Messages in this thread | | | From | Lakshmi Yadlapati <> | Date | Fri, 27 Oct 2023 03:25:14 +0000 | Subject | RE: [PATCH v4] hwmon: (pmbus/max31785) Add delay between bus accesses |
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On 10/26/23, 6:02 PM, "Guenter Roeck" <groeck7@gmail.com <mailto:groeck7@gmail.com> on behalf of linux@roeck-us.net <mailto:linux@roeck-us.net>> wrote:
On 10/26/23 15:17, Lakshmi Yadlapati wrote: > The MAX31785 has shown erratic behaviour across multiple system > designs, unexpectedly clock stretching and NAKing transactions. > > Experimentation shows that this seems to be triggered by a register access > directly back to back with a previous register write. Experimentation also > shows that inserting a small delay after register writes makes the issue go > away. > > Use a similar solution to what the max15301 driver does to solve the same > problem. Create a custom set of bus read and write functions that make sure > that the delay is added. > > Signed-off-by: Lakshmi Yadlapati <lakshmiy@us.ibm.com <mailto:lakshmiy@us.ibm.com>> > --- > V3 -> V4: Fixed warnings realted to this commit
>I also asked about the use of udelay() instead of usleep_range() or fsleep(). >I see you did not change the code. Fine, but please explain why the use of >udelay() instead of the alternative is desirable or needed here, and don't >just ignore review feedback.
Sorry, I missed the comment, I will make changes and send it again.
Thanks, Lakshmi
>Thanks, >Guenter
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