Hi Eric, On Thursday 12 July 2012 16:05:47 Eric Ding wrote: > On 07/09/2012 10:17 PM, Alan Stern wrote: > > On Sun, 8 Jul 2012, Jonathan Nieder wrote: > >> Eric Ding wrote: > >>> So it looks like you'd have to both look for USB_CLASS_VIDEO and check > >>> uvc_ids[] too... which becomes somewhat hairy, since I assume you don't > >>> realy want usb_detect_quirks() to reference UVC-specific structs... > >>> which brings us back to the original laundry list approach of naming > >>> several affected webcams explicitly, no? > >> > >> Why wouldn't I want usb_detect_quirks() to reference UVC-specific > >> structs? > > > > Well, it's a layering violation. Not to mention a duplication of code. > > > > But if the alternative is to list every buggy webcam made by Logitech, > > it might be worthwhile. > > So... now what, then? Who decides which is the better of two evils: > obvious code duplication vs. layering violation? FWIW, it does seem > like the number of Logitech webcams which aren't USB_CLASS_VIDEO is > finite, including only older webcams, so perhaps listing "every buggy > webcam made by Logitech" in two places (one in UVC code, one in USB core > code) is not an invitation for long-term code maintenance nightmares. I'm fine with both solutions. Handling the quirks in the USB core has my preference, as it would ensure that no race condition will cause any issue at probe time. -- Regards, Laurent Pinchart -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
