diff options
Diffstat (limited to 'drivers/spi/spi-mxs.c')
| -rw-r--r-- | drivers/spi/spi-mxs.c | 36 |
1 files changed, 13 insertions, 23 deletions
diff --git a/drivers/spi/spi-mxs.c b/drivers/spi/spi-mxs.c index 68ea5078..a9a273e 100644 --- a/drivers/spi/spi-mxs.c +++ b/drivers/spi/spi-mxs.c @@ -140,18 +140,6 @@ static uint32_t mxs_spi_cs_to_reg(unsigned cs) return select; } -static void mxs_spi_set_cs(struct mxs_spi *spi, unsigned cs) -{ - const uint32_t mask = - BM_SSP_CTRL0_WAIT_FOR_CMD | BM_SSP_CTRL0_WAIT_FOR_IRQ; - uint32_t select; - struct mxs_ssp *ssp = &spi->ssp; - - writel(mask, ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_CLR); - select = mxs_spi_cs_to_reg(cs); - writel(select, ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET); -} - static int mxs_ssp_wait(struct mxs_spi *spi, int offset, int mask, bool set) { const unsigned long timeout = jiffies + msecs_to_jiffies(SSP_TIMEOUT); @@ -189,7 +177,7 @@ static irqreturn_t mxs_ssp_irq_handler(int irq, void *dev_id) return IRQ_HANDLED; } -static int mxs_spi_txrx_dma(struct mxs_spi *spi, int cs, +static int mxs_spi_txrx_dma(struct mxs_spi *spi, unsigned char *buf, int len, unsigned int flags) { @@ -217,10 +205,11 @@ static int mxs_spi_txrx_dma(struct mxs_spi *spi, int cs, INIT_COMPLETION(spi->c); + /* Chip select was already programmed into CTRL0 */ ctrl0 = readl(ssp->base + HW_SSP_CTRL0); ctrl0 &= ~(BM_SSP_CTRL0_XFER_COUNT | BM_SSP_CTRL0_IGNORE_CRC | BM_SSP_CTRL0_READ); - ctrl0 |= BM_SSP_CTRL0_DATA_XFER | mxs_spi_cs_to_reg(cs); + ctrl0 |= BM_SSP_CTRL0_DATA_XFER; if (!(flags & TXRX_WRITE)) ctrl0 |= BM_SSP_CTRL0_READ; @@ -324,7 +313,7 @@ err_mapped: return ret; } -static int mxs_spi_txrx_pio(struct mxs_spi *spi, int cs, +static int mxs_spi_txrx_pio(struct mxs_spi *spi, unsigned char *buf, int len, unsigned int flags) { @@ -333,8 +322,6 @@ static int mxs_spi_txrx_pio(struct mxs_spi *spi, int cs, writel(BM_SSP_CTRL0_IGNORE_CRC, ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_CLR); - mxs_spi_set_cs(spi, cs); - while (len--) { if (len == 0 && (flags & TXRX_DEASSERT_CS)) writel(BM_SSP_CTRL0_IGNORE_CRC, @@ -396,9 +383,12 @@ static int mxs_spi_transfer_one(struct spi_master *master, struct spi_transfer *t, *tmp_t; unsigned int flag; int status = 0; - int cs; - cs = m->spi->chip_select; + /* Program CS register bits here, it will be used for all transfers. */ + writel(BM_SSP_CTRL0_WAIT_FOR_CMD | BM_SSP_CTRL0_WAIT_FOR_IRQ, + ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_CLR); + writel(mxs_spi_cs_to_reg(m->spi->chip_select), + ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET); list_for_each_entry_safe(t, tmp_t, &m->transfers, transfer_list) { @@ -431,11 +421,11 @@ static int mxs_spi_transfer_one(struct spi_master *master, STMP_OFFSET_REG_CLR); if (t->tx_buf) - status = mxs_spi_txrx_pio(spi, cs, + status = mxs_spi_txrx_pio(spi, (void *)t->tx_buf, t->len, flag | TXRX_WRITE); if (t->rx_buf) - status = mxs_spi_txrx_pio(spi, cs, + status = mxs_spi_txrx_pio(spi, t->rx_buf, t->len, flag); } else { @@ -444,11 +434,11 @@ static int mxs_spi_transfer_one(struct spi_master *master, STMP_OFFSET_REG_SET); if (t->tx_buf) - status = mxs_spi_txrx_dma(spi, cs, + status = mxs_spi_txrx_dma(spi, (void *)t->tx_buf, t->len, flag | TXRX_WRITE); if (t->rx_buf) - status = mxs_spi_txrx_dma(spi, cs, + status = mxs_spi_txrx_dma(spi, t->rx_buf, t->len, flag); } |