(In reply to comment #6)
> Created an attachment (id=30134) [details]
> dmidecode output
> 
> Output of dmidecode. I'm not a guru with reading those, but it does not seem
> very useful to me. :-( There is no reference to "SD" or "card" or "storage",
> and just one USB related record which doesn't even say it's internal (well, the
> thing does have external USBs as well):
> 
> Handle 0x0008, DMI type 8, 9 bytes
> Port Connector Information
>         Internal Reference Designator: USB
>         Internal Connector Type: None
>         External Reference Designator: Not Specified
>         External Connector Type: Access Bus (USB)
>         Port Type: USB

Just for the record, see [0] from one of my boxes at home. 

Of course, I have no idea how to map USB0, USB1 to actual USB host controllers or even ports on the same host controller. It might be possible to get the kernel USB drivers to parse/interpret DMI data and then export some attributes like whether the actual USB port is external or internal.

But that's going to be a lot of work. And it might be imprecise because vendors don't properly populate DMI. And there's no guarantee the USB kernel folks are interested in this.

[0] :

Handle 0x0010, DMI type 8, 9 bytes
Port Connector Information
        Internal Reference Designator: USB0
        Internal Connector Type: None
        External Reference Designator: USB0
        External Connector Type: Access Bus (USB)
        Port Type: USB

Handle 0x0011, DMI type 8, 9 bytes
Port Connector Information
        Internal Reference Designator: USB1
        Internal Connector Type: None
        External Reference Designator: USB1
        External Connector Type: Access Bus (USB)
        Port Type: USB

Handle 0x0012, DMI type 8, 9 bytes
Port Connector Information
        Internal Reference Designator: USB2
        Internal Connector Type: None
        External Reference Designator: USB2
        External Connector Type: Access Bus (USB)
        Port Type: USB

Handle 0x0013, DMI type 8, 9 bytes
Port Connector Information
        Internal Reference Designator: USB3
        Internal Connector Type: None
        External Reference Designator: USB3
        External Connector Type: Access Bus (USB)
        Port Type: USB

[...]

Handle 0x0030, DMI type 8, 9 bytes
Port Connector Information
        Internal Reference Designator: JUSR2 - USB4/5
        Internal Connector Type: Other
        External Reference Designator: Not Specified
        External Connector Type: None
        Port Type: USB

Handle 0x0031, DMI type 8, 9 bytes
Port Connector Information
        Internal Reference Designator: JUSR3 - USB6/7
        Internal Connector Type: Other
        External Reference Designator: Not Specified
        External Connector Type: None
        Port Type: USB

Handle 0x0032, DMI type 8, 9 bytes
Port Connector Information
        Internal Reference Designator: USB8 - USB8
        Internal Connector Type: Access Bus (USB)
        External Reference Designator: Not Specified
        External Connector Type: None
        Port Type: USB

Handle 0x0033, DMI type 8, 9 bytes
Port Connector Information
        Internal Reference Designator: USB9 - USB9
        Internal Connector Type: Access Bus (USB)
        External Reference Designator: Not Specified
        External Connector Type: None
        Port Type: USB