From: Christophe Leroy christophe.leroy@csgroup.eu
[ Upstream commit c20c57d9868d7f9fd1b2904c7801b07e128f6322 ]
CPM has the same problem as QE so for CPM also use the fix added by commit 0398fb70940e ("spi/spi_mpc8xxx: Fix QE mode Litte Endian"):
CPM mode uses Little Endian so words > 8 bits are byte swapped. Workaround this by always enforcing wordsize 8 for 16 and 32 bits words. Unfortunately this will not work for LSB transfers where wordsize is > 8 bits so disable these for now.
Also limit the workaround to 16 and 32 bits words because it can only work for multiples of 8-bits.
Signed-off-by: Christophe Leroy christophe.leroy@csgroup.eu Cc: Joakim Tjernlund Joakim.Tjernlund@infinera.com Fixes: 0398fb70940e ("spi/spi_mpc8xxx: Fix QE mode Litte Endian") Link: https://lore.kernel.org/r/1b7d3e84b1128f42c1887dd2fb9cdf390f541bc1.168037180... Signed-off-by: Mark Brown broonie@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/spi/spi-fsl-spi.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-)
diff --git a/drivers/spi/spi-fsl-spi.c b/drivers/spi/spi-fsl-spi.c index 93152144fd2ec..5602f052b2b50 100644 --- a/drivers/spi/spi-fsl-spi.c +++ b/drivers/spi/spi-fsl-spi.c @@ -181,8 +181,8 @@ static int mspi_apply_qe_mode_quirks(struct spi_mpc8xxx_cs *cs, struct spi_device *spi, int bits_per_word) { - /* QE uses Little Endian for words > 8 - * so transform all words > 8 into 8 bits + /* CPM/QE uses Little Endian for words > 8 + * so transform 16 and 32 bits words into 8 bits * Unfortnatly that doesn't work for LSB so * reject these for now */ /* Note: 32 bits word, LSB works iff @@ -190,9 +190,11 @@ static int mspi_apply_qe_mode_quirks(struct spi_mpc8xxx_cs *cs, if (spi->mode & SPI_LSB_FIRST && bits_per_word > 8) return -EINVAL; - if (bits_per_word > 8) + if (bits_per_word <= 8) + return bits_per_word; + if (bits_per_word == 16 || bits_per_word == 32) return 8; /* pretend its 8 bits */ - return bits_per_word; + return -EINVAL; }
static int fsl_spi_setup_transfer(struct spi_device *spi, @@ -222,7 +224,7 @@ static int fsl_spi_setup_transfer(struct spi_device *spi, bits_per_word = mspi_apply_cpu_mode_quirks(cs, spi, mpc8xxx_spi, bits_per_word); - else if (mpc8xxx_spi->flags & SPI_QE) + else bits_per_word = mspi_apply_qe_mode_quirks(cs, spi, bits_per_word);