> -----Original Message----- > From: Marek Vasut <marex@xxxxxxx> > Sent: Wednesday, July 21, 2021 3:14 AM > To: Raviteja Narayanam <rna@xxxxxxxxxx>; Michal Simek > <michals@xxxxxxxxxx>; linux-i2c@xxxxxxxxxxxxxxx > Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; git > <git@xxxxxxxxxx>; joe@xxxxxxxxxxx > Subject: Re: [PATCH v2 00/10] i2c: xiic: Add features, bug fixes. > > On 7/20/21 4:19 PM, Raviteja Narayanam wrote: > > Hi, > > [...] > > >>> I have tested this again on our boards with eeprom and other > >>> sensors, this > >> is working fine for us. > >> > >> Can you share details of how those tests were performed ? > > > > Stress test - 1: > > Heavy ethernet traffic running in the background. > > I2c commands script (like below) running. We can see visible stutter in the > output as expected, but nothing failed. > > > > i=0 > > while [ 1 ] > > do > > i2ctransfer -y -f 2 w1@0X54 0X00 r31@0X54 > > i2ctransfer -y -f 2 w1@0X54 0X00 r32@0X54 > > i2ctransfer -y -f 2 w1@0X54 0X00 r255@0X54 > > i2ctransfer -y -f 2 w1@0X54 0X00 r273@0X54 > > i2ctransfer -y -f 2 w1@0X54 0X00 r1@0X54 > > Could it be that you never see the problem because you always talk to one > single device ? There are transfers to other devices as well. Our board has multiple power monitors, eeprom and other misc devices that are accessed through the same driver and are working fine. > > Do you also test writes which are not 1 byte long ? > Yes, like for eeprom 1 page (16 bytes) is written. > > i=$(expr $i + 1) > > echo "$i" > > done > > > > Stress test - 2: > > Two i2c scripts running in parallel with commands as shown above with > different bus numbers (as a result of mux), but going into same XIIC adapter. > > This is also working fine. > > Could it be the i2c-dev serializes each of those transfers , so no race can be > triggered ? > Yes, that is true because all our tests are going through the i2c-core only and there is a lock at adapter level in the core. It has to be reproducible through the i2c standard interface, which is not happening at our setup. I can take your patches that are targeted for this issue, rebase, test and send them. Regards, Raviteja N
