spi_mpc83xx: support for lsb-first transfers

This controller supports LSB-first transfers; let drivers use them.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Anton Vorontsov 2007-07-31 00:38:41 -07:00 committed by Linus Torvalds
parent 20ba09b979
commit 32421daaf8

View file

@ -153,13 +153,16 @@ static void mpc83xx_spi_chipselect(struct spi_device *spi, int value)
len = len - 1;
/* mask out bits we are going to set */
regval &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH |
SPMODE_LEN(0xF) | SPMODE_DIV16 | SPMODE_PM(0xF));
regval &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH
| SPMODE_LEN(0xF) | SPMODE_DIV16
| SPMODE_PM(0xF) | SPMODE_REV);
if (spi->mode & SPI_CPHA)
regval |= SPMODE_CP_BEGIN_EDGECLK;
if (spi->mode & SPI_CPOL)
regval |= SPMODE_CI_INACTIVEHIGH;
if (!(spi->mode & SPI_LSB_FIRST))
regval |= SPMODE_REV;
regval |= SPMODE_LEN(len);
@ -248,9 +251,11 @@ int mpc83xx_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
regval = mpc83xx_spi_read_reg(&mpc83xx_spi->base->mode);
/* Mask out bits_per_wordgth */
regval &= ~SPMODE_LEN(0xF);
/* mask out bits we are going to set */
regval &= ~(SPMODE_LEN(0xF) | SPMODE_REV);
regval |= SPMODE_LEN(bits_per_word);
if (!(spi->mode & SPI_LSB_FIRST))
regval |= SPMODE_REV;
/* Turn off SPI unit prior changing mode */
mpc83xx_spi_write_reg(&mpc83xx_spi->base->mode, 0);
@ -260,7 +265,7 @@ int mpc83xx_spi_setup_transfer(struct spi_device *spi, struct spi_transfer *t)
}
/* the spi->mode bits understood by this driver: */
#define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH)
#define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LSB_FIRST)
static int mpc83xx_spi_setup(struct spi_device *spi)
{