On 31 May 2016 09:56:51 BST, Crestez Dan Leonard <leonard.crestez@xxxxxxxxx> wrote: >On 05/31/2016 12:42 AM, Jonathan Cameron wrote: >> On 30 May 2016 14:44:41 BST, Crestez Dan Leonard ><leonard.crestez@xxxxxxxxx> wrote: >>> On 05/29/2016 06:47 PM, Jonathan Cameron wrote: >>>> On 18/05/16 16:00, Crestez Dan Leonard wrote: >>>>> Right now it is possible to only enable some of the x/y/z >channels, >>> for >>>>> example you can enable accel_z without x or y but if you actually >do >>>>> that what you get is actually only the x channel. >>>>> >>>>> Fix this by reformatting the hardware sample to only include the >>>>> requested channels. >>>> As it stands here there is no benefit in doing this over using the >>> core >>>> demux. In fact it's considerably less efficient (fair enough that >you >>>> are keeping it simple in the first instance). >>>> The patch description should make that clear. >>> >>> Why is it less efficient? All it really does is a bunch of memcpy. >> >> Not doing agglomeration of neighbouring copies (iirc) not git either >set of code to >> hand! > >You're right about that. But the total data rate is still very low. > >>>> I'd definitely like to see simple extension of that option to >handle >>>> a callback to get the nearest scanmask that is possible (as an >>> alternative >>>> to the static scan_masks_available list.) >>>> >>>> This only gets interesting if we are dealing with the unaligned >case >>> and for >>>> these parts that only kicks in I think if the slave devices have >say >>> 3 bytes in >>>> their data type. >>> >>> But I want to deal with the unaligned case because it's better than >>> introducing odd validations on slave channels. If I added an >extension >>> to get the nearest scanmask I would have to remove it in PATCH 7. >> Hmm I must have misread that. Though you were only supporting 16 bit >channels >> for aux sensors. > >That was in a previous version, I dropped that limitation now. > >> Then for now can we give this a slightly less generic name. I am not >happy >> enough that we want this in the core 'yet'. >> Easy to rename later if it makes sense. > >Ok, I will rename these functions to start with inv_mpu_* instead of >iio_*. > >In theory it would be interesting to refactor the iio demuxing code to >support this but then this patch serios would grow even more >complicated. Agreed. Let's leave that for a separate effort! I was vaguely wondering about letting the core demux input be unaligned but enforce the output keeping current alignment. Fiddly even then however. J -- Sent from my Android device with K-9 Mail. Please excuse my brevity. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
