/*
 * Copyright (c) 2010 Vojtech Horky
 * 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 libusb usb
 * @{
 */
/** @file
 * @brief USB Host Controller Driver (implementation).
 */
#include "hcd.h"
#include <devmap.h>
#include <stdlib.h>
#include <fcntl.h>
#include <vfs/vfs.h>
#include <errno.h>

/** Information about pending transaction on HC. */
typedef struct {
	/** Phone to host controller driver. */
	int phone;
	/** Data buffer. */
	void *buffer;
	/** Buffer size. */
	size_t size;
	/** Storage for actual number of bytes transferred. */
	size_t *size_transferred;
	/** Initial call replay data. */
	ipc_call_t reply;
	/** Initial call identifier. */
	aid_t request;
} transfer_info_t;

#define NAMESPACE "usb"

/** String representation for USB transfer type. */
const char * usb_str_transfer_type(usb_transfer_type_t t)
{
	switch (t) {
		case USB_TRANSFER_ISOCHRONOUS:
			return "isochronous";
		case USB_TRANSFER_INTERRUPT:
			return "interrupt";
		case USB_TRANSFER_CONTROL:
			return "control";
		case USB_TRANSFER_BULK:
			return "bulk";
		default:
			return "unknown";
	}
}

/** String representation of USB transaction outcome. */
const char * usb_str_transaction_outcome(usb_transaction_outcome_t o)
{
	switch (o) {
		case USB_OUTCOME_OK:
			return "ok";
		case USB_OUTCOME_CRCERROR:
			return "CRC error";
		case USB_OUTCOME_BABBLE:
			return "babble";
		default:
			return "unknown";
	}
}

/** Create necessary phones for communicating with HCD.
 * This function wraps following calls:
 * -# open <code>/dev/usb/<i>hcd_path</i></code> for reading
 * -# access phone of file opened in previous step
 * -# return the (outgoing) phone
 *
 * @warning This function is wrapper for several actions and therefore
 * it is not possible - in case of error - to determine at which point
 * error occurred.
 *
 * @param hcd_path HCD identification under devfs
 *     (without <code>/dev/usb/</code>).
 * @return Phone for communicating with HCD or error code from errno.h.
 */
int usb_hcd_connect(const char * hcd_path)
{
	char dev_path[DEVMAP_NAME_MAXLEN + 1];
	snprintf(dev_path, DEVMAP_NAME_MAXLEN,
	    "/dev/%s/%s", NAMESPACE, hcd_path);
	
	int fd = open(dev_path, O_RDONLY);
	if (fd < 0) {
		return fd;
	}
	
	int hcd_phone = fd_phone(fd);
	
	if (hcd_phone < 0) {
		return hcd_phone;
	}

	return hcd_phone;
}

/** Send data to HCD.
 *
 * @param phone Opened phone to HCD.
 * @param method Method used for calling.
 * @param target Target device.
 * @param buffer Data buffer (NULL to skip data transfer phase).
 * @param size Buffer size (must be zero when @p buffer is NULL).
 * @param handle Storage for transaction handle (cannot be NULL).
 * @return Error status.
 * @retval EINVAL Invalid parameter.
 * @retval ENOMEM Not enough memory to complete the operation.
 */
static int async_send_buffer(int phone, int method,
    usb_target_t target,
    void *buffer, size_t size,
    usb_handle_t *handle)
{
	if (phone < 0) {
		return EINVAL;
	}
	
	if ((buffer == NULL) && (size > 0)) {
		return EINVAL;
	}
	
	if (handle == NULL) {
		return EINVAL;
	}

	transfer_info_t *transfer
	    = (transfer_info_t *) malloc(sizeof(transfer_info_t));
	if (transfer == NULL) {
		return ENOMEM;
	}
	
	transfer->size_transferred = NULL;
	transfer->buffer = NULL;
	transfer->size = 0;
	transfer->phone = phone;

	int rc;
	
	transfer->request = async_send_3(phone,
	    method,
	    target.address, target.endpoint,
	    size,
	    &transfer->reply);
	
	if (size > 0) {
		rc = async_data_write_start(phone, buffer, size);
		if (rc != EOK) {
			async_wait_for(transfer->request, NULL);
			return rc;
		}
	}
	
	*handle = (usb_handle_t) transfer;
	
	return EOK;
}

/** Prepare data retrieval.
 *
 * @param phone Opened phone to HCD.
 * @param method Method used for calling.
 * @param target Target device.
 * @param buffer Buffer where to store retrieved data
 * 	(NULL to skip data transfer phase).
 * @param size Buffer size (must be zero when @p buffer is NULL).
 * @param actual_size Storage where actual number of bytes transferred will
 * 	be stored.
 * @param handle Storage for transaction handle (cannot be NULL).
 * @return Error status.
 * @retval EINVAL Invalid parameter.
 * @retval ENOMEM Not enough memory to complete the operation.
 */
static int async_recv_buffer(int phone, int method,
    usb_target_t target,
    void *buffer, size_t size, size_t *actual_size,
    usb_handle_t *handle)
{
	if (phone < 0) {
		return EINVAL;
	}
	
	if ((buffer == NULL) && (size > 0)) {
		return EINVAL;
	}
	
	if (handle == NULL) {
		return EINVAL;
	}

	transfer_info_t *transfer
	    = (transfer_info_t *) malloc(sizeof(transfer_info_t));
	if (transfer == NULL) {
		return ENOMEM;
	}
	
	transfer->size_transferred = actual_size;
	transfer->buffer = buffer;
	transfer->size = size;
	transfer->phone = phone;
	
	transfer->request = async_send_3(phone,
	    method,
	    target.address, target.endpoint,
	    size,
	    &transfer->reply);
	
	*handle = (usb_handle_t) transfer;
	
	return EOK;
}

/** Read buffer from HCD.
 *
 * @param phone Opened phone to HCD.
 * @param hash Buffer hash (obtained after completing IN transaction).
 * @param buffer Buffer where to store data data.
 * @param size Buffer size.
 * @param actual_size Storage where actual number of bytes transferred will
 * 	be stored.
 * @return Error status.
 */
static int read_buffer_in(int phone, ipcarg_t hash,
    void *buffer, size_t size, size_t *actual_size)
{
	ipc_call_t answer_data;
	ipcarg_t answer_rc;
	aid_t req;
	int rc;
	
	req = async_send_1(phone,
	    IPC_M_USB_HCD_GET_BUFFER_ASYNC,
	    hash,
	    &answer_data);
	
	rc = async_data_read_start(phone, buffer, size);
	if (rc != EOK) {
		async_wait_for(req, NULL);
		return EINVAL;
	}
	
	async_wait_for(req, &answer_rc);
	rc = (int)answer_rc;
	
	if (rc != EOK) {
		return rc;
	}
	
	*actual_size = IPC_GET_ARG1(answer_data);
	
	return EOK;
}

/** Blocks caller until given USB transaction is finished.
 * After the transaction is finished, the user can access all output data
 * given to initial call function.
 *
 * @param handle Transaction handle.
 * @return Error status.
 * @retval EOK No error.
 * @retval EBADMEM Invalid handle.
 * @retval ENOENT Data buffer associated with transaction does not exist.
 */
int usb_hcd_async_wait_for(usb_handle_t handle)
{
	if (handle == 0) {
		return EBADMEM;
	}
	
	int rc = EOK;
	
	transfer_info_t *transfer = (transfer_info_t *) handle;
	
	ipcarg_t answer_rc;
	async_wait_for(transfer->request, &answer_rc);
	
	if (answer_rc != EOK) {
		rc = (int) answer_rc;
		goto leave;
	}
	
	/*
	 * If the buffer is not NULL, we must accept some data.
	 */
	if ((transfer->buffer != NULL) && (transfer->size > 0)) {
		/*
		 * The buffer hash identifies the data on the server
		 * side.
		 * We will use it when actually reading-in the data.
		 */
		ipcarg_t buffer_hash = IPC_GET_ARG1(transfer->reply);
		if (buffer_hash == 0) {
			rc = ENOENT;
			goto leave;
		}
		
		size_t actual_size;
		rc = read_buffer_in(transfer->phone, buffer_hash,
		    transfer->buffer, transfer->size, &actual_size);
		
		if (rc != EOK) {
			goto leave;
		}
		
		if (transfer->size_transferred) {
			*(transfer->size_transferred) = actual_size;
		}
	}
	
leave:
	free(transfer);
	
	return rc;
}

/** Send interrupt data to device. */
int usb_hcd_async_transfer_interrupt_out(int hcd_phone,
    usb_target_t target,
    void *buffer, size_t size,
    usb_handle_t *handle)
{
	return async_send_buffer(hcd_phone,
	    IPC_M_USB_HCD_INTERRUPT_OUT_ASYNC,
	    target,
	    buffer, size,
	    handle);
}

/** Request interrupt data from device. */
int usb_hcd_async_transfer_interrupt_in(int hcd_phone,
    usb_target_t target,
    void *buffer, size_t size, size_t *actual_size,
    usb_handle_t *handle)
{
	return async_recv_buffer(hcd_phone,
	    IPC_M_USB_HCD_INTERRUPT_IN_ASYNC,
	    target,
	    buffer, size, actual_size,
	    handle);
}

/** Start WRITE control transfer. */
int usb_hcd_async_transfer_control_write_setup(int hcd_phone,
    usb_target_t target,
    void *buffer, size_t size,
    usb_handle_t *handle)
{
	return async_send_buffer(hcd_phone,
	    IPC_M_USB_HCD_CONTROL_WRITE_SETUP_ASYNC,
	    target,
	    buffer, size,
	    handle);
}

/** Send data during WRITE control transfer. */
int usb_hcd_async_transfer_control_write_data(int hcd_phone,
    usb_target_t target,
    void *buffer, size_t size,
    usb_handle_t *handle)
{
	return async_send_buffer(hcd_phone,
	    IPC_M_USB_HCD_CONTROL_WRITE_DATA_ASYNC,
	    target,
	    buffer, size,
	    handle);
}

/** Terminate WRITE control transfer. */
int usb_hcd_async_transfer_control_write_status(int hcd_phone,
    usb_target_t target,
    usb_handle_t *handle)
{
	return async_recv_buffer(hcd_phone,
	    IPC_M_USB_HCD_CONTROL_WRITE_STATUS_ASYNC,
	    target,
	    NULL, 0, NULL,
	    handle);
}

/** Start READ control transfer. */
int usb_hcd_async_transfer_control_read_setup(int hcd_phone,
    usb_target_t target,
    void *buffer, size_t size,
    usb_handle_t *handle)
{
	return async_send_buffer(hcd_phone,
	    IPC_M_USB_HCD_CONTROL_READ_SETUP_ASYNC,
	    target,
	    buffer, size,
	    handle);
}

/** Request data during READ control transfer. */
int usb_hcd_async_transfer_control_read_data(int hcd_phone,
    usb_target_t target,
    void *buffer, size_t size, size_t *actual_size,
    usb_handle_t *handle)
{
	return async_recv_buffer(hcd_phone,
	    IPC_M_USB_HCD_CONTROL_READ_DATA_ASYNC,
	    target,
	    buffer, size, actual_size,
	    handle);
}

/** Terminate READ control transfer. */
int usb_hcd_async_transfer_control_read_status(int hcd_phone,
    usb_target_t target,
    usb_handle_t *handle)
{
	return async_send_buffer(hcd_phone,
	    IPC_M_USB_HCD_CONTROL_READ_STATUS_ASYNC,
	    target,
	    NULL, 0,
	    handle);
}

/**
 * @}
 */