From a92cfe1254f947c32f15ebb1f81b825076c5625e Mon Sep 17 00:00:00 2001 From: Gerd Hoffmann Date: Tue, 4 Jun 2019 07:13:41 +0100 Subject: [PATCH 6/9] usb-host: avoid libusb_set_configuration calls MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit RH-Author: Gerd Hoffmann Message-id: <20190604071341.3432-4-kraxel@redhat.com> Patchwork-id: 88477 O-Subject: [RHEL-AV-8.1.0 qemu-kvm PATCH 3/3] usb-host: avoid libusb_set_configuration calls Bugzilla: 1713679 RH-Acked-by: Philippe Mathieu-Daudé RH-Acked-by: Dr. David Alan Gilbert RH-Acked-by: Max Reitz Seems some devices become confused when we call libusb_set_configuration(). So before calling the function check whenever the device has multiple configurations in the first place, and in case it hasn't (which is the case for the majority of devices) simply skip the call as it will have no effect anyway. Signed-off-by: Gerd Hoffmann Message-id: 20190522094702.17619-4-kraxel@redhat.com (cherry picked from commit bfe44898848614cfcb3a269bc965afbe1f0f331c) Signed-off-by: Danilo C. L. de Paula --- hw/usb/host-libusb.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) diff --git a/hw/usb/host-libusb.c b/hw/usb/host-libusb.c index 4e9a45a..4f765d7 100644 --- a/hw/usb/host-libusb.c +++ b/hw/usb/host-libusb.c @@ -1225,19 +1225,21 @@ static void usb_host_set_address(USBHostDevice *s, int addr) static void usb_host_set_config(USBHostDevice *s, int config, USBPacket *p) { - int rc; + int rc = 0; trace_usb_host_set_config(s->bus_num, s->addr, config); usb_host_release_interfaces(s); - rc = libusb_set_configuration(s->dh, config); - if (rc != 0) { - usb_host_libusb_error("libusb_set_configuration", rc); - p->status = USB_RET_STALL; - if (rc == LIBUSB_ERROR_NO_DEVICE) { - usb_host_nodev(s); + if (s->ddesc.bNumConfigurations != 1) { + rc = libusb_set_configuration(s->dh, config); + if (rc != 0) { + usb_host_libusb_error("libusb_set_configuration", rc); + p->status = USB_RET_STALL; + if (rc == LIBUSB_ERROR_NO_DEVICE) { + usb_host_nodev(s); + } + return; } - return; } p->status = usb_host_claim_interfaces(s, config); if (p->status != USB_RET_SUCCESS) { -- 1.8.3.1