[PATCH v1 1/4] spi: npcm-pspi: fix 16 bit send and receive support

From: Tomer Maimon
Date: Wed Jan 15 2020 - 12:08:00 EST


Fixing NPCM BMC Peripheral SPI controller 16 bit
send and receive support by writing and reading
the SPI data in the right order.

Signed-off-by: Tomer Maimon <tmaimon77@xxxxxxxxx>
---
drivers/spi/spi-npcm-pspi.c | 17 +++++++++--------
1 file changed, 9 insertions(+), 8 deletions(-)

diff --git a/drivers/spi/spi-npcm-pspi.c b/drivers/spi/spi-npcm-pspi.c
index fe624731c74c..c74611abe2a9 100644
--- a/drivers/spi/spi-npcm-pspi.c
+++ b/drivers/spi/spi-npcm-pspi.c
@@ -195,6 +195,7 @@ static void npcm_pspi_setup_transfer(struct spi_device *spi,
static void npcm_pspi_send(struct npcm_pspi *priv)
{
int wsize;
+ u16 val;

wsize = min(bytes_per_word(priv->bits_per_word), priv->tx_bytes);
priv->tx_bytes -= wsize;
@@ -204,17 +205,18 @@ static void npcm_pspi_send(struct npcm_pspi *priv)

switch (wsize) {
case 1:
- iowrite8(*priv->tx_buf, NPCM_PSPI_DATA + priv->base);
+ val = *priv->tx_buf++;
+ iowrite8(val, NPCM_PSPI_DATA + priv->base);
break;
case 2:
- iowrite16(*priv->tx_buf, NPCM_PSPI_DATA + priv->base);
+ val = *priv->tx_buf++;
+ val = *priv->tx_buf++ | (val << 8);
+ iowrite16(val, NPCM_PSPI_DATA + priv->base);
break;
default:
WARN_ON_ONCE(1);
return;
}
-
- priv->tx_buf += wsize;
}

static void npcm_pspi_recv(struct npcm_pspi *priv)
@@ -230,18 +232,17 @@ static void npcm_pspi_recv(struct npcm_pspi *priv)

switch (rsize) {
case 1:
- val = ioread8(priv->base + NPCM_PSPI_DATA);
+ *priv->rx_buf++ = ioread8(priv->base + NPCM_PSPI_DATA);
break;
case 2:
val = ioread16(priv->base + NPCM_PSPI_DATA);
+ *priv->rx_buf++ = (val >> 8);
+ *priv->rx_buf++ = val & 0xff;
break;
default:
WARN_ON_ONCE(1);
return;
}
-
- *priv->rx_buf = val;
- priv->rx_buf += rsize;
}

static int npcm_pspi_transfer_one(struct spi_master *master,
--
2.22.0