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

[Caesar Wang]

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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