From de5bf02cb1f61de0c65a539cd0083ac8ab07ec50 Mon Sep 17 00:00:00 2001
From: Fabio Estevam <fabio.estevam@freescale.com>
Date: Thu, 15 Nov 2012 11:23:23 +0000
Subject: [PATCH] spi: mxc_spi: Fix handling of chip select
In decode_cs() function the polarity of the chip select must be taken into
account.
Also, for the case of low active chip select, the CS was activated too early.
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
---
drivers/spi/mxc_spi.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/drivers/spi/mxc_spi.c b/drivers/spi/mxc_spi.c
index 13bebe8..b6bad98 100644
--- a/drivers/spi/mxc_spi.c
+++ b/drivers/spi/mxc_spi.c
@@ -387,7 +387,7 @@ static int decode_cs(struct mxc_spi_slave *mxcs, unsigned int cs)
if (cs > 3) {
mxcs->gpio = cs >> 8;
cs &= 3;
- ret = gpio_direction_output(mxcs->gpio, 0);
+ ret = gpio_direction_output(mxcs->gpio, !(mxcs->ss_pol));
if (ret) {
printf("mxc_spi: cannot setup gpio %d\n", mxcs->gpio);
return -EINVAL;
@@ -414,6 +414,8 @@ struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
return NULL;
}
+ mxcs->ss_pol = (mode & SPI_CS_HIGH) ? 1 : 0;
+
ret = decode_cs(mxcs, cs);
if (ret < 0) {
free(mxcs);
@@ -425,7 +427,6 @@ struct spi_slave *spi_setup_slave(unsigned int bus, unsigned int cs,
mxcs->slave.bus = bus;
mxcs->slave.cs = cs;
mxcs->base = spi_bases[bus];
- mxcs->ss_pol = (mode & SPI_CS_HIGH) ? 1 : 0;
ret = spi_cfg_mxc(mxcs, cs, max_hz, mode);
if (ret) {