Hi Andrew,
Andrew Lunn <and...@lunn.ch> writes:
> The mv88e6xxx driver times out operations on the switch based on
> looping until an elapsed wall clock time is reached. However, if
> usleep_range() sleeps much longer than expected, it could timeout with
> an error without actually checking to see if the devices has completed
> the operation. So replace the elapsed time with a fixed upper bound on
> the number of loops.
>
> Testing on various switches has shown that switches takes either 0 or
> 1 iteration, so a maximum of 16 iterations is a safe limit.
>
> Signed-off-by: Andrew Lunn <and...@lunn.ch>
> ---
> drivers/net/dsa/mv88e6xxx/chip.c | 15 ++++++---------
> 1 file changed, 6 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/net/dsa/mv88e6xxx/chip.c
> b/drivers/net/dsa/mv88e6xxx/chip.c
> index a230fcba5b64..ac8e9af4879f 100644
> --- a/drivers/net/dsa/mv88e6xxx/chip.c
> +++ b/drivers/net/dsa/mv88e6xxx/chip.c
> @@ -309,9 +309,9 @@ static int mv88e6xxx_serdes_write(struct mv88e6xxx_chip
> *chip, int reg, u16 val)
> static int mv88e6xxx_wait(struct mv88e6xxx_chip *chip, int addr, int reg,
> u16 mask)
> {
> - unsigned long timeout = jiffies + HZ / 10;
> + int i;
>
> - while (time_before(jiffies, timeout)) {
> + for (i = 0; i < 16; i++) {
> u16 val;
> int err;
>
Since we remove the elapsed time here, can we use mv88e6xxx_wait in
mv88e6xxx_update? It'd be good to have a consistent wait routine
everywhere.
Thanks,
Vivien
