From 5af35d7feccaa7d26b72c6c3d14116421d736b36 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Tue, 8 Oct 2013 21:58:06 +0200 Subject: usb-host-libusb: Fix reset handling The guest will issue an initial device reset when the device is attached, but since the current usb-host-libusb code only actually does the reset when udev->configuration != 0, and on attach the device is not yet configured, the reset gets ignored. This means that the device gets passed to the guest in an unknown state, which is not good. The udev->configuration check is there because of the release / claim interfaces done around the libusb_device_reset call, but these are not necessary. If interfaces are claimed when libusb_device_reset gets called libusb will release + reclaim them itself. The usb_host_ep_update call also is not necessary. If the reset succeeds the original config and interface alt settings will be restored. Last if the reset fails, that means the device has either disconnected or morphed into an another device and has been completely re-enumerated, so it is treated by the host as a new device and our handle is invalid, so on reset failure we need to call usb_host_nodev(). Signed-off-by: Hans de Goede Signed-off-by: Gerd Hoffmann --- hw/usb/host-libusb.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) (limited to 'hw/usb/host-libusb.c') diff --git a/hw/usb/host-libusb.c b/hw/usb/host-libusb.c index 128955dd92..428c7c5ef8 100644 --- a/hw/usb/host-libusb.c +++ b/hw/usb/host-libusb.c @@ -1256,16 +1256,14 @@ static void usb_host_flush_ep_queue(USBDevice *dev, USBEndpoint *ep) static void usb_host_handle_reset(USBDevice *udev) { USBHostDevice *s = USB_HOST_DEVICE(udev); + int rc; trace_usb_host_reset(s->bus_num, s->addr); - if (udev->configuration == 0) { - return; + rc = libusb_reset_device(s->dh); + if (rc != 0) { + usb_host_nodev(s); } - usb_host_release_interfaces(s); - libusb_reset_device(s->dh); - usb_host_claim_interfaces(s, 0); - usb_host_ep_update(s); } /* -- cgit 1.4.1 From 1294ca797c6bee39d4dbc3e92010873ce4047e0e Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Tue, 8 Oct 2013 21:58:07 +0200 Subject: usb-host-libusb: Configuration 0 may be a valid configuration Quoting from: linux/Documentation/ABI/stable/sysfs-bus-usb: Note that some devices, in violation of the USB spec, have a configuration with a value equal to 0. Writing 0 to bConfigurationValue for these devices will install that configuration, rather then unconfigure the device. So don't compare the configuration value against 0 to check for unconfigured devices, instead check for a LIBUSB_ERROR_NOT_FOUND return from libusb_get_active_config_descriptor(). Signed-off-by: Hans de Goede Signed-off-by: Gerd Hoffmann --- hw/usb/host-libusb.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) (limited to 'hw/usb/host-libusb.c') diff --git a/hw/usb/host-libusb.c b/hw/usb/host-libusb.c index 428c7c5ef8..35bae55e3a 100644 --- a/hw/usb/host-libusb.c +++ b/hw/usb/host-libusb.c @@ -992,15 +992,14 @@ static int usb_host_claim_interfaces(USBHostDevice *s, int configuration) udev->ninterfaces = 0; udev->configuration = 0; - if (configuration == 0) { - /* address state - ignore */ - return USB_RET_SUCCESS; - } - usb_host_detach_kernel(s); rc = libusb_get_active_config_descriptor(s->dev, &conf); if (rc != 0) { + if (rc == LIBUSB_ERROR_NOT_FOUND) { + /* address state - ignore */ + return USB_RET_SUCCESS; + } return USB_RET_STALL; } -- cgit 1.4.1 From f34d5c750897abb3853910ce73f63d88d74dc827 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Tue, 8 Oct 2013 21:58:08 +0200 Subject: usb-host-libusb: Detach kernel drivers earlier If we detach the kernel drivers on the first set_config, then they will be still attached when the device gets its initial reset. Causing the drivers to re-initialize the device after the reset, dirtying the device state. Signed-off-by: Hans de Goede Signed-off-by: Gerd Hoffmann --- hw/usb/host-libusb.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'hw/usb/host-libusb.c') diff --git a/hw/usb/host-libusb.c b/hw/usb/host-libusb.c index 35bae55e3a..fd320cd8aa 100644 --- a/hw/usb/host-libusb.c +++ b/hw/usb/host-libusb.c @@ -137,6 +137,7 @@ static QTAILQ_HEAD(, USBHostDevice) hostdevs = static void usb_host_auto_check(void *unused); static void usb_host_release_interfaces(USBHostDevice *s); static void usb_host_nodev(USBHostDevice *s); +static void usb_host_detach_kernel(USBHostDevice *s); static void usb_host_attach_kernel(USBHostDevice *s); /* ------------------------------------------------------------------------ */ @@ -787,10 +788,13 @@ static int usb_host_open(USBHostDevice *s, libusb_device *dev) goto fail; } - libusb_get_device_descriptor(dev, &s->ddesc); s->dev = dev; s->bus_num = bus_num; s->addr = addr; + + usb_host_detach_kernel(s); + + libusb_get_device_descriptor(dev, &s->ddesc); usb_host_get_port(s->dev, s->port, sizeof(s->port)); usb_ep_init(udev); @@ -1051,7 +1055,6 @@ static void usb_host_set_config(USBHostDevice *s, int config, USBPacket *p) trace_usb_host_set_config(s->bus_num, s->addr, config); usb_host_release_interfaces(s); - usb_host_detach_kernel(s); rc = libusb_set_configuration(s->dh, config); if (rc != 0) { usb_host_libusb_error("libusb_set_configuration", rc); -- cgit 1.4.1