Re: [PATCH] thunderbolt: Add DP out resource when DP tunnel is discovered.

[Greg KH <gregkh@linuxfoundation.org>]

On Thu, Jul 07, 2022 at 04:01:12PM +0530, Sanjay R Mehta wrote:
> 
> 
> On 7/6/2022 5:30 PM, Sanjay R Mehta wrote:
> > 
> > 
> > On 7/6/2022 11:55 AM, Greg KH wrote:
> >> On Wed, Jul 06, 2022 at 12:39:38AM -0500, Sanjay R Mehta wrote:
> >>> From: Sanjay R Mehta <sanju.mehta@amd.com>
> >>>
> >>> If the boot firmware implements a connection manager of its
> >>> own it may create a DP tunnel and will be handed off to Linux
> >>> CM, but the DP out resource is not saved in the dp_resource
> >>> list.
> >>>
> >>> This patch adds tunnelled DP out port to the dp_resource list
> >>> once the DP tunnel is discovered.
> >>>
> >>> Signed-off-by: Sanjay R Mehta <sanju.mehta@amd.com>
> >>> Signed-off-by: Basavaraj Natikar <Basavaraj.Natikar@amd.com>
> >>> ---
> >>>  drivers/thunderbolt/tb.c     | 15 +++++++++++++++
> >>>  drivers/thunderbolt/tb.h     |  1 +
> >>>  drivers/thunderbolt/tunnel.c |  2 ++
> >>>  3 files changed, 18 insertions(+)
> >>>
> >>> diff --git a/drivers/thunderbolt/tb.c b/drivers/thunderbolt/tb.c
> >>> index 9a3214f..dcd0c3e 100644
> >>> --- a/drivers/thunderbolt/tb.c
> >>> +++ b/drivers/thunderbolt/tb.c
> >>> @@ -1006,6 +1006,21 @@ static void tb_dp_resource_unavailable(struct tb *tb, struct tb_port *port)
> >>>  	tb_tunnel_dp(tb);
> >>>  }
> >>>  
> >>> +void tb_dp_resource_available_discovered(struct tb *tb, struct tb_port *port)
> >>> +{
> >>> +	struct tb_cm *tcm = tb_priv(tb);
> >>> +	struct tb_port *p;
> >>> +
> >>> +	list_for_each_entry(p, &tcm->dp_resources, list) {
> >>> +		if (p == port)
> >>> +			return;
> >>> +	}
> >>> +
> >>> +	tb_port_dbg(port, "DP %s resource available discovered\n",
> >>> +		    tb_port_is_dpin(port) ? "IN" : "OUT");
> >>> +	list_add_tail(&port->list, &tcm->dp_resources);
> >>> +}
> >>> +
> >>>  static void tb_dp_resource_available(struct tb *tb, struct tb_port *port)
> >>>  {
> >>>  	struct tb_cm *tcm = tb_priv(tb);
> >>> diff --git a/drivers/thunderbolt/tb.h b/drivers/thunderbolt/tb.h
> >>> index 4602c69..cef2fe3 100644
> >>> --- a/drivers/thunderbolt/tb.h
> >>> +++ b/drivers/thunderbolt/tb.h
> >>> @@ -1222,6 +1222,7 @@ struct usb4_port *usb4_port_device_add(struct tb_port *port);
> >>>  void usb4_port_device_remove(struct usb4_port *usb4);
> >>>  int usb4_port_device_resume(struct usb4_port *usb4);
> >>>  
> >>> +void tb_dp_resource_available_discovered(struct tb *tb, struct tb_port *port);
> >>
> >> Why not put this in the .h file next to the other tb_* calls?
> >>
> > 
> Hi Greg,
> 
> I forgot to explain that in this function, I have used a structure
> "struct tb_cm" which is defined and used only in tb.c file. Hence have
> to keep this function in tb.c file.

To be more specific, I mean why not put it below the line:
	int tb_dp_port_enable(struct tb_port *port, bool enable);
in this .h file in an attempt to keep things orderly.

thanks,

greg k-h