diff options
| author | Mark Brown <broonie@linaro.org> | 2014-03-29 23:48:07 +0000 |
|---|---|---|
| committer | Nitin Garg <nitin.garg@freescale.com> | 2015-09-17 09:20:38 -0500 |
| commit | a3bf74b325f2610a3e13aa43bdf38f5de09e7a92 (patch) | |
| tree | 794bf5c9c42014a6fac24eec76d45a8e51d12e05 /drivers/spi | |
| parent | 50c332917b171deb3c98903a9e6d15eb60624e54 (diff) | |
spi: Fix handling of cs_change in core implementation
The core implementation of cs_change didn't follow the documentation
which says that cs_change in the middle of the transfer means to briefly
deassert chip select, instead it followed buggy drivers which change the
polarity of chip select. Use a delay of 10us between deassert and
reassert simply from pulling numbers out of a hat.
Reported-by: Gerhard Sittig <gsi@denx.de>
Signed-off-by: Mark Brown <broonie@linaro.org>
(cherry picked from commit 0b73aa63c193006c3d503d4903dd4792a26e1d50)
(cherry picked from commit f5ec8bd357c3f3fddb46a9bf17293cc6f77d2563)
Diffstat (limited to 'drivers/spi')
| -rw-r--r-- | drivers/spi/spi.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c index c34179d3b93b..e4e8f92d8592 100644 --- a/drivers/spi/spi.c +++ b/drivers/spi/spi.c @@ -759,7 +759,6 @@ static int spi_transfer_one_message(struct spi_master *master, struct spi_message *msg) { struct spi_transfer *xfer; - bool cur_cs = true; bool keep_cs = false; int ret = 0; int ms = 1; @@ -805,8 +804,9 @@ static int spi_transfer_one_message(struct spi_master *master, &msg->transfers)) { keep_cs = true; } else { - cur_cs = !cur_cs; - spi_set_cs(msg->spi, cur_cs); + spi_set_cs(msg->spi, false); + udelay(10); + spi_set_cs(msg->spi, true); } } |