From bfe44898848614cfcb3a269bc965afbe1f0f331c Mon Sep 17 00:00:00 2001 From: Gerd Hoffmann Date: Wed, 22 May 2019 11:47:02 +0200 Subject: usb-host: avoid libusb_set_configuration calls 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 --- hw/usb/host-libusb.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) (limited to 'hw') 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) { -- cgit v1.1