From e61f487fd596ce570e87ccfdc0a7fc9fa87aced9 Mon Sep 17 00:00:00 2001 From: "Chew, Chiau Ee" Date: Fri, 13 Jun 2014 23:57:25 +0800 Subject: [PATCH] spi/pxa2xx: fix incorrect SW mode chipselect setting for BayTrail LPSS SPI It was observed that after module removal followed by insertion, the SW mode chipselect is not properly set. Thus causing transfer failure due to incorrect CS toggling. Signed-off-by: Chew, Chiau Ee Acked-by: Mika Westerberg Signed-off-by: Mark Brown --- drivers/spi/spi-pxa2xx.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c index a98df7eeb42d..fe792106bdc5 100644 --- a/drivers/spi/spi-pxa2xx.c +++ b/drivers/spi/spi-pxa2xx.c @@ -118,6 +118,7 @@ static void lpss_ssp_setup(struct driver_data *drv_data) */ orig = readl(drv_data->ioaddr + offset + SPI_CS_CONTROL); + /* Test SPI_CS_CONTROL_SW_MODE bit enabling */ value = orig | SPI_CS_CONTROL_SW_MODE; writel(value, drv_data->ioaddr + offset + SPI_CS_CONTROL); value = readl(drv_data->ioaddr + offset + SPI_CS_CONTROL); @@ -126,10 +127,13 @@ static void lpss_ssp_setup(struct driver_data *drv_data) goto detection_done; } - value &= ~SPI_CS_CONTROL_SW_MODE; + orig = readl(drv_data->ioaddr + offset + SPI_CS_CONTROL); + + /* Test SPI_CS_CONTROL_SW_MODE bit disabling */ + value = orig & ~SPI_CS_CONTROL_SW_MODE; writel(value, drv_data->ioaddr + offset + SPI_CS_CONTROL); value = readl(drv_data->ioaddr + offset + SPI_CS_CONTROL); - if (value != orig) { + if (value != (orig & ~SPI_CS_CONTROL_SW_MODE)) { offset = 0x800; goto detection_done; } -- GitLab