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-rw-r--r--drivers/spi/spi-mxs.c36
1 files changed, 13 insertions, 23 deletions
diff --git a/drivers/spi/spi-mxs.c b/drivers/spi/spi-mxs.c
index 68ea5078a9cf..a9a273e20fd2 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);
}