diff options
authorDoug Anderson <dianders@chromium.org>2014-08-28 16:43:48 -0700
committerMark Brown <broonie@kernel.org>2014-08-29 12:07:38 +0100
commit5d1d150d7d775db1dccb4dc4676075d456dea392 (patch)
parent0ac7a4904ae1a73ae4c2c18ff6a5dd2b7e03254c (diff)
spi/rockchip: Avoid accidentally turning off the clock
If our client is requesting a clock that is above the maximum clock then the following division will result in 0: rs->max_freq / rs->speed We'll then program 0 into the SPI_BAUDR register. The Rockchip TRM says: "If the value is 0, the serial output clock (sclk_out) is disabled." It's much better to end up with the fastest possible clock rather than a clock that is off, so enforce a minimum value. Signed-off-by: Doug Anderson <dianders@chromium.org> Signed-off-by: Mark Brown <broonie@kernel.org>
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c
index 6321326eb751..cd0e08b0c9f6 100644
--- a/drivers/spi/spi-rockchip.c
+++ b/drivers/spi/spi-rockchip.c
@@ -499,7 +499,7 @@ static void rockchip_spi_config(struct rockchip_spi *rs)
/* div doesn't support odd number */
- div = rs->max_freq / rs->speed;
+ div = max_t(u32, rs->max_freq / rs->speed, 1);
div = (div + 1) & 0xfffe;
spi_enable_chip(rs, 0);