1 files changed, 58 insertions, 0 deletions
diff --git a/firmware/src/picc/poti.c b/firmware/src/picc/poti.c
new file mode 100644
index 0000000..2cc8e5c
--- /dev/null
+++ b/firmware/src/picc/poti.c
@@ -0,0 +1,58 @@
+/* SPI Potentiometer AD 7367 Driver for OpenPICC
+ * (C) by Harald Welte <hwelte@hmw-consulting.de>
+ */
+
+#include <sys/types.h>
+#include <lib_AT91SAM7.h>
+#include "../openpcd.h"
+
+static const AT91PS_SPI spi = AT91C_BASE_SPI;
+
+void poti_comp_carr(u_int8_t position)
+{
+	volatile int i;
+
+	while (!(spi->SPI_SR & AT91C_SPI_TDRE)) { }
+	AT91F_PIO_ClearOutput(AT91C_BASE_PIOA, OPENPICC_PIO_SS2_DT_THRESH);
+	//for (i = 0; i < 0xff; i++) { }
+	/* shift one left, since it is a seven-bit value written as 8 bit xfer */
+	spi->SPI_TDR = position & 0x7f;
+	while (!(spi->SPI_SR & AT91C_SPI_TDRE)) { }
+	for (i = 0; i < 0xff; i++) { }
+	AT91F_PIO_SetOutput(AT91C_BASE_PIOA, OPENPICC_PIO_SS2_DT_THRESH);
+}
+
+void poti_reset(void)
+{
+	volatile int i;
+	AT91F_PIO_ClearOutput(AT91C_BASE_PIOA, OPENPICC_PIO_nSLAVE_RESET);
+	for (i = 0; i < 0xff; i++) { }
+	AT91F_PIO_SetOutput(AT91C_BASE_PIOA, OPENPICC_PIO_nSLAVE_RESET);
+}
+
+void poti_init(void)
+{
+	AT91F_SPI_CfgPMC();
+	AT91F_PIO_CfgPeriph(AT91C_BASE_PIOA, 
+			    AT91C_PA13_MOSI | AT91C_PA14_SPCK, 0);
+
+	AT91F_PIO_CfgOutput(AT91C_BASE_PIOA, OPENPICC_PIO_SS2_DT_THRESH);
+	AT91F_PIO_SetOutput(AT91C_BASE_PIOA, OPENPICC_PIO_SS2_DT_THRESH);
+
+	AT91F_PIO_CfgOutput(AT91C_BASE_PIOA, OPENPICC_PIO_nSLAVE_RESET);
+	poti_reset();
+
+#if 0
+	AT91F_AIC_ConfigureIt(AT91C_BASE_AIC, AT91C_ID_SPI,
+			      OPENPCD_IRQ_PRIO_SPI,
+			      AT91C_AIC_SRCTYPE_INT_HIGH_LEVEL, &spi_irq);
+	AT91G_AIC_EnableIt(AT9C_BASE_AIC, AT91C_ID_SPI);
+#endif
+	AT91F_SPI_CfgMode(spi, AT91C_SPI_MSTR | 
+			  AT91C_SPI_PS_FIXED | AT91C_SPI_MODFDIS);
+	/* CPOL = 0, NCPHA = 1, CSAAT = 0, BITS = 0000, SCBR = 13 (3.69MHz),
+	 * DLYBS = 6 (125nS), DLYBCT = 0 */
+	AT91F_SPI_CfgCs(spi, 0, AT91C_SPI_BITS_8 | AT91C_SPI_NCPHA |
+			(13 << 8) | (6 << 16));
+	AT91F_SPI_Enable(spi);
+}