On Fri, Dec 16, 2022 at 12:02:27PM +0100, Oleksij Rempel wrote:
On Fri, Dec 16, 2022 at 11:41:08AM +0100, Primoz Fiser wrote:
Hi Marco,
On 16. 12. 22 10:45, Marco Felsch wrote:
Hi Primoz,
On 22-12-16, Primoz Fiser wrote:
By default, retries value is set to 0 (no retries). Set retries to more
sensible value of 3 to allow i2c core to re-attempt transfer in case of
i2c arbitration loss (i2c-imx returns -EAGAIN errno is such case).
apart the fact that the number of retries vary a lot and so the client
driver behaviour can vary a lot which is not good IMHO, why do you think
that 3 is a sufficient number?
IMHO it is better than leaving it at 0 (no retries)?
Setting it to sensible value like 3 will at least attempt to make transfer
in case arbitration-loss occurs.
If an arbitration loss happen, why do you think that retrying it 3 times
changes that?
I our case, setting retries to non-zero value solves issues with PMIC
shutdown on phyboard-mira which in some rare cases fails with "Failed to
shutdown (err = -11)" (-EAGAIN).
To me it makes common sense retries is set to non-zero value especially for
such rare conditions/situations.
https://lore.kernel.org/all/Ys1bw9zuIwWS+bqw@shikoro/
Also in the same thread there is the question about better setting it in
the i2c core if 3 instead of 0 is a good idea for the imx driver.
Best regards
Uwe