[PATCH] spi: sprd: Fix the error data length in SPI read-only mode

From: Lanqing Liu
Date: Tue Jan 15 2019 - 08:46:50 EST


In SPI read-only mode, we will always return the writing length,
which is always the power of "bits_per_word", but the length unit
using by users is byte.

Thus this patch fixes the returning length by getting from
read_bufs() function to get the correct length.

Signed-off-by: Lanqing Liu <lanqing.liu@xxxxxxxxxxxxxx>
Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
drivers/spi/spi-sprd.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/spi/spi-sprd.c b/drivers/spi/spi-sprd.c
index 8daa24eec624..fa324ce194b2 100644
--- a/drivers/spi/spi-sprd.c
+++ b/drivers/spi/spi-sprd.c
@@ -380,7 +380,7 @@ static int sprd_spi_txrx_bufs(struct spi_device *sdev, struct spi_transfer *t)
{
struct sprd_spi *ss = spi_controller_get_devdata(sdev->controller);
u32 trans_len = ss->trans_len, len;
- int ret, write_size = 0;
+ int ret, write_size = 0, read_size = 0;

while (trans_len) {
len = trans_len > SPRD_SPI_FIFO_SIZE ? SPRD_SPI_FIFO_SIZE :
@@ -416,13 +416,15 @@ static int sprd_spi_txrx_bufs(struct spi_device *sdev, struct spi_transfer *t)
goto complete;

if (ss->trans_mode & SPRD_SPI_RX_MODE)
- ss->read_bufs(ss, len);
+ read_size += ss->read_bufs(ss, len);

trans_len -= len;
}

- ret = write_size;
-
+ if (ss->trans_mode & SPRD_SPI_TX_MODE)
+ ret = write_size;
+ else
+ ret = read_size;
complete:
sprd_spi_enter_idle(ss);

--
2.20.1