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Looks like this is a fallback. >>>> >>>> Should all of this be handled in the case statement for t->bus_freq_hz? >>>> >>> >>> HS mode timing parameters are programmed in registers different from the other >>> speed modes. These registers does not affect the timing in other speed modes. >>> HS mode registers being used or not is determined by the packet header. >>> >>> We may also want to program the regular timing registers, because it will be >>> used for the master code byte to transition to HS mode. >>> >>> So, I guess, even if we move this to the switch statement, we might end up >>> doing something similar outside it. >> >> >> The 'tlow', 'thigh' and 'tsu_thd' are configured under the case >> statement and so seems logical to also configure these for HS mode under >> this too. I see that there are different timing registers for HS mode, > > We are just reusing the variables since the fields are similar. If required, > we can define separate variables with _hs suffix. Do you suggest it that way? > >> but right now looks like we are programming both the normal ones and HS >> ones. Do both need to be programmed for HS mode? > > Yes. As mentioned in my previous comment, the normal timing registers will > be used for the 'master code' byte sent to transition to HS mode. We need > to program both for HS mode. OK, I see now. So we need to program the normal timings first and then we are re-using the variables to then program the HS timings. And because of that we cannot setup the HS timing values in the existing case statement? > So, I am not sure if moving this section to the switch block will add > any benefit. We might end up making it more complicated that it is now. Yes that's true. It was really this else part that caught my eye ... } else if (t->bus_freq_hz > I2C_MAX_FAST_MODE_PLUS_FREQ) { t->bus_freq_hz = I2C_MAX_FAST_MODE_PLUS_FREQ; } It feels like at least this part should be handled as part of the case statement. Jon -- nvpublic