[PATCH 3/9] spi_mpc83xx: Add small delay after assertingchip-select line

From: Anton Vorontsov
Date: Thu Apr 30 2009 - 19:49:33 EST


This is needed for some underlaying GPIO controllers that may be
a bit slow, or if chip-select signal need some time to stabilize.

For what it's worth, we already have the similar delay for
chip-select de-assertion case.

Signed-off-by: Anton Vorontsov <avorontsov@xxxxxxxxxxxxx>
---
drivers/spi/spi_mpc83xx.c | 4 +++-
1 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/drivers/spi/spi_mpc83xx.c b/drivers/spi/spi_mpc83xx.c
index 08b49d2..d378d5e 100644
--- a/drivers/spi/spi_mpc83xx.c
+++ b/drivers/spi/spi_mpc83xx.c
@@ -383,8 +383,10 @@ static void mpc83xx_spi_work(struct work_struct *work)
break;
}

- if (cs_change)
+ if (cs_change) {
mpc83xx_spi_chipselect(spi, BITBANG_CS_ACTIVE);
+ ndelay(nsecs);
+ }
cs_change = t->cs_change;
if (t->len)
status = mpc83xx_spi_bufs(spi, t);
--
1.6.2.2

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