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/***************************************************************

 *

 * OpenPICC - ISO 14443 Layer 2 Type A PICC transceiver code

 * Manages receiving, sending and parts of framing

 * 

 * This does not fully implement layer 2 in that it won't 

 * automatically call the Miller decoder or Manchester encoder

 * for you. Instead you'll be given ssc rx buffer pointers and

 * are expected to hand in ssc tx buffer pointers. You've got

 * to call iso14443a_manchester and iso14443a_miller yourself.

 * The reason is that this makes it possible for the layer 3

 * implementation to work on raw samples without en/de-coding

 * time to enable fast responses during anticollision.

 *

 * Copyright 2008 Henryk Plötz <henryk@ploetzli.ch>

 *

 ***************************************************************

    This program is free software; you can redistribute it and/or modify

    it under the terms of the GNU General Public License as published by

    the Free Software Foundation; version 2.

    This program is distributed in the hope that it will be useful,

    but WITHOUT ANY WARRANTY; without even the implied warranty of

    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License along

    with this program; if not, write to the Free Software Foundation, Inc.,

    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

*/

#include <FreeRTOS.h>

#include <board.h>

#include <task.h>

#include <errno.h>

#include "openpicc.h"

#include "iso14443_layer2a.h"

#include "tc_fdt.h"

#include "tc_cdiv.h"

#include "tc_cdiv_sync.h"

#include "usb_print.h"

#define PRINT_DEBUG 0

static u_int8_t fast_receive;

static u_int8_t rx_pending=0;

static iso14443_receive_callback_t callback=NULL;

#ifdef FOUR_TIMES_OVERSAMPLING

#define RX_DIVIDER 32

#else

#define RX_DIVIDER 64

#endif

		return -EALREADY;

	}

	rx_pending=1;

	callback=_callback;

			callback=NULL;

		}

		portENTER_CRITICAL();

			portENTER_CRITICAL();

		}

		callback=NULL;

	 * a frame start was received right before the timeout for this function 

	 * expired. In the future one might want to replace this with some safer code

	 * (hmm, maybe check TC2_CV?) but for now it's an essential safeguard to prevent

	 * a hung receiver when no proper frame end is signalled to iso14443_ssc_callback

	 * and therefore the callback never resets the flipflop */

	if(!tx_pending) {

		if(AT91F_PIO_IsInputSet(AT91C_BASE_PIOA, OPENPICC_PIO_FRAME)) tc_cdiv_sync_reset();

	}

	rx_pending=0;

	callback=NULL;

}

{

	if(tx_pending) 

		return -EBUSY;

	tx_pending = 1;

	/* Immediately set up FDT and clock */

	tc_fdt_set(fdt);

	//tc_cdiv_set_divider(8); // FIXME Magic hardcoded number

	if(!async) {

		/* FIXME Implement */

		(void)timeout;

		tx_pending = 0;

		return -EINVAL;

	}

	int ret = ssc_send(ssc, buffer);

	if(ret < 0) {

		tx_pending = 0;

		return ret;

	}

	if(!async) {

		/* FIXME Wait for completion, timeout or abort */

	}

	return 0;

}

{

	int ret = 0;

	taskENTER_CRITICAL();

	ret = ssc_send_abort(ssc);

	tx_pending = 0;

	taskEXIT_CRITICAL();

	return ret;

}

{

	(void)timeout;

	return 0;

}

u_int8_t iso14443_set_fast_receive(u_int8_t enable_fast_receive)

{

	u_int8_t old_value = fast_receive;

	fast_receive = enable_fast_receive;

	return old_value;

}

u_int8_t iso14443_get_fast_receive(void)

{

	return fast_receive;

}

		// We'll keep the divider at 8

		tc_cdiv_set_divider(8); // FIXME Magic hardcoded number

	}

		int *end_asserted = data, i=0;

		for(i=0; i<96000; i++) 

			if(*AT91C_TC2_CV > 2*128) { // FIXME magic number

				*end_asserted = 1;

				if(PRINT_DEBUG) usb_print_string_f("^", 0); // DEBUG OUTPUT

				break;

			}

		return;

	}

	}

		ssc_dma_rx_buffer_t *buffer = data;

		if(callback != NULL)

			|| reason == SSC_CALLBACK_TX_FRAME_ENDED ) {

		 * and switching clocks messes up the Tx timing, so we do a */

		//tc_cdiv_set_divider(RX_DIVIDER);

		DumpStringToUSB("["); DumpUIntToUSB(reason); DumpStringToUSB("]");

		usb_print_set_default_flush(old);

#endif

}

		iso14443_frame *frame = data;

		if(callback != NULL)

			callback(NULL, frame, 1);

	}

	if( (reason == TC_RECV_CALLBACK_RX_FRAME_ENDED && !tx_pending) ||

			reason == TC_RECV_CALLBACK_SETUP ) {

		/* For T/C Rx we set the clock to */

		tc_fdt_set(0xff00);

		//tc_cdiv_set_divider(RX_DIVIDER);

	}

{

	pll_init();

	tc_cdiv_init();

	tc_fdt_init();

	tc_cdiv_sync_enable();

	iso14443_set_fast_receive(enable_fast_receive);

		return -EIO;

	if(OPENPICC->features.clock_switching) {

		clock_switch(CLOCK_SELECT_CARRIER);

		pauses_count = 0;

	} else {

		if(OPENPICC->default_clock == CLOCK_SELECT_CARRIER) {

			pauses_count = 0;

		} else {

			return -ENOTSUP;

		}

	}

	if(tc_recv_init(&th, pauses_count, iso14443_tc_recv_callback) < 0) {

		return -EIO;

	}

}