On Mon, Sep 30, 2019 at 5:01 PM Guenter Roeck <linux@xxxxxxxxxxxx> wrote: > > Again, I fail to understand why waiting for a multiple of 20 seconds > under any circumstances would make any sense. Maybe the idea was > to divide us by 1000 before entering the second loop ? Yes, that's very clearly a mistake of mine. > > Looking into the code, there is no need to use udelay() in the first > place. It should be possible to replace the longer waits with > usleep_range(). Something like > > if (us < some_low_value) // eg. 0x80 > delay(us) Did you mean udelay here? > else > usleep_range(us, us * 2); > > should do, and at the same time prevent the system from turning > into a space heater. The issue would persist with the above if udelay remains in a loop that gets fully unrolled. That's while I "peel" the loop into two loops over different ranges with different bodies. I think I should iterate in the first loop until the number of `us` is greater than 1000 (us per ms)(which is less of a magical constant and doesn't expose internal implementation details of udelay), then start the second loop (dividing us by 1000). What do you think, Guenter? -- Thanks, ~Nick Desaulniers
