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/* 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;
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_init(void)
{
AT91F_SPI_CfgPMC();
AT91F_PIO_CfgPeriph(AT91C_BASE_PIOA, AT91C_PA12_MISO |
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);
#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 = 12 (4MHz),
* DLYBS = 0, DLYBCT = 0 */
AT91F_SPI_CfgCs(spi, 0, AT91C_SPI_BITS_8 | AT91C_SPI_NCPHA | (24<<8));
AT91F_SPI_Enable(spi);
}
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