From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38694) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1avAXD-000114-H1 for qemu-devel@nongnu.org; Tue, 26 Apr 2016 17:28:44 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1avAXA-0002Hs-7t for qemu-devel@nongnu.org; Tue, 26 Apr 2016 17:28:43 -0400 Received: from mx1.redhat.com ([209.132.183.28]:35418) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1avAXA-0002Hf-2g for qemu-devel@nongnu.org; Tue, 26 Apr 2016 17:28:40 -0400 From: Bandan Das References: <1460892593-5908-1-git-send-email-109lozanoi@gmail.com> <20160426091156.GA10650@stefanha-x1.localdomain> Date: Tue, 26 Apr 2016 17:28:37 -0400 In-Reply-To: <20160426091156.GA10650@stefanha-x1.localdomain> (Stefan Hajnoczi's message of "Tue, 26 Apr 2016 10:11:56 +0100") Message-ID: MIME-Version: 1.0 Content-Type: text/plain Subject: Re: [Qemu-devel] [PATCH] usb-mtp: fix usb_mtp_get_device_info so that libmtp on the guest doesn't complain List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Stefan Hajnoczi Cc: Isaac Lozano <109lozanoi@gmail.com>, qemu-devel@nongnu.org, kraxel@redhat.com Stefan Hajnoczi writes: > On Sun, Apr 17, 2016 at 04:29:53AM -0700, Isaac Lozano wrote: >> If an application uses libmtp on the guest system, >> it will complain with the warning message: >> LIBMTP WARNING: VendorExtensionID: ffffffff >> LIBMTP WARNING: VendorExtensionDesc: (null) >> LIBMTP WARNING: this typically means the device is PTP (i.e. a camera) but >> not a MTP device at all. Trying to continue anyway. >> >> This is because libmtp expects a MTP Vendor Extension ID of 0x00000006 and a >> MTP Version of 0x0064. These numbers are taken from Microsoft's MTP Vendor >> Extension Identification Message page and are what most physical devices >> show. >> >> Signed-off-by: Isaac Lozano <109lozanoi@gmail.com> >> --- >> hw/usb/dev-mtp.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) > > Welcome to QEMU! > > Link to MTP Vendor Extension Identification Message page for other > reviewers: > https://msdn.microsoft.com/en-us/library/ff632482.aspx I am confused why the MTP spec on usb.org specifies in 5.1.1.2 that this value should be 0xffffffff for MTP devices. Is it just not updated or there are similar MS specific differences to watch out for ? Either way, it seems libmtp will always be a good reference when we are stuck with such discrepencies. > Reviewed-by: Stefan Hajnoczi