On Mon, 2015-05-04 at 11:21 +0300, Octavian Purdila wrote: > On Mon, May 4, 2015 at 4:11 AM, Sathyanarayanan Kuppuswamy > <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx> wrote: > > Hi Octavian, > > > > On 04/27/2015 07:23 PM, Octavian Purdila wrote: > >> > >> On Tue, Apr 28, 2015 at 12:57 AM, sathyanarayanan kuppuswamy > >> <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx> wrote: > >>> > >>> Hi > >>> > >>> On 04/27/2015 08:54 AM, Octavian Purdila wrote: > >>>> > >>>> On Mon, Apr 27, 2015 at 6:42 PM, Kuppuswamy Sathyanarayanan > >>>> <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx> wrote: > >>>>> > >>>>> Since Acpi framework already exports this info to user space, Why not > >>>>> do > >>>>> this derivation in user space code ? Why do we need new ABI, if the > >>>>> same > >>>>> can be derived from existing one. > >>>>> > >>>> The ABI was added in the previous patch so that we can present the > >>>> sensor orientation information to userspace even in the case of device > >>>> tree. > >>> > >>> If the main reason for implementing a new ABI is to support DT platforms, > >>> Why not implement a version of _PLD for device tree ? Don't you think it > >>> would be much better than adding a new ABI to export redundant > >>> information ? > >>> > >> IMO the mounting matrix is more consistent with the IIO ABIs. Although > >> I have no issue with repicating _PLD for device tree if people agree > >> that it is better. > > > > Since your main issue is, device tree lacking ABI to specify location > > information, you should consider fixing it there. Let's wait for others > > comment on this. > > > > If you think mounting matrix provides more information than what is > > supported > > by _PLD, then we should consider implementing another ABI. AFAIK, that is > > not > > the case here. > > > > Adding adding a new ABI to represent the information that can be derived > > from existing ABI does not seem to be useful. > > AFAICS the ACPI _PLD information is not (yet) exported to userspace. This patch: > > http://marc.info/?t=140795040700003&r=1&w=2 > > does not seem to be merged upstream. So there is no existing ABI to > derive from :) I don't think there is any major objection to this patch. The author should just try and see if he can replace to device_* calls. Thanks, Srinivas > > >> > >> > >>> Also the location information of the device is not just specific to iio > >>> drivers. You should consider that we would have similar requirements for > >>> devices implemented as input or platform drivers. > >> > >> The upstream standard for those sensors where the orientation matters > >> (accelerometer, gyro, compass) is IIO. > >> > >> Granted, there are other device types for which the orientation > >> information may be useful (e.g. camera). However the actual > >> interpretation and action to be taken is different for each subsystem > >> (e.g. in the camera case do the correction via V4L2_CID_HFLIP / > >> V4L2_CID_VFLIP) so I think it is better to expose it at the subsystem > >> level in a way consistent with the subsystem's ABIs. > > > > I agree that location information is used differently at different > > sub systems. But my question is why we need a new ABI ? > > > > Why not handle it in user space ? > > > > - -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
