Messages in this thread |  | | Date | Thu, 21 Jan 2021 11:23:56 +0100 | From | Johan Hovold <> | Subject | Re: [PATCH v5 3/3] usb: cdc-acm: Ignore Exar XR21V141X when serial driver is built |
| |
On Sun, Nov 22, 2020 at 10:38:22PM +0530, Manivannan Sadhasivam wrote: > From: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> > > The RTS/CTS line discipline for this device doesn't follow > the standard. So, in order to properly support TX, a separate > driver is needed.
This took a bit of effort to understand, but I think I know what you're referring to now. In ACM mode the device has RTS/CTS flow control enabled, which means TX will be disabled in case CTS isn't wired up correctly.
It as nothing to do with line disciplines though.
> Ensure that cdc_acm will ignore it during probe time, if the > Kernel is built with support for it. > > Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org> > Signed-off-by: Manivannan Sadhasivam <mani@kernel.org>
> --- > drivers/usb/class/cdc-acm.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c > index 30ef946a8e1a..719829e6b6db 100644 > --- a/drivers/usb/class/cdc-acm.c > +++ b/drivers/usb/class/cdc-acm.c > @@ -1890,6 +1890,12 @@ static const struct usb_device_id acm_ids[] = { > }, > #endif > > +#if IS_ENABLED(CONFIG_USB_SERIAL_XR) > + { USB_DEVICE(0x04e2, 0x1410), /* Ignore XR21V141X USB to Serial converter */ > + .driver_info = IGNORE_DEVICE, > + }, > +#endif > + > /*Samsung phone in firmware update mode */ > { USB_DEVICE(0x04e8, 0x685d), > .driver_info = IGNORE_DEVICE,
I've rewritten the commit message and applied this one now.
Johan
|  |