drivers/hid/i2c-hid/i2c-hid-core.c

   1 /*
   2  * HID over I2C protocol implementation
   3  *
   4  * Copyright (c) 2012 Benjamin Tissoires <benjamin.tissoires@gmail.com>
   5  * Copyright (c) 2012 Ecole Nationale de l'Aviation Civile, France
   6  * Copyright (c) 2012 Red Hat, Inc
   7  *
   8  * This code is partly based on "USB HID support for Linux":
   9  *
  10  *  Copyright (c) 1999 Andreas Gal
  11  *  Copyright (c) 2000-2005 Vojtech Pavlik <vojtech@suse.cz>
  12  *  Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc
  13  *  Copyright (c) 2007-2008 Oliver Neukum
  14  *  Copyright (c) 2006-2010 Jiri Kosina
  15  *
  16  * This file is subject to the terms and conditions of the GNU General Public
  17  * License.  See the file COPYING in the main directory of this archive for
  18  * more details.
  19  */
  20
  21 #include <linux/module.h>
  22 #include <linux/i2c.h>
  23 #include <linux/interrupt.h>
  24 #include <linux/input.h>
  25 #include <linux/delay.h>
  26 #include <linux/slab.h>
  27 #include <linux/pm.h>
  28 #include <linux/pm_runtime.h>
  29 #include <linux/device.h>
  30 #include <linux/wait.h>
  31 #include <linux/err.h>
  32 #include <linux/string.h>
  33 #include <linux/list.h>
  34 #include <linux/jiffies.h>
  35 #include <linux/kernel.h>
  36 #include <linux/hid.h>
  37 #include <linux/mutex.h>
  38 #include <linux/acpi.h>
  39 #include <linux/of.h>
  40 #include <linux/gpio/consumer.h>
  41
  42 #include <linux/i2c/i2c-hid.h>
  43
  44 #include "../hid-ids.h"
  45 #include "i2c-hid.h"
  46
  47 /* quirks to control the device */
  48 #define I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV        BIT(0)
  49
  50 /* flags */
  51 #define I2C_HID_STARTED         0
  52 #define I2C_HID_RESET_PENDING   1
  53 #define I2C_HID_READ_PENDING    2
  54
  55 #define I2C_HID_PWR_ON          0x00
  56 #define I2C_HID_PWR_SLEEP       0x01
  57
  58 /* debug option */
  59 static bool debug;
  60 module_param(debug, bool, 0444);
  61 MODULE_PARM_DESC(debug, "print a lot of debug information");
  62
  63 #define i2c_hid_dbg(ihid, fmt, arg...)                                    \
  64 do {                                                                      \
  65         if (debug)                                                        \
  66                 dev_printk(KERN_DEBUG, &(ihid)->client->dev, fmt, ##arg); \
  67 } while (0)
  68
  69 struct i2c_hid_desc {
  70         __le16 wHIDDescLength;
  71         __le16 bcdVersion;
  72         __le16 wReportDescLength;
  73         __le16 wReportDescRegister;
  74         __le16 wInputRegister;
  75         __le16 wMaxInputLength;
  76         __le16 wOutputRegister;
  77         __le16 wMaxOutputLength;
  78         __le16 wCommandRegister;
  79         __le16 wDataRegister;
  80         __le16 wVendorID;
  81         __le16 wProductID;
  82         __le16 wVersionID;
  83         __le32 reserved;
  84 } __packed;
  85
  86 struct i2c_hid_cmd {
  87         unsigned int registerIndex;
  88         __u8 opcode;
  89         unsigned int length;
  90         bool wait;
  91 };
  92
  93 union command {
  94         u8 data[0];
  95         struct cmd {
  96                 __le16 reg;
  97                 __u8 reportTypeID;
  98                 __u8 opcode;
  99         } __packed c;
 100 };
 101
 102 #define I2C_HID_CMD(opcode_) \
 103         .opcode = opcode_, .length = 4, \
 104         .registerIndex = offsetof(struct i2c_hid_desc, wCommandRegister)
 105
 106 /* fetch HID descriptor */
 107 static const struct i2c_hid_cmd hid_descr_cmd = { .length = 2 };
 108 /* fetch report descriptors */
 109 static const struct i2c_hid_cmd hid_report_descr_cmd = {
 110                 .registerIndex = offsetof(struct i2c_hid_desc,
 111                         wReportDescRegister),
 112                 .opcode = 0x00,
 113                 .length = 2 };
 114 /* commands */
 115 static const struct i2c_hid_cmd hid_reset_cmd =         { I2C_HID_CMD(0x01),
 116                                                           .wait = true };
 117 static const struct i2c_hid_cmd hid_get_report_cmd =    { I2C_HID_CMD(0x02) };
 118 static const struct i2c_hid_cmd hid_set_report_cmd =    { I2C_HID_CMD(0x03) };
 119 static const struct i2c_hid_cmd hid_set_power_cmd =     { I2C_HID_CMD(0x08) };
 120 static const struct i2c_hid_cmd hid_no_cmd =            { .length = 0 };
 121
 122 /*
 123  * These definitions are not used here, but are defined by the spec.
 124  * Keeping them here for documentation purposes.
 125  *
 126  * static const struct i2c_hid_cmd hid_get_idle_cmd = { I2C_HID_CMD(0x04) };
 127  * static const struct i2c_hid_cmd hid_set_idle_cmd = { I2C_HID_CMD(0x05) };
 128  * static const struct i2c_hid_cmd hid_get_protocol_cmd = { I2C_HID_CMD(0x06) };
 129  * static const struct i2c_hid_cmd hid_set_protocol_cmd = { I2C_HID_CMD(0x07) };
 130  */
 131
 132 static DEFINE_MUTEX(i2c_hid_open_mut);
 133
 134 /* The main device structure */
 135 struct i2c_hid {
 136         struct i2c_client       *client;        /* i2c client */
 137         struct hid_device       *hid;   /* pointer to corresponding HID dev */
 138         union {
 139                 __u8 hdesc_buffer[sizeof(struct i2c_hid_desc)];
 140                 struct i2c_hid_desc hdesc;      /* the HID Descriptor */
 141         };
 142         __le16                  wHIDDescRegister; /* location of the i2c
 143                                                    * register of the HID
 144                                                    * descriptor. */
 145         unsigned int            bufsize;        /* i2c buffer size */
 146         u8                      *inbuf;         /* Input buffer */
 147         u8                      *rawbuf;        /* Raw Input buffer */
 148         u8                      *cmdbuf;        /* Command buffer */
 149         u8                      *argsbuf;       /* Command arguments buffer */
 150
 151         unsigned long           flags;          /* device flags */
 152         unsigned long           quirks;         /* Various quirks */
 153
 154         wait_queue_head_t       wait;           /* For waiting the interrupt */
 155         struct gpio_desc        *desc;
 156         int                     irq;
 157
 158         struct i2c_hid_platform_data pdata;
 159
 160         bool                    irq_wake_enabled;
 161         struct mutex            reset_lock;
 162 };
 163
 164 static const struct i2c_hid_quirks {
 165         __u16 idVendor;
 166         __u16 idProduct;
 167         __u32 quirks;
 168 } i2c_hid_quirks[] = {
 169         { USB_VENDOR_ID_WEIDA, USB_DEVICE_ID_WEIDA_8752,
 170                 I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV },
 171         { USB_VENDOR_ID_WEIDA, USB_DEVICE_ID_WEIDA_8755,
 172                 I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV },
 173         { 0, 0 }
 174 };
 175
 176 /*
 177  * i2c_hid_lookup_quirk: return any quirks associated with a I2C HID device
 178  * @idVendor: the 16-bit vendor ID
 179  * @idProduct: the 16-bit product ID
 180  *
 181  * Returns: a u32 quirks value.
 182  */
 183 static u32 i2c_hid_lookup_quirk(const u16 idVendor, const u16 idProduct)
 184 {
 185         u32 quirks = 0;
 186         int n;
 187
 188         for (n = 0; i2c_hid_quirks[n].idVendor; n++)
 189                 if (i2c_hid_quirks[n].idVendor == idVendor &&
 190                     (i2c_hid_quirks[n].idProduct == (__u16)HID_ANY_ID ||
 191                      i2c_hid_quirks[n].idProduct == idProduct))
 192                         quirks = i2c_hid_quirks[n].quirks;
 193
 194         return quirks;
 195 }
 196
 197 static int __i2c_hid_command(struct i2c_client *client,
 198                 const struct i2c_hid_cmd *command, u8 reportID,
 199                 u8 reportType, u8 *args, int args_len,
 200                 unsigned char *buf_recv, int data_len)
 201 {
 202         struct i2c_hid *ihid = i2c_get_clientdata(client);
 203         union command *cmd = (union command *)ihid->cmdbuf;
 204         int ret;
 205         struct i2c_msg msg[2];
 206         int msg_num = 1;
 207
 208         int length = command->length;
 209         bool wait = command->wait;
 210         unsigned int registerIndex = command->registerIndex;
 211
 212         /* special case for hid_descr_cmd */
 213         if (command == &hid_descr_cmd) {
 214                 cmd->c.reg = ihid->wHIDDescRegister;
 215         } else {
 216                 cmd->data[0] = ihid->hdesc_buffer[registerIndex];
 217                 cmd->data[1] = ihid->hdesc_buffer[registerIndex + 1];
 218         }
 219
 220         if (length > 2) {
 221                 cmd->c.opcode = command->opcode;
 222                 cmd->c.reportTypeID = reportID | reportType << 4;
 223         }
 224
 225         memcpy(cmd->data + length, args, args_len);
 226         length += args_len;
 227
 228         i2c_hid_dbg(ihid, "%s: cmd=%*ph\n", __func__, length, cmd->data);
 229
 230         msg[0].addr = client->addr;
 231         msg[0].flags = client->flags & I2C_M_TEN;
 232         msg[0].len = length;
 233         msg[0].buf = cmd->data;
 234         if (data_len > 0) {
 235                 msg[1].addr = client->addr;
 236                 msg[1].flags = client->flags & I2C_M_TEN;
 237                 msg[1].flags |= I2C_M_RD;
 238                 msg[1].len = data_len;
 239                 msg[1].buf = buf_recv;
 240                 msg_num = 2;
 241                 set_bit(I2C_HID_READ_PENDING, &ihid->flags);
 242         }
 243
 244         if (wait)
 245                 set_bit(I2C_HID_RESET_PENDING, &ihid->flags);
 246
 247         ret = i2c_transfer(client->adapter, msg, msg_num);
 248
 249         if (data_len > 0)
 250                 clear_bit(I2C_HID_READ_PENDING, &ihid->flags);
 251
 252         if (ret != msg_num)
 253                 return ret < 0 ? ret : -EIO;
 254
 255         ret = 0;
 256
 257         if (wait) {
 258                 i2c_hid_dbg(ihid, "%s: waiting...\n", __func__);
 259                 if (!wait_event_timeout(ihid->wait,
 260                                 !test_bit(I2C_HID_RESET_PENDING, &ihid->flags),
 261                                 msecs_to_jiffies(5000)))
 262                         ret = -ENODATA;
 263                 i2c_hid_dbg(ihid, "%s: finished.\n", __func__);
 264         }
 265
 266         return ret;
 267 }
 268
 269 static int i2c_hid_command(struct i2c_client *client,
 270                 const struct i2c_hid_cmd *command,
 271                 unsigned char *buf_recv, int data_len)
 272 {
 273         return __i2c_hid_command(client, command, 0, 0, NULL, 0,
 274                                 buf_recv, data_len);
 275 }
 276
 277 static int i2c_hid_get_report(struct i2c_client *client, u8 reportType,
 278                 u8 reportID, unsigned char *buf_recv, int data_len)
 279 {
 280         struct i2c_hid *ihid = i2c_get_clientdata(client);
 281         u8 args[3];
 282         int ret;
 283         int args_len = 0;
 284         u16 readRegister = le16_to_cpu(ihid->hdesc.wDataRegister);
 285
 286         i2c_hid_dbg(ihid, "%s\n", __func__);
 287
 288         if (reportID >= 0x0F) {
 289                 args[args_len++] = reportID;
 290                 reportID = 0x0F;
 291         }
 292
 293         args[args_len++] = readRegister & 0xFF;
 294         args[args_len++] = readRegister >> 8;
 295
 296         ret = __i2c_hid_command(client, &hid_get_report_cmd, reportID,
 297                 reportType, args, args_len, buf_recv, data_len);
 298         if (ret) {
 299                 dev_err(&client->dev,
 300                         "failed to retrieve report from device.\n");
 301                 return ret;
 302         }
 303
 304         return 0;
 305 }
 306
 307 /**
 308  * i2c_hid_set_or_send_report: forward an incoming report to the device
 309  * @client: the i2c_client of the device
 310  * @reportType: 0x03 for HID_FEATURE_REPORT ; 0x02 for HID_OUTPUT_REPORT
 311  * @reportID: the report ID
 312  * @buf: the actual data to transfer, without the report ID
 313  * @len: size of buf
 314  * @use_data: true: use SET_REPORT HID command, false: send plain OUTPUT report
 315  */
 316 static int i2c_hid_set_or_send_report(struct i2c_client *client, u8 reportType,
 317                 u8 reportID, unsigned char *buf, size_t data_len, bool use_data)
 318 {
 319         struct i2c_hid *ihid = i2c_get_clientdata(client);
 320         u8 *args = ihid->argsbuf;
 321         const struct i2c_hid_cmd *hidcmd;
 322         int ret;
 323         u16 dataRegister = le16_to_cpu(ihid->hdesc.wDataRegister);
 324         u16 outputRegister = le16_to_cpu(ihid->hdesc.wOutputRegister);
 325         u16 maxOutputLength = le16_to_cpu(ihid->hdesc.wMaxOutputLength);
 326         u16 size;
 327         int args_len;
 328         int index = 0;
 329
 330         i2c_hid_dbg(ihid, "%s\n", __func__);
 331
 332         if (data_len > ihid->bufsize)
 333                 return -EINVAL;
 334
 335         size =          2                       /* size */ +
 336                         (reportID ? 1 : 0)      /* reportID */ +
 337                         data_len                /* buf */;
 338         args_len =      (reportID >= 0x0F ? 1 : 0) /* optional third byte */ +
 339                         2                       /* dataRegister */ +
 340                         size                    /* args */;
 341
 342         if (!use_data && maxOutputLength == 0)
 343                 return -ENOSYS;
 344
 345         if (reportID >= 0x0F) {
 346                 args[index++] = reportID;
 347                 reportID = 0x0F;
 348         }
 349
 350         /*
 351          * use the data register for feature reports or if the device does not
 352          * support the output register
 353          */
 354         if (use_data) {
 355                 args[index++] = dataRegister & 0xFF;
 356                 args[index++] = dataRegister >> 8;
 357                 hidcmd = &hid_set_report_cmd;
 358         } else {
 359                 args[index++] = outputRegister & 0xFF;
 360                 args[index++] = outputRegister >> 8;
 361                 hidcmd = &hid_no_cmd;
 362         }
 363
 364         args[index++] = size & 0xFF;
 365         args[index++] = size >> 8;
 366
 367         if (reportID)
 368                 args[index++] = reportID;
 369
 370         memcpy(&args[index], buf, data_len);
 371
 372         ret = __i2c_hid_command(client, hidcmd, reportID,
 373                 reportType, args, args_len, NULL, 0);
 374         if (ret) {
 375                 dev_err(&client->dev, "failed to set a report to device.\n");
 376                 return ret;
 377         }
 378
 379         return data_len;
 380 }
 381
 382 static int i2c_hid_set_power(struct i2c_client *client, int power_state)
 383 {
 384         struct i2c_hid *ihid = i2c_get_clientdata(client);
 385         int ret;
 386
 387         i2c_hid_dbg(ihid, "%s\n", __func__);
 388
 389         /*
 390          * Some devices require to send a command to wakeup before power on.
 391          * The call will get a return value (EREMOTEIO) but device will be
 392          * triggered and activated. After that, it goes like a normal device.
 393          */
 394         if (power_state == I2C_HID_PWR_ON &&
 395             ihid->quirks & I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV) {
 396                 ret = i2c_hid_command(client, &hid_set_power_cmd, NULL, 0);
 397
 398                 /* Device was already activated */
 399                 if (!ret)
 400                         goto set_pwr_exit;
 401         }
 402
 403         ret = __i2c_hid_command(client, &hid_set_power_cmd, power_state,
 404                 0, NULL, 0, NULL, 0);
 405
 406         if (ret)
 407                 dev_err(&client->dev, "failed to change power setting.\n");
 408
 409 set_pwr_exit:
 410
 411         /*
 412          * The HID over I2C specification states that if a DEVICE needs time
 413          * after the PWR_ON request, it should utilise CLOCK stretching.
 414          * However, it has been observered that the Windows driver provides a
 415          * 1ms sleep between the PWR_ON and RESET requests.
 416          * According to Goodix Windows even waits 60 ms after (other?)
 417          * PWR_ON requests. Testing has confirmed that several devices
 418          * will not work properly without a delay after a PWR_ON request.
 419          */
 420         if (!ret && power_state == I2C_HID_PWR_ON)
 421                 msleep(60);
 422
 423         return ret;
 424 }
 425
 426 static int i2c_hid_hwreset(struct i2c_client *client)
 427 {
 428         struct i2c_hid *ihid = i2c_get_clientdata(client);
 429         int ret;
 430
 431         i2c_hid_dbg(ihid, "%s\n", __func__);
 432
 433         /*
 434          * This prevents sending feature reports while the device is
 435          * being reset. Otherwise we may lose the reset complete
 436          * interrupt.
 437          */
 438         mutex_lock(&ihid->reset_lock);
 439
 440         ret = i2c_hid_set_power(client, I2C_HID_PWR_ON);
 441         if (ret)
 442                 goto out_unlock;
 443
 444         i2c_hid_dbg(ihid, "resetting...\n");
 445
 446         ret = i2c_hid_command(client, &hid_reset_cmd, NULL, 0);
 447         if (ret) {
 448                 dev_err(&client->dev, "failed to reset device.\n");
 449                 i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
 450         }
 451
 452 out_unlock:
 453         mutex_unlock(&ihid->reset_lock);
 454         return ret;
 455 }
 456
 457 static void i2c_hid_get_input(struct i2c_hid *ihid)
 458 {
 459         int ret;
 460         u32 ret_size;
 461         int size = le16_to_cpu(ihid->hdesc.wMaxInputLength);
 462
 463         if (size > ihid->bufsize)
 464                 size = ihid->bufsize;
 465
 466         ret = i2c_master_recv(ihid->client, ihid->inbuf, size);
 467         if (ret != size) {
 468                 if (ret < 0)
 469                         return;
 470
 471                 dev_err(&ihid->client->dev, "%s: got %d data instead of %d\n",
 472                         __func__, ret, size);
 473                 return;
 474         }
 475
 476         ret_size = ihid->inbuf[0] | ihid->inbuf[1] << 8;
 477
 478         if (!ret_size) {
 479                 /* host or device initiated RESET completed */
 480                 if (test_and_clear_bit(I2C_HID_RESET_PENDING, &ihid->flags))
 481                         wake_up(&ihid->wait);
 482                 return;
 483         }
 484
 485         if ((ret_size > size) || (ret_size < 2)) {
 486                 dev_err(&ihid->client->dev, "%s: incomplete report (%d/%d)\n",
 487                         __func__, size, ret_size);
 488                 return;
 489         }
 490
 491         i2c_hid_dbg(ihid, "input: %*ph\n", ret_size, ihid->inbuf);
 492
 493         if (test_bit(I2C_HID_STARTED, &ihid->flags))
 494                 hid_input_report(ihid->hid, HID_INPUT_REPORT, ihid->inbuf + 2,
 495                                 ret_size - 2, 1);
 496
 497         return;
 498 }
 499
 500 static irqreturn_t i2c_hid_irq(int irq, void *dev_id)
 501 {
 502         struct i2c_hid *ihid = dev_id;
 503
 504         if (test_bit(I2C_HID_READ_PENDING, &ihid->flags))
 505                 return IRQ_HANDLED;
 506
 507         i2c_hid_get_input(ihid);
 508
 509         return IRQ_HANDLED;
 510 }
 511
 512 static int i2c_hid_get_report_length(struct hid_report *report)
 513 {
 514         return ((report->size - 1) >> 3) + 1 +
 515                 report->device->report_enum[report->type].numbered + 2;
 516 }
 517
 518 static void i2c_hid_init_report(struct hid_report *report, u8 *buffer,
 519         size_t bufsize)
 520 {
 521         struct hid_device *hid = report->device;
 522         struct i2c_client *client = hid->driver_data;
 523         struct i2c_hid *ihid = i2c_get_clientdata(client);
 524         unsigned int size, ret_size;
 525
 526         size = i2c_hid_get_report_length(report);
 527         if (i2c_hid_get_report(client,
 528                         report->type == HID_FEATURE_REPORT ? 0x03 : 0x01,
 529                         report->id, buffer, size))
 530                 return;
 531
 532         i2c_hid_dbg(ihid, "report (len=%d): %*ph\n", size, size, buffer);
 533
 534         ret_size = buffer[0] | (buffer[1] << 8);
 535
 536         if (ret_size != size) {
 537                 dev_err(&client->dev, "error in %s size:%d / ret_size:%d\n",
 538                         __func__, size, ret_size);
 539                 return;
 540         }
 541
 542         /* hid->driver_lock is held as we are in probe function,
 543          * we just need to setup the input fields, so using
 544          * hid_report_raw_event is safe. */
 545         hid_report_raw_event(hid, report->type, buffer + 2, size - 2, 1);
 546 }
 547
 548 /*
 549  * Initialize all reports
 550  */
 551 static void i2c_hid_init_reports(struct hid_device *hid)
 552 {
 553         struct hid_report *report;
 554         struct i2c_client *client = hid->driver_data;
 555         struct i2c_hid *ihid = i2c_get_clientdata(client);
 556         u8 *inbuf = kzalloc(ihid->bufsize, GFP_KERNEL);
 557
 558         if (!inbuf) {
 559                 dev_err(&client->dev, "can not retrieve initial reports\n");
 560                 return;
 561         }
 562
 563         /*
 564          * The device must be powered on while we fetch initial reports
 565          * from it.
 566          */
 567         pm_runtime_get_sync(&client->dev);
 568
 569         list_for_each_entry(report,
 570                 &hid->report_enum[HID_FEATURE_REPORT].report_list, list)
 571                 i2c_hid_init_report(report, inbuf, ihid->bufsize);
 572
 573         pm_runtime_put(&client->dev);
 574
 575         kfree(inbuf);
 576 }
 577
 578 /*
 579  * Traverse the supplied list of reports and find the longest
 580  */
 581 static void i2c_hid_find_max_report(struct hid_device *hid, unsigned int type,
 582                 unsigned int *max)
 583 {
 584         struct hid_report *report;
 585         unsigned int size;
 586
 587         /* We should not rely on wMaxInputLength, as some devices may set it to
 588          * a wrong length. */
 589         list_for_each_entry(report, &hid->report_enum[type].report_list, list) {
 590                 size = i2c_hid_get_report_length(report);
 591                 if (*max < size)
 592                         *max = size;
 593         }
 594 }
 595
 596 static void i2c_hid_free_buffers(struct i2c_hid *ihid)
 597 {
 598         kfree(ihid->inbuf);
 599         kfree(ihid->rawbuf);
 600         kfree(ihid->argsbuf);
 601         kfree(ihid->cmdbuf);
 602         ihid->inbuf = NULL;
 603         ihid->rawbuf = NULL;
 604         ihid->cmdbuf = NULL;
 605         ihid->argsbuf = NULL;
 606         ihid->bufsize = 0;
 607 }
 608
 609 static int i2c_hid_alloc_buffers(struct i2c_hid *ihid, size_t report_size)
 610 {
 611         /* the worst case is computed from the set_report command with a
 612          * reportID > 15 and the maximum report length */
 613         int args_len = sizeof(__u8) + /* ReportID */
 614                        sizeof(__u8) + /* optional ReportID byte */
 615                        sizeof(__u16) + /* data register */
 616                        sizeof(__u16) + /* size of the report */
 617                        report_size; /* report */
 618
 619         ihid->inbuf = kzalloc(report_size, GFP_KERNEL);
 620         ihid->rawbuf = kzalloc(report_size, GFP_KERNEL);
 621         ihid->argsbuf = kzalloc(args_len, GFP_KERNEL);
 622         ihid->cmdbuf = kzalloc(sizeof(union command) + args_len, GFP_KERNEL);
 623
 624         if (!ihid->inbuf || !ihid->rawbuf || !ihid->argsbuf || !ihid->cmdbuf) {
 625                 i2c_hid_free_buffers(ihid);
 626                 return -ENOMEM;
 627         }
 628
 629         ihid->bufsize = report_size;
 630
 631         return 0;
 632 }
 633
 634 static int i2c_hid_get_raw_report(struct hid_device *hid,
 635                 unsigned char report_number, __u8 *buf, size_t count,
 636                 unsigned char report_type)
 637 {
 638         struct i2c_client *client = hid->driver_data;
 639         struct i2c_hid *ihid = i2c_get_clientdata(client);
 640         size_t ret_count, ask_count;
 641         int ret;
 642
 643         if (report_type == HID_OUTPUT_REPORT)
 644                 return -EINVAL;
 645
 646         /*
 647          * In case of unnumbered reports the response from the device will
 648          * not have the report ID that the upper layers expect, so we need
 649          * to stash it the buffer ourselves and adjust the data size.
 650          */
 651         if (!report_number) {
 652                 buf[0] = 0;
 653                 buf++;
 654                 count--;
 655         }
 656
 657         /* +2 bytes to include the size of the reply in the query buffer */
 658         ask_count = min(count + 2, (size_t)ihid->bufsize);
 659
 660         ret = i2c_hid_get_report(client,
 661                         report_type == HID_FEATURE_REPORT ? 0x03 : 0x01,
 662                         report_number, ihid->rawbuf, ask_count);
 663
 664         if (ret < 0)
 665                 return ret;
 666
 667         ret_count = ihid->rawbuf[0] | (ihid->rawbuf[1] << 8);
 668
 669         if (ret_count <= 2)
 670                 return 0;
 671
 672         ret_count = min(ret_count, ask_count);
 673
 674         /* The query buffer contains the size, dropping it in the reply */
 675         count = min(count, ret_count - 2);
 676         memcpy(buf, ihid->rawbuf + 2, count);
 677
 678         if (!report_number)
 679                 count++;
 680
 681         return count;
 682 }
 683
 684 static int i2c_hid_output_raw_report(struct hid_device *hid, __u8 *buf,
 685                 size_t count, unsigned char report_type, bool use_data)
 686 {
 687         struct i2c_client *client = hid->driver_data;
 688         struct i2c_hid *ihid = i2c_get_clientdata(client);
 689         int report_id = buf[0];
 690         int ret;
 691
 692         if (report_type == HID_INPUT_REPORT)
 693                 return -EINVAL;
 694
 695         mutex_lock(&ihid->reset_lock);
 696
 697         /*
 698          * Note that both numbered and unnumbered reports passed here
 699          * are supposed to have report ID stored in the 1st byte of the
 700          * buffer, so we strip it off unconditionally before passing payload
 701          * to i2c_hid_set_or_send_report which takes care of encoding
 702          * everything properly.
 703          */
 704         ret = i2c_hid_set_or_send_report(client,
 705                                 report_type == HID_FEATURE_REPORT ? 0x03 : 0x02,
 706                                 report_id, buf + 1, count - 1, use_data);
 707
 708         if (ret >= 0)
 709                 ret++; /* add report_id to the number of transferred bytes */
 710
 711         mutex_unlock(&ihid->reset_lock);
 712
 713         return ret;
 714 }
 715
 716 static int i2c_hid_output_report(struct hid_device *hid, __u8 *buf,
 717                 size_t count)
 718 {
 719         return i2c_hid_output_raw_report(hid, buf, count, HID_OUTPUT_REPORT,
 720                         false);
 721 }
 722
 723 static int i2c_hid_raw_request(struct hid_device *hid, unsigned char reportnum,
 724                                __u8 *buf, size_t len, unsigned char rtype,
 725                                int reqtype)
 726 {
 727         switch (reqtype) {
 728         case HID_REQ_GET_REPORT:
 729                 return i2c_hid_get_raw_report(hid, reportnum, buf, len, rtype);
 730         case HID_REQ_SET_REPORT:
 731                 if (buf[0] != reportnum)
 732                         return -EINVAL;
 733                 return i2c_hid_output_raw_report(hid, buf, len, rtype, true);
 734         default:
 735                 return -EIO;
 736         }
 737 }
 738
 739 static int i2c_hid_parse(struct hid_device *hid)
 740 {
 741         struct i2c_client *client = hid->driver_data;
 742         struct i2c_hid *ihid = i2c_get_clientdata(client);
 743         struct i2c_hid_desc *hdesc = &ihid->hdesc;
 744         unsigned int rsize;
 745         char *rdesc;
 746         int ret;
 747         int tries = 3;
 748         char *use_override;
 749
 750         i2c_hid_dbg(ihid, "entering %s\n", __func__);
 751
 752         rsize = le16_to_cpu(hdesc->wReportDescLength);
 753         if (!rsize || rsize > HID_MAX_DESCRIPTOR_SIZE) {
 754                 dbg_hid("weird size of report descriptor (%u)\n", rsize);
 755                 return -EINVAL;
 756         }
 757
 758         do {
 759                 ret = i2c_hid_hwreset(client);
 760                 if (ret)
 761                         msleep(1000);
 762         } while (tries-- > 0 && ret);
 763
 764         if (ret)
 765                 return ret;
 766
 767         use_override = i2c_hid_get_dmi_hid_report_desc_override(client->name,
 768                                                                 &rsize);
 769
 770         if (use_override) {
 771                 rdesc = use_override;
 772                 i2c_hid_dbg(ihid, "Using a HID report descriptor override\n");
 773         } else {
 774                 rdesc = kzalloc(rsize, GFP_KERNEL);
 775
 776                 if (!rdesc) {
 777                         dbg_hid("couldn't allocate rdesc memory\n");
 778                         return -ENOMEM;
 779                 }
 780
 781                 i2c_hid_dbg(ihid, "asking HID report descriptor\n");
 782
 783                 ret = i2c_hid_command(client, &hid_report_descr_cmd,
 784                                       rdesc, rsize);
 785                 if (ret) {
 786                         hid_err(hid, "reading report descriptor failed\n");
 787                         kfree(rdesc);
 788                         return -EIO;
 789                 }
 790         }
 791
 792         i2c_hid_dbg(ihid, "Report Descriptor: %*ph\n", rsize, rdesc);
 793
 794         ret = hid_parse_report(hid, rdesc, rsize);
 795         if (!use_override)
 796                 kfree(rdesc);
 797
 798         if (ret) {
 799                 dbg_hid("parsing report descriptor failed\n");
 800                 return ret;
 801         }
 802
 803         return 0;
 804 }
 805
 806 static int i2c_hid_start(struct hid_device *hid)
 807 {
 808         struct i2c_client *client = hid->driver_data;
 809         struct i2c_hid *ihid = i2c_get_clientdata(client);
 810         int ret;
 811         unsigned int bufsize = HID_MIN_BUFFER_SIZE;
 812
 813         i2c_hid_find_max_report(hid, HID_INPUT_REPORT, &bufsize);
 814         i2c_hid_find_max_report(hid, HID_OUTPUT_REPORT, &bufsize);
 815         i2c_hid_find_max_report(hid, HID_FEATURE_REPORT, &bufsize);
 816
 817         if (bufsize > ihid->bufsize) {
 818                 i2c_hid_free_buffers(ihid);
 819
 820                 ret = i2c_hid_alloc_buffers(ihid, bufsize);
 821
 822                 if (ret)
 823                         return ret;
 824         }
 825
 826         if (!(hid->quirks & HID_QUIRK_NO_INIT_REPORTS))
 827                 i2c_hid_init_reports(hid);
 828
 829         return 0;
 830 }
 831
 832 static void i2c_hid_stop(struct hid_device *hid)
 833 {
 834         hid->claimed = 0;
 835 }
 836
 837 static int i2c_hid_open(struct hid_device *hid)
 838 {
 839         struct i2c_client *client = hid->driver_data;
 840         struct i2c_hid *ihid = i2c_get_clientdata(client);
 841         int ret = 0;
 842
 843         mutex_lock(&i2c_hid_open_mut);
 844         if (!hid->open++) {
 845                 ret = pm_runtime_get_sync(&client->dev);
 846                 if (ret < 0) {
 847                         hid->open--;
 848                         goto done;
 849                 }
 850                 set_bit(I2C_HID_STARTED, &ihid->flags);
 851         }
 852 done:
 853         mutex_unlock(&i2c_hid_open_mut);
 854         return ret < 0 ? ret : 0;
 855 }
 856
 857 static void i2c_hid_close(struct hid_device *hid)
 858 {
 859         struct i2c_client *client = hid->driver_data;
 860         struct i2c_hid *ihid = i2c_get_clientdata(client);
 861
 862         /* protecting hid->open to make sure we don't restart
 863          * data acquistion due to a resumption we no longer
 864          * care about
 865          */
 866         mutex_lock(&i2c_hid_open_mut);
 867         if (!--hid->open) {
 868                 clear_bit(I2C_HID_STARTED, &ihid->flags);
 869
 870                 /* Save some power */
 871                 pm_runtime_put(&client->dev);
 872         }
 873         mutex_unlock(&i2c_hid_open_mut);
 874 }
 875
 876 static int i2c_hid_power(struct hid_device *hid, int lvl)
 877 {
 878         struct i2c_client *client = hid->driver_data;
 879         struct i2c_hid *ihid = i2c_get_clientdata(client);
 880
 881         i2c_hid_dbg(ihid, "%s lvl:%d\n", __func__, lvl);
 882
 883         switch (lvl) {
 884         case PM_HINT_FULLON:
 885                 pm_runtime_get_sync(&client->dev);
 886                 break;
 887         case PM_HINT_NORMAL:
 888                 pm_runtime_put(&client->dev);
 889                 break;
 890         }
 891         return 0;
 892 }
 893
 894 struct hid_ll_driver i2c_hid_ll_driver = {
 895         .parse = i2c_hid_parse,
 896         .start = i2c_hid_start,
 897         .stop = i2c_hid_stop,
 898         .open = i2c_hid_open,
 899         .close = i2c_hid_close,
 900         .power = i2c_hid_power,
 901         .output_report = i2c_hid_output_report,
 902         .raw_request = i2c_hid_raw_request,
 903 };
 904 EXPORT_SYMBOL_GPL(i2c_hid_ll_driver);
 905
 906 static int i2c_hid_init_irq(struct i2c_client *client)
 907 {
 908         struct i2c_hid *ihid = i2c_get_clientdata(client);
 909         int ret;
 910
 911         dev_dbg(&client->dev, "Requesting IRQ: %d\n", ihid->irq);
 912
 913         ret = request_threaded_irq(ihid->irq, NULL, i2c_hid_irq,
 914                         IRQF_TRIGGER_LOW | IRQF_ONESHOT,
 915                         client->name, ihid);
 916         if (ret < 0) {
 917                 dev_warn(&client->dev,
 918                         "Could not register for %s interrupt, irq = %d,"
 919                         " ret = %d\n",
 920                         client->name, ihid->irq, ret);
 921
 922                 return ret;
 923         }
 924
 925         return 0;
 926 }
 927
 928 static int i2c_hid_fetch_hid_descriptor(struct i2c_hid *ihid)
 929 {
 930         struct i2c_client *client = ihid->client;
 931         struct i2c_hid_desc *hdesc = &ihid->hdesc;
 932         unsigned int dsize;
 933         int ret;
 934
 935         /* i2c hid fetch using a fixed descriptor size (30 bytes) */
 936         if (i2c_hid_get_dmi_i2c_hid_desc_override(client->name)) {
 937                 i2c_hid_dbg(ihid, "Using a HID descriptor override\n");
 938                 ihid->hdesc =
 939                         *i2c_hid_get_dmi_i2c_hid_desc_override(client->name);
 940         } else {
 941                 i2c_hid_dbg(ihid, "Fetching the HID descriptor\n");
 942                 ret = i2c_hid_command(client, &hid_descr_cmd,
 943                                       ihid->hdesc_buffer,
 944                                       sizeof(struct i2c_hid_desc));
 945                 if (ret) {
 946                         dev_err(&client->dev, "hid_descr_cmd failed\n");
 947                         return -ENODEV;
 948                 }
 949         }
 950
 951         /* Validate the length of HID descriptor, the 4 first bytes:
 952          * bytes 0-1 -> length
 953          * bytes 2-3 -> bcdVersion (has to be 1.00) */
 954         /* check bcdVersion == 1.0 */
 955         if (le16_to_cpu(hdesc->bcdVersion) != 0x0100) {
 956                 dev_err(&client->dev,
 957                         "unexpected HID descriptor bcdVersion (0x%04hx)\n",
 958                         le16_to_cpu(hdesc->bcdVersion));
 959                 return -ENODEV;
 960         }
 961
 962         /* Descriptor length should be 30 bytes as per the specification */
 963         dsize = le16_to_cpu(hdesc->wHIDDescLength);
 964         if (dsize != sizeof(struct i2c_hid_desc)) {
 965                 dev_err(&client->dev, "weird size of HID descriptor (%u)\n",
 966                         dsize);
 967                 return -ENODEV;
 968         }
 969         i2c_hid_dbg(ihid, "HID Descriptor: %*ph\n", dsize, ihid->hdesc_buffer);
 970         return 0;
 971 }
 972
 973 #ifdef CONFIG_ACPI
 974
 975 /* Default GPIO mapping */
 976 static const struct acpi_gpio_params i2c_hid_irq_gpio = { 0, 0, true };
 977 static const struct acpi_gpio_mapping i2c_hid_acpi_gpios[] = {
 978         { "gpios", &i2c_hid_irq_gpio, 1 },
 979         { },
 980 };
 981
 982 static int i2c_hid_acpi_pdata(struct i2c_client *client,
 983                 struct i2c_hid_platform_data *pdata)
 984 {
 985         static u8 i2c_hid_guid[] = {
 986                 0xF7, 0xF6, 0xDF, 0x3C, 0x67, 0x42, 0x55, 0x45,
 987                 0xAD, 0x05, 0xB3, 0x0A, 0x3D, 0x89, 0x38, 0xDE,
 988         };
 989         union acpi_object *obj;
 990         struct acpi_device *adev;
 991         acpi_handle handle;
 992         int ret;
 993
 994         handle = ACPI_HANDLE(&client->dev);
 995         if (!handle || acpi_bus_get_device(handle, &adev))
 996                 return -ENODEV;
 997
 998         obj = acpi_evaluate_dsm_typed(handle, i2c_hid_guid, 1, 1, NULL,
 999                                       ACPI_TYPE_INTEGER);
1000         if (!obj) {
1001                 dev_err(&client->dev, "device _DSM execution failed\n");
1002                 return -ENODEV;
1003         }
1004
1005         pdata->hid_descriptor_address = obj->integer.value;
1006         ACPI_FREE(obj);
1007
1008         /* GPIOs are optional */
1009         ret = acpi_dev_add_driver_gpios(adev, i2c_hid_acpi_gpios);
1010         return ret < 0 && ret != -ENXIO ? ret : 0;
1011 }
1012
1013 static void i2c_hid_acpi_fix_up_power(struct device *dev)
1014 {
1015         acpi_handle handle = ACPI_HANDLE(dev);
1016         struct acpi_device *adev;
1017
1018         if (handle && acpi_bus_get_device(handle, &adev) == 0)
1019                 acpi_device_fix_up_power(adev);
1020 }
1021
1022 static const struct acpi_device_id i2c_hid_acpi_match[] = {
1023         {"ACPI0C50", 0 },
1024         {"PNP0C50", 0 },
1025         { },
1026 };
1027 MODULE_DEVICE_TABLE(acpi, i2c_hid_acpi_match);
1028 #else
1029 static inline int i2c_hid_acpi_pdata(struct i2c_client *client,
1030                 struct i2c_hid_platform_data *pdata)
1031 {
1032         return -ENODEV;
1033 }
1034
1035 static inline void i2c_hid_acpi_fix_up_power(struct device *dev) {}
1036 #endif
1037
1038 #ifdef CONFIG_OF
1039 static int i2c_hid_of_probe(struct i2c_client *client,
1040                 struct i2c_hid_platform_data *pdata)
1041 {
1042         struct device *dev = &client->dev;
1043         u32 val;
1044         int ret;
1045
1046         ret = of_property_read_u32(dev->of_node, "hid-descr-addr", &val);
1047         if (ret) {
1048                 dev_err(&client->dev, "HID register address not provided\n");
1049                 return -ENODEV;
1050         }
1051         if (val >> 16) {
1052                 dev_err(&client->dev, "Bad HID register address: 0x%08x\n",
1053                         val);
1054                 return -EINVAL;
1055         }
1056         pdata->hid_descriptor_address = val;
1057
1058         return 0;
1059 }
1060
1061 static const struct of_device_id i2c_hid_of_match[] = {
1062         { .compatible = "hid-over-i2c" },
1063         {},
1064 };
1065 MODULE_DEVICE_TABLE(of, i2c_hid_of_match);
1066 #else
1067 static inline int i2c_hid_of_probe(struct i2c_client *client,
1068                 struct i2c_hid_platform_data *pdata)
1069 {
1070         return -ENODEV;
1071 }
1072 #endif
1073
1074 static int i2c_hid_probe(struct i2c_client *client,
1075                          const struct i2c_device_id *dev_id)
1076 {
1077         int ret;
1078         struct i2c_hid *ihid;
1079         struct hid_device *hid;
1080         __u16 hidRegister;
1081         struct i2c_hid_platform_data *platform_data = client->dev.platform_data;
1082
1083         dbg_hid("HID probe called for i2c 0x%02x\n", client->addr);
1084
1085         ihid = kzalloc(sizeof(struct i2c_hid), GFP_KERNEL);
1086         if (!ihid)
1087                 return -ENOMEM;
1088
1089         if (client->dev.of_node) {
1090                 ret = i2c_hid_of_probe(client, &ihid->pdata);
1091                 if (ret)
1092                         goto err;
1093         } else if (!platform_data) {
1094                 ret = i2c_hid_acpi_pdata(client, &ihid->pdata);
1095                 if (ret) {
1096                         dev_err(&client->dev,
1097                                 "HID register address not provided\n");
1098                         goto err;
1099                 }
1100         } else {
1101                 ihid->pdata = *platform_data;
1102         }
1103
1104         if (client->irq > 0) {
1105                 ihid->irq = client->irq;
1106         } else if (ACPI_COMPANION(&client->dev)) {
1107                 ihid->desc = gpiod_get(&client->dev, NULL, GPIOD_IN);
1108                 if (IS_ERR(ihid->desc)) {
1109                         dev_err(&client->dev, "Failed to get GPIO interrupt\n");
1110                         return PTR_ERR(ihid->desc);
1111                 }
1112
1113                 ihid->irq = gpiod_to_irq(ihid->desc);
1114                 if (ihid->irq < 0) {
1115                         gpiod_put(ihid->desc);
1116                         dev_err(&client->dev, "Failed to convert GPIO to IRQ\n");
1117                         return ihid->irq;
1118                 }
1119         }
1120
1121         i2c_set_clientdata(client, ihid);
1122
1123         ihid->client = client;
1124
1125         hidRegister = ihid->pdata.hid_descriptor_address;
1126         ihid->wHIDDescRegister = cpu_to_le16(hidRegister);
1127
1128         init_waitqueue_head(&ihid->wait);
1129         mutex_init(&ihid->reset_lock);
1130
1131         /* we need to allocate the command buffer without knowing the maximum
1132          * size of the reports. Let's use HID_MIN_BUFFER_SIZE, then we do the
1133          * real computation later. */
1134         ret = i2c_hid_alloc_buffers(ihid, HID_MIN_BUFFER_SIZE);
1135         if (ret < 0)
1136                 goto err;
1137
1138         i2c_hid_acpi_fix_up_power(&client->dev);
1139
1140         pm_runtime_get_noresume(&client->dev);
1141         pm_runtime_set_active(&client->dev);
1142         pm_runtime_enable(&client->dev);
1143         device_enable_async_suspend(&client->dev);
1144
1145         /* Make sure there is something at this address */
1146         ret = i2c_smbus_read_byte(client);
1147         if (ret < 0) {
1148                 dev_dbg(&client->dev, "nothing at this address: %d\n", ret);
1149                 ret = -ENXIO;
1150                 goto err_pm;
1151         }
1152
1153         ret = i2c_hid_fetch_hid_descriptor(ihid);
1154         if (ret < 0)
1155                 goto err_pm;
1156
1157         ret = i2c_hid_init_irq(client);
1158         if (ret < 0)
1159                 goto err_pm;
1160
1161         hid = hid_allocate_device();
1162         if (IS_ERR(hid)) {
1163                 ret = PTR_ERR(hid);
1164                 goto err_irq;
1165         }
1166
1167         ihid->hid = hid;
1168
1169         hid->driver_data = client;
1170         hid->ll_driver = &i2c_hid_ll_driver;
1171         hid->dev.parent = &client->dev;
1172         hid->bus = BUS_I2C;
1173         hid->version = le16_to_cpu(ihid->hdesc.bcdVersion);
1174         hid->vendor = le16_to_cpu(ihid->hdesc.wVendorID);
1175         hid->product = le16_to_cpu(ihid->hdesc.wProductID);
1176
1177         snprintf(hid->name, sizeof(hid->name), "%s %04X:%04X",
1178                  client->name, (u16)hid->vendor, (u16)hid->product);
1179         strlcpy(hid->phys, dev_name(&client->dev), sizeof(hid->phys));
1180
1181         ihid->quirks = i2c_hid_lookup_quirk(hid->vendor, hid->product);
1182
1183         ret = hid_add_device(hid);
1184         if (ret) {
1185                 if (ret != -ENODEV)
1186                         hid_err(client, "can't add hid device: %d\n", ret);
1187                 goto err_mem_free;
1188         }
1189
1190         pm_runtime_put(&client->dev);
1191         return 0;
1192
1193 err_mem_free:
1194         hid_destroy_device(hid);
1195
1196 err_irq:
1197         free_irq(ihid->irq, ihid);
1198
1199 err_pm:
1200         pm_runtime_put_noidle(&client->dev);
1201         pm_runtime_disable(&client->dev);
1202
1203 err:
1204         if (ihid->desc)
1205                 gpiod_put(ihid->desc);
1206
1207         i2c_hid_free_buffers(ihid);
1208         kfree(ihid);
1209         return ret;
1210 }
1211
1212 static int i2c_hid_remove(struct i2c_client *client)
1213 {
1214         struct i2c_hid *ihid = i2c_get_clientdata(client);
1215         struct hid_device *hid;
1216
1217         pm_runtime_get_sync(&client->dev);
1218         pm_runtime_disable(&client->dev);
1219         pm_runtime_set_suspended(&client->dev);
1220         pm_runtime_put_noidle(&client->dev);
1221
1222         hid = ihid->hid;
1223         hid_destroy_device(hid);
1224
1225         free_irq(ihid->irq, ihid);
1226
1227         if (ihid->bufsize)
1228                 i2c_hid_free_buffers(ihid);
1229
1230         if (ihid->desc)
1231                 gpiod_put(ihid->desc);
1232
1233         kfree(ihid);
1234
1235         acpi_dev_remove_driver_gpios(ACPI_COMPANION(&client->dev));
1236
1237         return 0;
1238 }
1239
1240 static void i2c_hid_shutdown(struct i2c_client *client)
1241 {
1242         struct i2c_hid *ihid = i2c_get_clientdata(client);
1243
1244         i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
1245         free_irq(client->irq, ihid);
1246 }
1247
1248 #ifdef CONFIG_PM_SLEEP
1249 static int i2c_hid_suspend(struct device *dev)
1250 {
1251         struct i2c_client *client = to_i2c_client(dev);
1252         struct i2c_hid *ihid = i2c_get_clientdata(client);
1253         struct hid_device *hid = ihid->hid;
1254         int ret;
1255         int wake_status;
1256
1257         if (hid->driver && hid->driver->suspend) {
1258                 /*
1259                  * Wake up the device so that IO issues in
1260                  * HID driver's suspend code can succeed.
1261                  */
1262                 ret = pm_runtime_resume(dev);
1263                 if (ret < 0)
1264                         return ret;
1265
1266                 ret = hid->driver->suspend(hid, PMSG_SUSPEND);
1267                 if (ret < 0)
1268                         return ret;
1269         }
1270
1271         if (!pm_runtime_suspended(dev)) {
1272                 /* Save some power */
1273                 i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
1274
1275                 disable_irq(ihid->irq);
1276         }
1277
1278         if (device_may_wakeup(&client->dev)) {
1279                 wake_status = enable_irq_wake(ihid->irq);
1280                 if (!wake_status)
1281                         ihid->irq_wake_enabled = true;
1282                 else
1283                         hid_warn(hid, "Failed to enable irq wake: %d\n",
1284                                 wake_status);
1285         }
1286
1287         return 0;
1288 }
1289
1290 static int i2c_hid_resume(struct device *dev)
1291 {
1292         int ret;
1293         struct i2c_client *client = to_i2c_client(dev);
1294         struct i2c_hid *ihid = i2c_get_clientdata(client);
1295         struct hid_device *hid = ihid->hid;
1296         int wake_status;
1297
1298         if (device_may_wakeup(&client->dev) && ihid->irq_wake_enabled) {
1299                 wake_status = disable_irq_wake(ihid->irq);
1300                 if (!wake_status)
1301                         ihid->irq_wake_enabled = false;
1302                 else
1303                         hid_warn(hid, "Failed to disable irq wake: %d\n",
1304                                 wake_status);
1305         }
1306
1307         /* We'll resume to full power */
1308         pm_runtime_disable(dev);
1309         pm_runtime_set_active(dev);
1310         pm_runtime_enable(dev);
1311
1312         enable_irq(ihid->irq);
1313         ret = i2c_hid_hwreset(client);
1314         if (ret)
1315                 return ret;
1316
1317         if (hid->driver && hid->driver->reset_resume) {
1318                 ret = hid->driver->reset_resume(hid);
1319                 return ret;
1320         }
1321
1322         return 0;
1323 }
1324 #endif
1325
1326 #ifdef CONFIG_PM
1327 static int i2c_hid_runtime_suspend(struct device *dev)
1328 {
1329         struct i2c_client *client = to_i2c_client(dev);
1330         struct i2c_hid *ihid = i2c_get_clientdata(client);
1331
1332         i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
1333         disable_irq(ihid->irq);
1334         return 0;
1335 }
1336
1337 static int i2c_hid_runtime_resume(struct device *dev)
1338 {
1339         struct i2c_client *client = to_i2c_client(dev);
1340         struct i2c_hid *ihid = i2c_get_clientdata(client);
1341
1342         enable_irq(ihid->irq);
1343         i2c_hid_set_power(client, I2C_HID_PWR_ON);
1344         return 0;
1345 }
1346 #endif
1347
1348 static const struct dev_pm_ops i2c_hid_pm = {
1349         SET_SYSTEM_SLEEP_PM_OPS(i2c_hid_suspend, i2c_hid_resume)
1350         SET_RUNTIME_PM_OPS(i2c_hid_runtime_suspend, i2c_hid_runtime_resume,
1351                            NULL)
1352 };
1353
1354 static const struct i2c_device_id i2c_hid_id_table[] = {
1355         { "hid", 0 },
1356         { "hid-over-i2c", 0 },
1357         { },
1358 };
1359 MODULE_DEVICE_TABLE(i2c, i2c_hid_id_table);
1360
1361
1362 static struct i2c_driver i2c_hid_driver = {
1363         .driver = {
1364                 .name   = "i2c_hid",
1365                 .pm     = &i2c_hid_pm,
1366                 .acpi_match_table = ACPI_PTR(i2c_hid_acpi_match),
1367                 .of_match_table = of_match_ptr(i2c_hid_of_match),
1368         },
1369
1370         .probe          = i2c_hid_probe,
1371         .remove         = i2c_hid_remove,
1372         .shutdown       = i2c_hid_shutdown,
1373         .id_table       = i2c_hid_id_table,
1374 };
1375
1376 module_i2c_driver(i2c_hid_driver);
1377
1378 MODULE_DESCRIPTION("HID over I2C core driver");
1379 MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
1380 MODULE_LICENSE("GPL");