate_irq(struct cp2112_device *dev,
1189                                              int pin)
1190{
1191        int ret;
1192
1193        if (dev->desc[pin])
1194                return -EINVAL;
1195
1196        dev->desc[pin] = gpiochip_request_own_desc(&dev->gc, pin,
1197                                                   "HID/I2C:Event",
1198                                                   GPIO_ACTIVE_HIGH,
1199                                                   GPIOD_IN);
1200        if (IS_ERR(dev->desc[pin])) {
1201                dev_err(dev->gc.parent, "Failed to request GPIO\n");
1202                return PTR_ERR(dev->desc[pin]);
1203        }
1204
1205        ret = cp2112_gpio_direction_input(&dev->gc, pin);
1206        if (ret < 0) {
1207                dev_err(dev->gc.parent, "Failed to set GPIO to input dir\n");
1208                goto err_desc;
1209        }
1210
1211        ret = gpiochip_lock_as_irq(&dev->gc, pin);
1212        if (ret) {
1213                dev_err(dev->gc.parent, "Failed to lock GPIO as interrupt\n");
1214                goto err_desc;
1215        }
1216
1217        ret = gpiod_to_irq(dev->desc[pin]);
1218        if (ret < 0) {
1219                dev_err(dev->gc.parent, "Failed to translate GPIO to IRQ\n");
1220                goto err_lock;
1221        }
1222
1223        return ret;
1224
1225err_lock:
1226        gpiochip_unlock_as_irq(&dev->gc, pin);
1227err_desc:
1228        gpiochip_free_own_desc(dev->desc[pin]);
1229        dev->desc[pin] = NULL;
1230        return ret;
1231}
1232
1233static int cp2112_probe(struct hid_device *hdev, const struct hid_device_id *id)
1234{
1235        struct cp2112_device *dev;
1236        u8 buf[3];
1237        struct cp2112_smbus_config_report config;
1238        int ret;
1239
1240        dev = devm_kzalloc(&hdev->dev, sizeof(*dev), GFP_KERNEL);
1241        if (!dev)
1242                return -ENOMEM;
1243
1244        dev->in_out_buffer = devm_kzalloc(&hdev->dev, CP2112_REPORT_MAX_LENGTH,
1245                                          GFP_KERNEL);
1246        if (!dev->in_out_buffer)
1247                return -ENOMEM;
1248
1249        mutex_init(&dev->lock);
1250
1251        ret = hid_parse(hdev);
1252        if (ret) {
1253                hid_err(hdev, "parse failed\n");
1254                return ret;
1255        }
1256
1257        ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
1258        if (ret) {
1259                hid_err(hdev, "hw start failed\n");
1260                return ret;
1261        }
1262
1263        ret = hid_hw_open(hdev);
1264        if (ret) {
1265                hid_err(hdev, "hw open failed\n");
1266                goto err_hid_stop;
1267        }
1268
1269        ret = hid_hw_power(hdev, PM_HINT_FULLON);
1270        if (ret < 0) {
1271                hid_err(hdev, "power management error: %d\n", ret);
1272                goto err_hid_close;
1273        }
1274
1275        ret = cp2112_hid_get(hdev, CP2112_GET_VERSION_INFO, buf, sizeof(buf),
1276                             HID_FEATURE_REPORT);
1277        if (ret != sizeof(buf)) {
1278                hid_err(hdev, "error requesting version\n");
1279                if (ret >= 0)
1280                        ret = -EIO;
1281                goto err_power_normal;
1282        }
1283
1284        hid_info(hdev, "Part Number: 0x%02X Device Version: 0x%02X\n",
1285                 buf[1], buf[2]);
1286
1287        ret = cp2112_hid_get(hdev, CP2112_SMBUS_CONFIG, (u8 *)&config,
1288                             sizeof(config), HID_FEATURE_REPORT);
1289        if (ret != sizeof(config)) {
1290                hid_err(hdev, "error requesting SMBus config\n");
1291                if (ret >= 0)
1292                        ret = -EIO;
1293                goto err_power_normal;
1294        }
1295
1296        config.retry_time = cpu_to_be16(1);
1297
1298        ret = cp2112_hid_output(hdev, (u8 *)&config, sizeof(config),
1299                                HID_FEATURE_REPORT);
1300        if (ret != sizeof(config)) {
1301                hid_err(hdev, "error setting SMBus config\n");
1302                if (ret >= 0)
1303                        ret = -EIO;
1304                goto err_power_normal;
1305        }
1306
1307        hid_set_drvdata(hdev, (void *)dev);
1308        dev->hdev               = hdev;
1309        dev->adap.owner         = THIS_MODULE;
1310        dev->adap.class         = I2C_CLASS_HWMON;
1311        dev->adap.algo          = &smbus_algorithm;
1312        dev->adap.algo_data     = dev;
1313        dev->adap.dev.parent    = &hdev->dev;
1314        snprintf(dev->adap.name, sizeof(dev->adap.name),
1315                 "CP2112 SMBus Bridge on hidraw%d",
1316                 ((struct hidraw *)hdev->hidraw)->minor);
1317        dev->hwversion = buf[2];
1318        init_waitqueue_head(&dev->wait);
1319
1320        hid_device_io_start(hdev);
1321        ret = i2c_add_adapter(&dev->adap);
1322        hid_device_io_stop(hdev);
1323
1324        if (ret) {
1325                hid_err(hdev, "error registering i2c adapter\n");
1326                goto err_power_normal;
1327        }
1328
1329        hid_dbg(hdev, "adapter registered\n");
1330
1331        dev->gc.label                   = "cp2112_gpio";
1332        dev->gc.direction_input         = cp2112_gpio_direction_input;
1333        dev->gc.direction_output        = cp2112_gpio_direction_output;
1334        dev->gc.set                     = cp2112_gpio_set;
1335        dev->gc.get                     = cp2112_gpio_get;
1336        dev->gc.base                    = -1;
1337        dev->gc.ngpio                   = 8;
1338        dev->gc.can_sleep               = 1;
1339        dev->gc.parent                  = &hdev->dev;
1340
1341        ret = gpiochip_add_data(&dev->gc, dev);
1342        if (ret < 0) {
1343                hid_err(hdev, "error registering gpio chip\n");
1344                goto err_free_i2c;
1345        }
1346
1347        ret = sysfs_create_group(&hdev->dev.kobj, &cp2112_attr_group);
1348        if (ret < 0) {
1349                hid_err(hdev, "error creating sysfs attrs\n");
1350                goto err_gpiochip_remove;
1351        }
1352
1353        chmod_sysfs_attrs(hdev);
1354        hid_hw_power(hdev, PM_HINT_NORMAL);
1355
1356        ret = gpiochip_irqchip_add(&dev->gc, &cp2112_gpio_irqchip, 0,
1357                                   handle_simple_irq, IRQ_TYPE_NONE);
1358        if (ret) {
1359                dev_err(dev->gc.parent, "failed to add IRQ chip\n");
1360                goto err_sysfs_remove;
1361        }
1362
1363        return ret;
1364
1365err_sysfs_remove:
1366        sysfs_remove_group(&hdev->dev.kobj, &cp2112_attr_group);
1367err_gpiochip_remove:
1368        gpiochip_remove(&dev->gc);
1369err_free_i2c:
1370        i2c_del_adapter(&dev->adap);
1371err_power_normal:
1372        hid_hw_power(hdev, PM_HINT_NORMAL);
1373err_hid_close:
1374        hid_hw_close(hdev);
1375err_hid_stop:
1376        hid_hw_stop(hdev);
1377        return ret;
1378}
1379
1380static void cp2112_remove(struct hid_device *hdev)
1381{
1382        struct cp2112_device *dev = hid_get_drvdata(hdev);
1383        int i;
1384
1385        sysfs_remove_group(&hdev->dev.kobj, &cp2112_attr_group);
1386        i2c_del_adapter(&dev->adap);
1387
1388        if (dev->gpio_poll) {
1389                dev->gpio_poll = false;
1390                cancel_delayed_work_sync(&dev->gpio_poll_worker);
1391        }
1392
1393        for (i = 0; i < ARRAY_SIZE(dev->desc); i++) {
1394                gpiochip_unlock_as_irq(&dev->gc, i);
1395                gpiochip_free_own_desc(dev->desc[i]);
1396        }
1397
1398        gpiochip_remove(&dev->gc);
1399        /* i2c_del_adapter has finished removing all i2c devices from our
1400         * adapter. Well behaved devices should no longer call our cp2112_xfer
1401         * and should have waited for any pending calls to finish. It has also
1402         * waited for device_unregister(&adap->dev) to complete. Therefore we
1403         * can safely free our struct cp2112_device.
1404         */
1405        hid_hw_close(hdev);
1406        hid_hw_stop(hdev);
1407}
1408
1409static int cp2112_raw_event(struct hid_device *hdev, struct hid_report *report,
1410                            u8 *data, int size)
1411{
1412        struct cp2112_device *dev = hid_get_drvdata(hdev);
1413        struct cp2112_xfer_status_report *xfer = (void *)data;
1414
1415        switch (data[0]) {
1416        case CP2112_TRANSFER_STATUS_RESPONSE:
1417                hid_dbg(hdev, "xfer status: %02x %02x %04x %04x\n",
1418                        xfer->status0, xfer->status1,
1419                        be16_to_cpu(xfer->retries), be16_to_cpu(xfer->length));
1420
1421                switch (xfer->status0) {
1422                case STATUS0_IDLE:
1423                        dev->xfer_status = -EAGAIN;
1424                        break;
1425                case STATUS0_BUSY:
1426                        dev->xfer_status = -EBUSY;
1427                        break;
1428                case STATUS0_COMPLETE:
1429                        dev->xfer_status = be16_to_cpu(xfer->length);
1430                        break;
1431                case STATUS0_ERROR:
1432                        switch (xfer->status1) {
1433                        case STATUS1_TIMEOUT_NACK:
1434                        case STATUS1_TIMEOUT_BUS:
1435                                dev->xfer_status = -ETIMEDOUT;
1436                                break;
1437                        default:
1438                                dev->xfer_status = -EIO;
1439                                break;
1440                        }
1441                        break;
1442                default:
1443                        dev->xfer_status = -EINVAL;
1444                        break;
1445                }
1446
1447                atomic_set(&dev->xfer_avail, 1);
1448                break;
1449        case CP2112_DATA_READ_RESPONSE:
1450                hid_dbg(hdev, "read response: %02x %02x\n", data[1], data[2]);
1451
1452                dev->read_length = data[2];
1453                if (dev->read_length > sizeof(dev->read_data))
1454                        dev->read_length = sizeof(dev->read_data);
1455
1456                memcpy(dev->read_data, &data[3], dev->read_length);
1457                atomic_set(&dev->read_avail, 1);
1458                break;
1459        default:
1460                hid_err(hdev, "unknown report\n");
1461
1462                return 0;
1463        }
1464
1465        wake_up_interruptible(&dev->wait);
1466        return 1;
1467}
1468
1469static struct hid_driver cp2112_driver = {
1470        .name           = "cp2112",
1471        .id_table       = cp2112_devices,
1472        .probe          = cp2112_probe,
1473        .remove         = cp2112_remove,
1474        .raw_event      = cp2112_raw_event,
1475};
1476
1477module_hid_driver(cp2112_driver);
1478MODULE_DESCRIPTION("Silicon Labs HID USB to SMBus master bridge");
1479MODULE_AUTHOR("David Barksdale <dbarksdale@uplogix.com>");
1480MODULE_LICENSE("GPL");
1481
1482