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author | Markus Klotzbuecher <mk@denx.de> | 2008-07-10 10:26:07 +0200 |
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committer | Markus Klotzbuecher <mk@denx.de> | 2008-07-10 10:26:07 +0200 |
commit | 794a5924972fc8073616e98a2668da4a5f9aea90 (patch) | |
tree | dd0db39b3e183b5bcb0300d5377d7a0d5ac5fd0c /common/soft_spi.c | |
parent | f2aeecc320f5b181b30effcaa67683aec8d5a843 (diff) | |
parent | 4188f0491886b3b486164e819c0a83fdb97efd7d (diff) | |
download | u-boot-imx-794a5924972fc8073616e98a2668da4a5f9aea90.zip u-boot-imx-794a5924972fc8073616e98a2668da4a5f9aea90.tar.gz u-boot-imx-794a5924972fc8073616e98a2668da4a5f9aea90.tar.bz2 |
Merge branch 'master' of git://www.denx.de/git/u-boot
Diffstat (limited to 'common/soft_spi.c')
-rw-r--r-- | common/soft_spi.c | 124 |
1 files changed, 93 insertions, 31 deletions
diff --git a/common/soft_spi.c b/common/soft_spi.c index e425061..c131650 100644 --- a/common/soft_spi.c +++ b/common/soft_spi.c @@ -29,6 +29,8 @@ #if defined(CONFIG_SOFT_SPI) +#include <malloc.h> + /*----------------------------------------------------------------------- * Definitions */ @@ -39,6 +41,15 @@ #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 */ @@ -56,6 +67,57 @@ void spi_init (void) #endif } +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 = malloc(sizeof(struct soft_spi_slave)); + if (!ss) + return NULL; + + ss->slave.bus = bus; + ss->slave.cs = cs; + 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 CFG_IMMR + volatile immap_t *immr = (immap_t *)CFG_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 @@ -68,50 +130,54 @@ void spi_init (void) * 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). - * - * If the chipsel() function is not NULL, it is called with a parameter - * of '1' (chip select active) at the start of the transfer and again with - * a parameter of '0' at the end of the transfer. - * - * If the chipsel() function _is_ NULL, it the responsibility of the - * caller to make the appropriate chip select active before calling - * spi_xfer() and making it inactive after spi_xfer() returns. */ -int spi_xfer(spi_chipsel_type chipsel, int bitlen, uchar *dout, uchar *din) +int spi_xfer(struct spi_slave *slave, unsigned int bitlen, + const void *dout, void *din, unsigned long flags) { #ifdef CFG_IMMR volatile immap_t *immr = (immap_t *)CFG_IMMR; #endif - uchar tmpdin = 0; - uchar tmpdout = 0; - int j; + 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: chipsel %08X dout %08X din %08X bitlen %d\n", - (int)chipsel, *(uint *)dout, *(uint *)din, bitlen); + PRINTD("spi_xfer: slave %u:%u dout %08X din %08X bitlen %u\n", + slave->bus, slave->cs, *(uint *)txd, *(uint *)rxd, bitlen); - if(chipsel != NULL) { - (*chipsel)(1); /* select the target chip */ - } + 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) { - tmpdout = *dout++; + tmpdout = *txd++; if(j != 0) { - *din++ = tmpdin; + *rxd++ = tmpdin; } tmpdin = 0; } - SPI_SCL(0); + + if (!cpha) + SPI_SCL(!cpol); SPI_SDA(tmpdout & 0x80); SPI_DELAY; - SPI_SCL(1); + if (cpha) + SPI_SCL(!cpol); + else + SPI_SCL(cpol); + tmpdin <<= 1; + tmpdin |= SPI_READ; + tmpdout <<= 1; SPI_DELAY; - tmpdin <<= 1; - tmpdin |= SPI_READ; - tmpdout <<= 1; + if (cpha) + SPI_SCL(cpol); } /* * If the number of bits isn't a multiple of 8, shift the last @@ -120,14 +186,10 @@ int spi_xfer(spi_chipsel_type chipsel, int bitlen, uchar *dout, uchar *din) */ if((bitlen % 8) != 0) tmpdin <<= 8 - (bitlen % 8); - *din++ = tmpdin; - - SPI_SCL(0); /* SPI wants the clock left low for idle */ + *rxd++ = tmpdin; - if(chipsel != NULL) { - (*chipsel)(0); /* deselect the target chip */ - - } + if (flags & SPI_XFER_END) + spi_cs_deactivate(slave); return(0); } |