Re: [PATCH] HID: sensor-hub: Enable hid core report processing for all devices

[srinivas pandruvada <srinivas.pandruvada@linux.intel.com>]

On Fri, 2023-12-22 at 14:28 +0100, Benjamin Tissoires wrote:
> On Fri, Dec 22, 2023 at 1:44 PM srinivas pandruvada
> <srinivas.pandruvada@linux.intel.com> wrote:
> > 
> > On Wed, 2023-12-20 at 17:04 +0200, Yauhen Kharuzhy wrote:
> > > ср, 20 дек. 2023 г. в 16:52, Jonathan Cameron <jic23@kernel.org>:
> > > > 
> > > > On Wed, 20 Dec 2023 01:15:03 +0200
> > > > Yauhen Kharuzhy <jekhor@gmail.com> wrote:
> > > > 
> > > > > After the commit 666cf30a589a ("HID: sensor-hub: Allow multi-
> > > > > function
> > > > > sensor devices") hub devices are claimed by hidraw driver in
> > > > > hid_connect().
> > > > > This causes stoppping of processing HID reports by hid core
> > > > > due
> > > > > to
> > > > > optimization.
> > > > > 
> > > > > In such case, the hid-sensor-custom driver cannot match a
> > > > > known
> > > > > custom
> > > > > sensor in hid_sensor_custom_get_known() because it try to
> > > > > check
> > > > > custom
> > > > > properties which weren't filled from the report because hid
> > > > > core
> > > > > didn't
> > > > > parsed it.
> > > > > 
> > > > > As result, custom sensors like hinge angle sensor and LISS
> > > > > sensors
> > > > > don't work.
> > > > > 
> > > > > Mark the sensor hub devices claimed by some driver to avoid
> > > > > hidraw-related
> > > > > optimizations.
> > > > > 
> > > > > Signed-off-by: Yauhen Kharuzhy <jekhor@gmail.com>
> > > > Fixes tag?
> > > 
> > > Fixes: 666cf30a589a ("HID: sensor-hub: Allow multi-function
> > > sensor
> > > devices")
> > > 
> > This flag causes
> >                 hdev->claimed |= HID_CLAIMED_DRIVER;
> > I don't see the flag is used anywhere after this assignment in hid
> > core. Only two other drivers are setting this flag. We need Jiri's
> > help
> > here why this is a special case.
> 
> It's used in hid_report_raw_event()[0]:
> ```
>     if (hid->claimed != HID_CLAIMED_HIDRAW && report->maxfield) {
>         hid_process_report(hid, report, cdata, interrupt);
>         hdrv = hid->driver;
>         if (hdrv && hdrv->report)
>             hdrv->report(hid, report);
>     }
> ```
> 
> The whole point of setting HID_CLAIMED_DRIVER is to have hid->claimed
> not equal to HID_CLAIMED_HIDRAW, in case we need the hid core
> processing.
Thanks Benjamin for explaining.
Then this change looks fine as sensor hub driver will claim this device
and it needs hid core to process report.

Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>

Thanks,
Srinivas

> 
> Cheers,
> Benjamin
> 
> 
> [0]
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/hid/hid-core.c#n2015
> 
> > 
> > Thanks,
> > Srinivas
> > 
> > > > 
> > > > > ---
> > > > >  drivers/hid/hid-sensor-hub.c | 2 +-
> > > > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > > > > 
> > > > > diff --git a/drivers/hid/hid-sensor-hub.c b/drivers/hid/hid-
> > > > > sensor-hub.c
> > > > > index 2eba152e8b90..26e93a331a51 100644
> > > > > --- a/drivers/hid/hid-sensor-hub.c
> > > > > +++ b/drivers/hid/hid-sensor-hub.c
> > > > > @@ -632,7 +632,7 @@ static int sensor_hub_probe(struct
> > > > > hid_device
> > > > > *hdev,
> > > > >       }
> > > > >       INIT_LIST_HEAD(&hdev->inputs);
> > > > > 
> > > > > -     ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
> > > > > +     ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT |
> > > > > HID_CONNECT_DRIVER);
> > > > >       if (ret) {
> > > > >               hid_err(hdev, "hw start failed\n");
> > > > >               return ret;
> > > > 
> > > 
> > > 
> > 
>