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>

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>
Ira W. Snyder · Kim Phillips
1 parent 037e9d33db
Showing 1 changed file with 4 additions and 0 deletions Side-by-side Diff
drivers/spi/mpc8xxx_spi.c
@@ -124,6 +124,8 @@
 		 * len > 16               0
 		 */
  
+		spi->mode &= ~SPI_MODE_EN;
+
 		if (bitlen <= 16) {
 			if (bitlen <= 4)
 				spi->mode = (spi->mode & 0xff0fffff) |
@@ -137,6 +139,8 @@
 			bitlen -= 32;
 			dout += 4;
 		}
+
+		spi->mode |= SPI_MODE_EN;
  
 		spi->tx = tmpdout;	/* Write the data out */
 		debug("*** spi_xfer: ... %08x written\n", tmpdout);
...	...	@@ -124,6 +124,8 @@
124	124	* len > 16 0
125	125	*/
126	126
	127	+ spi->mode &= ~SPI_MODE_EN;
	128	+
127	129	if (bitlen <= 16) {
128	130	if (bitlen <= 4)
129	131	spi->mode = (spi->mode & 0xff0fffff) \|
...	...	@@ -137,6 +139,8 @@
137	139	bitlen -= 32;
138	140	dout += 4;
139	141	}
	142	+
	143	+ spi->mode \|= SPI_MODE_EN;
140	144
141	145	spi->tx = tmpdout; /* Write the data out */
142	146	debug("*** spi_xfer: ... %08x written\n", tmpdout);