+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0+
-/*
- * (C) Copyright 2002
- * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com.
- *
- * Influenced by code from:
- * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
- */
-
-#include <common.h>
-#include <spi.h>
-
-#include <malloc.h>
-
-/*-----------------------------------------------------------------------
- * Definitions
- */
-
-#ifdef DEBUG_SPI
-#define PRINTD(fmt,args...) printf (fmt ,##args)
-#else
-#define PRINTD(fmt,args...)
-#endif
-
-struct soft_spi_slave {
- struct spi_slave slave;
- unsigned int mode;
-};
-
-static inline struct soft_spi_slave *to_soft_spi(struct spi_slave *slave)
-{
- return container_of(slave, struct soft_spi_slave, slave);
-}
-
-/*=====================================================================*/
-/* Public Functions */
-/*=====================================================================*/
-
-struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
- unsigned int max_hz, unsigned int mode)
-{
- struct soft_spi_slave *ss;
-
- if (!spi_cs_is_valid(bus, cs))
- return NULL;
-
- ss = spi_alloc_slave(struct soft_spi_slave, bus, cs);
- if (!ss)
- return NULL;
-
- ss->mode = mode;
-
- /* TODO: Use max_hz to limit the SCK rate */
-
- return &ss->slave;
-}
-
-void spi_free_slave(struct spi_slave *slave)
-{
- struct soft_spi_slave *ss = to_soft_spi(slave);
-
- free(ss);
-}
-
-int spi_claim_bus(struct spi_slave *slave)
-{
-#ifdef CONFIG_SYS_IMMR
- volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
-#endif
- struct soft_spi_slave *ss = to_soft_spi(slave);
-
- /*
- * Make sure the SPI clock is in idle state as defined for
- * this slave.
- */
- if (ss->mode & SPI_CPOL)
- SPI_SCL(1);
- else
- SPI_SCL(0);
-
- return 0;
-}
-
-void spi_release_bus(struct spi_slave *slave)
-{
- /* Nothing to do */
-}
-
-/*-----------------------------------------------------------------------
- * SPI transfer
- *
- * This writes "bitlen" bits out the SPI MOSI port and simultaneously clocks
- * "bitlen" bits in the SPI MISO port. That's just the way SPI works.
- *
- * The source of the outgoing bits is the "dout" parameter and the
- * destination of the input bits is the "din" parameter. Note that "dout"
- * and "din" can point to the same memory location, in which case the
- * input data overwrites the output data (since both are buffered by
- * temporary variables, this is OK).
- */
-int spi_xfer(struct spi_slave *slave, unsigned int bitlen,
- const void *dout, void *din, unsigned long flags)
-{
-#ifdef CONFIG_SYS_IMMR
- volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
-#endif
- struct soft_spi_slave *ss = to_soft_spi(slave);
- uchar tmpdin = 0;
- uchar tmpdout = 0;
- const u8 *txd = dout;
- u8 *rxd = din;
- int cpol = ss->mode & SPI_CPOL;
- int cpha = ss->mode & SPI_CPHA;
- unsigned int j;
-
- PRINTD("spi_xfer: slave %u:%u dout %08X din %08X bitlen %u\n",
- slave->bus, slave->cs, *(uint *)txd, *(uint *)rxd, bitlen);
-
- if (flags & SPI_XFER_BEGIN)
- spi_cs_activate(slave);
-
- for(j = 0; j < bitlen; j++) {
- /*
- * Check if it is time to work on a new byte.
- */
- if ((j % 8) == 0) {
- if (txd)
- tmpdout = *txd++;
- else
- tmpdout = 0;
- if(j != 0) {
- if (rxd)
- *rxd++ = tmpdin;
- }
- tmpdin = 0;
- }
-
- if (!cpha)
- SPI_SCL(!cpol);
- SPI_SDA(tmpdout & 0x80);
- SPI_DELAY;
- if (cpha)
- SPI_SCL(!cpol);
- else
- SPI_SCL(cpol);
- tmpdin <<= 1;
- tmpdin |= SPI_READ;
- tmpdout <<= 1;
- SPI_DELAY;
- if (cpha)
- SPI_SCL(cpol);
- }
- /*
- * If the number of bits isn't a multiple of 8, shift the last
- * bits over to left-justify them. Then store the last byte
- * read in.
- */
- if (rxd) {
- if ((bitlen % 8) != 0)
- tmpdin <<= 8 - (bitlen % 8);
- *rxd++ = tmpdin;
- }
-
- if (flags & SPI_XFER_END)
- spi_cs_deactivate(slave);
-
- return(0);
-}