When SPI wake up from OFF mode, CS is in the wrong state: force it to
the inactive state.
During the system life, I monitored the CS behavior using a
oscilloscope. I also activated debug in omap2_mcspi, so I saw when
driver disable the clocks and restore context when device is not used.
Each time the CS was in the correct state.
It was only when system was put suspend to ram with off-mode activated
that on resume the CS was in wrong state( ie activated).
Signed-off-by: Gregory CLEMENT <gregory.clement@xxxxxxxxxxxxxxxxxx>
---
drivers/spi/omap2_mcspi.c | 10 ++++++++++
1 files changed, 10 insertions(+), 0 deletions(-)
diff --git a/drivers/spi/omap2_mcspi.c b/drivers/spi/omap2_mcspi.c
index 2a651e6..938f14c 100644
--- a/drivers/spi/omap2_mcspi.c
+++ b/drivers/spi/omap2_mcspi.c
@@ -1139,6 +1139,15 @@ static u8 __initdata spi4_txdma_id[] = {
};
#endif
+/* When SPI wake up, CS is in wrong state: force it to unactive state*/
+static void omap2_mcspi_resume(struct spi_device *spi)
+{
+ omap2_mcspi_enable_clocks( spi_master_get_devdata(spi->master));
+ /* We need to togle CS state for OMAP take this chang in account*/
+ omap2_mcspi_force_cs(spi, 1);
+ omap2_mcspi_force_cs(spi, 0);
+ omap2_mcspi_disable_clocks( spi_master_get_devdata(spi->master));
+}
static int __init omap2_mcspi_probe(struct platform_device *pdev)
{
struct spi_master *master;
@@ -1194,6 +1203,7 @@ static int __init omap2_mcspi_probe(struct
platform_device *pdev)
master->transfer = omap2_mcspi_transfer;
master->cleanup = omap2_mcspi_cleanup;
master->num_chipselect = num_chipselect;
+ master->resume = omap2_mcspi_resume;
dev_set_drvdata(&pdev->dev, master);
-- 1.7.0.4
--
To unsubscribe from this list: send the line "unsubscribe linux-omap" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
