spi_mpc83xx: support loopback mode

This exposes the hardware loopback mode to drivers, primarily for testing.

Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com>
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 00:38:45 -07:00 committed by Linus Torvalds
parent 22b238bdb9
commit 2a485d7ad2
1 changed files with 6 additions and 2 deletions

View File

@ -39,6 +39,7 @@ struct mpc83xx_spi_reg {
};
/* SPI Controller mode register definitions */
#define SPMODE_LOOP (1 << 30)
#define SPMODE_CI_INACTIVEHIGH (1 << 29)
#define SPMODE_CP_BEGIN_EDGECLK (1 << 28)
#define SPMODE_DIV16 (1 << 27)
@ -155,7 +156,7 @@ static void mpc83xx_spi_chipselect(struct spi_device *spi, int value)
/* mask out bits we are going to set */
regval &= ~(SPMODE_CP_BEGIN_EDGECLK | SPMODE_CI_INACTIVEHIGH
| SPMODE_LEN(0xF) | SPMODE_DIV16
| SPMODE_PM(0xF) | SPMODE_REV);
| SPMODE_PM(0xF) | SPMODE_REV | SPMODE_LOOP);
if (spi->mode & SPI_CPHA)
regval |= SPMODE_CP_BEGIN_EDGECLK;
@ -163,6 +164,8 @@ static void mpc83xx_spi_chipselect(struct spi_device *spi, int value)
regval |= SPMODE_CI_INACTIVEHIGH;
if (!(spi->mode & SPI_LSB_FIRST))
regval |= SPMODE_REV;
if (spi->mode & SPI_LOOP)
regval |= SPMODE_LOOP;
regval |= SPMODE_LEN(len);
@ -273,7 +276,8 @@ 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 | SPI_LSB_FIRST)
#define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH \
| SPI_LSB_FIRST | SPI_LOOP)
static int mpc83xx_spi_setup(struct spi_device *spi)
{