[PATCH AUTOSEL 5.7 257/274] spi: spi-fsl-dspi: fix native data copy

Sasha Levin
2020-06-09T00:45:51Z

From: Angelo Dureghello <angelo.dureghello@timesys.com>

[ Upstream commit 263b81dc6c932c8bc550d5e7bfc178d2b3fc491e ]

ColdFire is a big-endian cpu with a big-endian dspi hw module,
so, it uses native access, but memcpy breaks the endianness.

So, if i understand properly, by native copy we would mean
be(cpu)->be(dspi) or le(cpu)->le(dspi) accesses, so my fix
shouldn't break anything, but i couldn't test it on LS family,
so every test is really appreciated.

Fixes: 53fadb4d90c7 ("spi: spi-fsl-dspi: Simplify bytes_per_word gymnastics")
Signed-off-by: Angelo Dureghello <angelo.dureghello@timesys.com>
Tested-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Link: https://lore.kernel.org/r/20200529195756.184677-1-angelo.dureghello@timesys.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/spi/spi-fsl-dspi.c | 24 ++++++++++++++++++++++--
1 file changed, 22 insertions(+), 2 deletions(-)

diff --git a/drivers/spi/spi-fsl-dspi.c b/drivers/spi/spi-fsl-dspi.c
index 50e41f66a2d7..2e9f9adc5900 100644
--- a/drivers/spi/spi-fsl-dspi.c
+++ b/drivers/spi/spi-fsl-dspi.c
@@ -246,13 +246,33 @@ struct fsl_dspi {

static void dspi_native_host_to_dev(struct fsl_dspi *dspi, u32 *txdata)
{
- memcpy(txdata, dspi->tx, dspi->oper_word_size);
+ switch (dspi->oper_word_size) {
+ case 1:
+ *txdata = *(u8 *)dspi->tx;
+ break;
+ case 2:
+ *txdata = *(u16 *)dspi->tx;
+ break;
+ case 4:
+ *txdata = *(u32 *)dspi->tx;
+ break;
+ }
dspi->tx += dspi->oper_word_size;
}

static void dspi_native_dev_to_host(struct fsl_dspi *dspi, u32 rxdata)
{
- memcpy(dspi->rx, &rxdata, dspi->oper_word_size);
+ switch (dspi->oper_word_size) {
+ case 1:
+ *(u8 *)dspi->rx = rxdata;
+ break;
+ case 2:
+ *(u16 *)dspi->rx = rxdata;
+ break;
+ case 4:
+ *(u32 *)dspi->rx = rxdata;
+ break;
+ }
dspi->rx += dspi->oper_word_size;
}

--
2.25.1