diff options
| author | Bjørn Mork <bjorn@mork.no> | 2016-03-03 22:20:53 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-04-20 15:41:59 +0900 |
| commit | 3aaa64b61a787d0aedc5c3fe36102419fc4eeb93 (patch) | |
| tree | ad3439adb1eff67920c4f9496ffc769992c94a40 /drivers/net | |
| parent | 32cb6781a96f24287a7b3c8716f47b0e8768709d (diff) | |
cdc_ncm: toggle altsetting to force reset before setup
[ Upstream commit 48906f62c96cc2cd35753e59310cb70eb08cc6a5 ]
Some devices will silently fail setup unless they are reset first.
This is necessary even if the data interface is already in
altsetting 0, which it will be when the device is probed for the
first time. Briefly toggling the altsetting forces a function
reset regardless of the initial state.
This fixes a setup problem observed on a number of Huawei devices,
appearing to operate in NTB-32 mode even if we explicitly set them
to NTB-16 mode.
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/net')
| -rw-r--r-- | drivers/net/usb/cdc_ncm.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/net/usb/cdc_ncm.c b/drivers/net/usb/cdc_ncm.c index e8a1144c5a8b..8c2bb77db049 100644 --- a/drivers/net/usb/cdc_ncm.c +++ b/drivers/net/usb/cdc_ncm.c @@ -794,7 +794,11 @@ int cdc_ncm_bind_common(struct usbnet *dev, struct usb_interface *intf, u8 data_ iface_no = ctx->data->cur_altsetting->desc.bInterfaceNumber; - /* reset data interface */ + /* Reset data interface. Some devices will not reset properly + * unless they are configured first. Toggle the altsetting to + * force a reset + */ + usb_set_interface(dev->udev, iface_no, data_altsetting); temp = usb_set_interface(dev->udev, iface_no, 0); if (temp) { dev_dbg(&intf->dev, "set interface failed\n"); |