mpc8xxx_spi: fix SPI support on MPC8308RDB

The MPC8308RDB Reference Manual states that no bits in the SPMODE
register are allowed to change while the enable (EN) bit is set.

This driver changes the character length bits (LEN) while the enable
(EN) bit is set. Clearing the EN bit while changing the LEN bits makes
the driver work correctly on MPC8308RDB.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
This commit is contained in:
Ira W. Snyder 2012-09-12 14:17:31 -07:00 committed by Kim Phillips
parent 037e9d33db
commit f138ca1373

View file

@ -124,6 +124,8 @@ int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
* len > 16 0 * len > 16 0
*/ */
spi->mode &= ~SPI_MODE_EN;
if (bitlen <= 16) { if (bitlen <= 16) {
if (bitlen <= 4) if (bitlen <= 4)
spi->mode = (spi->mode & 0xff0fffff) | spi->mode = (spi->mode & 0xff0fffff) |
@ -138,6 +140,8 @@ int spi_xfer(struct spi_slave *slave, unsigned int bitlen, const void *dout,
dout += 4; dout += 4;
} }
spi->mode |= SPI_MODE_EN;
spi->tx = tmpdout; /* Write the data out */ spi->tx = tmpdout; /* Write the data out */
debug("*** spi_xfer: ... %08x written\n", tmpdout); debug("*** spi_xfer: ... %08x written\n", tmpdout);