X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=drivers%2Fspi%2Fspi_mpc83xx.c;h=fe69e94043e1fad93779d1d167ef48a300e57a5e;hb=e24a4d1ee337e3a67a502f3f19cdec3ffc45ad05;hp=e9798bf7b8c6a0dff43795edc1ec1ee36ade6c42;hpb=7e23772f414cdbfb2a08aed237d6e926bb1cb728;p=linux-2.6 diff --git a/drivers/spi/spi_mpc83xx.c b/drivers/spi/spi_mpc83xx.c index e9798bf7b8..fe69e94043 100644 --- a/drivers/spi/spi_mpc83xx.c +++ b/drivers/spi/spi_mpc83xx.c @@ -39,6 +39,7 @@ struct mpc83xx_spi_reg { }; /* SPI Controller mode register definitions */ +#define SPMODE_LOOP (1 << 30) #define SPMODE_CI_INACTIVEHIGH (1 << 29) #define SPMODE_CP_BEGIN_EDGECLK (1 << 28) #define SPMODE_DIV16 (1 << 27) @@ -47,6 +48,7 @@ struct mpc83xx_spi_reg { #define SPMODE_ENABLE (1 << 24) #define SPMODE_LEN(x) ((x) << 20) #define SPMODE_PM(x) ((x) << 16) +#define SPMODE_OP (1 << 14) /* * Default for SPI Mode: @@ -84,7 +86,12 @@ struct mpc83xx_spi { unsigned nsecs; /* (clock cycle time)/2 */ - u32 sysclk; + u32 spibrg; /* SPIBRG input clock */ + u32 rx_shift; /* RX data reg shift when in qe mode */ + u32 tx_shift; /* TX data reg shift when in qe mode */ + + bool qe_mode; + void (*activate_cs) (u8 cs, u8 polarity); void (*deactivate_cs) (u8 cs, u8 polarity); }; @@ -103,7 +110,7 @@ static inline u32 mpc83xx_spi_read_reg(__be32 __iomem * reg) void mpc83xx_spi_rx_buf_##type(u32 data, struct mpc83xx_spi *mpc83xx_spi) \ { \ type * rx = mpc83xx_spi->rx; \ - *rx++ = (type)data; \ + *rx++ = (type)(data >> mpc83xx_spi->rx_shift); \ mpc83xx_spi->rx = rx; \ } @@ -114,7 +121,7 @@ u32 mpc83xx_spi_tx_buf_##type(struct mpc83xx_spi *mpc83xx_spi) \ const type * tx = mpc83xx_spi->tx; \ if (!tx) \ return 0; \ - data = *tx++; \ + data = *tx++ << mpc83xx_spi->tx_shift; \ mpc83xx_spi->tx = tx; \ return data; \ } @@ -147,23 +154,38 @@ static void mpc83xx_spi_chipselect(struct spi_device *spi, int value) len = len - 1; /* mask out bits we are going to set */ - regval &= ~0x38ff0000; + regval &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH + | SPMODE_LEN(0xF) | SPMODE_DIV16 + | SPMODE_PM(0xF) | SPMODE_REV | SPMODE_LOOP); if (spi->mode & SPI_CPHA) regval |= SPMODE_CP_BEGIN_EDGECLK; if (spi->mode & SPI_CPOL) regval |= SPMODE_CI_INACTIVEHIGH; + if (!(spi->mode & SPI_LSB_FIRST)) + regval |= SPMODE_REV; + if (spi->mode & SPI_LOOP) + regval |= SPMODE_LOOP; regval |= SPMODE_LEN(len); - if ((mpc83xx_spi->sysclk / spi->max_speed_hz) >= 64) { - u8 pm = mpc83xx_spi->sysclk / (spi->max_speed_hz * 64); + if ((mpc83xx_spi->spibrg / spi->max_speed_hz) >= 64) { + u8 pm = mpc83xx_spi->spibrg / (spi->max_speed_hz * 64); + if (pm > 0x0f) { + dev_err(&spi->dev, "Requested speed is too " + "low: %d Hz. Will use %d Hz instead.\n", + spi->max_speed_hz, + mpc83xx_spi->spibrg / 1024); + pm = 0x0f; + } regval |= SPMODE_PM(pm) | SPMODE_DIV16; } else { - u8 pm = mpc83xx_spi->sysclk / (spi->max_speed_hz * 4); + u8 pm = mpc83xx_spi->spibrg / (spi->max_speed_hz * 4); regval |= SPMODE_PM(pm); } + /* Turn off SPI unit prior changing mode */ + mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, 0); mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, regval); if (mpc83xx_spi->activate_cs) mpc83xx_spi->activate_cs(spi->chip_select, pol); @@ -197,18 +219,36 @@ int mpc83xx_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t) || ((bits_per_word > 16) && (bits_per_word != 32))) return -EINVAL; + mpc83xx_spi->rx_shift = 0; + mpc83xx_spi->tx_shift = 0; if (bits_per_word <= 8) { mpc83xx_spi->get_rx = mpc83xx_spi_rx_buf_u8; mpc83xx_spi->get_tx = mpc83xx_spi_tx_buf_u8; + if (mpc83xx_spi->qe_mode) { + mpc83xx_spi->rx_shift = 16; + mpc83xx_spi->tx_shift = 24; + } } else if (bits_per_word <= 16) { mpc83xx_spi->get_rx = mpc83xx_spi_rx_buf_u16; mpc83xx_spi->get_tx = mpc83xx_spi_tx_buf_u16; + if (mpc83xx_spi->qe_mode) { + mpc83xx_spi->rx_shift = 16; + mpc83xx_spi->tx_shift = 16; + } } else if (bits_per_word <= 32) { mpc83xx_spi->get_rx = mpc83xx_spi_rx_buf_u32; mpc83xx_spi->get_tx = mpc83xx_spi_tx_buf_u32; } else return -EINVAL; + if (mpc83xx_spi->qe_mode && spi->mode & SPI_LSB_FIRST) { + mpc83xx_spi->tx_shift = 0; + if (bits_per_word <= 8) + mpc83xx_spi->rx_shift = 8; + else + mpc83xx_spi->rx_shift = 0; + } + /* nsecs = (clock period)/2 */ if (!hz) hz = spi->max_speed_hz; @@ -223,21 +263,35 @@ int mpc83xx_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t) regval = mpc83xx_spi_read_reg(&mpc83xx_spi->base->mode); - /* Mask out bits_per_wordgth */ - regval &= 0xff0fffff; + /* mask out bits we are going to set */ + regval &= ~(SPMODE_LEN(0xF) | SPMODE_REV); regval |= SPMODE_LEN(bits_per_word); + if (!(spi->mode & SPI_LSB_FIRST)) + regval |= SPMODE_REV; + /* Turn off SPI unit prior changing mode */ + mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, 0); mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, regval); return 0; } +/* the spi->mode bits understood by this driver: */ +#define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH \ + | SPI_LSB_FIRST | SPI_LOOP) + static int mpc83xx_spi_setup(struct spi_device *spi) { struct spi_bitbang *bitbang; struct mpc83xx_spi *mpc83xx_spi; int retval; + if (spi->mode & ~MODEBITS) { + dev_dbg(&spi->dev, "setup: unsupported mode bits %x\n", + spi->mode & ~MODEBITS); + return -EINVAL; + } + if (!spi->max_speed_hz) return -EINVAL; @@ -371,18 +425,29 @@ static int __init mpc83xx_spi_probe(struct platform_device *dev) ret = -ENODEV; goto free_master; } - mpc83xx_spi = spi_master_get_devdata(master); mpc83xx_spi->bitbang.master = spi_master_get(master); mpc83xx_spi->bitbang.chipselect = mpc83xx_spi_chipselect; mpc83xx_spi->bitbang.setup_transfer = mpc83xx_spi_setup_transfer; mpc83xx_spi->bitbang.txrx_bufs = mpc83xx_spi_bufs; - mpc83xx_spi->sysclk = pdata->sysclk; mpc83xx_spi->activate_cs = pdata->activate_cs; mpc83xx_spi->deactivate_cs = pdata->deactivate_cs; + mpc83xx_spi->qe_mode = pdata->qe_mode; mpc83xx_spi->get_rx = mpc83xx_spi_rx_buf_u8; mpc83xx_spi->get_tx = mpc83xx_spi_tx_buf_u8; + if (mpc83xx_spi->qe_mode) + mpc83xx_spi->spibrg = pdata->sysclk / 2; + else + mpc83xx_spi->spibrg = pdata->sysclk; + + mpc83xx_spi->rx_shift = 0; + mpc83xx_spi->tx_shift = 0; + if (mpc83xx_spi->qe_mode) { + mpc83xx_spi->rx_shift = 16; + mpc83xx_spi->tx_shift = 24; + } + mpc83xx_spi->bitbang.master->setup = mpc83xx_spi_setup; init_completion(&mpc83xx_spi->done); @@ -417,6 +482,9 @@ static int __init mpc83xx_spi_probe(struct platform_device *dev) /* Enable SPI interface */ regval = pdata->initial_spmode | SPMODE_INIT_VAL | SPMODE_ENABLE; + if (pdata->qe_mode) + regval |= SPMODE_OP; + mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, regval); ret = spi_bitbang_start(&mpc83xx_spi->bitbang);