shithub: riscv

Info  •  Files  •  Log  •  Branches

nusb/kb: add quirks for Elecom HUGE trackball

As said in the code comment:

	Elecom trackball report descriptor lies by
	omission, failing to mention all its buttons.
	We patch the descriptor with a correct count
	which lets us parse full reports. Tested with:
		Elecom HUGE (M-HT1DRBK, M-HT1URBK)

The descriptor fixup is adapted from Linux kernel:
	drivers/hid/hid-elecom.c
in which a more detailed account of why and how this
works may be found.

A followup change to nusb/kb will be needed to expose
these additional events for potential remapping.

--- a/sys/src/cmd/nusb/kb/kb.c

+++ b/sys/src/cmd/nusb/kb/kb.c

@@ -836,6 +836,33 @@

 }

 static void

+quirks(Hiddev *f)

+{

+	Dev *d;

+	

+	d = f->dev;

+	

+	/* Elecom trackball report descriptor lies by

+	 * omission, failing to mention all its buttons.

+	 * We patch the descriptor with a correct count

+	 * which lets us parse full reports. Tested with:

+	 *   Elecom HUGE (M-HT1DRBK, M-HT1URBK) */

+	if(d->usb->vid == 0x056e && d->usb->did == 0x010c){

+		if(f->nrep < 32

+		|| f->rep[12] != 0x95

+		|| f->rep[14] != 0x75

+		|| f->rep[15] != 0x01

+		|| f->rep[20] != 0x29

+		|| f->rep[30] != 0x75)

+		return;

+

+		f->rep[13] = 8;

+		f->rep[21] = 8;

+		f->rep[31] = 0;

+	}

+}

+

+static void

 hdsetup(Dev *d, Ep *ep)

 {

 	Hiddev *f;

@@ -858,6 +885,7 @@

 		fprint(2, "%s: %s: opendevdata: %r\n", argv0, f->ep->dir);

 		goto Err;

 	}

+	quirks(f);

 	procrfork(readerproc, f, Stack, RFNOTEG);

 	return;

 Err: