Re: [PATCH v2 1/1] usb: gadget: f_fs: Add support for SuperSpeed Mode

[Manu Gautam <mgautam@codeaurora.org>]

Hi Felipe,

I wanted to mention one point with respect to this patch:
Below changes in the functionfs.h to add ss_count (super speed 
descriptors count) in desc_header (which is passed from userspace) make 
the driver incompatible with existing userspace applications compiled 
against old header file. Let me know if that is acceptable.
We are using this driver with Android for adbd (android debug bridge) 
and these changes are required to support adb over Super Speed 
controllers e.g. DWC3 along with changed in adbd to pass SS EP and 
companion descriptors.

Regards,
Manu

On 9/20/2013 5:25 PM, Manu Gautam wrote:
> diff --git a/include/uapi/linux/usb/functionfs.h b/include/uapi/linux/usb/functionfs.h
> index d6b0128..d6940d7 100644
> --- a/include/uapi/linux/usb/functionfs.h
> +++ b/include/uapi/linux/usb/functionfs.h
> @@ -37,6 +37,7 @@ struct usb_functionfs_descs_head {
>   	__le32 length;
>   	__le32 fs_count;
>   	__le32 hs_count;
> +	__le32 ss_count;
>   } __attribute__((packed));
>   
>   /*
> @@ -48,8 +49,10 @@ struct usb_functionfs_descs_head {
>    * |   4 | length    | LE32         | length of the whole data chunk       |
>    * |   8 | fs_count  | LE32         | number of full-speed descriptors     |
>    * |  12 | hs_count  | LE32         | number of high-speed descriptors     |
> - * |  16 | fs_descrs | Descriptor[] | list of full-speed descriptors       |
> + * |  16 | ss_count  | LE32         | number of super-speed descriptors    |
> + * |  20 | fs_descrs | Descriptor[] | list of full-speed descriptors       |
>    * |     | hs_descrs | Descriptor[] | list of high-speed descriptors       |
> + * |     | ss_descrs | Descriptor[] | list of super-speed descriptors      |