[PATCH] IIO: Add basic MXS LRADC driver

[Juergen Beisert]

Hi Marek,

Marek Vasut wrote:
> > > > When I try to compile
> > > > your code I get:
> > > >
> > > > drivers/staging/iio/adc/mxs-lradc.c:42:40: fatal error:
> > > > linux/iio/triggered_buffer.h: No such file or directory
> > >
> > > You need this patches:
> > >     iio:kfifo_buf Take advantage of the fixed record size used in IIO
> > >     iio: kfifo - add poll support.
> > >
> > > And use latest -next.
> >
> > Thanks for the hints. Now it compiles and the driver seems to work.
> >
> > One thing I do not understand: It does not matter what channel I read
> > ('in_voltage*_raw'), only interrupt 16 ('mxs-lradc-channel0') counts up.
> > Intended?
> > Or did I a mistake by adding interrupt numbers "<13 14 15 16 17 18 19 20
> > 21 22 23 24 25>" to the corresponding device tree entry?
>
> They're wrong
>
> lradc at 80050000 {
>         compatible = "fsl,imx28-lradc";
>         reg = <0x80050000 2000>;
>         interrupts = <10 14 15 16 17 18 19
>                         20 21 22 23 24 25>;
>         status = "disabled";
> };

Ups, thanks. But still the same behaviour:

$ cat /proc/interrupts
[...]
 10:          0         -  mxs-lradc-touchscreen
 14:          0         -  mxs-lradc-thresh0
 15:          0         -  mxs-lradc-thresh1
 16:          0         -  mxs-lradc-channel0
 17:          0         -  mxs-lradc-channel1
 18:          0         -  mxs-lradc-channel2
 19:          0         -  mxs-lradc-channel3
 20:          0         -  mxs-lradc-channel4
 21:          0         -  mxs-lradc-channel5
 22:          0         -  mxs-lradc-channel6
 23:          0         -  mxs-lradc-channel7
 24:          0         -  mxs-lradc-button0
 25:          0         -  mxs-lradc-button1
[...]

$ cat in_voltage0_raw
524
$ cat in_voltage1_raw
96
$ cat in_voltage2_raw
1261

$ cat /proc/interrupts
[...]
 10:          0         -  mxs-lradc-touchscreen
 14:          0         -  mxs-lradc-thresh0
 15:          0         -  mxs-lradc-thresh1
 16:          3         -  mxs-lradc-channel0
 17:          0         -  mxs-lradc-channel1
 18:          0         -  mxs-lradc-channel2
 19:          0         -  mxs-lradc-channel3
 20:          0         -  mxs-lradc-channel4
 21:          0         -  mxs-lradc-channel5
 22:          0         -  mxs-lradc-channel6
 23:          0         -  mxs-lradc-channel7
 24:          0         -  mxs-lradc-button0
 25:          0         -  mxs-lradc-button1
[...]

Intended in this way?

Regards,
Juergen

-- 
Pengutronix e.K.                              | Juergen Beisert             |
Linux Solutions for Science and Industry      | http://www.pengutronix.de/  |