USB: qcaux: Add Motorola modem UARTs

[Johan Hovold <johan@kernel.org>]

Hi Tony,

Sorry for the late reply.

On Thu, Dec 06, 2018 at 07:48:23AM -0800, Tony Lindgren wrote:
> Hi,
> 
> * Johan Hovold <johan@kernel.org> [181206 06:00]:
> > On Wed, Dec 05, 2018 at 05:54:07PM -0800, Tony Lindgren wrote:
 
> > Could you post the output for the two devices you have in "modem" mode?
> 
> Yes correct lsusb -v output below with five UARTs with ff/ff/ff and
> two QMI ports that are already handled with an earlier commit
> 4071898bf0f4 ("net: qmi_wwan: Add USB IDs for MDM6600 modem on
> Motorola Droid 4").

Isn't it four QMI ports even (interfaces 5 through 8)?

> > How do switch modes by the way?
> 
> The flash mode gets enabled with the control GPIOs. I just
> did a quick test patch for phy-mapphone-mdm6600 using module
> param for that. Then additionally the modem USB can be
> multiplexed to the PC by configuring mode in phy-cpcap-usb
> but I don't have a patch for that.

Ah, ok.

> 8< -----------------------
> Bus 001 Device 002: ID 22b8:2a70  
> Device Descriptor:
>   bLength                18
>   bDescriptorType         1
>   bcdUSB               2.00
>   bDeviceClass            0 
>   bDeviceSubClass         0 
>   bDeviceProtocol         0 
>   bMaxPacketSize0        64
>   idVendor           0x22b8 
>   idProduct          0x2a70 
>   bcdDevice            0.00
>   iManufacturer           1 Motorola, Incorporated
>   iProduct                2 Flash MZ600
>   iSerial                 0 
>   bNumConfigurations      1

>     Interface Descriptor:
>       bLength                 9
>       bDescriptorType         4
>       bInterfaceNumber        4
>       bAlternateSetting       0
>       bNumEndpoints           3
>       bInterfaceClass       255 
>       bInterfaceSubClass    255 
>       bInterfaceProtocol    255 
>       iInterface              0 
>       Endpoint Descriptor:
>         bLength                 7
>         bDescriptorType         5
>         bEndpointAddress     0x85  EP 5 IN
>         bmAttributes            3
>           Transfer Type            Interrupt
>           Synch Type               None
>           Usage Type               Data
>         wMaxPacketSize     0x0040  1x 64 bytes
>         bInterval               5

Since the modem (AT) port here has an interrupt endpoint, you should add
these device ids to the option driver which can handle that.

As the comment in qcaux suggests, that driver is intended for the diag
port of some old devices where the modem port was handled by cdc-acm.

>       Endpoint Descriptor:
>         bLength                 7
>         bDescriptorType         5
>         bEndpointAddress     0x86  EP 6 IN
>         bmAttributes            2
>           Transfer Type            Bulk
>           Synch Type               None
>           Usage Type               Data
>         wMaxPacketSize     0x0040  1x 64 bytes
>         bInterval              32
>       Endpoint Descriptor:
>         bLength                 7
>         bDescriptorType         5
>         bEndpointAddress     0x05  EP 5 OUT
>         bmAttributes            2
>           Transfer Type            Bulk
>           Synch Type               None
>           Usage Type               Data
>         wMaxPacketSize     0x0040  1x 64 bytes
>         bInterval              32

Also, if possible please include the more compact output of usb-devices
(or /sys/kernel/debug/usb/devices) for the devices you have access to in
the commit message.

Thanks,
Johan