linux/drivers/input/misc/ims-pcu.c
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   1/*
   2 * Driver for IMS Passenger Control Unit Devices
   3 *
   4 * Copyright (C) 2013 The IMS Company
   5 *
   6 * This program is free software; you can redistribute it and/or modify
   7 * it under the terms of the GNU General Public License version 2
   8 * as published by the Free Software Foundation.
   9 */
  10
  11#include <linux/completion.h>
  12#include <linux/device.h>
  13#include <linux/firmware.h>
  14#include <linux/ihex.h>
  15#include <linux/input.h>
  16#include <linux/kernel.h>
  17#include <linux/leds.h>
  18#include <linux/module.h>
  19#include <linux/slab.h>
  20#include <linux/types.h>
  21#include <linux/usb/input.h>
  22#include <linux/usb/cdc.h>
  23#include <asm/unaligned.h>
  24
  25#define IMS_PCU_KEYMAP_LEN              32
  26
  27struct ims_pcu_buttons {
  28        struct input_dev *input;
  29        char name[32];
  30        char phys[32];
  31        unsigned short keymap[IMS_PCU_KEYMAP_LEN];
  32};
  33
  34struct ims_pcu_gamepad {
  35        struct input_dev *input;
  36        char name[32];
  37        char phys[32];
  38};
  39
  40struct ims_pcu_backlight {
  41        struct led_classdev cdev;
  42        struct work_struct work;
  43        enum led_brightness desired_brightness;
  44        char name[32];
  45};
  46
  47#define IMS_PCU_PART_NUMBER_LEN         15
  48#define IMS_PCU_SERIAL_NUMBER_LEN       8
  49#define IMS_PCU_DOM_LEN                 8
  50#define IMS_PCU_FW_VERSION_LEN          (9 + 1)
  51#define IMS_PCU_BL_VERSION_LEN          (9 + 1)
  52#define IMS_PCU_BL_RESET_REASON_LEN     (2 + 1)
  53
  54#define IMS_PCU_PCU_B_DEVICE_ID         5
  55
  56#define IMS_PCU_BUF_SIZE                128
  57
  58struct ims_pcu {
  59        struct usb_device *udev;
  60        struct device *dev; /* control interface's device, used for logging */
  61
  62        unsigned int device_no;
  63
  64        bool bootloader_mode;
  65
  66        char part_number[IMS_PCU_PART_NUMBER_LEN];
  67        char serial_number[IMS_PCU_SERIAL_NUMBER_LEN];
  68        char date_of_manufacturing[IMS_PCU_DOM_LEN];
  69        char fw_version[IMS_PCU_FW_VERSION_LEN];
  70        char bl_version[IMS_PCU_BL_VERSION_LEN];
  71        char reset_reason[IMS_PCU_BL_RESET_REASON_LEN];
  72        int update_firmware_status;
  73        u8 device_id;
  74
  75        u8 ofn_reg_addr;
  76
  77        struct usb_interface *ctrl_intf;
  78
  79        struct usb_endpoint_descriptor *ep_ctrl;
  80        struct urb *urb_ctrl;
  81        u8 *urb_ctrl_buf;
  82        dma_addr_t ctrl_dma;
  83        size_t max_ctrl_size;
  84
  85        struct usb_interface *data_intf;
  86
  87        struct usb_endpoint_descriptor *ep_in;
  88        struct urb *urb_in;
  89        u8 *urb_in_buf;
  90        dma_addr_t read_dma;
  91        size_t max_in_size;
  92
  93        struct usb_endpoint_descriptor *ep_out;
  94        u8 *urb_out_buf;
  95        size_t max_out_size;
  96
  97        u8 read_buf[IMS_PCU_BUF_SIZE];
  98        u8 read_pos;
  99        u8 check_sum;
 100        bool have_stx;
 101        bool have_dle;
 102
 103        u8 cmd_buf[IMS_PCU_BUF_SIZE];
 104        u8 ack_id;
 105        u8 expected_response;
 106        u8 cmd_buf_len;
 107        struct completion cmd_done;
 108        struct mutex cmd_mutex;
 109
 110        u32 fw_start_addr;
 111        u32 fw_end_addr;
 112        struct completion async_firmware_done;
 113
 114        struct ims_pcu_buttons buttons;
 115        struct ims_pcu_gamepad *gamepad;
 116        struct ims_pcu_backlight backlight;
 117
 118        bool setup_complete; /* Input and LED devices have been created */
 119};
 120
 121
 122/*********************************************************************
 123 *             Buttons Input device support                          *
 124 *********************************************************************/
 125
 126static const unsigned short ims_pcu_keymap_1[] = {
 127        [1] = KEY_ATTENDANT_OFF,
 128        [2] = KEY_ATTENDANT_ON,
 129        [3] = KEY_LIGHTS_TOGGLE,
 130        [4] = KEY_VOLUMEUP,
 131        [5] = KEY_VOLUMEDOWN,
 132        [6] = KEY_INFO,
 133};
 134
 135static const unsigned short ims_pcu_keymap_2[] = {
 136        [4] = KEY_VOLUMEUP,
 137        [5] = KEY_VOLUMEDOWN,
 138        [6] = KEY_INFO,
 139};
 140
 141static const unsigned short ims_pcu_keymap_3[] = {
 142        [1] = KEY_HOMEPAGE,
 143        [2] = KEY_ATTENDANT_TOGGLE,
 144        [3] = KEY_LIGHTS_TOGGLE,
 145        [4] = KEY_VOLUMEUP,
 146        [5] = KEY_VOLUMEDOWN,
 147        [6] = KEY_DISPLAYTOGGLE,
 148        [18] = KEY_PLAYPAUSE,
 149};
 150
 151static const unsigned short ims_pcu_keymap_4[] = {
 152        [1] = KEY_ATTENDANT_OFF,
 153        [2] = KEY_ATTENDANT_ON,
 154        [3] = KEY_LIGHTS_TOGGLE,
 155        [4] = KEY_VOLUMEUP,
 156        [5] = KEY_VOLUMEDOWN,
 157        [6] = KEY_INFO,
 158        [18] = KEY_PLAYPAUSE,
 159};
 160
 161static const unsigned short ims_pcu_keymap_5[] = {
 162        [1] = KEY_ATTENDANT_OFF,
 163        [2] = KEY_ATTENDANT_ON,
 164        [3] = KEY_LIGHTS_TOGGLE,
 165};
 166
 167struct ims_pcu_device_info {
 168        const unsigned short *keymap;
 169        size_t keymap_len;
 170        bool has_gamepad;
 171};
 172
 173#define IMS_PCU_DEVINFO(_n, _gamepad)                           \
 174        [_n] = {                                                \
 175                .keymap = ims_pcu_keymap_##_n,                  \
 176                .keymap_len = ARRAY_SIZE(ims_pcu_keymap_##_n),  \
 177                .has_gamepad = _gamepad,                        \
 178        }
 179
 180static const struct ims_pcu_device_info ims_pcu_device_info[] = {
 181        IMS_PCU_DEVINFO(1, true),
 182        IMS_PCU_DEVINFO(2, true),
 183        IMS_PCU_DEVINFO(3, true),
 184        IMS_PCU_DEVINFO(4, true),
 185        IMS_PCU_DEVINFO(5, false),
 186};
 187
 188static void ims_pcu_buttons_report(struct ims_pcu *pcu, u32 data)
 189{
 190        struct ims_pcu_buttons *buttons = &pcu->buttons;
 191        struct input_dev *input = buttons->input;
 192        int i;
 193
 194        for (i = 0; i < 32; i++) {
 195                unsigned short keycode = buttons->keymap[i];
 196
 197                if (keycode != KEY_RESERVED)
 198                        input_report_key(input, keycode, data & (1UL << i));
 199        }
 200
 201        input_sync(input);
 202}
 203
 204static int ims_pcu_setup_buttons(struct ims_pcu *pcu,
 205                                 const unsigned short *keymap,
 206                                 size_t keymap_len)
 207{
 208        struct ims_pcu_buttons *buttons = &pcu->buttons;
 209        struct input_dev *input;
 210        int i;
 211        int error;
 212
 213        input = input_allocate_device();
 214        if (!input) {
 215                dev_err(pcu->dev,
 216                        "Not enough memory for input input device\n");
 217                return -ENOMEM;
 218        }
 219
 220        snprintf(buttons->name, sizeof(buttons->name),
 221                 "IMS PCU#%d Button Interface", pcu->device_no);
 222
 223        usb_make_path(pcu->udev, buttons->phys, sizeof(buttons->phys));
 224        strlcat(buttons->phys, "/input0", sizeof(buttons->phys));
 225
 226        memcpy(buttons->keymap, keymap, sizeof(*keymap) * keymap_len);
 227
 228        input->name = buttons->name;
 229        input->phys = buttons->phys;
 230        usb_to_input_id(pcu->udev, &input->id);
 231        input->dev.parent = &pcu->ctrl_intf->dev;
 232
 233        input->keycode = buttons->keymap;
 234        input->keycodemax = ARRAY_SIZE(buttons->keymap);
 235        input->keycodesize = sizeof(buttons->keymap[0]);
 236
 237        __set_bit(EV_KEY, input->evbit);
 238        for (i = 0; i < IMS_PCU_KEYMAP_LEN; i++)
 239                __set_bit(buttons->keymap[i], input->keybit);
 240        __clear_bit(KEY_RESERVED, input->keybit);
 241
 242        error = input_register_device(input);
 243        if (error) {
 244                dev_err(pcu->dev,
 245                        "Failed to register buttons input device: %d\n",
 246                        error);
 247                input_free_device(input);
 248                return error;
 249        }
 250
 251        buttons->input = input;
 252        return 0;
 253}
 254
 255static void ims_pcu_destroy_buttons(struct ims_pcu *pcu)
 256{
 257        struct ims_pcu_buttons *buttons = &pcu->buttons;
 258
 259        input_unregister_device(buttons->input);
 260}
 261
 262
 263/*********************************************************************
 264 *             Gamepad Input device support                          *
 265 *********************************************************************/
 266
 267static void ims_pcu_gamepad_report(struct ims_pcu *pcu, u32 data)
 268{
 269        struct ims_pcu_gamepad *gamepad = pcu->gamepad;
 270        struct input_dev *input = gamepad->input;
 271        int x, y;
 272
 273        x = !!(data & (1 << 14)) - !!(data & (1 << 13));
 274        y = !!(data & (1 << 12)) - !!(data & (1 << 11));
 275
 276        input_report_abs(input, ABS_X, x);
 277        input_report_abs(input, ABS_Y, y);
 278
 279        input_report_key(input, BTN_A, data & (1 << 7));
 280        input_report_key(input, BTN_B, data & (1 << 8));
 281        input_report_key(input, BTN_X, data & (1 << 9));
 282        input_report_key(input, BTN_Y, data & (1 << 10));
 283        input_report_key(input, BTN_START, data & (1 << 15));
 284        input_report_key(input, BTN_SELECT, data & (1 << 16));
 285
 286        input_sync(input);
 287}
 288
 289static int ims_pcu_setup_gamepad(struct ims_pcu *pcu)
 290{
 291        struct ims_pcu_gamepad *gamepad;
 292        struct input_dev *input;
 293        int error;
 294
 295        gamepad = kzalloc(sizeof(struct ims_pcu_gamepad), GFP_KERNEL);
 296        input = input_allocate_device();
 297        if (!gamepad || !input) {
 298                dev_err(pcu->dev,
 299                        "Not enough memory for gamepad device\n");
 300                error = -ENOMEM;
 301                goto err_free_mem;
 302        }
 303
 304        gamepad->input = input;
 305
 306        snprintf(gamepad->name, sizeof(gamepad->name),
 307                 "IMS PCU#%d Gamepad Interface", pcu->device_no);
 308
 309        usb_make_path(pcu->udev, gamepad->phys, sizeof(gamepad->phys));
 310        strlcat(gamepad->phys, "/input1", sizeof(gamepad->phys));
 311
 312        input->name = gamepad->name;
 313        input->phys = gamepad->phys;
 314        usb_to_input_id(pcu->udev, &input->id);
 315        input->dev.parent = &pcu->ctrl_intf->dev;
 316
 317        __set_bit(EV_KEY, input->evbit);
 318        __set_bit(BTN_A, input->keybit);
 319        __set_bit(BTN_B, input->keybit);
 320        __set_bit(BTN_X, input->keybit);
 321        __set_bit(BTN_Y, input->keybit);
 322        __set_bit(BTN_START, input->keybit);
 323        __set_bit(BTN_SELECT, input->keybit);
 324
 325        __set_bit(EV_ABS, input->evbit);
 326        input_set_abs_params(input, ABS_X, -1, 1, 0, 0);
 327        input_set_abs_params(input, ABS_Y, -1, 1, 0, 0);
 328
 329        error = input_register_device(input);
 330        if (error) {
 331                dev_err(pcu->dev,
 332                        "Failed to register gamepad input device: %d\n",
 333                        error);
 334                goto err_free_mem;
 335        }
 336
 337        pcu->gamepad = gamepad;
 338        return 0;
 339
 340err_free_mem:
 341        input_free_device(input);
 342        kfree(gamepad);
 343        return -ENOMEM;
 344}
 345
 346static void ims_pcu_destroy_gamepad(struct ims_pcu *pcu)
 347{
 348        struct ims_pcu_gamepad *gamepad = pcu->gamepad;
 349
 350        input_unregister_device(gamepad->input);
 351        kfree(gamepad);
 352}
 353
 354
 355/*********************************************************************
 356 *             PCU Communication protocol handling                   *
 357 *********************************************************************/
 358
 359#define IMS_PCU_PROTOCOL_STX            0x02
 360#define IMS_PCU_PROTOCOL_ETX            0x03
 361#define IMS_PCU_PROTOCOL_DLE            0x10
 362
 363/* PCU commands */
 364#define IMS_PCU_CMD_STATUS              0xa0
 365#define IMS_PCU_CMD_PCU_RESET           0xa1
 366#define IMS_PCU_CMD_RESET_REASON        0xa2
 367#define IMS_PCU_CMD_SEND_BUTTONS        0xa3
 368#define IMS_PCU_CMD_JUMP_TO_BTLDR       0xa4
 369#define IMS_PCU_CMD_GET_INFO            0xa5
 370#define IMS_PCU_CMD_SET_BRIGHTNESS      0xa6
 371#define IMS_PCU_CMD_EEPROM              0xa7
 372#define IMS_PCU_CMD_GET_FW_VERSION      0xa8
 373#define IMS_PCU_CMD_GET_BL_VERSION      0xa9
 374#define IMS_PCU_CMD_SET_INFO            0xab
 375#define IMS_PCU_CMD_GET_BRIGHTNESS      0xac
 376#define IMS_PCU_CMD_GET_DEVICE_ID       0xae
 377#define IMS_PCU_CMD_SPECIAL_INFO        0xb0
 378#define IMS_PCU_CMD_BOOTLOADER          0xb1    /* Pass data to bootloader */
 379#define IMS_PCU_CMD_OFN_SET_CONFIG      0xb3
 380#define IMS_PCU_CMD_OFN_GET_CONFIG      0xb4
 381
 382/* PCU responses */
 383#define IMS_PCU_RSP_STATUS              0xc0
 384#define IMS_PCU_RSP_PCU_RESET           0       /* Originally 0xc1 */
 385#define IMS_PCU_RSP_RESET_REASON        0xc2
 386#define IMS_PCU_RSP_SEND_BUTTONS        0xc3
 387#define IMS_PCU_RSP_JUMP_TO_BTLDR       0       /* Originally 0xc4 */
 388#define IMS_PCU_RSP_GET_INFO            0xc5
 389#define IMS_PCU_RSP_SET_BRIGHTNESS      0xc6
 390#define IMS_PCU_RSP_EEPROM              0xc7
 391#define IMS_PCU_RSP_GET_FW_VERSION      0xc8
 392#define IMS_PCU_RSP_GET_BL_VERSION      0xc9
 393#define IMS_PCU_RSP_SET_INFO            0xcb
 394#define IMS_PCU_RSP_GET_BRIGHTNESS      0xcc
 395#define IMS_PCU_RSP_CMD_INVALID         0xcd
 396#define IMS_PCU_RSP_GET_DEVICE_ID       0xce
 397#define IMS_PCU_RSP_SPECIAL_INFO        0xd0
 398#define IMS_PCU_RSP_BOOTLOADER          0xd1    /* Bootloader response */
 399#define IMS_PCU_RSP_OFN_SET_CONFIG      0xd2
 400#define IMS_PCU_RSP_OFN_GET_CONFIG      0xd3
 401
 402
 403#define IMS_PCU_RSP_EVNT_BUTTONS        0xe0    /* Unsolicited, button state */
 404#define IMS_PCU_GAMEPAD_MASK            0x0001ff80UL    /* Bits 7 through 16 */
 405
 406
 407#define IMS_PCU_MIN_PACKET_LEN          3
 408#define IMS_PCU_DATA_OFFSET             2
 409
 410#define IMS_PCU_CMD_WRITE_TIMEOUT       100 /* msec */
 411#define IMS_PCU_CMD_RESPONSE_TIMEOUT    500 /* msec */
 412
 413static void ims_pcu_report_events(struct ims_pcu *pcu)
 414{
 415        u32 data = get_unaligned_be32(&pcu->read_buf[3]);
 416
 417        ims_pcu_buttons_report(pcu, data & ~IMS_PCU_GAMEPAD_MASK);
 418        if (pcu->gamepad)
 419                ims_pcu_gamepad_report(pcu, data);
 420}
 421
 422static void ims_pcu_handle_response(struct ims_pcu *pcu)
 423{
 424        switch (pcu->read_buf[0]) {
 425        case IMS_PCU_RSP_EVNT_BUTTONS:
 426                if (likely(pcu->setup_complete))
 427                        ims_pcu_report_events(pcu);
 428                break;
 429
 430        default:
 431                /*
 432                 * See if we got command completion.
 433                 * If both the sequence and response code match save
 434                 * the data and signal completion.
 435                 */
 436                if (pcu->read_buf[0] == pcu->expected_response &&
 437                    pcu->read_buf[1] == pcu->ack_id - 1) {
 438
 439                        memcpy(pcu->cmd_buf, pcu->read_buf, pcu->read_pos);
 440                        pcu->cmd_buf_len = pcu->read_pos;
 441                        complete(&pcu->cmd_done);
 442                }
 443                break;
 444        }
 445}
 446
 447static void ims_pcu_process_data(struct ims_pcu *pcu, struct urb *urb)
 448{
 449        int i;
 450
 451        for (i = 0; i < urb->actual_length; i++) {
 452                u8 data = pcu->urb_in_buf[i];
 453
 454                /* Skip everything until we get Start Xmit */
 455                if (!pcu->have_stx && data != IMS_PCU_PROTOCOL_STX)
 456                        continue;
 457
 458                if (pcu->have_dle) {
 459                        pcu->have_dle = false;
 460                        pcu->read_buf[pcu->read_pos++] = data;
 461                        pcu->check_sum += data;
 462                        continue;
 463                }
 464
 465                switch (data) {
 466                case IMS_PCU_PROTOCOL_STX:
 467                        if (pcu->have_stx)
 468                                dev_warn(pcu->dev,
 469                                         "Unexpected STX at byte %d, discarding old data\n",
 470                                         pcu->read_pos);
 471                        pcu->have_stx = true;
 472                        pcu->have_dle = false;
 473                        pcu->read_pos = 0;
 474                        pcu->check_sum = 0;
 475                        break;
 476
 477                case IMS_PCU_PROTOCOL_DLE:
 478                        pcu->have_dle = true;
 479                        break;
 480
 481                case IMS_PCU_PROTOCOL_ETX:
 482                        if (pcu->read_pos < IMS_PCU_MIN_PACKET_LEN) {
 483                                dev_warn(pcu->dev,
 484                                         "Short packet received (%d bytes), ignoring\n",
 485                                         pcu->read_pos);
 486                        } else if (pcu->check_sum != 0) {
 487                                dev_warn(pcu->dev,
 488                                         "Invalid checksum in packet (%d bytes), ignoring\n",
 489                                         pcu->read_pos);
 490                        } else {
 491                                ims_pcu_handle_response(pcu);
 492                        }
 493
 494                        pcu->have_stx = false;
 495                        pcu->have_dle = false;
 496                        pcu->read_pos = 0;
 497                        break;
 498
 499                default:
 500                        pcu->read_buf[pcu->read_pos++] = data;
 501                        pcu->check_sum += data;
 502                        break;
 503                }
 504        }
 505}
 506
 507static bool ims_pcu_byte_needs_escape(u8 byte)
 508{
 509        return byte == IMS_PCU_PROTOCOL_STX ||
 510               byte == IMS_PCU_PROTOCOL_ETX ||
 511               byte == IMS_PCU_PROTOCOL_DLE;
 512}
 513
 514static int ims_pcu_send_cmd_chunk(struct ims_pcu *pcu,
 515                                  u8 command, int chunk, int len)
 516{
 517        int error;
 518
 519        error = usb_bulk_msg(pcu->udev,
 520                             usb_sndbulkpipe(pcu->udev,
 521                                             pcu->ep_out->bEndpointAddress),
 522                             pcu->urb_out_buf, len,
 523                             NULL, IMS_PCU_CMD_WRITE_TIMEOUT);
 524        if (error < 0) {
 525                dev_dbg(pcu->dev,
 526                        "Sending 0x%02x command failed at chunk %d: %d\n",
 527                        command, chunk, error);
 528                return error;
 529        }
 530
 531        return 0;
 532}
 533
 534static int ims_pcu_send_command(struct ims_pcu *pcu,
 535                                u8 command, const u8 *data, int len)
 536{
 537        int count = 0;
 538        int chunk = 0;
 539        int delta;
 540        int i;
 541        int error;
 542        u8 csum = 0;
 543        u8 ack_id;
 544
 545        pcu->urb_out_buf[count++] = IMS_PCU_PROTOCOL_STX;
 546
 547        /* We know the command need not be escaped */
 548        pcu->urb_out_buf[count++] = command;
 549        csum += command;
 550
 551        ack_id = pcu->ack_id++;
 552        if (ack_id == 0xff)
 553                ack_id = pcu->ack_id++;
 554
 555        if (ims_pcu_byte_needs_escape(ack_id))
 556                pcu->urb_out_buf[count++] = IMS_PCU_PROTOCOL_DLE;
 557
 558        pcu->urb_out_buf[count++] = ack_id;
 559        csum += ack_id;
 560
 561        for (i = 0; i < len; i++) {
 562
 563                delta = ims_pcu_byte_needs_escape(data[i]) ? 2 : 1;
 564                if (count + delta >= pcu->max_out_size) {
 565                        error = ims_pcu_send_cmd_chunk(pcu, command,
 566                                                       ++chunk, count);
 567                        if (error)
 568                                return error;
 569
 570                        count = 0;
 571                }
 572
 573                if (delta == 2)
 574                        pcu->urb_out_buf[count++] = IMS_PCU_PROTOCOL_DLE;
 575
 576                pcu->urb_out_buf[count++] = data[i];
 577                csum += data[i];
 578        }
 579
 580        csum = 1 + ~csum;
 581
 582        delta = ims_pcu_byte_needs_escape(csum) ? 3 : 2;
 583        if (count + delta >= pcu->max_out_size) {
 584                error = ims_pcu_send_cmd_chunk(pcu, command, ++chunk, count);
 585                if (error)
 586                        return error;
 587
 588                count = 0;
 589        }
 590
 591        if (delta == 3)
 592                pcu->urb_out_buf[count++] = IMS_PCU_PROTOCOL_DLE;
 593
 594        pcu->urb_out_buf[count++] = csum;
 595        pcu->urb_out_buf[count++] = IMS_PCU_PROTOCOL_ETX;
 596
 597        return ims_pcu_send_cmd_chunk(pcu, command, ++chunk, count);
 598}
 599
 600static int __ims_pcu_execute_command(struct ims_pcu *pcu,
 601                                     u8 command, const void *data, size_t len,
 602                                     u8 expected_response, int response_time)
 603{
 604        int error;
 605
 606        pcu->expected_response = expected_response;
 607        init_completion(&pcu->cmd_done);
 608
 609        error = ims_pcu_send_command(pcu, command, data, len);
 610        if (error)
 611                return error;
 612
 613        if (expected_response &&
 614            !wait_for_completion_timeout(&pcu->cmd_done,
 615                                         msecs_to_jiffies(response_time))) {
 616                dev_dbg(pcu->dev, "Command 0x%02x timed out\n", command);
 617                return -ETIMEDOUT;
 618        }
 619
 620        return 0;
 621}
 622
 623#define ims_pcu_execute_command(pcu, code, data, len)                   \
 624        __ims_pcu_execute_command(pcu,                                  \
 625                                  IMS_PCU_CMD_##code, data, len,        \
 626                                  IMS_PCU_RSP_##code,                   \
 627                                  IMS_PCU_CMD_RESPONSE_TIMEOUT)
 628
 629#define ims_pcu_execute_query(pcu, code)                                \
 630        ims_pcu_execute_command(pcu, code, NULL, 0)
 631
 632/* Bootloader commands */
 633#define IMS_PCU_BL_CMD_QUERY_DEVICE     0xa1
 634#define IMS_PCU_BL_CMD_UNLOCK_CONFIG    0xa2
 635#define IMS_PCU_BL_CMD_ERASE_APP        0xa3
 636#define IMS_PCU_BL_CMD_PROGRAM_DEVICE   0xa4
 637#define IMS_PCU_BL_CMD_PROGRAM_COMPLETE 0xa5
 638#define IMS_PCU_BL_CMD_READ_APP         0xa6
 639#define IMS_PCU_BL_CMD_RESET_DEVICE     0xa7
 640#define IMS_PCU_BL_CMD_LAUNCH_APP       0xa8
 641
 642/* Bootloader commands */
 643#define IMS_PCU_BL_RSP_QUERY_DEVICE     0xc1
 644#define IMS_PCU_BL_RSP_UNLOCK_CONFIG    0xc2
 645#define IMS_PCU_BL_RSP_ERASE_APP        0xc3
 646#define IMS_PCU_BL_RSP_PROGRAM_DEVICE   0xc4
 647#define IMS_PCU_BL_RSP_PROGRAM_COMPLETE 0xc5
 648#define IMS_PCU_BL_RSP_READ_APP         0xc6
 649#define IMS_PCU_BL_RSP_RESET_DEVICE     0       /* originally 0xa7 */
 650#define IMS_PCU_BL_RSP_LAUNCH_APP       0       /* originally 0xa8 */
 651
 652#define IMS_PCU_BL_DATA_OFFSET          3
 653
 654static int __ims_pcu_execute_bl_command(struct ims_pcu *pcu,
 655                                        u8 command, const void *data, size_t len,
 656                                        u8 expected_response, int response_time)
 657{
 658        int error;
 659
 660        pcu->cmd_buf[0] = command;
 661        if (data)
 662                memcpy(&pcu->cmd_buf[1], data, len);
 663
 664        error = __ims_pcu_execute_command(pcu,
 665                                IMS_PCU_CMD_BOOTLOADER, pcu->cmd_buf, len + 1,
 666                                expected_response ? IMS_PCU_RSP_BOOTLOADER : 0,
 667                                response_time);
 668        if (error) {
 669                dev_err(pcu->dev,
 670                        "Failure when sending 0x%02x command to bootloader, error: %d\n",
 671                        pcu->cmd_buf[0], error);
 672                return error;
 673        }
 674
 675        if (expected_response && pcu->cmd_buf[2] != expected_response) {
 676                dev_err(pcu->dev,
 677                        "Unexpected response from bootloader: 0x%02x, wanted 0x%02x\n",
 678                        pcu->cmd_buf[2], expected_response);
 679                return -EINVAL;
 680        }
 681
 682        return 0;
 683}
 684
 685#define ims_pcu_execute_bl_command(pcu, code, data, len, timeout)       \
 686        __ims_pcu_execute_bl_command(pcu,                               \
 687                                     IMS_PCU_BL_CMD_##code, data, len,  \
 688                                     IMS_PCU_BL_RSP_##code, timeout)    \
 689
 690#define IMS_PCU_INFO_PART_OFFSET        2
 691#define IMS_PCU_INFO_DOM_OFFSET         17
 692#define IMS_PCU_INFO_SERIAL_OFFSET      25
 693
 694#define IMS_PCU_SET_INFO_SIZE           31
 695
 696static int ims_pcu_get_info(struct ims_pcu *pcu)
 697{
 698        int error;
 699
 700        error = ims_pcu_execute_query(pcu, GET_INFO);
 701        if (error) {
 702                dev_err(pcu->dev,
 703                        "GET_INFO command failed, error: %d\n", error);
 704                return error;
 705        }
 706
 707        memcpy(pcu->part_number,
 708               &pcu->cmd_buf[IMS_PCU_INFO_PART_OFFSET],
 709               sizeof(pcu->part_number));
 710        memcpy(pcu->date_of_manufacturing,
 711               &pcu->cmd_buf[IMS_PCU_INFO_DOM_OFFSET],
 712               sizeof(pcu->date_of_manufacturing));
 713        memcpy(pcu->serial_number,
 714               &pcu->cmd_buf[IMS_PCU_INFO_SERIAL_OFFSET],
 715               sizeof(pcu->serial_number));
 716
 717        return 0;
 718}
 719
 720static int ims_pcu_set_info(struct ims_pcu *pcu)
 721{
 722        int error;
 723
 724        memcpy(&pcu->cmd_buf[IMS_PCU_INFO_PART_OFFSET],
 725               pcu->part_number, sizeof(pcu->part_number));
 726        memcpy(&pcu->cmd_buf[IMS_PCU_INFO_DOM_OFFSET],
 727               pcu->date_of_manufacturing, sizeof(pcu->date_of_manufacturing));
 728        memcpy(&pcu->cmd_buf[IMS_PCU_INFO_SERIAL_OFFSET],
 729               pcu->serial_number, sizeof(pcu->serial_number));
 730
 731        error = ims_pcu_execute_command(pcu, SET_INFO,
 732                                        &pcu->cmd_buf[IMS_PCU_DATA_OFFSET],
 733                                        IMS_PCU_SET_INFO_SIZE);
 734        if (error) {
 735                dev_err(pcu->dev,
 736                        "Failed to update device information, error: %d\n",
 737                        error);
 738                return error;
 739        }
 740
 741        return 0;
 742}
 743
 744static int ims_pcu_switch_to_bootloader(struct ims_pcu *pcu)
 745{
 746        int error;
 747
 748        /* Execute jump to the bootoloader */
 749        error = ims_pcu_execute_command(pcu, JUMP_TO_BTLDR, NULL, 0);
 750        if (error) {
 751                dev_err(pcu->dev,
 752                        "Failure when sending JUMP TO BOOLTLOADER command, error: %d\n",
 753                        error);
 754                return error;
 755        }
 756
 757        return 0;
 758}
 759
 760/*********************************************************************
 761 *             Firmware Update handling                              *
 762 *********************************************************************/
 763
 764#define IMS_PCU_FIRMWARE_NAME   "imspcu.fw"
 765
 766struct ims_pcu_flash_fmt {
 767        __le32 addr;
 768        u8 len;
 769        u8 data[];
 770};
 771
 772static unsigned int ims_pcu_count_fw_records(const struct firmware *fw)
 773{
 774        const struct ihex_binrec *rec = (const struct ihex_binrec *)fw->data;
 775        unsigned int count = 0;
 776
 777        while (rec) {
 778                count++;
 779                rec = ihex_next_binrec(rec);
 780        }
 781
 782        return count;
 783}
 784
 785static int ims_pcu_verify_block(struct ims_pcu *pcu,
 786                                u32 addr, u8 len, const u8 *data)
 787{
 788        struct ims_pcu_flash_fmt *fragment;
 789        int error;
 790
 791        fragment = (void *)&pcu->cmd_buf[1];
 792        put_unaligned_le32(addr, &fragment->addr);
 793        fragment->len = len;
 794
 795        error = ims_pcu_execute_bl_command(pcu, READ_APP, NULL, 5,
 796                                        IMS_PCU_CMD_RESPONSE_TIMEOUT);
 797        if (error) {
 798                dev_err(pcu->dev,
 799                        "Failed to retrieve block at 0x%08x, len %d, error: %d\n",
 800                        addr, len, error);
 801                return error;
 802        }
 803
 804        fragment = (void *)&pcu->cmd_buf[IMS_PCU_BL_DATA_OFFSET];
 805        if (get_unaligned_le32(&fragment->addr) != addr ||
 806            fragment->len != len) {
 807                dev_err(pcu->dev,
 808                        "Wrong block when retrieving 0x%08x (0x%08x), len %d (%d)\n",
 809                        addr, get_unaligned_le32(&fragment->addr),
 810                        len, fragment->len);
 811                return -EINVAL;
 812        }
 813
 814        if (memcmp(fragment->data, data, len)) {
 815                dev_err(pcu->dev,
 816                        "Mismatch in block at 0x%08x, len %d\n",
 817                        addr, len);
 818                return -EINVAL;
 819        }
 820
 821        return 0;
 822}
 823
 824static int ims_pcu_flash_firmware(struct ims_pcu *pcu,
 825                                  const struct firmware *fw,
 826                                  unsigned int n_fw_records)
 827{
 828        const struct ihex_binrec *rec = (const struct ihex_binrec *)fw->data;
 829        struct ims_pcu_flash_fmt *fragment;
 830        unsigned int count = 0;
 831        u32 addr;
 832        u8 len;
 833        int error;
 834
 835        error = ims_pcu_execute_bl_command(pcu, ERASE_APP, NULL, 0, 2000);
 836        if (error) {
 837                dev_err(pcu->dev,
 838                        "Failed to erase application image, error: %d\n",
 839                        error);
 840                return error;
 841        }
 842
 843        while (rec) {
 844                /*
 845                 * The firmware format is messed up for some reason.
 846                 * The address twice that of what is needed for some
 847                 * reason and we end up overwriting half of the data
 848                 * with the next record.
 849                 */
 850                addr = be32_to_cpu(rec->addr) / 2;
 851                len = be16_to_cpu(rec->len);
 852
 853                fragment = (void *)&pcu->cmd_buf[1];
 854                put_unaligned_le32(addr, &fragment->addr);
 855                fragment->len = len;
 856                memcpy(fragment->data, rec->data, len);
 857
 858                error = ims_pcu_execute_bl_command(pcu, PROGRAM_DEVICE,
 859                                                NULL, len + 5,
 860                                                IMS_PCU_CMD_RESPONSE_TIMEOUT);
 861                if (error) {
 862                        dev_err(pcu->dev,
 863                                "Failed to write block at 0x%08x, len %d, error: %d\n",
 864                                addr, len, error);
 865                        return error;
 866                }
 867
 868                if (addr >= pcu->fw_start_addr && addr < pcu->fw_end_addr) {
 869                        error = ims_pcu_verify_block(pcu, addr, len, rec->data);
 870                        if (error)
 871                                return error;
 872                }
 873
 874                count++;
 875                pcu->update_firmware_status = (count * 100) / n_fw_records;
 876
 877                rec = ihex_next_binrec(rec);
 878        }
 879
 880        error = ims_pcu_execute_bl_command(pcu, PROGRAM_COMPLETE,
 881                                            NULL, 0, 2000);
 882        if (error)
 883                dev_err(pcu->dev,
 884                        "Failed to send PROGRAM_COMPLETE, error: %d\n",
 885                        error);
 886
 887        return 0;
 888}
 889
 890static int ims_pcu_handle_firmware_update(struct ims_pcu *pcu,
 891                                          const struct firmware *fw)
 892{
 893        unsigned int n_fw_records;
 894        int retval;
 895
 896        dev_info(pcu->dev, "Updating firmware %s, size: %zu\n",
 897                 IMS_PCU_FIRMWARE_NAME, fw->size);
 898
 899        n_fw_records = ims_pcu_count_fw_records(fw);
 900
 901        retval = ims_pcu_flash_firmware(pcu, fw, n_fw_records);
 902        if (retval)
 903                goto out;
 904
 905        retval = ims_pcu_execute_bl_command(pcu, LAUNCH_APP, NULL, 0, 0);
 906        if (retval)
 907                dev_err(pcu->dev,
 908                        "Failed to start application image, error: %d\n",
 909                        retval);
 910
 911out:
 912        pcu->update_firmware_status = retval;
 913        sysfs_notify(&pcu->dev->kobj, NULL, "update_firmware_status");
 914        return retval;
 915}
 916
 917static void ims_pcu_process_async_firmware(const struct firmware *fw,
 918                                           void *context)
 919{
 920        struct ims_pcu *pcu = context;
 921        int error;
 922
 923        if (!fw) {
 924                dev_err(pcu->dev, "Failed to get firmware %s\n",
 925                        IMS_PCU_FIRMWARE_NAME);
 926                goto out;
 927        }
 928
 929        error = ihex_validate_fw(fw);
 930        if (error) {
 931                dev_err(pcu->dev, "Firmware %s is invalid\n",
 932                        IMS_PCU_FIRMWARE_NAME);
 933                goto out;
 934        }
 935
 936        mutex_lock(&pcu->cmd_mutex);
 937        ims_pcu_handle_firmware_update(pcu, fw);
 938        mutex_unlock(&pcu->cmd_mutex);
 939
 940        release_firmware(fw);
 941
 942out:
 943        complete(&pcu->async_firmware_done);
 944}
 945
 946/*********************************************************************
 947 *             Backlight LED device support                          *
 948 *********************************************************************/
 949
 950#define IMS_PCU_MAX_BRIGHTNESS          31998
 951
 952static void ims_pcu_backlight_work(struct work_struct *work)
 953{
 954        struct ims_pcu_backlight *backlight =
 955                        container_of(work, struct ims_pcu_backlight, work);
 956        struct ims_pcu *pcu =
 957                        container_of(backlight, struct ims_pcu, backlight);
 958        int desired_brightness = backlight->desired_brightness;
 959        __le16 br_val = cpu_to_le16(desired_brightness);
 960        int error;
 961
 962        mutex_lock(&pcu->cmd_mutex);
 963
 964        error = ims_pcu_execute_command(pcu, SET_BRIGHTNESS,
 965                                        &br_val, sizeof(br_val));
 966        if (error && error != -ENODEV)
 967                dev_warn(pcu->dev,
 968                         "Failed to set desired brightness %u, error: %d\n",
 969                         desired_brightness, error);
 970
 971        mutex_unlock(&pcu->cmd_mutex);
 972}
 973
 974static void ims_pcu_backlight_set_brightness(struct led_classdev *cdev,
 975                                             enum led_brightness value)
 976{
 977        struct ims_pcu_backlight *backlight =
 978                        container_of(cdev, struct ims_pcu_backlight, cdev);
 979
 980        backlight->desired_brightness = value;
 981        schedule_work(&backlight->work);
 982}
 983
 984static enum led_brightness
 985ims_pcu_backlight_get_brightness(struct led_classdev *cdev)
 986{
 987        struct ims_pcu_backlight *backlight =
 988                        container_of(cdev, struct ims_pcu_backlight, cdev);
 989        struct ims_pcu *pcu =
 990                        container_of(backlight, struct ims_pcu, backlight);
 991        int brightness;
 992        int error;
 993
 994        mutex_lock(&pcu->cmd_mutex);
 995
 996        error = ims_pcu_execute_query(pcu, GET_BRIGHTNESS);
 997        if (error) {
 998                dev_warn(pcu->dev,
 999                         "Failed to get current brightness, error: %d\n",
1000                         error);
1001                /* Assume the LED is OFF */
1002                brightness = LED_OFF;
1003        } else {
1004                brightness =
1005                        get_unaligned_le16(&pcu->cmd_buf[IMS_PCU_DATA_OFFSET]);
1006        }
1007
1008        mutex_unlock(&pcu->cmd_mutex);
1009
1010        return brightness;
1011}
1012
1013static int ims_pcu_setup_backlight(struct ims_pcu *pcu)
1014{
1015        struct ims_pcu_backlight *backlight = &pcu->backlight;
1016        int error;
1017
1018        INIT_WORK(&backlight->work, ims_pcu_backlight_work);
1019        snprintf(backlight->name, sizeof(backlight->name),
1020                 "pcu%d::kbd_backlight", pcu->device_no);
1021
1022        backlight->cdev.name = backlight->name;
1023        backlight->cdev.max_brightness = IMS_PCU_MAX_BRIGHTNESS;
1024        backlight->cdev.brightness_get = ims_pcu_backlight_get_brightness;
1025        backlight->cdev.brightness_set = ims_pcu_backlight_set_brightness;
1026
1027        error = led_classdev_register(pcu->dev, &backlight->cdev);
1028        if (error) {
1029                dev_err(pcu->dev,
1030                        "Failed to register backlight LED device, error: %d\n",
1031                        error);
1032                return error;
1033        }
1034
1035        return 0;
1036}
1037
1038static void ims_pcu_destroy_backlight(struct ims_pcu *pcu)
1039{
1040        struct ims_pcu_backlight *backlight = &pcu->backlight;
1041
1042        led_classdev_unregister(&backlight->cdev);
1043        cancel_work_sync(&backlight->work);
1044}
1045
1046
1047/*********************************************************************
1048 *             Sysfs attributes handling                             *
1049 *********************************************************************/
1050
1051struct ims_pcu_attribute {
1052        struct device_attribute dattr;
1053        size_t field_offset;
1054        int field_length;
1055};
1056
1057static ssize_t ims_pcu_attribute_show(struct device *dev,
1058                                      struct device_attribute *dattr,
1059                                      char *buf)
1060{
1061        struct usb_interface *intf = to_usb_interface(dev);
1062        struct ims_pcu *pcu = usb_get_intfdata(intf);
1063        struct ims_pcu_attribute *attr =
1064                        container_of(dattr, struct ims_pcu_attribute, dattr);
1065        char *field = (char *)pcu + attr->field_offset;
1066
1067        return scnprintf(buf, PAGE_SIZE, "%.*s\n", attr->field_length, field);
1068}
1069
1070static ssize_t ims_pcu_attribute_store(struct device *dev,
1071                                       struct device_attribute *dattr,
1072                                       const char *buf, size_t count)
1073{
1074
1075        struct usb_interface *intf = to_usb_interface(dev);
1076        struct ims_pcu *pcu = usb_get_intfdata(intf);
1077        struct ims_pcu_attribute *attr =
1078                        container_of(dattr, struct ims_pcu_attribute, dattr);
1079        char *field = (char *)pcu + attr->field_offset;
1080        size_t data_len;
1081        int error;
1082
1083        if (count > attr->field_length)
1084                return -EINVAL;
1085
1086        data_len = strnlen(buf, attr->field_length);
1087        if (data_len > attr->field_length)
1088                return -EINVAL;
1089
1090        error = mutex_lock_interruptible(&pcu->cmd_mutex);
1091        if (error)
1092                return error;
1093
1094        memset(field, 0, attr->field_length);
1095        memcpy(field, buf, data_len);
1096
1097        error = ims_pcu_set_info(pcu);
1098
1099        /*
1100         * Even if update failed, let's fetch the info again as we just
1101         * clobbered one of the fields.
1102         */
1103        ims_pcu_get_info(pcu);
1104
1105        mutex_unlock(&pcu->cmd_mutex);
1106
1107        return error < 0 ? error : count;
1108}
1109
1110#define IMS_PCU_ATTR(_field, _mode)                                     \
1111struct ims_pcu_attribute ims_pcu_attr_##_field = {                      \
1112        .dattr = __ATTR(_field, _mode,                                  \
1113                        ims_pcu_attribute_show,                         \
1114                        ims_pcu_attribute_store),                       \
1115        .field_offset = offsetof(struct ims_pcu, _field),               \
1116        .field_length = sizeof(((struct ims_pcu *)NULL)->_field),       \
1117}
1118
1119#define IMS_PCU_RO_ATTR(_field)                                         \
1120                IMS_PCU_ATTR(_field, S_IRUGO)
1121#define IMS_PCU_RW_ATTR(_field)                                         \
1122                IMS_PCU_ATTR(_field, S_IRUGO | S_IWUSR)
1123
1124static IMS_PCU_RW_ATTR(part_number);
1125static IMS_PCU_RW_ATTR(serial_number);
1126static IMS_PCU_RW_ATTR(date_of_manufacturing);
1127
1128static IMS_PCU_RO_ATTR(fw_version);
1129static IMS_PCU_RO_ATTR(bl_version);
1130static IMS_PCU_RO_ATTR(reset_reason);
1131
1132static ssize_t ims_pcu_reset_device(struct device *dev,
1133                                    struct device_attribute *dattr,
1134                                    const char *buf, size_t count)
1135{
1136        static const u8 reset_byte = 1;
1137        struct usb_interface *intf = to_usb_interface(dev);
1138        struct ims_pcu *pcu = usb_get_intfdata(intf);
1139        int value;
1140        int error;
1141
1142        error = kstrtoint(buf, 0, &value);
1143        if (error)
1144                return error;
1145
1146        if (value != 1)
1147                return -EINVAL;
1148
1149        dev_info(pcu->dev, "Attempting to reset device\n");
1150
1151        error = ims_pcu_execute_command(pcu, PCU_RESET, &reset_byte, 1);
1152        if (error) {
1153                dev_info(pcu->dev,
1154                         "Failed to reset device, error: %d\n",
1155                         error);
1156                return error;
1157        }
1158
1159        return count;
1160}
1161
1162static DEVICE_ATTR(reset_device, S_IWUSR, NULL, ims_pcu_reset_device);
1163
1164static ssize_t ims_pcu_update_firmware_store(struct device *dev,
1165                                             struct device_attribute *dattr,
1166                                             const char *buf, size_t count)
1167{
1168        struct usb_interface *intf = to_usb_interface(dev);
1169        struct ims_pcu *pcu = usb_get_intfdata(intf);
1170        const struct firmware *fw = NULL;
1171        int value;
1172        int error;
1173
1174        error = kstrtoint(buf, 0, &value);
1175        if (error)
1176                return error;
1177
1178        if (value != 1)
1179                return -EINVAL;
1180
1181        error = mutex_lock_interruptible(&pcu->cmd_mutex);
1182        if (error)
1183                return error;
1184
1185        error = request_ihex_firmware(&fw, IMS_PCU_FIRMWARE_NAME, pcu->dev);
1186        if (error) {
1187                dev_err(pcu->dev, "Failed to request firmware %s, error: %d\n",
1188                        IMS_PCU_FIRMWARE_NAME, error);
1189                goto out;
1190        }
1191
1192        /*
1193         * If we are already in bootloader mode we can proceed with
1194         * flashing the firmware.
1195         *
1196         * If we are in application mode, then we need to switch into
1197         * bootloader mode, which will cause the device to disconnect
1198         * and reconnect as different device.
1199         */
1200        if (pcu->bootloader_mode)
1201                error = ims_pcu_handle_firmware_update(pcu, fw);
1202        else
1203                error = ims_pcu_switch_to_bootloader(pcu);
1204
1205        release_firmware(fw);
1206
1207out:
1208        mutex_unlock(&pcu->cmd_mutex);
1209        return error ?: count;
1210}
1211
1212static DEVICE_ATTR(update_firmware, S_IWUSR,
1213                   NULL, ims_pcu_update_firmware_store);
1214
1215static ssize_t
1216ims_pcu_update_firmware_status_show(struct device *dev,
1217                                    struct device_attribute *dattr,
1218                                    char *buf)
1219{
1220        struct usb_interface *intf = to_usb_interface(dev);
1221        struct ims_pcu *pcu = usb_get_intfdata(intf);
1222
1223        return scnprintf(buf, PAGE_SIZE, "%d\n", pcu->update_firmware_status);
1224}
1225
1226static DEVICE_ATTR(update_firmware_status, S_IRUGO,
1227                   ims_pcu_update_firmware_status_show, NULL);
1228
1229static struct attribute *ims_pcu_attrs[] = {
1230        &ims_pcu_attr_part_number.dattr.attr,
1231        &ims_pcu_attr_serial_number.dattr.attr,
1232        &ims_pcu_attr_date_of_manufacturing.dattr.attr,
1233        &ims_pcu_attr_fw_version.dattr.attr,
1234        &ims_pcu_attr_bl_version.dattr.attr,
1235        &ims_pcu_attr_reset_reason.dattr.attr,
1236        &dev_attr_reset_device.attr,
1237        &dev_attr_update_firmware.attr,
1238        &dev_attr_update_firmware_status.attr,
1239        NULL
1240};
1241
1242static umode_t ims_pcu_is_attr_visible(struct kobject *kobj,
1243                                       struct attribute *attr, int n)
1244{
1245        struct device *dev = container_of(kobj, struct device, kobj);
1246        struct usb_interface *intf = to_usb_interface(dev);
1247        struct ims_pcu *pcu = usb_get_intfdata(intf);
1248        umode_t mode = attr->mode;
1249
1250        if (pcu->bootloader_mode) {
1251                if (attr != &dev_attr_update_firmware_status.attr &&
1252                    attr != &dev_attr_update_firmware.attr &&
1253                    attr != &dev_attr_reset_device.attr) {
1254                        mode = 0;
1255                }
1256        } else {
1257                if (attr == &dev_attr_update_firmware_status.attr)
1258                        mode = 0;
1259        }
1260
1261        return mode;
1262}
1263
1264static const struct attribute_group ims_pcu_attr_group = {
1265        .is_visible     = ims_pcu_is_attr_visible,
1266        .attrs          = ims_pcu_attrs,
1267};
1268
1269/* Support for a separate OFN attribute group */
1270
1271#define OFN_REG_RESULT_OFFSET   2
1272
1273static int ims_pcu_read_ofn_config(struct ims_pcu *pcu, u8 addr, u8 *data)
1274{
1275        int error;
1276        s16 result;
1277
1278        error = ims_pcu_execute_command(pcu, OFN_GET_CONFIG,
1279                                        &addr, sizeof(addr));
1280        if (error)
1281                return error;
1282
1283        result = (s16)get_unaligned_le16(pcu->cmd_buf + OFN_REG_RESULT_OFFSET);
1284        if (result < 0)
1285                return -EIO;
1286
1287        /* We only need LSB */
1288        *data = pcu->cmd_buf[OFN_REG_RESULT_OFFSET];
1289        return 0;
1290}
1291
1292static int ims_pcu_write_ofn_config(struct ims_pcu *pcu, u8 addr, u8 data)
1293{
1294        u8 buffer[] = { addr, data };
1295        int error;
1296        s16 result;
1297
1298        error = ims_pcu_execute_command(pcu, OFN_SET_CONFIG,
1299                                        &buffer, sizeof(buffer));
1300        if (error)
1301                return error;
1302
1303        result = (s16)get_unaligned_le16(pcu->cmd_buf + OFN_REG_RESULT_OFFSET);
1304        if (result < 0)
1305                return -EIO;
1306
1307        return 0;
1308}
1309
1310static ssize_t ims_pcu_ofn_reg_data_show(struct device *dev,
1311                                         struct device_attribute *dattr,
1312                                         char *buf)
1313{
1314        struct usb_interface *intf = to_usb_interface(dev);
1315        struct ims_pcu *pcu = usb_get_intfdata(intf);
1316        int error;
1317        u8 data;
1318
1319        mutex_lock(&pcu->cmd_mutex);
1320        error = ims_pcu_read_ofn_config(pcu, pcu->ofn_reg_addr, &data);
1321        mutex_unlock(&pcu->cmd_mutex);
1322
1323        if (error)
1324                return error;
1325
1326        return scnprintf(buf, PAGE_SIZE, "%x\n", data);
1327}
1328
1329static ssize_t ims_pcu_ofn_reg_data_store(struct device *dev,
1330                                          struct device_attribute *dattr,
1331                                          const char *buf, size_t count)
1332{
1333        struct usb_interface *intf = to_usb_interface(dev);
1334        struct ims_pcu *pcu = usb_get_intfdata(intf);
1335        int error;
1336        u8 value;
1337
1338        error = kstrtou8(buf, 0, &value);
1339        if (error)
1340                return error;
1341
1342        mutex_lock(&pcu->cmd_mutex);
1343        error = ims_pcu_write_ofn_config(pcu, pcu->ofn_reg_addr, value);
1344        mutex_unlock(&pcu->cmd_mutex);
1345
1346        return error ?: count;
1347}
1348
1349static DEVICE_ATTR(reg_data, S_IRUGO | S_IWUSR,
1350                   ims_pcu_ofn_reg_data_show, ims_pcu_ofn_reg_data_store);
1351
1352static ssize_t ims_pcu_ofn_reg_addr_show(struct device *dev,
1353                                         struct device_attribute *dattr,
1354                                         char *buf)
1355{
1356        struct usb_interface *intf = to_usb_interface(dev);
1357        struct ims_pcu *pcu = usb_get_intfdata(intf);
1358        int error;
1359
1360        mutex_lock(&pcu->cmd_mutex);
1361        error = scnprintf(buf, PAGE_SIZE, "%x\n", pcu->ofn_reg_addr);
1362        mutex_unlock(&pcu->cmd_mutex);
1363
1364        return error;
1365}
1366
1367static ssize_t ims_pcu_ofn_reg_addr_store(struct device *dev,
1368                                          struct device_attribute *dattr,
1369                                          const char *buf, size_t count)
1370{
1371        struct usb_interface *intf = to_usb_interface(dev);
1372        struct ims_pcu *pcu = usb_get_intfdata(intf);
1373        int error;
1374        u8 value;
1375
1376        error = kstrtou8(buf, 0, &value);
1377        if (error)
1378                return error;
1379
1380        mutex_lock(&pcu->cmd_mutex);
1381        pcu->ofn_reg_addr = value;
1382        mutex_unlock(&pcu->cmd_mutex);
1383
1384        return count;
1385}
1386
1387static DEVICE_ATTR(reg_addr, S_IRUGO | S_IWUSR,
1388                   ims_pcu_ofn_reg_addr_show, ims_pcu_ofn_reg_addr_store);
1389
1390struct ims_pcu_ofn_bit_attribute {
1391        struct device_attribute dattr;
1392        u8 addr;
1393        u8 nr;
1394};
1395
1396static ssize_t ims_pcu_ofn_bit_show(struct device *dev,
1397                                    struct device_attribute *dattr,
1398                                    char *buf)
1399{
1400        struct usb_interface *intf = to_usb_interface(dev);
1401        struct ims_pcu *pcu = usb_get_intfdata(intf);
1402        struct ims_pcu_ofn_bit_attribute *attr =
1403                container_of(dattr, struct ims_pcu_ofn_bit_attribute, dattr);
1404        int error;
1405        u8 data;
1406
1407        mutex_lock(&pcu->cmd_mutex);
1408        error = ims_pcu_read_ofn_config(pcu, attr->addr, &data);
1409        mutex_unlock(&pcu->cmd_mutex);
1410
1411        if (error)
1412                return error;
1413
1414        return scnprintf(buf, PAGE_SIZE, "%d\n", !!(data & (1 << attr->nr)));
1415}
1416
1417static ssize_t ims_pcu_ofn_bit_store(struct device *dev,
1418                                     struct device_attribute *dattr,
1419                                     const char *buf, size_t count)
1420{
1421        struct usb_interface *intf = to_usb_interface(dev);
1422        struct ims_pcu *pcu = usb_get_intfdata(intf);
1423        struct ims_pcu_ofn_bit_attribute *attr =
1424                container_of(dattr, struct ims_pcu_ofn_bit_attribute, dattr);
1425        int error;
1426        int value;
1427        u8 data;
1428
1429        error = kstrtoint(buf, 0, &value);
1430        if (error)
1431                return error;
1432
1433        if (value > 1)
1434                return -EINVAL;
1435
1436        mutex_lock(&pcu->cmd_mutex);
1437
1438        error = ims_pcu_read_ofn_config(pcu, attr->addr, &data);
1439        if (!error) {
1440                if (value)
1441                        data |= 1U << attr->nr;
1442                else
1443                        data &= ~(1U << attr->nr);
1444
1445                error = ims_pcu_write_ofn_config(pcu, attr->addr, data);
1446        }
1447
1448        mutex_unlock(&pcu->cmd_mutex);
1449
1450        return error ?: count;
1451}
1452
1453#define IMS_PCU_OFN_BIT_ATTR(_field, _addr, _nr)                        \
1454struct ims_pcu_ofn_bit_attribute ims_pcu_ofn_attr_##_field = {          \
1455        .dattr = __ATTR(_field, S_IWUSR | S_IRUGO,                      \
1456                        ims_pcu_ofn_bit_show, ims_pcu_ofn_bit_store),   \
1457        .addr = _addr,                                                  \
1458        .nr = _nr,                                                      \
1459}
1460
1461static IMS_PCU_OFN_BIT_ATTR(engine_enable,   0x60, 7);
1462static IMS_PCU_OFN_BIT_ATTR(speed_enable,    0x60, 6);
1463static IMS_PCU_OFN_BIT_ATTR(assert_enable,   0x60, 5);
1464static IMS_PCU_OFN_BIT_ATTR(xyquant_enable,  0x60, 4);
1465static IMS_PCU_OFN_BIT_ATTR(xyscale_enable,  0x60, 1);
1466
1467static IMS_PCU_OFN_BIT_ATTR(scale_x2,        0x63, 6);
1468static IMS_PCU_OFN_BIT_ATTR(scale_y2,        0x63, 7);
1469
1470static struct attribute *ims_pcu_ofn_attrs[] = {
1471        &dev_attr_reg_data.attr,
1472        &dev_attr_reg_addr.attr,
1473        &ims_pcu_ofn_attr_engine_enable.dattr.attr,
1474        &ims_pcu_ofn_attr_speed_enable.dattr.attr,
1475        &ims_pcu_ofn_attr_assert_enable.dattr.attr,
1476        &ims_pcu_ofn_attr_xyquant_enable.dattr.attr,
1477        &ims_pcu_ofn_attr_xyscale_enable.dattr.attr,
1478        &ims_pcu_ofn_attr_scale_x2.dattr.attr,
1479        &ims_pcu_ofn_attr_scale_y2.dattr.attr,
1480        NULL
1481};
1482
1483static const struct attribute_group ims_pcu_ofn_attr_group = {
1484        .name   = "ofn",
1485        .attrs  = ims_pcu_ofn_attrs,
1486};
1487
1488static void ims_pcu_irq(struct urb *urb)
1489{
1490        struct ims_pcu *pcu = urb->context;
1491        int retval, status;
1492
1493        status = urb->status;
1494
1495        switch (status) {
1496        case 0:
1497                /* success */
1498                break;
1499        case -ECONNRESET:
1500        case -ENOENT:
1501        case -ESHUTDOWN:
1502                /* this urb is terminated, clean up */
1503                dev_dbg(pcu->dev, "%s - urb shutting down with status: %d\n",
1504                        __func__, status);
1505                return;
1506        default:
1507                dev_dbg(pcu->dev, "%s - nonzero urb status received: %d\n",
1508                        __func__, status);
1509                goto exit;
1510        }
1511
1512        dev_dbg(pcu->dev, "%s: received %d: %*ph\n", __func__,
1513                urb->actual_length, urb->actual_length, pcu->urb_in_buf);
1514
1515        if (urb == pcu->urb_in)
1516                ims_pcu_process_data(pcu, urb);
1517
1518exit:
1519        retval = usb_submit_urb(urb, GFP_ATOMIC);
1520        if (retval && retval != -ENODEV)
1521                dev_err(pcu->dev, "%s - usb_submit_urb failed with result %d\n",
1522                        __func__, retval);
1523}
1524
1525static int ims_pcu_buffers_alloc(struct ims_pcu *pcu)
1526{
1527        int error;
1528
1529        pcu->urb_in_buf = usb_alloc_coherent(pcu->udev, pcu->max_in_size,
1530                                             GFP_KERNEL, &pcu->read_dma);
1531        if (!pcu->urb_in_buf) {
1532                dev_err(pcu->dev,
1533                        "Failed to allocate memory for read buffer\n");
1534                return -ENOMEM;
1535        }
1536
1537        pcu->urb_in = usb_alloc_urb(0, GFP_KERNEL);
1538        if (!pcu->urb_in) {
1539                dev_err(pcu->dev, "Failed to allocate input URB\n");
1540                error = -ENOMEM;
1541                goto err_free_urb_in_buf;
1542        }
1543
1544        pcu->urb_in->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1545        pcu->urb_in->transfer_dma = pcu->read_dma;
1546
1547        usb_fill_bulk_urb(pcu->urb_in, pcu->udev,
1548                          usb_rcvbulkpipe(pcu->udev,
1549                                          pcu->ep_in->bEndpointAddress),
1550                          pcu->urb_in_buf, pcu->max_in_size,
1551                          ims_pcu_irq, pcu);
1552
1553        /*
1554         * We are using usb_bulk_msg() for sending so there is no point
1555         * in allocating memory with usb_alloc_coherent().
1556         */
1557        pcu->urb_out_buf = kmalloc(pcu->max_out_size, GFP_KERNEL);
1558        if (!pcu->urb_out_buf) {
1559                dev_err(pcu->dev, "Failed to allocate memory for write buffer\n");
1560                error = -ENOMEM;
1561                goto err_free_in_urb;
1562        }
1563
1564        pcu->urb_ctrl_buf = usb_alloc_coherent(pcu->udev, pcu->max_ctrl_size,
1565                                               GFP_KERNEL, &pcu->ctrl_dma);
1566        if (!pcu->urb_ctrl_buf) {
1567                dev_err(pcu->dev,
1568                        "Failed to allocate memory for read buffer\n");
1569                error = -ENOMEM;
1570                goto err_free_urb_out_buf;
1571        }
1572
1573        pcu->urb_ctrl = usb_alloc_urb(0, GFP_KERNEL);
1574        if (!pcu->urb_ctrl) {
1575                dev_err(pcu->dev, "Failed to allocate input URB\n");
1576                error = -ENOMEM;
1577                goto err_free_urb_ctrl_buf;
1578        }
1579
1580        pcu->urb_ctrl->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
1581        pcu->urb_ctrl->transfer_dma = pcu->ctrl_dma;
1582
1583        usb_fill_int_urb(pcu->urb_ctrl, pcu->udev,
1584                          usb_rcvintpipe(pcu->udev,
1585                                         pcu->ep_ctrl->bEndpointAddress),
1586                          pcu->urb_ctrl_buf, pcu->max_ctrl_size,
1587                          ims_pcu_irq, pcu, pcu->ep_ctrl->bInterval);
1588
1589        return 0;
1590
1591err_free_urb_ctrl_buf:
1592        usb_free_coherent(pcu->udev, pcu->max_ctrl_size,
1593                          pcu->urb_ctrl_buf, pcu->ctrl_dma);
1594err_free_urb_out_buf:
1595        kfree(pcu->urb_out_buf);
1596err_free_in_urb:
1597        usb_free_urb(pcu->urb_in);
1598err_free_urb_in_buf:
1599        usb_free_coherent(pcu->udev, pcu->max_in_size,
1600                          pcu->urb_in_buf, pcu->read_dma);
1601        return error;
1602}
1603
1604static void ims_pcu_buffers_free(struct ims_pcu *pcu)
1605{
1606        usb_kill_urb(pcu->urb_in);
1607        usb_free_urb(pcu->urb_in);
1608
1609        usb_free_coherent(pcu->udev, pcu->max_out_size,
1610                          pcu->urb_in_buf, pcu->read_dma);
1611
1612        kfree(pcu->urb_out_buf);
1613
1614        usb_kill_urb(pcu->urb_ctrl);
1615        usb_free_urb(pcu->urb_ctrl);
1616
1617        usb_free_coherent(pcu->udev, pcu->max_ctrl_size,
1618                          pcu->urb_ctrl_buf, pcu->ctrl_dma);
1619}
1620
1621static const struct usb_cdc_union_desc *
1622ims_pcu_get_cdc_union_desc(struct usb_interface *intf)
1623{
1624        const void *buf = intf->altsetting->extra;
1625        size_t buflen = intf->altsetting->extralen;
1626        struct usb_cdc_union_desc *union_desc;
1627
1628        if (!buf) {
1629                dev_err(&intf->dev, "Missing descriptor data\n");
1630                return NULL;
1631        }
1632
1633        if (!buflen) {
1634                dev_err(&intf->dev, "Zero length descriptor\n");
1635                return NULL;
1636        }
1637
1638        while (buflen >= sizeof(*union_desc)) {
1639                union_desc = (struct usb_cdc_union_desc *)buf;
1640
1641                if (union_desc->bLength > buflen) {
1642                        dev_err(&intf->dev, "Too large descriptor\n");
1643                        return NULL;
1644                }
1645
1646                if (union_desc->bDescriptorType == USB_DT_CS_INTERFACE &&
1647                    union_desc->bDescriptorSubType == USB_CDC_UNION_TYPE) {
1648                        dev_dbg(&intf->dev, "Found union header\n");
1649
1650                        if (union_desc->bLength >= sizeof(*union_desc))
1651                                return union_desc;
1652
1653                        dev_err(&intf->dev,
1654                                "Union descriptor too short (%d vs %zd)\n",
1655                                union_desc->bLength, sizeof(*union_desc));
1656                        return NULL;
1657                }
1658
1659                buflen -= union_desc->bLength;
1660                buf += union_desc->bLength;
1661        }
1662
1663        dev_err(&intf->dev, "Missing CDC union descriptor\n");
1664        return NULL;
1665}
1666
1667static int ims_pcu_parse_cdc_data(struct usb_interface *intf, struct ims_pcu *pcu)
1668{
1669        const struct usb_cdc_union_desc *union_desc;
1670        struct usb_host_interface *alt;
1671
1672        union_desc = ims_pcu_get_cdc_union_desc(intf);
1673        if (!union_desc)
1674                return -EINVAL;
1675
1676        pcu->ctrl_intf = usb_ifnum_to_if(pcu->udev,
1677                                         union_desc->bMasterInterface0);
1678        if (!pcu->ctrl_intf)
1679                return -EINVAL;
1680
1681        alt = pcu->ctrl_intf->cur_altsetting;
1682
1683        if (alt->desc.bNumEndpoints < 1)
1684                return -ENODEV;
1685
1686        pcu->ep_ctrl = &alt->endpoint[0].desc;
1687        pcu->max_ctrl_size = usb_endpoint_maxp(pcu->ep_ctrl);
1688
1689        pcu->data_intf = usb_ifnum_to_if(pcu->udev,
1690                                         union_desc->bSlaveInterface0);
1691        if (!pcu->data_intf)
1692                return -EINVAL;
1693
1694        alt = pcu->data_intf->cur_altsetting;
1695        if (alt->desc.bNumEndpoints != 2) {
1696                dev_err(pcu->dev,
1697                        "Incorrect number of endpoints on data interface (%d)\n",
1698                        alt->desc.bNumEndpoints);
1699                return -EINVAL;
1700        }
1701
1702        pcu->ep_out = &alt->endpoint[0].desc;
1703        if (!usb_endpoint_is_bulk_out(pcu->ep_out)) {
1704                dev_err(pcu->dev,
1705                        "First endpoint on data interface is not BULK OUT\n");
1706                return -EINVAL;
1707        }
1708
1709        pcu->max_out_size = usb_endpoint_maxp(pcu->ep_out);
1710        if (pcu->max_out_size < 8) {
1711                dev_err(pcu->dev,
1712                        "Max OUT packet size is too small (%zd)\n",
1713                        pcu->max_out_size);
1714                return -EINVAL;
1715        }
1716
1717        pcu->ep_in = &alt->endpoint[1].desc;
1718        if (!usb_endpoint_is_bulk_in(pcu->ep_in)) {
1719                dev_err(pcu->dev,
1720                        "Second endpoint on data interface is not BULK IN\n");
1721                return -EINVAL;
1722        }
1723
1724        pcu->max_in_size = usb_endpoint_maxp(pcu->ep_in);
1725        if (pcu->max_in_size < 8) {
1726                dev_err(pcu->dev,
1727                        "Max IN packet size is too small (%zd)\n",
1728                        pcu->max_in_size);
1729                return -EINVAL;
1730        }
1731
1732        return 0;
1733}
1734
1735static int ims_pcu_start_io(struct ims_pcu *pcu)
1736{
1737        int error;
1738
1739        error = usb_submit_urb(pcu->urb_ctrl, GFP_KERNEL);
1740        if (error) {
1741                dev_err(pcu->dev,
1742                        "Failed to start control IO - usb_submit_urb failed with result: %d\n",
1743                        error);
1744                return -EIO;
1745        }
1746
1747        error = usb_submit_urb(pcu->urb_in, GFP_KERNEL);
1748        if (error) {
1749                dev_err(pcu->dev,
1750                        "Failed to start IO - usb_submit_urb failed with result: %d\n",
1751                        error);
1752                usb_kill_urb(pcu->urb_ctrl);
1753                return -EIO;
1754        }
1755
1756        return 0;
1757}
1758
1759static void ims_pcu_stop_io(struct ims_pcu *pcu)
1760{
1761        usb_kill_urb(pcu->urb_in);
1762        usb_kill_urb(pcu->urb_ctrl);
1763}
1764
1765static int ims_pcu_line_setup(struct ims_pcu *pcu)
1766{
1767        struct usb_host_interface *interface = pcu->ctrl_intf->cur_altsetting;
1768        struct usb_cdc_line_coding *line = (void *)pcu->cmd_buf;
1769        int error;
1770
1771        memset(line, 0, sizeof(*line));
1772        line->dwDTERate = cpu_to_le32(57600);
1773        line->bDataBits = 8;
1774
1775        error = usb_control_msg(pcu->udev, usb_sndctrlpipe(pcu->udev, 0),
1776                                USB_CDC_REQ_SET_LINE_CODING,
1777                                USB_TYPE_CLASS | USB_RECIP_INTERFACE,
1778                                0, interface->desc.bInterfaceNumber,
1779                                line, sizeof(struct usb_cdc_line_coding),
1780                                5000);
1781        if (error < 0) {
1782                dev_err(pcu->dev, "Failed to set line coding, error: %d\n",
1783                        error);
1784                return error;
1785        }
1786
1787        error = usb_control_msg(pcu->udev, usb_sndctrlpipe(pcu->udev, 0),
1788                                USB_CDC_REQ_SET_CONTROL_LINE_STATE,
1789                                USB_TYPE_CLASS | USB_RECIP_INTERFACE,
1790                                0x03, interface->desc.bInterfaceNumber,
1791                                NULL, 0, 5000);
1792        if (error < 0) {
1793                dev_err(pcu->dev, "Failed to set line state, error: %d\n",
1794                        error);
1795                return error;
1796        }
1797
1798        return 0;
1799}
1800
1801static int ims_pcu_get_device_info(struct ims_pcu *pcu)
1802{
1803        int error;
1804
1805        error = ims_pcu_get_info(pcu);
1806        if (error)
1807                return error;
1808
1809        error = ims_pcu_execute_query(pcu, GET_FW_VERSION);
1810        if (error) {
1811                dev_err(pcu->dev,
1812                        "GET_FW_VERSION command failed, error: %d\n", error);
1813                return error;
1814        }
1815
1816        snprintf(pcu->fw_version, sizeof(pcu->fw_version),
1817                 "%02d%02d%02d%02d.%c%c",
1818                 pcu->cmd_buf[2], pcu->cmd_buf[3], pcu->cmd_buf[4], pcu->cmd_buf[5],
1819                 pcu->cmd_buf[6], pcu->cmd_buf[7]);
1820
1821        error = ims_pcu_execute_query(pcu, GET_BL_VERSION);
1822        if (error) {
1823                dev_err(pcu->dev,
1824                        "GET_BL_VERSION command failed, error: %d\n", error);
1825                return error;
1826        }
1827
1828        snprintf(pcu->bl_version, sizeof(pcu->bl_version),
1829                 "%02d%02d%02d%02d.%c%c",
1830                 pcu->cmd_buf[2], pcu->cmd_buf[3], pcu->cmd_buf[4], pcu->cmd_buf[5],
1831                 pcu->cmd_buf[6], pcu->cmd_buf[7]);
1832
1833        error = ims_pcu_execute_query(pcu, RESET_REASON);
1834        if (error) {
1835                dev_err(pcu->dev,
1836                        "RESET_REASON command failed, error: %d\n", error);
1837                return error;
1838        }
1839
1840        snprintf(pcu->reset_reason, sizeof(pcu->reset_reason),
1841                 "%02x", pcu->cmd_buf[IMS_PCU_DATA_OFFSET]);
1842
1843        dev_dbg(pcu->dev,
1844                "P/N: %s, MD: %s, S/N: %s, FW: %s, BL: %s, RR: %s\n",
1845                pcu->part_number,
1846                pcu->date_of_manufacturing,
1847                pcu->serial_number,
1848                pcu->fw_version,
1849                pcu->bl_version,
1850                pcu->reset_reason);
1851
1852        return 0;
1853}
1854
1855static int ims_pcu_identify_type(struct ims_pcu *pcu, u8 *device_id)
1856{
1857        int error;
1858
1859        error = ims_pcu_execute_query(pcu, GET_DEVICE_ID);
1860        if (error) {
1861                dev_err(pcu->dev,
1862                        "GET_DEVICE_ID command failed, error: %d\n", error);
1863                return error;
1864        }
1865
1866        *device_id = pcu->cmd_buf[IMS_PCU_DATA_OFFSET];
1867        dev_dbg(pcu->dev, "Detected device ID: %d\n", *device_id);
1868
1869        return 0;
1870}
1871
1872static int ims_pcu_init_application_mode(struct ims_pcu *pcu)
1873{
1874        static atomic_t device_no = ATOMIC_INIT(-1);
1875
1876        const struct ims_pcu_device_info *info;
1877        int error;
1878
1879        error = ims_pcu_get_device_info(pcu);
1880        if (error) {
1881                /* Device does not respond to basic queries, hopeless */
1882                return error;
1883        }
1884
1885        error = ims_pcu_identify_type(pcu, &pcu->device_id);
1886        if (error) {
1887                dev_err(pcu->dev,
1888                        "Failed to identify device, error: %d\n", error);
1889                /*
1890                 * Do not signal error, but do not create input nor
1891                 * backlight devices either, let userspace figure this
1892                 * out (flash a new firmware?).
1893                 */
1894                return 0;
1895        }
1896
1897        if (pcu->device_id >= ARRAY_SIZE(ims_pcu_device_info) ||
1898            !ims_pcu_device_info[pcu->device_id].keymap) {
1899                dev_err(pcu->dev, "Device ID %d is not valid\n", pcu->device_id);
1900                /* Same as above, punt to userspace */
1901                return 0;
1902        }
1903
1904        /* Device appears to be operable, complete initialization */
1905        pcu->device_no = atomic_inc_return(&device_no);
1906
1907        /*
1908         * PCU-B devices, both GEN_1 and GEN_2 do not have OFN sensor
1909         */
1910        if (pcu->device_id != IMS_PCU_PCU_B_DEVICE_ID) {
1911                error = sysfs_create_group(&pcu->dev->kobj,
1912                                           &ims_pcu_ofn_attr_group);
1913                if (error)
1914                        return error;
1915        }
1916
1917        error = ims_pcu_setup_backlight(pcu);
1918        if (error)
1919                return error;
1920
1921        info = &ims_pcu_device_info[pcu->device_id];
1922        error = ims_pcu_setup_buttons(pcu, info->keymap, info->keymap_len);
1923        if (error)
1924                goto err_destroy_backlight;
1925
1926        if (info->has_gamepad) {
1927                error = ims_pcu_setup_gamepad(pcu);
1928                if (error)
1929                        goto err_destroy_buttons;
1930        }
1931
1932        pcu->setup_complete = true;
1933
1934        return 0;
1935
1936err_destroy_buttons:
1937        ims_pcu_destroy_buttons(pcu);
1938err_destroy_backlight:
1939        ims_pcu_destroy_backlight(pcu);
1940        return error;
1941}
1942
1943static void ims_pcu_destroy_application_mode(struct ims_pcu *pcu)
1944{
1945        if (pcu->setup_complete) {
1946                pcu->setup_complete = false;
1947                mb(); /* make sure flag setting is not reordered */
1948
1949                if (pcu->gamepad)
1950                        ims_pcu_destroy_gamepad(pcu);
1951                ims_pcu_destroy_buttons(pcu);
1952                ims_pcu_destroy_backlight(pcu);
1953
1954                if (pcu->device_id != IMS_PCU_PCU_B_DEVICE_ID)
1955                        sysfs_remove_group(&pcu->dev->kobj,
1956                                           &ims_pcu_ofn_attr_group);
1957        }
1958}
1959
1960static int ims_pcu_init_bootloader_mode(struct ims_pcu *pcu)
1961{
1962        int error;
1963
1964        error = ims_pcu_execute_bl_command(pcu, QUERY_DEVICE, NULL, 0,
1965                                           IMS_PCU_CMD_RESPONSE_TIMEOUT);
1966        if (error) {
1967                dev_err(pcu->dev, "Bootloader does not respond, aborting\n");
1968                return error;
1969        }
1970
1971        pcu->fw_start_addr =
1972                get_unaligned_le32(&pcu->cmd_buf[IMS_PCU_DATA_OFFSET + 11]);
1973        pcu->fw_end_addr =
1974                get_unaligned_le32(&pcu->cmd_buf[IMS_PCU_DATA_OFFSET + 15]);
1975
1976        dev_info(pcu->dev,
1977                 "Device is in bootloader mode (addr 0x%08x-0x%08x), requesting firmware\n",
1978                 pcu->fw_start_addr, pcu->fw_end_addr);
1979
1980        error = request_firmware_nowait(THIS_MODULE, true,
1981                                        IMS_PCU_FIRMWARE_NAME,
1982                                        pcu->dev, GFP_KERNEL, pcu,
1983                                        ims_pcu_process_async_firmware);
1984        if (error) {
1985                /* This error is not fatal, let userspace have another chance */
1986                complete(&pcu->async_firmware_done);
1987        }
1988
1989        return 0;
1990}
1991
1992static void ims_pcu_destroy_bootloader_mode(struct ims_pcu *pcu)
1993{
1994        /* Make sure our initial firmware request has completed */
1995        wait_for_completion(&pcu->async_firmware_done);
1996}
1997
1998#define IMS_PCU_APPLICATION_MODE        0
1999#define IMS_PCU_BOOTLOADER_MODE         1
2000
2001static struct usb_driver ims_pcu_driver;
2002
2003static int ims_pcu_probe(struct usb_interface *intf,
2004                         const struct usb_device_id *id)
2005{
2006        struct usb_device *udev = interface_to_usbdev(intf);
2007        struct ims_pcu *pcu;
2008        int error;
2009
2010        pcu = kzalloc(sizeof(struct ims_pcu), GFP_KERNEL);
2011        if (!pcu)
2012                return -ENOMEM;
2013
2014        pcu->dev = &intf->dev;
2015        pcu->udev = udev;
2016        pcu->bootloader_mode = id->driver_info == IMS_PCU_BOOTLOADER_MODE;
2017        mutex_init(&pcu->cmd_mutex);
2018        init_completion(&pcu->cmd_done);
2019        init_completion(&pcu->async_firmware_done);
2020
2021        error = ims_pcu_parse_cdc_data(intf, pcu);
2022        if (error)
2023                goto err_free_mem;
2024
2025        error = usb_driver_claim_interface(&ims_pcu_driver,
2026                                           pcu->data_intf, pcu);
2027        if (error) {
2028                dev_err(&intf->dev,
2029                        "Unable to claim corresponding data interface: %d\n",
2030                        error);
2031                goto err_free_mem;
2032        }
2033
2034        usb_set_intfdata(pcu->ctrl_intf, pcu);
2035        usb_set_intfdata(pcu->data_intf, pcu);
2036
2037        error = ims_pcu_buffers_alloc(pcu);
2038        if (error)
2039                goto err_unclaim_intf;
2040
2041        error = ims_pcu_start_io(pcu);
2042        if (error)
2043                goto err_free_buffers;
2044
2045        error = ims_pcu_line_setup(pcu);
2046        if (error)
2047                goto err_stop_io;
2048
2049        error = sysfs_create_group(&intf->dev.kobj, &ims_pcu_attr_group);
2050        if (error)
2051                goto err_stop_io;
2052
2053        error = pcu->bootloader_mode ?
2054                        ims_pcu_init_bootloader_mode(pcu) :
2055                        ims_pcu_init_application_mode(pcu);
2056        if (error)
2057                goto err_remove_sysfs;
2058
2059        return 0;
2060
2061err_remove_sysfs:
2062        sysfs_remove_group(&intf->dev.kobj, &ims_pcu_attr_group);
2063err_stop_io:
2064        ims_pcu_stop_io(pcu);
2065err_free_buffers:
2066        ims_pcu_buffers_free(pcu);
2067err_unclaim_intf:
2068        usb_driver_release_interface(&ims_pcu_driver, pcu->data_intf);
2069err_free_mem:
2070        kfree(pcu);
2071        return error;
2072}
2073
2074static void ims_pcu_disconnect(struct usb_interface *intf)
2075{
2076        struct ims_pcu *pcu = usb_get_intfdata(intf);
2077        struct usb_host_interface *alt = intf->cur_altsetting;
2078
2079        usb_set_intfdata(intf, NULL);
2080
2081        /*
2082         * See if we are dealing with control or data interface. The cleanup
2083         * happens when we unbind primary (control) interface.
2084         */
2085        if (alt->desc.bInterfaceClass != USB_CLASS_COMM)
2086                return;
2087
2088        sysfs_remove_group(&intf->dev.kobj, &ims_pcu_attr_group);
2089
2090        ims_pcu_stop_io(pcu);
2091
2092        if (pcu->bootloader_mode)
2093                ims_pcu_destroy_bootloader_mode(pcu);
2094        else
2095                ims_pcu_destroy_application_mode(pcu);
2096
2097        ims_pcu_buffers_free(pcu);
2098        kfree(pcu);
2099}
2100
2101#ifdef CONFIG_PM
2102static int ims_pcu_suspend(struct usb_interface *intf,
2103                           pm_message_t message)
2104{
2105        struct ims_pcu *pcu = usb_get_intfdata(intf);
2106        struct usb_host_interface *alt = intf->cur_altsetting;
2107
2108        if (alt->desc.bInterfaceClass == USB_CLASS_COMM)
2109                ims_pcu_stop_io(pcu);
2110
2111        return 0;
2112}
2113
2114static int ims_pcu_resume(struct usb_interface *intf)
2115{
2116        struct ims_pcu *pcu = usb_get_intfdata(intf);
2117        struct usb_host_interface *alt = intf->cur_altsetting;
2118        int retval = 0;
2119
2120        if (alt->desc.bInterfaceClass == USB_CLASS_COMM) {
2121                retval = ims_pcu_start_io(pcu);
2122                if (retval == 0)
2123                        retval = ims_pcu_line_setup(pcu);
2124        }
2125
2126        return retval;
2127}
2128#endif
2129
2130static const struct usb_device_id ims_pcu_id_table[] = {
2131        {
2132                USB_DEVICE_AND_INTERFACE_INFO(0x04d8, 0x0082,
2133                                        USB_CLASS_COMM,
2134                                        USB_CDC_SUBCLASS_ACM,
2135                                        USB_CDC_ACM_PROTO_AT_V25TER),
2136                .driver_info = IMS_PCU_APPLICATION_MODE,
2137        },
2138        {
2139                USB_DEVICE_AND_INTERFACE_INFO(0x04d8, 0x0083,
2140                                        USB_CLASS_COMM,
2141                                        USB_CDC_SUBCLASS_ACM,
2142                                        USB_CDC_ACM_PROTO_AT_V25TER),
2143                .driver_info = IMS_PCU_BOOTLOADER_MODE,
2144        },
2145        { }
2146};
2147
2148static struct usb_driver ims_pcu_driver = {
2149        .name                   = "ims_pcu",
2150        .id_table               = ims_pcu_id_table,
2151        .probe                  = ims_pcu_probe,
2152        .disconnect             = ims_pcu_disconnect,
2153#ifdef CONFIG_PM
2154        .suspend                = ims_pcu_suspend,
2155        .resume                 = ims_pcu_resume,
2156        .reset_resume           = ims_pcu_resume,
2157#endif
2158};
2159
2160module_usb_driver(ims_pcu_driver);
2161
2162MODULE_DESCRIPTION("IMS Passenger Control Unit driver");
2163MODULE_AUTHOR("Dmitry Torokhov <dmitry.torokhov@gmail.com>");
2164MODULE_LICENSE("GPL");
2165