[U-Boot] [PATCH v2 15/18] spi: mpc8xxx: Re-order transfer setup
Mario Six
mario.six at gdsys.cc
Thu Apr 19 12:36:30 UTC 2018
Minize the time the adapter is disabled (via SPI_MODE_EN
clearing/setting) to just the character length setting, and only set up
the temporary data writing variable right before we need it, so there is
a more clear distinction between setting up the SPI adapter, and setting
up the data to be written.
Signed-off-by: Mario Six <mario.six at gdsys.cc>
---
Changes v1 -> v2:
None
---
drivers/spi/mpc8xxx_spi.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/drivers/spi/mpc8xxx_spi.c b/drivers/spi/mpc8xxx_spi.c
index d22206f4b7..fe493f6d40 100644
--- a/drivers/spi/mpc8xxx_spi.c
+++ b/drivers/spi/mpc8xxx_spi.c
@@ -117,9 +117,6 @@ int spi_xfer(struct spi_slave *slave, uint bitlen, const void *dout, void *din,
u32 tmpdout = 0;
uchar xfer_bitlen = (bitlen >= 32 ? 32 : bitlen);
- /* Shift data so it's msb-justified */
- tmpdout = *(u32 *)dout >> (32 - xfer_bitlen);
-
clrbits_be32(&spi->mode, SPI_MODE_EN);
/* Set up length for this transfer */
@@ -131,14 +128,17 @@ int spi_xfer(struct spi_slave *slave, uint bitlen, const void *dout, void *din,
else /* more than 16 bits -> full 32 bit transfer */
set_char_len(spi, 0);
+ setbits_be32(&spi->mode, SPI_MODE_EN);
+
+ /* Shift data so it's msb-justified */
+ tmpdout = *(u32 *)dout >> (32 - xfer_bitlen);
+
if (bitlen > 16) {
/* Set up the next iteration if sending > 32 bits */
bitlen -= 32;
dout += 4;
}
- setbits_be32(&spi->mode, SPI_MODE_EN);
-
/* Write the data out */
out_be32(&spi->tx, tmpdout);
--
2.16.1
More information about the U-Boot
mailing list