Re: [PATCH] i2c: rk3x: Increase wait timeout to 1 second

From: Caesar Wang
Date: Thu Apr 30 2015 - 23:45:34 EST




å 2015å05æ01æ 05:44, Doug Anderson åé:
While it's not sensible for an i2c command to _actually_ need more
than 200ms to complete, let's increase the timeout anyway. Why? It
turns out that if you've got a large number of printks going out to a
serial console, interrupts on a CPU can be disabled for hundreds of
milliseconds. That's not a great situation to be in to start with
(maybe we should put a cap in vprintk_emit()) but it's pretty annoying
to start seeing unexplained i2c timeouts.

A normal system shouldn't see i2c timeouts anyway, so increasing the
timeout should help people debugging without hurting other people
excessively.

Signed-off-by: Doug Anderson <dianders@xxxxxxxxxxxx>
---
drivers/i2c/busses/i2c-rk3x.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-rk3x.c b/drivers/i2c/busses/i2c-rk3x.c
index 019d542..72e97e30 100644
--- a/drivers/i2c/busses/i2c-rk3x.c
+++ b/drivers/i2c/busses/i2c-rk3x.c
@@ -72,7 +72,7 @@ enum {
#define REG_INT_ALL 0x7f
/* Constants */
-#define WAIT_TIMEOUT 200 /* ms */
+#define WAIT_TIMEOUT 1000 /* ms */
Yeah,verified on veyron device.

Tested-by: Caesar Wang <wxt@xxxxxxxxxxxxxx>

Thanks.
Caesar

#define DEFAULT_SCL_RATE (100 * 1000) /* Hz */
enum rk3x_i2c_state {


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