Re: [PATCH v2] usb: serial: qcserial: add EM9191 support

[Reinhard Speyerer <rspmn@arcor.de>]

On Fri, Jul 15, 2022 at 11:56:23AM +0200, Frans Klaver wrote:
> From: Frans Klaver <frans.klaver@vislink.com>
> 
> Support for QDL mode is already present for EM9191 modules, but the
> non-QDL mode appears to be missing. Add it now.
> 
> T:  Bus=03 Lev=03 Prnt=04 Port=01 Cnt=02 Dev#= 17 Spd=480 MxCh= 0
> D:  Ver= 2.10 Cls=00(>ifc ) Sub=00 Prot=00 MxPS=64 #Cfgs=  1
> P:  Vendor=1199 ProdID=90d3 Rev=00.06
> S:  Manufacturer=Sierra Wireless, Incorporated
> S:  Product=Sierra Wireless EM9191
> S:  SerialNumber=8W0463003002A114
> C:  #Ifs= 4 Cfg#= 1 Atr=a0 MxPwr=500mA
> I:  If#=0x0 Alt= 0 #EPs= 1 Cls=02(commc) Sub=0e Prot=00 Driver=cdc_mbim
> I:  If#=0x1 Alt= 1 #EPs= 2 Cls=0a(data ) Sub=00 Prot=02 Driver=cdc_mbim
> I:  If#=0x3 Alt= 0 #EPs= 3 Cls=ff(vend.) Sub=00 Prot=00 Driver=qcserial
> I:  If#=0x4 Alt= 0 #EPs= 2 Cls=ff(vend.) Sub=ff Prot=30 Driver=qcserial
> 
> Cc: stable@vger.kernel.org
> Signed-off-by: Frans Klaver <frans.klaver@vislink.com>
> ---
> I noticed an e-mail address discrepancy that git-send-email didn't
> magically fix for me. No change otherwise.
> 
>  drivers/usb/serial/qcserial.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/usb/serial/qcserial.c b/drivers/usb/serial/qcserial.c
> index 586ef5551e76e..73f6d3a37c0c4 100644
> --- a/drivers/usb/serial/qcserial.c
> +++ b/drivers/usb/serial/qcserial.c
> @@ -166,6 +166,7 @@ static const struct usb_device_id id_table[] = {
>  	{DEVICE_SWI(0x1199, 0x9090)},	/* Sierra Wireless EM7565 QDL */
>  	{DEVICE_SWI(0x1199, 0x9091)},	/* Sierra Wireless EM7565 */
>  	{DEVICE_SWI(0x1199, 0x90d2)},	/* Sierra Wireless EM9191 QDL */
> +	{DEVICE_SWI(0x1199, 0x90d3)},	/* Sierra Wireless EM9191 */
>  	{DEVICE_SWI(0x1199, 0xc080)},	/* Sierra Wireless EM7590 QDL */
>  	{DEVICE_SWI(0x1199, 0xc081)},	/* Sierra Wireless EM7590 */
>  	{DEVICE_SWI(0x413c, 0x81a2)},	/* Dell Wireless 5806 Gobi(TM) 4G LTE Mobile Broadband Card */

Hi Frans,

the qcserial driver used in the usb-devices output above does not seem
to be built from the mainline qcserial.c with your patch applied as USB
interface 4 is ignored by the QCSERIAL_SWI layout.

To avoid potential side effects in case Sierra Wireless adds a vendor class
USB interface 2 not intended to be used with qcserial.c it might be best
to use a new QCSERIAL_SWI2 layout similar to what has been done in
their MBPL drivers mentioned here
https://forum.sierrawireless.com/t/rc7620-and-linux-driver/24308/ .

Regards,
Reinhard