On Mon, 14 Dec 2020 01:44:20 +0530 Puranjay Mohan <puranjay12@xxxxxxxxx> wrote: > On Sun, Dec 13, 2020 at 10:20 PM Jonathan Cameron <jic23@xxxxxxxxxx> wrote: > > > > On Sun, 13 Dec 2020 08:08:26 -0800 > > Guenter Roeck <linux@xxxxxxxxxxxx> wrote: > > > > > On 12/13/20 7:12 AM, Jonathan Cameron wrote: > > > > On Wed, 9 Dec 2020 11:48:40 -0800 > > > > Guenter Roeck <linux@xxxxxxxxxxxx> wrote: > > > > > > > >> On 12/9/20 12:11 AM, Alexandru Ardelean wrote: > > > >>> On Tue, Dec 8, 2020 at 6:10 PM Puranjay Mohan <puranjay12@xxxxxxxxx> wrote: > > > >>>> > > > >>>> I have this TI's TMP117 sensor with me and I was thinking about writing an > > > >>>> IIO driver for it as a hobby project. Is the IIO subsystem the correct > > > >>>> place for this driver? if yes, can someone help me get started with this, > > > >>>> I haven't written an IIO driver before. I have this sensor and also a > > > >>>> raspberry pi with me for testing. > > > >>> > > > >>> This could also fit into drivers/hwmon. > > > >>> Looking at the HWMON subsystem there are more TMP drivers there > > > >>> (TMP102/103/108/401/513). > > > >>> The first 3 seem a bit more similar to TMP117 (in terms of register map). > > > >>> > > > >> > > > >> It would probably be better suited for hwmon (it has limit registers, > > > >> suggesting a common use as hardware monitoring device). > > > > It is a curious part. I suspect TI based their design for a medical grade > > > > digital thermometer chip on an existing hwmon part. > > > > > > > > The limit registers are very simple so could be supported by IIO. > > > > This sits somewhere in the middle of high end thermocouple chips which > > > > tend to be in IIO and typically lower accuracy / range hwmon parts. > > > > > > > > It's in the fuzzy borderline region so I doubt anyone would raise strong > > > > objections to which subsystem it was in. Guenter has fallen on the > > > > hwmon side of things and I'm fine with that. > > > > > > > > > > On the other side, it turns out that there is already tmp107 support > > > in iio, and tmp107 is pretty much the spi equivalent of the same chip. > > > So it really depends on the use case. If the user wants to use the iio > > > subsystem, I am fine with it. We just need to remind people that this > > > implies no or only limited hwmon support. > > > > > > [ I really need to spend the time to write a hwmon->iio bridge. > > > The iio->hwmon bridge is a bit limited - I have not been able to > > > figure out how to support limit registers (or event values) > > > and events, and I don't think it is possible. ] > > > > So far IIO doesn't have an in kernel consumer interface for > > events. It shouldn't be that hard to add one though and it > > has been on the todo list for a very long time. We've discussed > > it a few times and concluded that there are some short cuts such > > as sending all events to all consumers and relying on the receiver > > to do any necessary filtering. It's a bit messy but it makes for > > much simpler core code. > > > > Maybe I'll get bored enough over xmas to look at it... > > > > Hi Jonathan, > Where can I access this TODO list, I would like to do some tasks on it. > I am a novice but I might be able to solve the easier tasks. Sadly I'm rubbish at keeping an up to date list. So this tends to be scattered across numerous ancient discussions. I do occasionally send out such a document, though I haven't done so for some time. I'll see if I can do a refresh sometime in next month or so. Thanks, Jonathan > > > Jonathan > > > > > > > > Guenter > > > > > > > Jonathan > > > > > > > >> > > > >>> Let's see what others have to add. > > > >>> But, all-in-all whatever driver you end up writing, the easiest method > > > >>> is to copy an existing similar driver and extend it. > > > >>> Sometimes, a part can be added to an existing driver. > > > >>> At a quick scan through existing drivers, it doesn't look like TMP117 > > > >>> is similar to existing drivers, so it may require a new driver > > > >>> altogether. > > > >> > > > >> I don't see an immediate match either, but the tmp102 hwmon driver > > > >> might be a good start. > > > >> > > > >> Guenter > > > >> > > > >>> I may have missed something though. > > > >>> > > > >>> Thanks > > > >>> Alex > > > >>> > > > >>>> > > > >>>> -- > > > >>>> Thanks and Regards > > > >>>> > > > >>>> Yours Truly, > > > >>>> > > > >>>> Puranjay Mohan > > > >> > > > > > > > > > > >
