>-----Original Message----- >From: Nathan Hartman <hartman.nat...@gmail.com> >Sent: 16 September 2022 12:37 > >On Fri, Sep 16, 2022 at 7:33 AM TimH <t...@jti.uk.com.invalid> wrote: > >> >From: Nathan Hartman <hartman.nat...@gmail.com> >> >Sent: 16 September 2022 12:31 >> >To: dev@nuttx.apache.org >> >Subject: Re: ADC device close and IRQ >> > >> >On Fri, Sep 16, 2022 at 7:20 AM TimH <t...@jti.uk.com.invalid> wrote: >> > >> >> Actually a little more complicated as the detach and disable in adc >> >> close then kills the touch screen driver as well (it uses the ADC). >> >> l'll figure out a way, I'm sure! >> > >> > >> > >> >I haven't looked at the code, but it sounds like any driver being >> >closed >> shuts >> >down the ADC for all drivers. >> > >> >Instead, the driver should keep a reference count. The underlying >> >hardware should be initialized when the first instance of the driver >> >is opened and >> un- >> >initialized only when the last instance of the driver is closed. >> > >> >Cheers >> >Nathan >> >> At present (by default/out of the box) there are two drivers - one for >> the TS, registered as /dev/input0, the other for the ADC, as >> /dev/adc0. There are, indeed, counts for each separate driver, but no >"cross-coupling". >> >> Perhaps the TS driver needs to be rolled into the ADC driver for this chip? > > > >If it's using the same physical hardware peripheral then they will indeed need >to be coordinated somehow, or combined. Not sure what specifically to >suggest here. > >Nathan
Since all SAMA5Dx devices provide touchscreen support using the built-in ADC there is definitely an argument to move the touchscreen code into the ADC code. It will need a Kconfig bool to enable/disable this built-in support, as there is no reason a given design might not use an external TS controller chip - the built-in ADC support is only for resistive touchscreens, so any capacitive type will still need the external device, for example.
