Re: [PATCH] HID: quirks: Add no_init_reports for AKAI midi controller

[Stafford Horne]

On Thu, 28 Jan 2016, Oliver Neukum wrote:

> On Wed, 2016-01-27 at 22:31 +0100, Jiri Kosina wrote:
> > On Wed, 27 Jan 2016, Stafford Horne wrote:
> >
> > > The midi controller times-out while initializing reports, this
> > > causes boot to take an extra 10 seconds. The device descriptor
> > > advertises that it has an internal HID device but seems to not
> > > actually do anything useful.
> > >
> > > Signed-off-by: Stafford Horne <shorne@xxxxxxxxx>
> > > ---
> > >  drivers/hid/hid-ids.h           | 3 +++
> > >  drivers/hid/usbhid/hid-quirks.c | 1 +
> > >  2 files changed, 4 insertions(+)
> > >
> > > diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
> > > index b6ff6e7..3dfb166 100644
> > > --- a/drivers/hid/hid-ids.h
> > > +++ b/drivers/hid/hid-ids.h
> > > @@ -61,6 +61,9 @@
> > >  #define USB_VENDOR_ID_AIREN		0x1a2c
> > >  #define USB_DEVICE_ID_AIREN_SLIMPLUS	0x0002
> > >
> > > +#define USB_VENDOR_ID_AKAI              0x2011
> > > +#define USB_DEVICE_ID_AKAI_MPKMINI2     0x0715
> > > +
> > >  #define USB_VENDOR_ID_ALCOR		0x058f
> > >  #define USB_DEVICE_ID_ALCOR_USBRS232	0x9720
> > >
> > > diff --git a/drivers/hid/usbhid/hid-quirks.c b/drivers/hid/usbhid/hid-quirks.c
> > > index 7dd0953..055e740 100644
> > > --- a/drivers/hid/usbhid/hid-quirks.c
> > > +++ b/drivers/hid/usbhid/hid-quirks.c
> > > @@ -55,6 +55,7 @@ static const struct hid_blacklist {
> > >  	{ USB_VENDOR_ID_TOUCHPACK, USB_DEVICE_ID_TOUCHPACK_RTS, HID_QUIRK_MULTI_INPUT },
> > >
> > >  	{ USB_VENDOR_ID_AIREN, USB_DEVICE_ID_AIREN_SLIMPLUS, HID_QUIRK_NOGET },
> > > +	{ USB_VENDOR_ID_AKAI, USB_DEVICE_ID_AKAI_MPKMINI2, HID_QUIRK_NO_INIT_REPORTS },
> >
> > If the (proclaimed) HID device is completely silent, wouldn't
> > HID_QUIRK_IGNORE be more appropriate?
>
> If it really is impossible to use the device.
> That quirk would preclude any use you are not aware of with almost
> no added benefit. I would take the patch as is.

That may be right, after having a look at usbhid quirks, no device yet has 
HID_QUIRK_IGNORE.  Also, I have a feeling the HID enpoints might have some 
proprietary functionality.

The defined interface descriptors are 1 HID, 2 Audio Control Device, 3 Audio
MIDI streaming. I tried to write and read from the HID endpoints using 
hidraw with no luck. But someone else might figure it out.