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/irq.h>
  26 #include <linux/delay.h>
  27 #include <linux/slab.h>
  28 #include <linux/pm.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/regulator/consumer.h>
  41
  42 #include <linux/platform_data/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 #define I2C_HID_QUIRK_NO_IRQ_AFTER_RESET        BIT(1)
  50 #define I2C_HID_QUIRK_BOGUS_IRQ                 BIT(4)
  51 #define I2C_HID_QUIRK_RESET_ON_RESUME           BIT(5)
  52 #define I2C_HID_QUIRK_BAD_INPUT_SIZE            BIT(6)
  53 #define I2C_HID_QUIRK_NO_WAKEUP_AFTER_RESET     BIT(7)
  54
  55
  56 /* flags */
  57 #define I2C_HID_STARTED         0
  58 #define I2C_HID_RESET_PENDING   1
  59 #define I2C_HID_READ_PENDING    2
  60
  61 #define I2C_HID_PWR_ON          0x00
  62 #define I2C_HID_PWR_SLEEP       0x01
  63
  64 /* debug option */
  65 static bool debug;
  66 module_param(debug, bool, 0444);
  67 MODULE_PARM_DESC(debug, "print a lot of debug information");
  68
  69 #define i2c_hid_dbg(ihid, fmt, arg...)                                    \
  70 do {                                                                      \
  71         if (debug)                                                        \
  72                 dev_printk(KERN_DEBUG, &(ihid)->client->dev, fmt, ##arg); \
  73 } while (0)
  74
  75 struct i2c_hid_desc {
  76         __le16 wHIDDescLength;
  77         __le16 bcdVersion;
  78         __le16 wReportDescLength;
  79         __le16 wReportDescRegister;
  80         __le16 wInputRegister;
  81         __le16 wMaxInputLength;
  82         __le16 wOutputRegister;
  83         __le16 wMaxOutputLength;
  84         __le16 wCommandRegister;
  85         __le16 wDataRegister;
  86         __le16 wVendorID;
  87         __le16 wProductID;
  88         __le16 wVersionID;
  89         __le32 reserved;
  90 } __packed;
  91
  92 struct i2c_hid_cmd {
  93         unsigned int registerIndex;
  94         __u8 opcode;
  95         unsigned int length;
  96         bool wait;
  97 };
  98
  99 union command {
 100         u8 data[0];
 101         struct cmd {
 102                 __le16 reg;
 103                 __u8 reportTypeID;
 104                 __u8 opcode;
 105         } __packed c;
 106 };
 107
 108 #define I2C_HID_CMD(opcode_) \
 109         .opcode = opcode_, .length = 4, \
 110         .registerIndex = offsetof(struct i2c_hid_desc, wCommandRegister)
 111
 112 /* fetch HID descriptor */
 113 static const struct i2c_hid_cmd hid_descr_cmd = { .length = 2 };
 114 /* fetch report descriptors */
 115 static const struct i2c_hid_cmd hid_report_descr_cmd = {
 116                 .registerIndex = offsetof(struct i2c_hid_desc,
 117                         wReportDescRegister),
 118                 .opcode = 0x00,
 119                 .length = 2 };
 120 /* commands */
 121 static const struct i2c_hid_cmd hid_reset_cmd =         { I2C_HID_CMD(0x01),
 122                                                           .wait = true };
 123 static const struct i2c_hid_cmd hid_get_report_cmd =    { I2C_HID_CMD(0x02) };
 124 static const struct i2c_hid_cmd hid_set_report_cmd =    { I2C_HID_CMD(0x03) };
 125 static const struct i2c_hid_cmd hid_set_power_cmd =     { I2C_HID_CMD(0x08) };
 126 static const struct i2c_hid_cmd hid_no_cmd =            { .length = 0 };
 127
 128 /*
 129  * These definitions are not used here, but are defined by the spec.
 130  * Keeping them here for documentation purposes.
 131  *
 132  * static const struct i2c_hid_cmd hid_get_idle_cmd = { I2C_HID_CMD(0x04) };
 133  * static const struct i2c_hid_cmd hid_set_idle_cmd = { I2C_HID_CMD(0x05) };
 134  * static const struct i2c_hid_cmd hid_get_protocol_cmd = { I2C_HID_CMD(0x06) };
 135  * static const struct i2c_hid_cmd hid_set_protocol_cmd = { I2C_HID_CMD(0x07) };
 136  */
 137
 138 /* The main device structure */
 139 struct i2c_hid {
 140         struct i2c_client       *client;        /* i2c client */
 141         struct hid_device       *hid;   /* pointer to corresponding HID dev */
 142         union {
 143                 __u8 hdesc_buffer[sizeof(struct i2c_hid_desc)];
 144                 struct i2c_hid_desc hdesc;      /* the HID Descriptor */
 145         };
 146         __le16                  wHIDDescRegister; /* location of the i2c
 147                                                    * register of the HID
 148                                                    * descriptor. */
 149         unsigned int            bufsize;        /* i2c buffer size */
 150         u8                      *inbuf;         /* Input buffer */
 151         u8                      *rawbuf;        /* Raw Input buffer */
 152         u8                      *cmdbuf;        /* Command buffer */
 153         u8                      *argsbuf;       /* Command arguments buffer */
 154
 155         unsigned long           flags;          /* device flags */
 156         unsigned long           quirks;         /* Various quirks */
 157
 158         wait_queue_head_t       wait;           /* For waiting the interrupt */
 159
 160         struct i2c_hid_platform_data pdata;
 161
 162         bool                    irq_wake_enabled;
 163         struct mutex            reset_lock;
 164 };
 165
 166 static const struct i2c_hid_quirks {
 167         __u16 idVendor;
 168         __u16 idProduct;
 169         __u32 quirks;
 170 } i2c_hid_quirks[] = {
 171         { USB_VENDOR_ID_WEIDA, HID_ANY_ID,
 172                 I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV },
 173         { I2C_VENDOR_ID_HANTICK, I2C_PRODUCT_ID_HANTICK_5288,
 174                 I2C_HID_QUIRK_NO_IRQ_AFTER_RESET },
 175         { I2C_VENDOR_ID_ITE, I2C_DEVICE_ID_ITE_VOYO_WINPAD_A15,
 176                 I2C_HID_QUIRK_NO_IRQ_AFTER_RESET },
 177         { I2C_VENDOR_ID_RAYDIUM, I2C_PRODUCT_ID_RAYDIUM_3118,
 178                 I2C_HID_QUIRK_NO_IRQ_AFTER_RESET },
 179         { USB_VENDOR_ID_ALPS_JP, HID_ANY_ID,
 180                  I2C_HID_QUIRK_RESET_ON_RESUME },
 181         { I2C_VENDOR_ID_SYNAPTICS, I2C_PRODUCT_ID_SYNAPTICS_SYNA2393,
 182                  I2C_HID_QUIRK_RESET_ON_RESUME },
 183         { USB_VENDOR_ID_ITE, I2C_DEVICE_ID_ITE_LENOVO_LEGION_Y720,
 184                 I2C_HID_QUIRK_BAD_INPUT_SIZE },
 185         /*
 186          * Sending the wakeup after reset actually break ELAN touchscreen controller
 187          */
 188         { USB_VENDOR_ID_ELAN, HID_ANY_ID,
 189                  I2C_HID_QUIRK_NO_WAKEUP_AFTER_RESET |
 190                  I2C_HID_QUIRK_BOGUS_IRQ },
 191         { 0, 0 }
 192 };
 193
 194 /*
 195  * i2c_hid_lookup_quirk: return any quirks associated with a I2C HID device
 196  * @idVendor: the 16-bit vendor ID
 197  * @idProduct: the 16-bit product ID
 198  *
 199  * Returns: a u32 quirks value.
 200  */
 201 static u32 i2c_hid_lookup_quirk(const u16 idVendor, const u16 idProduct)
 202 {
 203         u32 quirks = 0;
 204         int n;
 205
 206         for (n = 0; i2c_hid_quirks[n].idVendor; n++)
 207                 if (i2c_hid_quirks[n].idVendor == idVendor &&
 208                     (i2c_hid_quirks[n].idProduct == (__u16)HID_ANY_ID ||
 209                      i2c_hid_quirks[n].idProduct == idProduct))
 210                         quirks = i2c_hid_quirks[n].quirks;
 211
 212         return quirks;
 213 }
 214
 215 static int __i2c_hid_command(struct i2c_client *client,
 216                 const struct i2c_hid_cmd *command, u8 reportID,
 217                 u8 reportType, u8 *args, int args_len,
 218                 unsigned char *buf_recv, int data_len)
 219 {
 220         struct i2c_hid *ihid = i2c_get_clientdata(client);
 221         union command *cmd = (union command *)ihid->cmdbuf;
 222         int ret;
 223         struct i2c_msg msg[2];
 224         int msg_num = 1;
 225
 226         int length = command->length;
 227         bool wait = command->wait;
 228         unsigned int registerIndex = command->registerIndex;
 229
 230         /* special case for hid_descr_cmd */
 231         if (command == &hid_descr_cmd) {
 232                 cmd->c.reg = ihid->wHIDDescRegister;
 233         } else {
 234                 cmd->data[0] = ihid->hdesc_buffer[registerIndex];
 235                 cmd->data[1] = ihid->hdesc_buffer[registerIndex + 1];
 236         }
 237
 238         if (length > 2) {
 239                 cmd->c.opcode = command->opcode;
 240                 cmd->c.reportTypeID = reportID | reportType << 4;
 241         }
 242
 243         memcpy(cmd->data + length, args, args_len);
 244         length += args_len;
 245
 246         i2c_hid_dbg(ihid, "%s: cmd=%*ph\n", __func__, length, cmd->data);
 247
 248         msg[0].addr = client->addr;
 249         msg[0].flags = client->flags & I2C_M_TEN;
 250         msg[0].len = length;
 251         msg[0].buf = cmd->data;
 252         if (data_len > 0) {
 253                 msg[1].addr = client->addr;
 254                 msg[1].flags = client->flags & I2C_M_TEN;
 255                 msg[1].flags |= I2C_M_RD;
 256                 msg[1].len = data_len;
 257                 msg[1].buf = buf_recv;
 258                 msg_num = 2;
 259                 set_bit(I2C_HID_READ_PENDING, &ihid->flags);
 260         }
 261
 262         if (wait)
 263                 set_bit(I2C_HID_RESET_PENDING, &ihid->flags);
 264
 265         ret = i2c_transfer(client->adapter, msg, msg_num);
 266
 267         if (data_len > 0)
 268                 clear_bit(I2C_HID_READ_PENDING, &ihid->flags);
 269
 270         if (ret != msg_num)
 271                 return ret < 0 ? ret : -EIO;
 272
 273         ret = 0;
 274
 275         if (wait && (ihid->quirks & I2C_HID_QUIRK_NO_IRQ_AFTER_RESET)) {
 276                 msleep(100);
 277         } else if (wait) {
 278                 i2c_hid_dbg(ihid, "%s: waiting...\n", __func__);
 279                 if (!wait_event_timeout(ihid->wait,
 280                                 !test_bit(I2C_HID_RESET_PENDING, &ihid->flags),
 281                                 msecs_to_jiffies(5000)))
 282                         ret = -ENODATA;
 283                 i2c_hid_dbg(ihid, "%s: finished.\n", __func__);
 284         }
 285
 286         return ret;
 287 }
 288
 289 static int i2c_hid_command(struct i2c_client *client,
 290                 const struct i2c_hid_cmd *command,
 291                 unsigned char *buf_recv, int data_len)
 292 {
 293         return __i2c_hid_command(client, command, 0, 0, NULL, 0,
 294                                 buf_recv, data_len);
 295 }
 296
 297 static int i2c_hid_get_report(struct i2c_client *client, u8 reportType,
 298                 u8 reportID, unsigned char *buf_recv, int data_len)
 299 {
 300         struct i2c_hid *ihid = i2c_get_clientdata(client);
 301         u8 args[3];
 302         int ret;
 303         int args_len = 0;
 304         u16 readRegister = le16_to_cpu(ihid->hdesc.wDataRegister);
 305
 306         i2c_hid_dbg(ihid, "%s\n", __func__);
 307
 308         if (reportID >= 0x0F) {
 309                 args[args_len++] = reportID;
 310                 reportID = 0x0F;
 311         }
 312
 313         args[args_len++] = readRegister & 0xFF;
 314         args[args_len++] = readRegister >> 8;
 315
 316         ret = __i2c_hid_command(client, &hid_get_report_cmd, reportID,
 317                 reportType, args, args_len, buf_recv, data_len);
 318         if (ret) {
 319                 dev_err(&client->dev,
 320                         "failed to retrieve report from device.\n");
 321                 return ret;
 322         }
 323
 324         return 0;
 325 }
 326
 327 /**
 328  * i2c_hid_set_or_send_report: forward an incoming report to the device
 329  * @client: the i2c_client of the device
 330  * @reportType: 0x03 for HID_FEATURE_REPORT ; 0x02 for HID_OUTPUT_REPORT
 331  * @reportID: the report ID
 332  * @buf: the actual data to transfer, without the report ID
 333  * @data_len: size of buf
 334  * @use_data: true: use SET_REPORT HID command, false: send plain OUTPUT report
 335  */
 336 static int i2c_hid_set_or_send_report(struct i2c_client *client, u8 reportType,
 337                 u8 reportID, unsigned char *buf, size_t data_len, bool use_data)
 338 {
 339         struct i2c_hid *ihid = i2c_get_clientdata(client);
 340         u8 *args = ihid->argsbuf;
 341         const struct i2c_hid_cmd *hidcmd;
 342         int ret;
 343         u16 dataRegister = le16_to_cpu(ihid->hdesc.wDataRegister);
 344         u16 outputRegister = le16_to_cpu(ihid->hdesc.wOutputRegister);
 345         u16 maxOutputLength = le16_to_cpu(ihid->hdesc.wMaxOutputLength);
 346         u16 size;
 347         int args_len;
 348         int index = 0;
 349
 350         i2c_hid_dbg(ihid, "%s\n", __func__);
 351
 352         if (data_len > ihid->bufsize)
 353                 return -EINVAL;
 354
 355         size =          2                       /* size */ +
 356                         (reportID ? 1 : 0)      /* reportID */ +
 357                         data_len                /* buf */;
 358         args_len =      (reportID >= 0x0F ? 1 : 0) /* optional third byte */ +
 359                         2                       /* dataRegister */ +
 360                         size                    /* args */;
 361
 362         if (!use_data && maxOutputLength == 0)
 363                 return -ENOSYS;
 364
 365         if (reportID >= 0x0F) {
 366                 args[index++] = reportID;
 367                 reportID = 0x0F;
 368         }
 369
 370         /*
 371          * use the data register for feature reports or if the device does not
 372          * support the output register
 373          */
 374         if (use_data) {
 375                 args[index++] = dataRegister & 0xFF;
 376                 args[index++] = dataRegister >> 8;
 377                 hidcmd = &hid_set_report_cmd;
 378         } else {
 379                 args[index++] = outputRegister & 0xFF;
 380                 args[index++] = outputRegister >> 8;
 381                 hidcmd = &hid_no_cmd;
 382         }
 383
 384         args[index++] = size & 0xFF;
 385         args[index++] = size >> 8;
 386
 387         if (reportID)
 388                 args[index++] = reportID;
 389
 390         memcpy(&args[index], buf, data_len);
 391
 392         ret = __i2c_hid_command(client, hidcmd, reportID,
 393                 reportType, args, args_len, NULL, 0);
 394         if (ret) {
 395                 dev_err(&client->dev, "failed to set a report to device.\n");
 396                 return ret;
 397         }
 398
 399         return data_len;
 400 }
 401
 402 static int i2c_hid_set_power(struct i2c_client *client, int power_state)
 403 {
 404         struct i2c_hid *ihid = i2c_get_clientdata(client);
 405         int ret;
 406
 407         i2c_hid_dbg(ihid, "%s\n", __func__);
 408
 409         /*
 410          * Some devices require to send a command to wakeup before power on.
 411          * The call will get a return value (EREMOTEIO) but device will be
 412          * triggered and activated. After that, it goes like a normal device.
 413          */
 414         if (power_state == I2C_HID_PWR_ON &&
 415             ihid->quirks & I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV) {
 416                 ret = i2c_hid_command(client, &hid_set_power_cmd, NULL, 0);
 417
 418                 /* Device was already activated */
 419                 if (!ret)
 420                         goto set_pwr_exit;
 421         }
 422
 423         ret = __i2c_hid_command(client, &hid_set_power_cmd, power_state,
 424                 0, NULL, 0, NULL, 0);
 425
 426         if (ret)
 427                 dev_err(&client->dev, "failed to change power setting.\n");
 428
 429 set_pwr_exit:
 430
 431         /*
 432          * The HID over I2C specification states that if a DEVICE needs time
 433          * after the PWR_ON request, it should utilise CLOCK stretching.
 434          * However, it has been observered that the Windows driver provides a
 435          * 1ms sleep between the PWR_ON and RESET requests.
 436          * According to Goodix Windows even waits 60 ms after (other?)
 437          * PWR_ON requests. Testing has confirmed that several devices
 438          * will not work properly without a delay after a PWR_ON request.
 439          */
 440         if (!ret && power_state == I2C_HID_PWR_ON)
 441                 msleep(60);
 442
 443         return ret;
 444 }
 445
 446 static int i2c_hid_hwreset(struct i2c_client *client)
 447 {
 448         struct i2c_hid *ihid = i2c_get_clientdata(client);
 449         int ret;
 450
 451         i2c_hid_dbg(ihid, "%s\n", __func__);
 452
 453         /*
 454          * This prevents sending feature reports while the device is
 455          * being reset. Otherwise we may lose the reset complete
 456          * interrupt.
 457          */
 458         mutex_lock(&ihid->reset_lock);
 459
 460         ret = i2c_hid_set_power(client, I2C_HID_PWR_ON);
 461         if (ret)
 462                 goto out_unlock;
 463
 464         i2c_hid_dbg(ihid, "resetting...\n");
 465
 466         ret = i2c_hid_command(client, &hid_reset_cmd, NULL, 0);
 467         if (ret) {
 468                 dev_err(&client->dev, "failed to reset device.\n");
 469                 i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
 470                 goto out_unlock;
 471         }
 472
 473         /* At least some SIS devices need this after reset */
 474         if (!(ihid->quirks & I2C_HID_QUIRK_NO_WAKEUP_AFTER_RESET))
 475                 ret = i2c_hid_set_power(client, I2C_HID_PWR_ON);
 476
 477 out_unlock:
 478         mutex_unlock(&ihid->reset_lock);
 479         return ret;
 480 }
 481
 482 static void i2c_hid_get_input(struct i2c_hid *ihid)
 483 {
 484         int ret;
 485         u32 ret_size;
 486         int size = le16_to_cpu(ihid->hdesc.wMaxInputLength);
 487
 488         if (size > ihid->bufsize)
 489                 size = ihid->bufsize;
 490
 491         ret = i2c_master_recv(ihid->client, ihid->inbuf, size);
 492         if (ret != size) {
 493                 if (ret < 0)
 494                         return;
 495
 496                 dev_err(&ihid->client->dev, "%s: got %d data instead of %d\n",
 497                         __func__, ret, size);
 498                 return;
 499         }
 500
 501         ret_size = ihid->inbuf[0] | ihid->inbuf[1] << 8;
 502
 503         if (!ret_size) {
 504                 /* host or device initiated RESET completed */
 505                 if (test_and_clear_bit(I2C_HID_RESET_PENDING, &ihid->flags))
 506                         wake_up(&ihid->wait);
 507                 return;
 508         }
 509
 510         if (ihid->quirks & I2C_HID_QUIRK_BOGUS_IRQ && ret_size == 0xffff) {
 511                 dev_warn_once(&ihid->client->dev, "%s: IRQ triggered but "
 512                               "there's no data\n", __func__);
 513                 return;
 514         }
 515
 516         if ((ret_size > size) || (ret_size < 2)) {
 517                 if (ihid->quirks & I2C_HID_QUIRK_BAD_INPUT_SIZE) {
 518                         ihid->inbuf[0] = size & 0xff;
 519                         ihid->inbuf[1] = size >> 8;
 520                         ret_size = size;
 521                 } else {
 522                         dev_err(&ihid->client->dev, "%s: incomplete report (%d/%d)\n",
 523                                 __func__, size, ret_size);
 524                         return;
 525                 }
 526         }
 527
 528         i2c_hid_dbg(ihid, "input: %*ph\n", ret_size, ihid->inbuf);
 529
 530         if (test_bit(I2C_HID_STARTED, &ihid->flags))
 531                 hid_input_report(ihid->hid, HID_INPUT_REPORT, ihid->inbuf + 2,
 532                                 ret_size - 2, 1);
 533
 534         return;
 535 }
 536
 537 static irqreturn_t i2c_hid_irq(int irq, void *dev_id)
 538 {
 539         struct i2c_hid *ihid = dev_id;
 540
 541         if (test_bit(I2C_HID_READ_PENDING, &ihid->flags))
 542                 return IRQ_HANDLED;
 543
 544         i2c_hid_get_input(ihid);
 545
 546         return IRQ_HANDLED;
 547 }
 548
 549 static int i2c_hid_get_report_length(struct hid_report *report)
 550 {
 551         return ((report->size - 1) >> 3) + 1 +
 552                 report->device->report_enum[report->type].numbered + 2;
 553 }
 554
 555 /*
 556  * Traverse the supplied list of reports and find the longest
 557  */
 558 static void i2c_hid_find_max_report(struct hid_device *hid, unsigned int type,
 559                 unsigned int *max)
 560 {
 561         struct hid_report *report;
 562         unsigned int size;
 563
 564         /* We should not rely on wMaxInputLength, as some devices may set it to
 565          * a wrong length. */
 566         list_for_each_entry(report, &hid->report_enum[type].report_list, list) {
 567                 size = i2c_hid_get_report_length(report);
 568                 if (*max < size)
 569                         *max = size;
 570         }
 571 }
 572
 573 static void i2c_hid_free_buffers(struct i2c_hid *ihid)
 574 {
 575         kfree(ihid->inbuf);
 576         kfree(ihid->rawbuf);
 577         kfree(ihid->argsbuf);
 578         kfree(ihid->cmdbuf);
 579         ihid->inbuf = NULL;
 580         ihid->rawbuf = NULL;
 581         ihid->cmdbuf = NULL;
 582         ihid->argsbuf = NULL;
 583         ihid->bufsize = 0;
 584 }
 585
 586 static int i2c_hid_alloc_buffers(struct i2c_hid *ihid, size_t report_size)
 587 {
 588         /* the worst case is computed from the set_report command with a
 589          * reportID > 15 and the maximum report length */
 590         int args_len = sizeof(__u8) + /* ReportID */
 591                        sizeof(__u8) + /* optional ReportID byte */
 592                        sizeof(__u16) + /* data register */
 593                        sizeof(__u16) + /* size of the report */
 594                        report_size; /* report */
 595
 596         ihid->inbuf = kzalloc(report_size, GFP_KERNEL);
 597         ihid->rawbuf = kzalloc(report_size, GFP_KERNEL);
 598         ihid->argsbuf = kzalloc(args_len, GFP_KERNEL);
 599         ihid->cmdbuf = kzalloc(sizeof(union command) + args_len, GFP_KERNEL);
 600
 601         if (!ihid->inbuf || !ihid->rawbuf || !ihid->argsbuf || !ihid->cmdbuf) {
 602                 i2c_hid_free_buffers(ihid);
 603                 return -ENOMEM;
 604         }
 605
 606         ihid->bufsize = report_size;
 607
 608         return 0;
 609 }
 610
 611 static int i2c_hid_get_raw_report(struct hid_device *hid,
 612                 unsigned char report_number, __u8 *buf, size_t count,
 613                 unsigned char report_type)
 614 {
 615         struct i2c_client *client = hid->driver_data;
 616         struct i2c_hid *ihid = i2c_get_clientdata(client);
 617         size_t ret_count, ask_count;
 618         int ret;
 619
 620         if (report_type == HID_OUTPUT_REPORT)
 621                 return -EINVAL;
 622
 623         /*
 624          * In case of unnumbered reports the response from the device will
 625          * not have the report ID that the upper layers expect, so we need
 626          * to stash it the buffer ourselves and adjust the data size.
 627          */
 628         if (!report_number) {
 629                 buf[0] = 0;
 630                 buf++;
 631                 count--;
 632         }
 633
 634         /* +2 bytes to include the size of the reply in the query buffer */
 635         ask_count = min(count + 2, (size_t)ihid->bufsize);
 636
 637         ret = i2c_hid_get_report(client,
 638                         report_type == HID_FEATURE_REPORT ? 0x03 : 0x01,
 639                         report_number, ihid->rawbuf, ask_count);
 640
 641         if (ret < 0)
 642                 return ret;
 643
 644         ret_count = ihid->rawbuf[0] | (ihid->rawbuf[1] << 8);
 645
 646         if (ret_count <= 2)
 647                 return 0;
 648
 649         ret_count = min(ret_count, ask_count);
 650
 651         /* The query buffer contains the size, dropping it in the reply */
 652         count = min(count, ret_count - 2);
 653         memcpy(buf, ihid->rawbuf + 2, count);
 654
 655         if (!report_number)
 656                 count++;
 657
 658         return count;
 659 }
 660
 661 static int i2c_hid_output_raw_report(struct hid_device *hid, __u8 *buf,
 662                 size_t count, unsigned char report_type, bool use_data)
 663 {
 664         struct i2c_client *client = hid->driver_data;
 665         struct i2c_hid *ihid = i2c_get_clientdata(client);
 666         int report_id = buf[0];
 667         int ret;
 668
 669         if (report_type == HID_INPUT_REPORT)
 670                 return -EINVAL;
 671
 672         mutex_lock(&ihid->reset_lock);
 673
 674         /*
 675          * Note that both numbered and unnumbered reports passed here
 676          * are supposed to have report ID stored in the 1st byte of the
 677          * buffer, so we strip it off unconditionally before passing payload
 678          * to i2c_hid_set_or_send_report which takes care of encoding
 679          * everything properly.
 680          */
 681         ret = i2c_hid_set_or_send_report(client,
 682                                 report_type == HID_FEATURE_REPORT ? 0x03 : 0x02,
 683                                 report_id, buf + 1, count - 1, use_data);
 684
 685         if (ret >= 0)
 686                 ret++; /* add report_id to the number of transferred bytes */
 687
 688         mutex_unlock(&ihid->reset_lock);
 689
 690         return ret;
 691 }
 692
 693 static int i2c_hid_output_report(struct hid_device *hid, __u8 *buf,
 694                 size_t count)
 695 {
 696         return i2c_hid_output_raw_report(hid, buf, count, HID_OUTPUT_REPORT,
 697                         false);
 698 }
 699
 700 static int i2c_hid_raw_request(struct hid_device *hid, unsigned char reportnum,
 701                                __u8 *buf, size_t len, unsigned char rtype,
 702                                int reqtype)
 703 {
 704         switch (reqtype) {
 705         case HID_REQ_GET_REPORT:
 706                 return i2c_hid_get_raw_report(hid, reportnum, buf, len, rtype);
 707         case HID_REQ_SET_REPORT:
 708                 if (buf[0] != reportnum)
 709                         return -EINVAL;
 710                 return i2c_hid_output_raw_report(hid, buf, len, rtype, true);
 711         default:
 712                 return -EIO;
 713         }
 714 }
 715
 716 static int i2c_hid_parse(struct hid_device *hid)
 717 {
 718         struct i2c_client *client = hid->driver_data;
 719         struct i2c_hid *ihid = i2c_get_clientdata(client);
 720         struct i2c_hid_desc *hdesc = &ihid->hdesc;
 721         unsigned int rsize;
 722         char *rdesc;
 723         int ret;
 724         int tries = 3;
 725         char *use_override;
 726
 727         i2c_hid_dbg(ihid, "entering %s\n", __func__);
 728
 729         rsize = le16_to_cpu(hdesc->wReportDescLength);
 730         if (!rsize || rsize > HID_MAX_DESCRIPTOR_SIZE) {
 731                 dbg_hid("weird size of report descriptor (%u)\n", rsize);
 732                 return -EINVAL;
 733         }
 734
 735         do {
 736                 ret = i2c_hid_hwreset(client);
 737                 if (ret)
 738                         msleep(1000);
 739         } while (tries-- > 0 && ret);
 740
 741         if (ret)
 742                 return ret;
 743
 744         use_override = i2c_hid_get_dmi_hid_report_desc_override(client->name,
 745                                                                 &rsize);
 746
 747         if (use_override) {
 748                 rdesc = use_override;
 749                 i2c_hid_dbg(ihid, "Using a HID report descriptor override\n");
 750         } else {
 751                 rdesc = kzalloc(rsize, GFP_KERNEL);
 752
 753                 if (!rdesc) {
 754                         dbg_hid("couldn't allocate rdesc memory\n");
 755                         return -ENOMEM;
 756                 }
 757
 758                 i2c_hid_dbg(ihid, "asking HID report descriptor\n");
 759
 760                 ret = i2c_hid_command(client, &hid_report_descr_cmd,
 761                                       rdesc, rsize);
 762                 if (ret) {
 763                         hid_err(hid, "reading report descriptor failed\n");
 764                         kfree(rdesc);
 765                         return -EIO;
 766                 }
 767         }
 768
 769         i2c_hid_dbg(ihid, "Report Descriptor: %*ph\n", rsize, rdesc);
 770
 771         ret = hid_parse_report(hid, rdesc, rsize);
 772         if (!use_override)
 773                 kfree(rdesc);
 774
 775         if (ret) {
 776                 dbg_hid("parsing report descriptor failed\n");
 777                 return ret;
 778         }
 779
 780         return 0;
 781 }
 782
 783 static int i2c_hid_start(struct hid_device *hid)
 784 {
 785         struct i2c_client *client = hid->driver_data;
 786         struct i2c_hid *ihid = i2c_get_clientdata(client);
 787         int ret;
 788         unsigned int bufsize = HID_MIN_BUFFER_SIZE;
 789
 790         i2c_hid_find_max_report(hid, HID_INPUT_REPORT, &bufsize);
 791         i2c_hid_find_max_report(hid, HID_OUTPUT_REPORT, &bufsize);
 792         i2c_hid_find_max_report(hid, HID_FEATURE_REPORT, &bufsize);
 793
 794         if (bufsize > ihid->bufsize) {
 795                 disable_irq(client->irq);
 796                 i2c_hid_free_buffers(ihid);
 797
 798                 ret = i2c_hid_alloc_buffers(ihid, bufsize);
 799                 enable_irq(client->irq);
 800
 801                 if (ret)
 802                         return ret;
 803         }
 804
 805         return 0;
 806 }
 807
 808 static void i2c_hid_stop(struct hid_device *hid)
 809 {
 810         hid->claimed = 0;
 811 }
 812
 813 static int i2c_hid_open(struct hid_device *hid)
 814 {
 815         struct i2c_client *client = hid->driver_data;
 816         struct i2c_hid *ihid = i2c_get_clientdata(client);
 817
 818         set_bit(I2C_HID_STARTED, &ihid->flags);
 819         return 0;
 820 }
 821
 822 static void i2c_hid_close(struct hid_device *hid)
 823 {
 824         struct i2c_client *client = hid->driver_data;
 825         struct i2c_hid *ihid = i2c_get_clientdata(client);
 826
 827         clear_bit(I2C_HID_STARTED, &ihid->flags);
 828 }
 829
 830 struct hid_ll_driver i2c_hid_ll_driver = {
 831         .parse = i2c_hid_parse,
 832         .start = i2c_hid_start,
 833         .stop = i2c_hid_stop,
 834         .open = i2c_hid_open,
 835         .close = i2c_hid_close,
 836         .output_report = i2c_hid_output_report,
 837         .raw_request = i2c_hid_raw_request,
 838 };
 839 EXPORT_SYMBOL_GPL(i2c_hid_ll_driver);
 840
 841 static int i2c_hid_init_irq(struct i2c_client *client)
 842 {
 843         struct i2c_hid *ihid = i2c_get_clientdata(client);
 844         unsigned long irqflags = 0;
 845         int ret;
 846
 847         dev_dbg(&client->dev, "Requesting IRQ: %d\n", client->irq);
 848
 849         if (!irq_get_trigger_type(client->irq))
 850                 irqflags = IRQF_TRIGGER_LOW;
 851
 852         ret = request_threaded_irq(client->irq, NULL, i2c_hid_irq,
 853                                    irqflags | IRQF_ONESHOT, client->name, ihid);
 854         if (ret < 0) {
 855                 dev_warn(&client->dev,
 856                         "Could not register for %s interrupt, irq = %d,"
 857                         " ret = %d\n",
 858                         client->name, client->irq, ret);
 859
 860                 return ret;
 861         }
 862
 863         return 0;
 864 }
 865
 866 static int i2c_hid_fetch_hid_descriptor(struct i2c_hid *ihid)
 867 {
 868         struct i2c_client *client = ihid->client;
 869         struct i2c_hid_desc *hdesc = &ihid->hdesc;
 870         unsigned int dsize;
 871         int ret;
 872
 873         /* i2c hid fetch using a fixed descriptor size (30 bytes) */
 874         if (i2c_hid_get_dmi_i2c_hid_desc_override(client->name)) {
 875                 i2c_hid_dbg(ihid, "Using a HID descriptor override\n");
 876                 ihid->hdesc =
 877                         *i2c_hid_get_dmi_i2c_hid_desc_override(client->name);
 878         } else {
 879                 i2c_hid_dbg(ihid, "Fetching the HID descriptor\n");
 880                 ret = i2c_hid_command(client, &hid_descr_cmd,
 881                                       ihid->hdesc_buffer,
 882                                       sizeof(struct i2c_hid_desc));
 883                 if (ret) {
 884                         dev_err(&client->dev, "hid_descr_cmd failed\n");
 885                         return -ENODEV;
 886                 }
 887         }
 888
 889         /* Validate the length of HID descriptor, the 4 first bytes:
 890          * bytes 0-1 -> length
 891          * bytes 2-3 -> bcdVersion (has to be 1.00) */
 892         /* check bcdVersion == 1.0 */
 893         if (le16_to_cpu(hdesc->bcdVersion) != 0x0100) {
 894                 dev_err(&client->dev,
 895                         "unexpected HID descriptor bcdVersion (0x%04hx)\n",
 896                         le16_to_cpu(hdesc->bcdVersion));
 897                 return -ENODEV;
 898         }
 899
 900         /* Descriptor length should be 30 bytes as per the specification */
 901         dsize = le16_to_cpu(hdesc->wHIDDescLength);
 902         if (dsize != sizeof(struct i2c_hid_desc)) {
 903                 dev_err(&client->dev, "weird size of HID descriptor (%u)\n",
 904                         dsize);
 905                 return -ENODEV;
 906         }
 907         i2c_hid_dbg(ihid, "HID Descriptor: %*ph\n", dsize, ihid->hdesc_buffer);
 908         return 0;
 909 }
 910
 911 #ifdef CONFIG_ACPI
 912 static const struct acpi_device_id i2c_hid_acpi_blacklist[] = {
 913         /*
 914          * The CHPN0001 ACPI device, which is used to describe the Chipone
 915          * ICN8505 controller, has a _CID of PNP0C50 but is not HID compatible.
 916          */
 917         {"CHPN0001", 0 },
 918         { },
 919 };
 920
 921 static int i2c_hid_acpi_pdata(struct i2c_client *client,
 922                 struct i2c_hid_platform_data *pdata)
 923 {
 924         static guid_t i2c_hid_guid =
 925                 GUID_INIT(0x3CDFF6F7, 0x4267, 0x4555,
 926                           0xAD, 0x05, 0xB3, 0x0A, 0x3D, 0x89, 0x38, 0xDE);
 927         union acpi_object *obj;
 928         struct acpi_device *adev;
 929         acpi_handle handle;
 930
 931         handle = ACPI_HANDLE(&client->dev);
 932         if (!handle || acpi_bus_get_device(handle, &adev)) {
 933                 dev_err(&client->dev, "Error could not get ACPI device\n");
 934                 return -ENODEV;
 935         }
 936
 937         if (acpi_match_device_ids(adev, i2c_hid_acpi_blacklist) == 0)
 938                 return -ENODEV;
 939
 940         obj = acpi_evaluate_dsm_typed(handle, &i2c_hid_guid, 1, 1, NULL,
 941                                       ACPI_TYPE_INTEGER);
 942         if (!obj) {
 943                 dev_err(&client->dev, "Error _DSM call to get HID descriptor address failed\n");
 944                 return -ENODEV;
 945         }
 946
 947         pdata->hid_descriptor_address = obj->integer.value;
 948         ACPI_FREE(obj);
 949
 950         return 0;
 951 }
 952
 953 static void i2c_hid_acpi_fix_up_power(struct device *dev)
 954 {
 955         struct acpi_device *adev;
 956
 957         adev = ACPI_COMPANION(dev);
 958         if (adev)
 959                 acpi_device_fix_up_power(adev);
 960 }
 961
 962 static void i2c_hid_acpi_enable_wakeup(struct device *dev)
 963 {
 964         if (acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0) {
 965                 device_set_wakeup_capable(dev, true);
 966                 device_set_wakeup_enable(dev, false);
 967         }
 968 }
 969
 970 static void i2c_hid_acpi_shutdown(struct device *dev)
 971 {
 972         acpi_device_set_power(ACPI_COMPANION(dev), ACPI_STATE_D3_COLD);
 973 }
 974
 975 static const struct acpi_device_id i2c_hid_acpi_match[] = {
 976         {"ACPI0C50", 0 },
 977         {"PNP0C50", 0 },
 978         { },
 979 };
 980 MODULE_DEVICE_TABLE(acpi, i2c_hid_acpi_match);
 981 #else
 982 static inline int i2c_hid_acpi_pdata(struct i2c_client *client,
 983                 struct i2c_hid_platform_data *pdata)
 984 {
 985         return -ENODEV;
 986 }
 987
 988 static inline void i2c_hid_acpi_fix_up_power(struct device *dev) {}
 989
 990 static inline void i2c_hid_acpi_enable_wakeup(struct device *dev) {}
 991
 992 static inline void i2c_hid_acpi_shutdown(struct device *dev) {}
 993 #endif
 994
 995 #ifdef CONFIG_OF
 996 static int i2c_hid_of_probe(struct i2c_client *client,
 997                 struct i2c_hid_platform_data *pdata)
 998 {
 999         struct device *dev = &client->dev;
1000         u32 val;
1001         int ret;
1002
1003         ret = of_property_read_u32(dev->of_node, "hid-descr-addr", &val);
1004         if (ret) {
1005                 dev_err(&client->dev, "HID register address not provided\n");
1006                 return -ENODEV;
1007         }
1008         if (val >> 16) {
1009                 dev_err(&client->dev, "Bad HID register address: 0x%08x\n",
1010                         val);
1011                 return -EINVAL;
1012         }
1013         pdata->hid_descriptor_address = val;
1014
1015         return 0;
1016 }
1017
1018 static const struct of_device_id i2c_hid_of_match[] = {
1019         { .compatible = "hid-over-i2c" },
1020         {},
1021 };
1022 MODULE_DEVICE_TABLE(of, i2c_hid_of_match);
1023 #else
1024 static inline int i2c_hid_of_probe(struct i2c_client *client,
1025                 struct i2c_hid_platform_data *pdata)
1026 {
1027         return -ENODEV;
1028 }
1029 #endif
1030
1031 static void i2c_hid_fwnode_probe(struct i2c_client *client,
1032                                  struct i2c_hid_platform_data *pdata)
1033 {
1034         u32 val;
1035
1036         if (!device_property_read_u32(&client->dev, "post-power-on-delay-ms",
1037                                       &val))
1038                 pdata->post_power_delay_ms = val;
1039 }
1040
1041 static int i2c_hid_probe(struct i2c_client *client,
1042                          const struct i2c_device_id *dev_id)
1043 {
1044         int ret;
1045         struct i2c_hid *ihid;
1046         struct hid_device *hid;
1047         __u16 hidRegister;
1048         struct i2c_hid_platform_data *platform_data = client->dev.platform_data;
1049
1050         dbg_hid("HID probe called for i2c 0x%02x\n", client->addr);
1051
1052         if (!client->irq) {
1053                 dev_err(&client->dev,
1054                         "HID over i2c has not been provided an Int IRQ\n");
1055                 return -EINVAL;
1056         }
1057
1058         if (client->irq < 0) {
1059                 if (client->irq != -EPROBE_DEFER)
1060                         dev_err(&client->dev,
1061                                 "HID over i2c doesn't have a valid IRQ\n");
1062                 return client->irq;
1063         }
1064
1065         ihid = devm_kzalloc(&client->dev, sizeof(*ihid), GFP_KERNEL);
1066         if (!ihid)
1067                 return -ENOMEM;
1068
1069         if (client->dev.of_node) {
1070                 ret = i2c_hid_of_probe(client, &ihid->pdata);
1071                 if (ret)
1072                         return ret;
1073         } else if (!platform_data) {
1074                 ret = i2c_hid_acpi_pdata(client, &ihid->pdata);
1075                 if (ret)
1076                         return ret;
1077         } else {
1078                 ihid->pdata = *platform_data;
1079         }
1080
1081         /* Parse platform agnostic common properties from ACPI / device tree */
1082         i2c_hid_fwnode_probe(client, &ihid->pdata);
1083
1084         ihid->pdata.supplies[0].supply = "vdd";
1085         ihid->pdata.supplies[1].supply = "vddl";
1086
1087         ret = devm_regulator_bulk_get(&client->dev,
1088                                       ARRAY_SIZE(ihid->pdata.supplies),
1089                                       ihid->pdata.supplies);
1090         if (ret)
1091                 return ret;
1092
1093         ret = regulator_bulk_enable(ARRAY_SIZE(ihid->pdata.supplies),
1094                                     ihid->pdata.supplies);
1095         if (ret < 0)
1096                 return ret;
1097
1098         if (ihid->pdata.post_power_delay_ms)
1099                 msleep(ihid->pdata.post_power_delay_ms);
1100
1101         i2c_set_clientdata(client, ihid);
1102
1103         ihid->client = client;
1104
1105         hidRegister = ihid->pdata.hid_descriptor_address;
1106         ihid->wHIDDescRegister = cpu_to_le16(hidRegister);
1107
1108         init_waitqueue_head(&ihid->wait);
1109         mutex_init(&ihid->reset_lock);
1110
1111         /* we need to allocate the command buffer without knowing the maximum
1112          * size of the reports. Let's use HID_MIN_BUFFER_SIZE, then we do the
1113          * real computation later. */
1114         ret = i2c_hid_alloc_buffers(ihid, HID_MIN_BUFFER_SIZE);
1115         if (ret < 0)
1116                 goto err_regulator;
1117
1118         i2c_hid_acpi_fix_up_power(&client->dev);
1119
1120         i2c_hid_acpi_enable_wakeup(&client->dev);
1121
1122         device_enable_async_suspend(&client->dev);
1123
1124         /* Make sure there is something at this address */
1125         ret = i2c_smbus_read_byte(client);
1126         if (ret < 0) {
1127                 dev_dbg(&client->dev, "nothing at this address: %d\n", ret);
1128                 ret = -ENXIO;
1129                 goto err_regulator;
1130         }
1131
1132         ret = i2c_hid_fetch_hid_descriptor(ihid);
1133         if (ret < 0)
1134                 goto err_regulator;
1135
1136         ret = i2c_hid_init_irq(client);
1137         if (ret < 0)
1138                 goto err_regulator;
1139
1140         hid = hid_allocate_device();
1141         if (IS_ERR(hid)) {
1142                 ret = PTR_ERR(hid);
1143                 goto err_irq;
1144         }
1145
1146         ihid->hid = hid;
1147
1148         hid->driver_data = client;
1149         hid->ll_driver = &i2c_hid_ll_driver;
1150         hid->dev.parent = &client->dev;
1151         hid->bus = BUS_I2C;
1152         hid->version = le16_to_cpu(ihid->hdesc.bcdVersion);
1153         hid->vendor = le16_to_cpu(ihid->hdesc.wVendorID);
1154         hid->product = le16_to_cpu(ihid->hdesc.wProductID);
1155
1156         snprintf(hid->name, sizeof(hid->name), "%s %04X:%04X",
1157                  client->name, (u16)hid->vendor, (u16)hid->product);
1158         strlcpy(hid->phys, dev_name(&client->dev), sizeof(hid->phys));
1159
1160         ihid->quirks = i2c_hid_lookup_quirk(hid->vendor, hid->product);
1161
1162         ret = hid_add_device(hid);
1163         if (ret) {
1164                 if (ret != -ENODEV)
1165                         hid_err(client, "can't add hid device: %d\n", ret);
1166                 goto err_mem_free;
1167         }
1168
1169         return 0;
1170
1171 err_mem_free:
1172         hid_destroy_device(hid);
1173
1174 err_irq:
1175         free_irq(client->irq, ihid);
1176
1177 err_regulator:
1178         regulator_bulk_disable(ARRAY_SIZE(ihid->pdata.supplies),
1179                                ihid->pdata.supplies);
1180         i2c_hid_free_buffers(ihid);
1181         return ret;
1182 }
1183
1184 static int i2c_hid_remove(struct i2c_client *client)
1185 {
1186         struct i2c_hid *ihid = i2c_get_clientdata(client);
1187         struct hid_device *hid;
1188
1189         hid = ihid->hid;
1190         hid_destroy_device(hid);
1191
1192         free_irq(client->irq, ihid);
1193
1194         if (ihid->bufsize)
1195                 i2c_hid_free_buffers(ihid);
1196
1197         regulator_bulk_disable(ARRAY_SIZE(ihid->pdata.supplies),
1198                                ihid->pdata.supplies);
1199
1200         return 0;
1201 }
1202
1203 static void i2c_hid_shutdown(struct i2c_client *client)
1204 {
1205         struct i2c_hid *ihid = i2c_get_clientdata(client);
1206
1207         i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
1208         free_irq(client->irq, ihid);
1209
1210         i2c_hid_acpi_shutdown(&client->dev);
1211 }
1212
1213 #ifdef CONFIG_PM_SLEEP
1214 static int i2c_hid_suspend(struct device *dev)
1215 {
1216         struct i2c_client *client = to_i2c_client(dev);
1217         struct i2c_hid *ihid = i2c_get_clientdata(client);
1218         struct hid_device *hid = ihid->hid;
1219         int ret;
1220         int wake_status;
1221
1222         if (hid->driver && hid->driver->suspend) {
1223                 ret = hid->driver->suspend(hid, PMSG_SUSPEND);
1224                 if (ret < 0)
1225                         return ret;
1226         }
1227
1228         /* Save some power */
1229         i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
1230
1231         disable_irq(client->irq);
1232
1233         if (device_may_wakeup(&client->dev)) {
1234                 wake_status = enable_irq_wake(client->irq);
1235                 if (!wake_status)
1236                         ihid->irq_wake_enabled = true;
1237                 else
1238                         hid_warn(hid, "Failed to enable irq wake: %d\n",
1239                                 wake_status);
1240         } else {
1241                 regulator_bulk_disable(ARRAY_SIZE(ihid->pdata.supplies),
1242                                        ihid->pdata.supplies);
1243         }
1244
1245         return 0;
1246 }
1247
1248 static int i2c_hid_resume(struct device *dev)
1249 {
1250         int ret;
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 wake_status;
1255
1256         if (!device_may_wakeup(&client->dev)) {
1257                 ret = regulator_bulk_enable(ARRAY_SIZE(ihid->pdata.supplies),
1258                                             ihid->pdata.supplies);
1259                 if (ret)
1260                         hid_warn(hid, "Failed to enable supplies: %d\n", ret);
1261
1262                 if (ihid->pdata.post_power_delay_ms)
1263                         msleep(ihid->pdata.post_power_delay_ms);
1264         } else if (ihid->irq_wake_enabled) {
1265                 wake_status = disable_irq_wake(client->irq);
1266                 if (!wake_status)
1267                         ihid->irq_wake_enabled = false;
1268                 else
1269                         hid_warn(hid, "Failed to disable irq wake: %d\n",
1270                                 wake_status);
1271         }
1272
1273         enable_irq(client->irq);
1274
1275         /* Instead of resetting device, simply powers the device on. This
1276          * solves "incomplete reports" on Raydium devices 2386:3118 and
1277          * 2386:4B33 and fixes various SIS touchscreens no longer sending
1278          * data after a suspend/resume.
1279          *
1280          * However some ALPS touchpads generate IRQ storm without reset, so
1281          * let's still reset them here.
1282          */
1283         if (ihid->quirks & I2C_HID_QUIRK_RESET_ON_RESUME)
1284                 ret = i2c_hid_hwreset(client);
1285         else
1286                 ret = i2c_hid_set_power(client, I2C_HID_PWR_ON);
1287
1288         if (ret)
1289                 return ret;
1290
1291         if (hid->driver && hid->driver->reset_resume) {
1292                 ret = hid->driver->reset_resume(hid);
1293                 return ret;
1294         }
1295
1296         return 0;
1297 }
1298 #endif
1299
1300 static const struct dev_pm_ops i2c_hid_pm = {
1301         SET_SYSTEM_SLEEP_PM_OPS(i2c_hid_suspend, i2c_hid_resume)
1302 };
1303
1304 static const struct i2c_device_id i2c_hid_id_table[] = {
1305         { "hid", 0 },
1306         { "hid-over-i2c", 0 },
1307         { },
1308 };
1309 MODULE_DEVICE_TABLE(i2c, i2c_hid_id_table);
1310
1311
1312 static struct i2c_driver i2c_hid_driver = {
1313         .driver = {
1314                 .name   = "i2c_hid",
1315                 .pm     = &i2c_hid_pm,
1316                 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
1317                 .acpi_match_table = ACPI_PTR(i2c_hid_acpi_match),
1318                 .of_match_table = of_match_ptr(i2c_hid_of_match),
1319         },
1320
1321         .probe          = i2c_hid_probe,
1322         .remove         = i2c_hid_remove,
1323         .shutdown       = i2c_hid_shutdown,
1324         .id_table       = i2c_hid_id_table,
1325 };
1326
1327 module_i2c_driver(i2c_hid_driver);
1328
1329 MODULE_DESCRIPTION("HID over I2C core driver");
1330 MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
1331 MODULE_LICENSE("GPL");