/* SPI Potentiometer AD 7367 Driver for OpenPICC * (C) 2006 by Harald Welte <hwelte@hmw-consulting.de> * * 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; either version 2 of the License, or * (at your option) any later version. * * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA * */ #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); /* 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); }