Hi Mauro, On Fri, Jun 05, 2020 at 01:13:55PM +0200, Mauro Carvalho Chehab wrote: > Em Fri, 1 May 2020 00:19:22 +0530 > mani@xxxxxxxxxx escreveu: > > > From: Manivannan Sadhasivam <mani@xxxxxxxxxx> > > > > Hello, > > > > This series adds support for MaxLinear/Exar USB to serial converters. > > This driver only supports XR21V141X series but it can easily be extended > > to other series in future. > > > > This driver is inspired from the initial one submitted by Patong Yang: > > > > https://patchwork.kernel.org/patch/10543261/ > > > > While the initial driver was a custom tty USB driver exposing whole > > new serial interface ttyXRUSBn, this version is completely based on USB > > serial core thus exposing the interfaces as ttyUSBn. This will avoid > > the overhead of exposing a new USB serial interface which the userspace > > tools are unaware of. > > Hmm... I guess you also need the enclosed patch, to ensure that cdc_acm > won't try to hijack it, when the Kernel is built with both drivers. > Ah right. I will include this patch in next iteration. Many thanks! Regards, Mani > Thanks, > Mauro > > [PATCH] usb: cdc-acm: ignore Exar XR21V141X when serial driver is > built > > 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. > > 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@xxxxxxxxxx> > > diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c > index ded8d93834ca..f87288834ded 100644 > --- a/drivers/usb/class/cdc-acm.c > +++ b/drivers/usb/class/cdc-acm.c > @@ -1889,7 +1889,11 @@ static const struct usb_device_id acm_ids[] = { > .driver_info = IGNORE_DEVICE, > }, > #endif > - > +#if IS_ENABLED(CONFIG_USB_SERIAL_XR) > + { USB_DEVICE(0x04e2, 0x1410), /* XR21V141X uses a different rts/cts discipline */ > + .driver_info = IGNORE_DEVICE, > + }, > +#endif > /*Samsung phone in firmware update mode */ > { USB_DEVICE(0x04e8, 0x685d), > .driver_info = IGNORE_DEVICE, >
