Re: [RFC PATCH 20/22] thunderbolt: Add support for USB tunnels

[Mika Westerberg]

On Thu, Oct 03, 2019 at 10:42:56AM +0200, Oliver Neukum wrote:
> Am Dienstag, den 01.10.2019, 14:38 +0300 schrieb Mika Westerberg:
> > From: Rajmohan Mani <rajmohan.mani@xxxxxxxxx>
> > 
> > USB4 added a capability to tunnel USB 3.x protocol over the USB4
> > fabric. USB4 device routers may include integrated SuperSpeed HUB or a
> > function or both. USB tunneling follows PCIe so that the tunnel is
> > created between the parent and the child router from USB downstream
> > adapter port to USB upstream adapter port over a single USB4 link.
> > 
> > This adds support for USB tunneling and also capability to discover
> > existing USB tunnels (for example created by connection manager in boot
> > firmware).
> > 
> > Signed-off-by: Rajmohan Mani <rajmohan.mani@xxxxxxxxx>
> > Co-developed-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
> > Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
> > ---
> >  drivers/thunderbolt/switch.c  |  35 ++++++++
> >  drivers/thunderbolt/tb.c      | 153 ++++++++++++++++++++++++++------
> >  drivers/thunderbolt/tb.h      |  15 ++++
> >  drivers/thunderbolt/tb_regs.h |   9 +-
> >  drivers/thunderbolt/tunnel.c  | 158 +++++++++++++++++++++++++++++++++-
> >  drivers/thunderbolt/tunnel.h  |   9 ++
> >  drivers/thunderbolt/usb4.c    |  41 ++++++++-
> >  7 files changed, 393 insertions(+), 27 deletions(-)
> > 
> > diff --git a/drivers/thunderbolt/switch.c b/drivers/thunderbolt/switch.c
> > index 58e3f54ddbb9..5a3236fefb76 100644
> > --- a/drivers/thunderbolt/switch.c
> > +++ b/drivers/thunderbolt/switch.c
> > @@ -1025,11 +1025,46 @@ bool tb_port_is_enabled(struct tb_port *port)
> >  	case TB_TYPE_DP_HDMI_OUT:
> >  		return tb_dp_port_is_enabled(port);
> >  
> > +	case TB_TYPE_USB_UP:
> > +	case TB_TYPE_USB_DOWN:
> > +		return tb_usb_port_is_enabled(port);
> > +
> >  	default:
> >  		return false;
> >  	}
> >  }
> >  
> > +/**
> > + * tb_usb_port_is_enabled() - Is the USB adapter port enabled
> > + * @port: USB port to check
> > + */
> > +bool tb_usb_port_is_enabled(struct tb_port *port)
> 
> Should these functions be called tb_usb3_port... ?
> This looks like all USB would need this.

Yes, I agree it follows the spec better that way.

> > -static const char * const tb_tunnel_names[] = { "PCI", "DP", "DMA" };
> > +static const char * const tb_tunnel_names[] = { "PCI", "DP", "DMA", "USB"};
> 
> USB3 ?

Sure.