source: mainline/uspace/drv/usbhid/kbd/kbddev.c@ 65b458c4

/*
 * Copyright (c) 2011 Lubos Slovak
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup drvusbhid
 * @{
 */
/**
 * @file
 * USB HID keyboard device structure and API.
 */

#include <errno.h>
#include <str_error.h>
#include <stdio.h>

#include <io/keycode.h>
#include <ipc/kbd.h>
#include <async.h>
#include <fibril.h>
#include <fibril_synch.h>

#include <usb/usb.h>
#include <usb/dp.h>
#include <usb/request.h>
#include <usb/classes/hid.h>
#include <usb/pipes.h>
#include <usb/debug.h>
#include <usb/classes/hidparser.h>
#include <usb/classes/classes.h>
#include <usb/classes/hidut.h>
#include <usb/classes/hidreq.h>
#include <usb/classes/hidreport.h>
#include <usb/classes/hid/utled.h>

#include <usb/devdrv.h>

#include "kbddev.h"

#include "layout.h"
#include "conv.h"
#include "kbdrepeat.h"

#include "../usbhid.h"

/*----------------------------------------------------------------------------*/
/** Default modifiers when the keyboard is initialized. */
static const unsigned DEFAULT_ACTIVE_MODS = KM_NUM_LOCK;

///** Boot protocol report size (key part). */
//static const size_t BOOTP_REPORT_SIZE = 6;

///** Boot protocol total report size. */
//static const size_t BOOTP_BUFFER_SIZE = 8;

///** Boot protocol output report size. */
//static const size_t BOOTP_BUFFER_OUT_SIZE = 1;

///** Boot protocol error key code. */
//static const uint8_t BOOTP_ERROR_ROLLOVER = 1;
static const uint8_t ERROR_ROLLOVER = 1;

/** Default idle rate for keyboards. */
static const uint8_t IDLE_RATE = 0;

/** Delay before a pressed key starts auto-repeating. */
static const unsigned int DEFAULT_DELAY_BEFORE_FIRST_REPEAT = 500 * 1000;

/** Delay between two repeats of a pressed key when auto-repeating. */
static const unsigned int DEFAULT_REPEAT_DELAY = 50 * 1000;

/*----------------------------------------------------------------------------*/

/** Keyboard polling endpoint description for boot protocol class. */
usb_endpoint_description_t usb_hid_kbd_poll_endpoint_description = {
        .transfer_type = USB_TRANSFER_INTERRUPT,
        .direction = USB_DIRECTION_IN,
        .interface_class = USB_CLASS_HID,
        .interface_subclass = USB_HID_SUBCLASS_BOOT,
        .interface_protocol = USB_HID_PROTOCOL_KEYBOARD,
        .flags = 0
};

//static usb_endpoint_description_t hid_poll_endpoint_description = {
//      .transfer_type = USB_TRANSFER_INTERRUPT,
//      .direction = USB_DIRECTION_IN,
//      .interface_class = USB_CLASS_HID,
//      .flags = 0
//};

///* Array of endpoints expected on the device, NULL terminated. */
//usb_endpoint_description_t 
//    *usb_kbd_endpoints[USB_KBD_POLL_EP_COUNT + 1] = {
//      &boot_poll_endpoint_description,
//      &hid_poll_endpoint_description,
//      NULL
//};

const char *HID_KBD_FUN_NAME = "keyboard";
const char *HID_KBD_CLASS_NAME = "keyboard";

/*----------------------------------------------------------------------------*/

enum {
        USB_KBD_BOOT_REPORT_DESCRIPTOR_SIZE = 63
};

static const uint8_t USB_KBD_BOOT_REPORT_DESCRIPTOR[
    USB_KBD_BOOT_REPORT_DESCRIPTOR_SIZE] = {
        0x05, 0x01,  // Usage Page (Generic Desktop),
        0x09, 0x06,  // Usage (Keyboard),
        0xA1, 0x01,  // Collection (Application),
        0x75, 0x01,  //   Report Size (1),
        0x95, 0x08,  //   Report Count (8),       
        0x05, 0x07,  //   Usage Page (Key Codes);
        0x19, 0xE0,  //   Usage Minimum (224),
        0x29, 0xE7,  //   Usage Maximum (231),
        0x15, 0x00,  //   Logical Minimum (0),
        0x25, 0x01,  //   Logical Maximum (1),
        0x81, 0x02,  //   Input (Data, Variable, Absolute),   ; Modifier byte
        0x95, 0x01,  //   Report Count (1),
        0x75, 0x08,  //   Report Size (8),
        0x81, 0x01,  //   Input (Constant),                   ; Reserved byte
        0x95, 0x05,  //   Report Count (5),
        0x75, 0x01,  //   Report Size (1),
        0x05, 0x08,  //   Usage Page (Page# for LEDs),
        0x19, 0x01,  //   Usage Minimum (1),
        0x29, 0x05,  //   Usage Maxmimum (5),
        0x91, 0x02,  //   Output (Data, Variable, Absolute),  ; LED report
        0x95, 0x01,  //   Report Count (1),
        0x75, 0x03,  //   Report Size (3),
        0x91, 0x01,  //   Output (Constant),              ; LED report padding
        0x95, 0x06,  //   Report Count (6),
        0x75, 0x08,  //   Report Size (8),
        0x15, 0x00,  //   Logical Minimum (0),
        0x25, 0xff,  //   Logical Maximum (255),
        0x05, 0x07,  //   Usage Page (Key Codes),
        0x19, 0x00,  //   Usage Minimum (0),
        0x29, 0xff,  //   Usage Maximum (255),
        0x81, 0x00,  //   Input (Data, Array),            ; Key arrays (6 bytes)
        0xC0           // End Collection

};

/*----------------------------------------------------------------------------*/

typedef enum usb_kbd_flags {
        USB_KBD_STATUS_UNINITIALIZED = 0,
        USB_KBD_STATUS_INITIALIZED = 1,
        USB_KBD_STATUS_TO_DESTROY = -1
} usb_kbd_flags;

/*----------------------------------------------------------------------------*/

//static void usb_kbd_process_keycodes(const uint8_t *key_codes, size_t count,
//    uint8_t report_id, void *arg);

//static const usb_hid_report_in_callbacks_t usb_kbd_parser_callbacks = {
//      .keyboard = usb_kbd_process_keycodes
//};

/*----------------------------------------------------------------------------*/
/* Keyboard layouts                                                           */
/*----------------------------------------------------------------------------*/

#define NUM_LAYOUTS 3

/** Keyboard layout map. */
static layout_op_t *layout[NUM_LAYOUTS] = {
        &us_qwerty_op,
        &us_dvorak_op,
        &cz_op
};

static int active_layout = 0;

/*----------------------------------------------------------------------------*/
/* Modifier constants                                                         */
/*----------------------------------------------------------------------------*/
/** Mapping of USB modifier key codes to generic modifier key codes. */
//static const keycode_t usbhid_modifiers_keycodes[USB_HID_MOD_COUNT] = {
//      KC_LCTRL,         /* USB_HID_MOD_LCTRL */
//      KC_LSHIFT,        /* USB_HID_MOD_LSHIFT */
//      KC_LALT,          /* USB_HID_MOD_LALT */
//      0,                /* USB_HID_MOD_LGUI */
//      KC_RCTRL,         /* USB_HID_MOD_RCTRL */
//      KC_RSHIFT,        /* USB_HID_MOD_RSHIFT */
//      KC_RALT,          /* USB_HID_MOD_RALT */
//      0,                /* USB_HID_MOD_RGUI */
//};

//typedef enum usbhid_lock_code {
//      USB_KBD_LOCK_NUM = 0x53,
//      USB_KBD_LOCK_CAPS = 0x39,
//      USB_KBD_LOCK_SCROLL = 0x47,
//      USB_KBD_LOCK_COUNT = 3
//} usbhid_lock_code;

//static const usbhid_lock_code usbhid_lock_codes[USB_KBD_LOCK_COUNT] = {
//      USB_KBD_LOCK_NUM,
//      USB_KBD_LOCK_CAPS,
//      USB_KBD_LOCK_SCROLL
//};

/*----------------------------------------------------------------------------*/
/* IPC method handler                                                         */
/*----------------------------------------------------------------------------*/

static void default_connection_handler(ddf_fun_t *, ipc_callid_t, ipc_call_t *);
//ddf_dev_ops_t keyboard_ops = {
//      .default_handler = default_connection_handler
//};

/** 
 * Default handler for IPC methods not handled by DDF.
 *
 * Currently recognizes only one method (IPC_M_CONNECT_TO_ME), in which case it
 * assumes the caller is the console and thus it stores IPC phone to it for 
 * later use by the driver to notify about key events.
 *
 * @param fun Device function handling the call.
 * @param icallid Call id.
 * @param icall Call data.
 */
static void default_connection_handler(ddf_fun_t *fun,
    ipc_callid_t icallid, ipc_call_t *icall)
{
        sysarg_t method = IPC_GET_IMETHOD(*icall);
        
        usb_kbd_t *kbd_dev = (usb_kbd_t *)fun->driver_data;
        if (kbd_dev == NULL) {
                usb_log_debug("default_connection_handler: "
                    "Missing parameter.\n");
                async_answer_0(icallid, EINVAL);
                return;
        }

        if (method == IPC_M_CONNECT_TO_ME) {
                int callback = IPC_GET_ARG5(*icall);

                if (kbd_dev->console_phone != -1) {
                        usb_log_debug("default_connection_handler: "
                            "console phone already set\n");
                        async_answer_0(icallid, ELIMIT);
                        return;
                }

                kbd_dev->console_phone = callback;
                
                usb_log_debug("default_connection_handler: OK\n");
                async_answer_0(icallid, EOK);
                return;
        }
        
        usb_log_debug("default_connection_handler: Wrong function.\n");
        async_answer_0(icallid, EINVAL);
}

/*----------------------------------------------------------------------------*/
/* Key processing functions                                                   */
/*----------------------------------------------------------------------------*/
/**
 * Handles turning of LED lights on and off.
 *
 * In case of USB keyboards, the LEDs are handled in the driver, not in the 
 * device. When there should be a change (lock key was pressed), the driver
 * uses a Set_Report request sent to the device to set the state of the LEDs.
 *
 * This functions sets the LED lights according to current settings of modifiers
 * kept in the keyboard device structure.
 *
 * @param kbd_dev Keyboard device structure.
 */
static void usb_kbd_set_led(usb_hid_dev_t *hid_dev, usb_kbd_t *kbd_dev) 
{
        if (kbd_dev->output_size == 0) {
                return;
        }
                
        /* Reset the LED data. */
        memset(kbd_dev->led_data, 0, kbd_dev->led_output_size * sizeof(int32_t));
        usb_log_debug("Creating output report:\n");

        usb_hid_report_field_t *field = usb_hid_report_get_sibling(
            hid_dev->report, NULL, kbd_dev->led_path, 
            USB_HID_PATH_COMPARE_END | USB_HID_PATH_COMPARE_USAGE_PAGE_ONLY,
            USB_HID_REPORT_TYPE_OUTPUT);
        
        while (field != NULL) {         
                
                if ((field->usage == USB_HID_LED_NUM_LOCK) 
                    && (kbd_dev->mods & KM_NUM_LOCK)){
                        field->value = 1;
                }

                if ((field->usage == USB_HID_LED_CAPS_LOCK) 
                    && (kbd_dev->mods & KM_CAPS_LOCK)){
                        field->value = 1;
                }

                if ((field->usage == USB_HID_LED_SCROLL_LOCK) 
                    && (kbd_dev->mods & KM_SCROLL_LOCK)){
                        field->value = 1;
                }
                
                field = usb_hid_report_get_sibling(hid_dev->report, field,
                    kbd_dev->led_path,  
                USB_HID_PATH_COMPARE_END | USB_HID_PATH_COMPARE_USAGE_PAGE_ONLY,
                        USB_HID_REPORT_TYPE_OUTPUT);
        }
        
        // TODO: what about the Report ID?
        int rc = usb_hid_report_output_translate(hid_dev->report, 0,
            kbd_dev->output_buffer, kbd_dev->output_size);
        
        if (rc != EOK) {
                usb_log_warning("Error translating LED output to output report"
                    ".\n");
                return;
        }
        
        usb_log_debug("Output report buffer: %s\n", 
            usb_debug_str_buffer(kbd_dev->output_buffer, kbd_dev->output_size, 
                0));
        
        usbhid_req_set_report(&hid_dev->usb_dev->ctrl_pipe, 
            hid_dev->usb_dev->interface_no, USB_HID_REPORT_TYPE_OUTPUT, 
            kbd_dev->output_buffer, kbd_dev->output_size);
}

/*----------------------------------------------------------------------------*/
/**
 * Processes key events.
 *
 * @note This function was copied from AT keyboard driver and modified to suit
 *       USB keyboard.
 *
 * @note Lock keys are not sent to the console, as they are completely handled
 *       in the driver. It may, however, be required later that the driver
 *       sends also these keys to application (otherwise it cannot use those
 *       keys at all).
 * 
 * @param kbd_dev Keyboard device structure.
 * @param type Type of the event (press / release). Recognized values: 
 *             KEY_PRESS, KEY_RELEASE
 * @param key Key code of the key according to HID Usage Tables.
 */
void usb_kbd_push_ev(usb_hid_dev_t *hid_dev, usb_kbd_t *kbd_dev, int type, 
    unsigned int key)
{
        console_event_t ev;
        unsigned mod_mask;

        /*
         * These parts are copy-pasted from the AT keyboard driver.
         *
         * They definitely require some refactoring, but will keep it for later
         * when the console and keyboard system is changed in HelenOS.
         */
        switch (key) {
        case KC_LCTRL: mod_mask = KM_LCTRL; break;
        case KC_RCTRL: mod_mask = KM_RCTRL; break;
        case KC_LSHIFT: mod_mask = KM_LSHIFT; break;
        case KC_RSHIFT: mod_mask = KM_RSHIFT; break;
        case KC_LALT: mod_mask = KM_LALT; break;
        case KC_RALT: mod_mask = KM_RALT; break;
        default: mod_mask = 0; break;
        }

        if (mod_mask != 0) {
                if (type == KEY_PRESS)
                        kbd_dev->mods = kbd_dev->mods | mod_mask;
                else
                        kbd_dev->mods = kbd_dev->mods & ~mod_mask;
        }

        switch (key) {
        case KC_CAPS_LOCK: mod_mask = KM_CAPS_LOCK; break;
        case KC_NUM_LOCK: mod_mask = KM_NUM_LOCK; break;
        case KC_SCROLL_LOCK: mod_mask = KM_SCROLL_LOCK; break;
        default: mod_mask = 0; break;
        }

        if (mod_mask != 0) {
                if (type == KEY_PRESS) {
                        /*
                         * Only change lock state on transition from released
                         * to pressed. This prevents autorepeat from messing
                         * up the lock state.
                         */
                        unsigned int locks_old = kbd_dev->lock_keys;
                        
                        kbd_dev->mods = 
                            kbd_dev->mods ^ (mod_mask & ~kbd_dev->lock_keys);
                        kbd_dev->lock_keys = kbd_dev->lock_keys | mod_mask;

                        /* Update keyboard lock indicator lights. */
                        if (kbd_dev->lock_keys != locks_old 
                            && hid_dev != NULL) { // ugly hack
                                usb_kbd_set_led(hid_dev, kbd_dev);
                        }
                } else {
                        kbd_dev->lock_keys = kbd_dev->lock_keys & ~mod_mask;
                }
        }

        if (key == KC_CAPS_LOCK || key == KC_NUM_LOCK || key == KC_SCROLL_LOCK) {
                // do not send anything to the console, this is our business
                return;
        }
        
        if (type == KEY_PRESS && (kbd_dev->mods & KM_LCTRL) && key == KC_F1) {
                active_layout = 0;
                layout[active_layout]->reset();
                return;
        }

        if (type == KEY_PRESS && (kbd_dev->mods & KM_LCTRL) && key == KC_F2) {
                active_layout = 1;
                layout[active_layout]->reset();
                return;
        }

        if (type == KEY_PRESS && (kbd_dev->mods & KM_LCTRL) && key == KC_F3) {
                active_layout = 2;
                layout[active_layout]->reset();
                return;
        }
        
        ev.type = type;
        ev.key = key;
        ev.mods = kbd_dev->mods;

        ev.c = layout[active_layout]->parse_ev(&ev);

        usb_log_debug2("Sending key %d to the console\n", ev.key);
        if (kbd_dev->console_phone < 0) {
                usb_log_warning(
                    "Connection to console not ready, key discarded.\n");
                return;
        }
        
        async_msg_4(kbd_dev->console_phone, KBD_EVENT, ev.type, ev.key, 
            ev.mods, ev.c);
}

/*----------------------------------------------------------------------------*/

static inline int usb_kbd_is_lock(unsigned int key_code) 
{
        return (key_code == KC_NUM_LOCK
            || key_code == KC_SCROLL_LOCK
            || key_code == KC_CAPS_LOCK);
}

/*----------------------------------------------------------------------------*/
/**
 * Checks if some keys were pressed or released and generates key events.
 *
 * An event is created only when key is pressed or released. Besides handling
 * the events (usb_kbd_push_ev()), the auto-repeat fibril is notified about
 * key presses and releases (see usb_kbd_repeat_start() and 
 * usb_kbd_repeat_stop()).
 *
 * @param kbd_dev Keyboard device structure.
 * @param key_codes Parsed keyboard report - codes of currently pressed keys 
 *                  according to HID Usage Tables.
 * @param count Number of key codes in report (size of the report).
 *
 * @sa usb_kbd_push_ev(), usb_kbd_repeat_start(), usb_kbd_repeat_stop()
 */
static void usb_kbd_check_key_changes(usb_hid_dev_t *hid_dev, 
    usb_kbd_t *kbd_dev/*, const uint8_t *key_codes, size_t count*/)
{
        unsigned int key;
        unsigned int i, j;
        
        /*
         * First of all, check if the kbd have reported phantom state.
         *
         * As there is no way to distinguish keys from modifiers, we do not have
         * a way to check that 'all keys report Error Rollover'. We thus check
         * if there is at least one such error and in such case we ignore the
         * whole input report.
         */
        i = 0;
        while (i < kbd_dev->key_count && kbd_dev->keys[i] != ERROR_ROLLOVER) {
                ++i;
        }
        if (i != kbd_dev->key_count) {
                usb_log_debug("Phantom state occured.\n");
                // phantom state, do nothing
                return;
        }
        
        /*
         * 1) Key releases
         */
        for (j = 0; j < kbd_dev->key_count; ++j) {
                // try to find the old key in the new key list
                i = 0;
                while (i < kbd_dev->key_count
                    && kbd_dev->keys[i] != kbd_dev->keys_old[j]) {
                        ++i;
                }
                
                if (i == kbd_dev->key_count) {
                        // not found, i.e. the key was released
                        key = usbhid_parse_scancode(kbd_dev->keys_old[j]);
                        if (!usb_kbd_is_lock(key)) {
                                usb_kbd_repeat_stop(kbd_dev, key);
                        }
                        usb_kbd_push_ev(hid_dev, kbd_dev, KEY_RELEASE, key);
                        usb_log_debug2("Key released: %d\n", key);
                } else {
                        // found, nothing happens
                }
        }
        
        /*
         * 1) Key presses
         */
        for (i = 0; i < kbd_dev->key_count; ++i) {
                // try to find the new key in the old key list
                j = 0;
                while (j < kbd_dev->key_count 
                    && kbd_dev->keys_old[j] != kbd_dev->keys[i]) { 
                        ++j;
                }
                
                if (j == kbd_dev->key_count) {
                        // not found, i.e. new key pressed
                        key = usbhid_parse_scancode(kbd_dev->keys[i]);
                        usb_log_debug2("Key pressed: %d (keycode: %d)\n", key,
                            kbd_dev->keys[i]);
                        if (!usb_kbd_is_lock(key)) {
                                usb_kbd_repeat_start(kbd_dev, key);
                        }
                        usb_kbd_push_ev(hid_dev, kbd_dev, KEY_PRESS, key);
                } else {
                        // found, nothing happens
                }
        }
        
//      usb_log_debug("Old keys: ");
//      for (i = 0; i < kbd_dev->key_count; ++i) {
//              usb_log_debug("%d ", kbd_dev->keys_old[i]);
//      }
//      usb_log_debug("\n");
        
        
//      usb_log_debug("New keys: ");
//      for (i = 0; i < kbd_dev->key_count; ++i) {
//              usb_log_debug("%d ", kbd_dev->keys[i]);
//      }
//      usb_log_debug("\n");
        
        memcpy(kbd_dev->keys_old, kbd_dev->keys, kbd_dev->key_count * 4);
        
        usb_log_debug2("New stored keys: ");
        for (i = 0; i < kbd_dev->key_count; ++i) {
                usb_log_debug2("%d ", kbd_dev->keys_old[i]);
        }
        usb_log_debug2("\n");
}

/*----------------------------------------------------------------------------*/
/* Callbacks for parser                                                       */
/*----------------------------------------------------------------------------*/
/**
 * Callback function for the HID report parser.
 *
 * This function is called by the HID report parser with the parsed report.
 * The parsed report is used to check if any events occured (key was pressed or
 * released, modifier was pressed or released).
 *
 * @param key_codes Parsed keyboard report - codes of currently pressed keys 
 *                  according to HID Usage Tables.
 * @param count Number of key codes in report (size of the report).
 * @param report_id
 * @param arg User-specified argument. Expects pointer to the keyboard device
 *            structure representing the keyboard.
 *
 * @sa usb_kbd_check_key_changes(), usb_kbd_check_modifier_changes()
 */
//static void usb_kbd_process_keycodes(const uint8_t *key_codes, size_t count,
//    uint8_t report_id, void *arg)
//{
//      if (arg == NULL) {
//              usb_log_warning("Missing argument in callback "
//                  "usbhid_process_keycodes().\n");
//              return;
//      }
        
//      usb_hid_dev_t *hid_dev = (usb_hid_dev_t *)arg;
        
//      if (hid_dev->data == NULL) {
//              usb_log_warning("Missing KBD device structure in callback.\n");
//              return;
//      }
        
//      usb_kbd_t *kbd_dev = (usb_kbd_t *)hid_dev->data;

//      usb_log_debug("Got keys from parser (report id: %u): %s\n", 
//          report_id, usb_debug_str_buffer(key_codes, count, 0));
        
//      if (count != kbd_dev->key_count) {
//              usb_log_warning("Number of received keycodes (%zu) differs from"
//                  " expected (%zu).\n", count, kbd_dev->key_count);
//              return;
//      }
        
//      ///usb_kbd_check_modifier_changes(kbd_dev, key_codes, count);
//      usb_kbd_check_key_changes(hid_dev, kbd_dev, key_codes, count);
//}

/*----------------------------------------------------------------------------*/
/* General kbd functions                                                      */
/*----------------------------------------------------------------------------*/
/**
 * Processes data received from the device in form of report.
 *
 * This function uses the HID report parser to translate the data received from
 * the device into generic USB HID key codes and into generic modifiers bitmap.
 * The parser then calls the given callback (usb_kbd_process_keycodes()).
 *
 * @note Currently, only the boot protocol is supported.
 *
 * @param kbd_dev Keyboard device structure (must be initialized).
 * @param buffer Data from the keyboard (i.e. the report).
 * @param actual_size Size of the data from keyboard (report size) in bytes.
 *
 * @sa usb_kbd_process_keycodes(), usb_hid_boot_keyboard_input_report(),
 *     usb_hid_parse_report().
 */
static void usb_kbd_process_data(usb_hid_dev_t *hid_dev, usb_kbd_t *kbd_dev,
                                 uint8_t *buffer, size_t actual_size)
{
        assert(hid_dev->report != NULL);
        assert(hid_dev != NULL);
        assert(kbd_dev != NULL);

        usb_log_debug("Calling usb_hid_parse_report() with "
            "buffer %s\n", usb_debug_str_buffer(buffer, actual_size, 0));
        
//      int rc = usb_hid_boot_keyboard_input_report(buffer, actual_size,
//          callbacks, kbd_dev);
        usb_hid_report_path_t *path = usb_hid_report_path();
        usb_hid_report_path_append_item(path, USB_HIDUT_PAGE_KEYBOARD, 0);
        //usb_hid_report_path_set_report_id(path, 0);

        uint8_t report_id;
        int rc = usb_hid_parse_report(hid_dev->report, buffer, actual_size, 
            &report_id);
        
        if (rc != EOK) {
                usb_log_warning("Error in usb_hid_parse_report():"
                    "%s\n", str_error(rc));
        }
        
        usb_hid_report_path_set_report_id (path, report_id);
        
        // fill in the currently pressed keys
        
        usb_hid_report_field_t *field = usb_hid_report_get_sibling(
            hid_dev->report, NULL, path, 
            USB_HID_PATH_COMPARE_END | USB_HID_PATH_COMPARE_USAGE_PAGE_ONLY, 
            USB_HID_REPORT_TYPE_INPUT);
        unsigned i = 0;
        
        while (field != NULL) {
                usb_log_debug2("FIELD (%p) - VALUE(%d) USAGE(%u)\n", 
                    field, field->value, field->usage);
                
                assert(i < kbd_dev->key_count);
//              if (i == kbd_dev->key_count) {
//                      break;
//              }
                
                // save the key usage
                /* TODO: maybe it's not good to save value, nor usage
                 *       as the value may be e.g. 1 for LEDs and usage may be
                 *       value of the LED. On the other hand, in case of normal
                 *       keys, the usage is more important and we must check
                 *       that. One possible solution: distinguish between those
                 *       two parts of the Report somehow.
                 */
                if (field->value != 0) {
                        kbd_dev->keys[i] = field->usage;
                }
                else {
                        kbd_dev->keys[i] = 0;
                }
                usb_log_debug2("Saved %u. key usage %d\n", i, kbd_dev->keys[i]);
                
                ++i;
                field = usb_hid_report_get_sibling(hid_dev->report, field, path, 
                    USB_HID_PATH_COMPARE_END 
                    | USB_HID_PATH_COMPARE_USAGE_PAGE_ONLY, 
                    USB_HID_REPORT_TYPE_INPUT);
        }
        
        usb_hid_report_path_free(path);
        
        usb_kbd_check_key_changes(hid_dev, kbd_dev);
}

/*----------------------------------------------------------------------------*/
/* HID/KBD structure manipulation                                             */
/*----------------------------------------------------------------------------*/

static void usb_kbd_mark_unusable(usb_kbd_t *kbd_dev)
{
        kbd_dev->initialized = USB_KBD_STATUS_TO_DESTROY;
}

/*----------------------------------------------------------------------------*/

/**
 * Creates a new USB/HID keyboard structure.
 *
 * The structure returned by this function is not initialized. Use 
 * usb_kbd_init() to initialize it prior to polling.
 *
 * @return New uninitialized structure for representing a USB/HID keyboard or
 *         NULL if not successful (memory error).
 */
static usb_kbd_t *usb_kbd_new(void)
{
        usb_kbd_t *kbd_dev = 
            (usb_kbd_t *)calloc(1, sizeof(usb_kbd_t));

        if (kbd_dev == NULL) {
                usb_log_fatal("No memory!\n");
                return NULL;
        }
        
        kbd_dev->console_phone = -1;
        kbd_dev->initialized = USB_KBD_STATUS_UNINITIALIZED;
        
        return kbd_dev;
}

/*----------------------------------------------------------------------------*/

static int usb_kbd_create_function(usb_hid_dev_t *hid_dev, usb_kbd_t *kbd_dev)
{
        assert(hid_dev != NULL);
        assert(hid_dev->usb_dev != NULL);
        assert(kbd_dev != NULL);
        
        /* Create the function exposed under /dev/devices. */
        usb_log_debug("Creating DDF function %s...\n", HID_KBD_FUN_NAME);
        ddf_fun_t *fun = ddf_fun_create(hid_dev->usb_dev->ddf_dev, fun_exposed, 
            HID_KBD_FUN_NAME);
        if (fun == NULL) {
                usb_log_error("Could not create DDF function node.\n");
                return ENOMEM;
        }
        
        /*
         * Store the initialized HID device and HID ops
         * to the DDF function.
         */
        fun->ops = &kbd_dev->ops;
        fun->driver_data = kbd_dev;

        int rc = ddf_fun_bind(fun);
        if (rc != EOK) {
                usb_log_error("Could not bind DDF function: %s.\n",
                    str_error(rc));
                ddf_fun_destroy(fun);
                return rc;
        }
        
        usb_log_debug("Adding DDF function to class %s...\n", 
            HID_KBD_CLASS_NAME);
        rc = ddf_fun_add_to_class(fun, HID_KBD_CLASS_NAME);
        if (rc != EOK) {
                usb_log_error(
                    "Could not add DDF function to class %s: %s.\n",
                    HID_KBD_CLASS_NAME, str_error(rc));
                ddf_fun_destroy(fun);
                return rc;
        }
        
        return EOK;
}

/*----------------------------------------------------------------------------*/
/* API functions                                                              */
/*----------------------------------------------------------------------------*/
/**
 * Initialization of the USB/HID keyboard structure.
 *
 * This functions initializes required structures from the device's descriptors.
 *
 * During initialization, the keyboard is switched into boot protocol, the idle
 * rate is set to 0 (infinity), resulting in the keyboard only reporting event
 * when a key is pressed or released. Finally, the LED lights are turned on 
 * according to the default setup of lock keys.
 *
 * @note By default, the keyboards is initialized with Num Lock turned on and 
 *       other locks turned off.
 *
 * @param kbd_dev Keyboard device structure to be initialized.
 * @param dev DDF device structure of the keyboard.
 *
 * @retval EOK if successful.
 * @retval EINVAL if some parameter is not given.
 * @return Other value inherited from function usbhid_dev_init().
 */
int usb_kbd_init(usb_hid_dev_t *hid_dev, void **data)
{
        usb_log_debug("Initializing HID/KBD structure...\n");
        
        if (hid_dev == NULL) {
                usb_log_error("Failed to init keyboard structure: no structure"
                    " given.\n");
                return EINVAL;
        }
        
        usb_kbd_t *kbd_dev = usb_kbd_new();
        if (kbd_dev == NULL) {
                usb_log_error("Error while creating USB/HID KBD device "
                    "structure.\n");
                return ENOMEM;  // TODO: some other code??
        }
        
        /*
         * TODO: make more general
         */
        usb_hid_report_path_t *path = usb_hid_report_path();
        usb_hid_report_path_append_item(path, USB_HIDUT_PAGE_KEYBOARD, 0);
        
        usb_hid_report_path_set_report_id(path, 0);
        
        kbd_dev->key_count = usb_hid_report_size(
            hid_dev->report, 0, USB_HID_REPORT_TYPE_INPUT); 
        usb_hid_report_path_free(path);
        
        usb_log_debug("Size of the input report: %zu\n", kbd_dev->key_count);
        
        kbd_dev->keys = (int32_t *)calloc(kbd_dev->key_count, sizeof(int32_t));
        
        if (kbd_dev->keys == NULL) {
                usb_log_fatal("No memory!\n");
                free(kbd_dev);
                return ENOMEM;
        }
        
        kbd_dev->keys_old = 
                (int32_t *)calloc(kbd_dev->key_count, sizeof(int32_t));
        
        if (kbd_dev->keys_old == NULL) {
                usb_log_fatal("No memory!\n");
                free(kbd_dev->keys);
                free(kbd_dev);
                return ENOMEM;
        }
        
        /*
         * Output report
         */
        kbd_dev->output_size = 0;
        kbd_dev->output_buffer = usb_hid_report_output(hid_dev->report, 
            &kbd_dev->output_size, 0);
        if (kbd_dev->output_buffer == NULL) {
                usb_log_warning("Error creating output report buffer.\n");
                free(kbd_dev->keys);
                return ENOMEM;  /* TODO: other error code */
        }
        
        usb_log_debug("Output buffer size: %zu\n", kbd_dev->output_size);
        
        kbd_dev->led_path = usb_hid_report_path();
        usb_hid_report_path_append_item(
            kbd_dev->led_path, USB_HIDUT_PAGE_LED, 0);
        
        kbd_dev->led_output_size = usb_hid_report_size(hid_dev->report, 
            0, USB_HID_REPORT_TYPE_OUTPUT);
        
        usb_log_debug("Output report size (in items): %zu\n", 
            kbd_dev->led_output_size);
        
        kbd_dev->led_data = (int32_t *)calloc(
            kbd_dev->led_output_size, sizeof(int32_t));
        
        if (kbd_dev->led_data == NULL) {
                usb_log_warning("Error creating buffer for LED output report."
                    "\n");
                free(kbd_dev->keys);
                usb_hid_report_output_free(kbd_dev->output_buffer);
                free(kbd_dev);
                return ENOMEM;
        }
        
        /*
         * Modifiers and locks
         */     
        kbd_dev->modifiers = 0;
        kbd_dev->mods = DEFAULT_ACTIVE_MODS;
        kbd_dev->lock_keys = 0;
        
        /*
         * Autorepeat
         */     
        kbd_dev->repeat.key_new = 0;
        kbd_dev->repeat.key_repeated = 0;
        kbd_dev->repeat.delay_before = DEFAULT_DELAY_BEFORE_FIRST_REPEAT;
        kbd_dev->repeat.delay_between = DEFAULT_REPEAT_DELAY;
        
        kbd_dev->repeat_mtx = (fibril_mutex_t *)(
            malloc(sizeof(fibril_mutex_t)));
        if (kbd_dev->repeat_mtx == NULL) {
                usb_log_fatal("No memory!\n");
                free(kbd_dev->keys);
                usb_hid_report_output_free(kbd_dev->output_buffer);
                free(kbd_dev);
                return ENOMEM;
        }
        
        fibril_mutex_initialize(kbd_dev->repeat_mtx);
        
        // save the KBD device structure into the HID device structure
        //hid_dev->data = kbd_dev;
        *data = kbd_dev;
        
        // set handler for incoming calls
        kbd_dev->ops.default_handler = default_connection_handler;
        
        /*
         * Set LEDs according to initial setup.
         * Set Idle rate
         */
        usb_kbd_set_led(hid_dev, kbd_dev);
        
        usbhid_req_set_idle(&hid_dev->usb_dev->ctrl_pipe, 
            hid_dev->usb_dev->interface_no, IDLE_RATE);
        
        /*
         * Create new fibril for auto-repeat
         */
        fid_t fid = fibril_create(usb_kbd_repeat_fibril, kbd_dev);
        if (fid == 0) {
                usb_log_error("Failed to start fibril for KBD auto-repeat");
                return ENOMEM;
        }
        fibril_add_ready(fid);
        
        kbd_dev->initialized = USB_KBD_STATUS_INITIALIZED;
        usb_log_debug("HID/KBD device structure initialized.\n");
        
        usb_log_debug("Creating KBD function...\n");
        int rc = usb_kbd_create_function(hid_dev, kbd_dev);
        if (rc != EOK) {
                usb_kbd_free(&kbd_dev);
                return rc;
        }
        
        return EOK;
}

/*----------------------------------------------------------------------------*/

bool usb_kbd_polling_callback(usb_hid_dev_t *hid_dev, void *data, 
     uint8_t *buffer, size_t buffer_size)
{
        if (hid_dev == NULL || buffer == NULL || data == NULL) {
                // do not continue polling (???)
                return false;
        }
        
        usb_kbd_t *kbd_dev = (usb_kbd_t *)data;
        assert(kbd_dev != NULL);
        
        // TODO: add return value from this function
        usb_kbd_process_data(hid_dev, kbd_dev, buffer, buffer_size);
        
        return true;
}

/*----------------------------------------------------------------------------*/

int usb_kbd_is_initialized(const usb_kbd_t *kbd_dev)
{
        return (kbd_dev->initialized == USB_KBD_STATUS_INITIALIZED);
}

/*----------------------------------------------------------------------------*/

int usb_kbd_is_ready_to_destroy(const usb_kbd_t *kbd_dev)
{
        return (kbd_dev->initialized == USB_KBD_STATUS_TO_DESTROY);
}

/*----------------------------------------------------------------------------*/
/**
 * Properly destroys the USB/HID keyboard structure.
 *
 * @param kbd_dev Pointer to the structure to be destroyed.
 */
void usb_kbd_free(usb_kbd_t **kbd_dev)
{
        if (kbd_dev == NULL || *kbd_dev == NULL) {
                return;
        }
        
        // hangup phone to the console
        async_hangup((*kbd_dev)->console_phone);
        
        if ((*kbd_dev)->repeat_mtx != NULL) {
                /* TODO: replace by some check and wait */
                assert(!fibril_mutex_is_locked((*kbd_dev)->repeat_mtx));
                free((*kbd_dev)->repeat_mtx);
        }
        
        // free all buffers
        if ((*kbd_dev)->keys != NULL) {
                free((*kbd_dev)->keys);
        }
        if ((*kbd_dev)->keys_old != NULL) {
                free((*kbd_dev)->keys_old);
        }
        if ((*kbd_dev)->led_data != NULL) {
                free((*kbd_dev)->led_data);
        }
        if ((*kbd_dev)->led_path != NULL) {
                usb_hid_report_path_free((*kbd_dev)->led_path);
        }
        if ((*kbd_dev)->output_buffer != NULL) {
                usb_hid_report_output_free((*kbd_dev)->output_buffer);
        }

        free(*kbd_dev);
        *kbd_dev = NULL;
}

/*----------------------------------------------------------------------------*/

void usb_kbd_deinit(usb_hid_dev_t *hid_dev, void *data)
{
        if (hid_dev == NULL) {
                return;
        }
        
        if (data != NULL) {
                usb_kbd_t *kbd_dev = (usb_kbd_t *)data;
                if (usb_kbd_is_initialized(kbd_dev)) {
                        usb_kbd_mark_unusable(kbd_dev);
                } else {
                        usb_kbd_free(&kbd_dev);
                }
        }
}

/*----------------------------------------------------------------------------*/

int usb_kbd_set_boot_protocol(usb_hid_dev_t *hid_dev)
{
        int rc = usb_hid_parse_report_descriptor(hid_dev->report, 
            USB_KBD_BOOT_REPORT_DESCRIPTOR, 
            USB_KBD_BOOT_REPORT_DESCRIPTOR_SIZE);
        
        if (rc != EOK) {
                usb_log_error("Failed to parse boot report descriptor: %s\n",
                    str_error(rc));
                return rc;
        }
        
        rc = usbhid_req_set_protocol(&hid_dev->usb_dev->ctrl_pipe, 
            hid_dev->usb_dev->interface_no, USB_HID_PROTOCOL_BOOT);
        
        if (rc != EOK) {
                usb_log_warning("Failed to set boot protocol to the device: "
                    "%s\n", str_error(rc));
                return rc;
        }
        
        return EOK;
}

/**
 * @}
 */