* Reduce leaking of TX buffers

* Found the problem that when switching between receiving and sending tc_cdiv would most of the time not generate an SSC_CLOCK for approx. 5ms: The issue is that after setting the divisor (which 
stored in RC) CV might be greater than RC. Thus no compare will happen until CV overflows (at 0xffff carrier cycles) and therefore the clock will appear to be stopped for that time. A good fix would 
have been TC_CV = TC_CV % TC_RC but unfortunately TC_CV is read-only. Instead use SWTRG to reset TC_CV to zero and then try to use the phase-shift code to have the phase stay correct.
* Measured the transmit start delay that is introduced by the SSC TF emulation through FIQ and adjusted ISO14443A_FDT accordingly


git-svn-id: https://svn.openpcd.org:2342/trunk@366 6dc7ffe9-61d6-0310-9af1-9938baff3ed1

1 files changed, 11 insertions, 1 deletions

diff --git a/openpicc/application/ssc_picc.c b/openpicc/application/ssc_picc.c
index a5f1075..02d87d1 100644
--- a/openpicc/application/ssc_picc.c
+++ b/openpicc/application/ssc_picc.c
@@ -205,6 +205,7 @@ void ssc_tx_start(ssc_dma_tx_buffer_t *buf)
 	ssc->SSC_TCMR = 0x01 | AT91C_SSC_CKO_NONE | start_cond;
 	
 	AT91F_PDC_SetTx(tx_pdc, buf->data, num_data);
+	buf->state = PENDING;
 
 #ifdef TEST_WHETHER_NOT_ENABLING_IT_HELPS
 	AT91F_SSC_EnableIt(ssc, AT91C_SSC_TXSYN | AT91C_SSC_ENDTX | AT91C_SSC_TXBUFE);
@@ -227,6 +228,7 @@ void ssc_tx_start(ssc_dma_tx_buffer_t *buf)
 #ifdef USE_SSC_TX_TF_WORKAROUND
 void ssc_tf_irq(u_int32_t pio) {
 	(void)pio;
+	if(!AT91F_PIO_IsInputSet(AT91C_BASE_PIOA, OPENPICC_SSC_TF)) return;
 	pio_irq_disable(OPENPICC_SSC_TF);
 	if(ssc_tx_pending) { /* Transmit has not yet been started by the FIQ */
 		AT91F_SSC_EnableTx(AT91C_BASE_SSC);
@@ -397,7 +399,15 @@ static void __ramfunc ssc_irq(void)
 		DEBUGP("CP0 ");
 	
 	if (ssc_sr & AT91C_SSC_TXSYN)
-		usb_print_string_f("TXSYN ", 0);
+		DEBUGP("TXSYN ");
+	
+	if(ssc_sr & AT91C_SSC_ENDTX) {
+		if(ssc_tx_buffer.state == PENDING)
+			ssc_tx_buffer.state = FREE;
+	}
+
+	if(ssc_sr & AT91C_SSC_TXBUFE)
+		DEBUGP("TXBUFE ");
 	
 	if(irq_extension != NULL)
 		irq_extension(ssc_sr, ssc_state.mode, inbuf?inbuf->data:NULL);