On Wed, Mar 19, 2025 at 12:58:38AM +0100, Christian Marangi wrote: > Implement the foundation of OF support for PCS driver. > > To support this, implement a simple Provider API where a PCS driver can > expose multiple PCS with an xlate .get function. > > PCS driver will have to call of_pcs_add_provider() and pass the device > node pointer and a xlate function to return the correct PCS for the > requested interface and the passed #pcs-cells. > > This will register the PCS in a global list of providers so that > consumer can access it. > > Consumer will then use of_pcs_get() to get the actual PCS by passing the > device_node pointer, the index for #pcs-cells and the requested > interface. > > For simple implementation where #pcs-cells is 0 and the PCS driver > expose a single PCS, the xlate function of_pcs_simple_get() is > provided. In such case the passed interface is ignored and is expected > that the PCS supports any interface mode supported by the MAC. > > For advanced implementation a custom xlate function is required. Such > function should return an error if the PCS is not supported for the > requested interface type. > > This is needed for the correct function of of_phylink_mac_select_pcs() > later described. > > PCS driver on removal should first call phylink_pcs_release() on every > PCS the driver provides and then correctly delete as a provider with > the usage of of_pcs_del_provider(). > > A generic function for .mac_select_pcs is provided for any MAC driver > that will declare PCS in DT, of_phylink_mac_select_pcs(). > This function will parse "pcs-handle" property and will try every PCS > declared in DT until one that supports the requested interface type is > found. This works by leveraging the return value of the xlate function > returned by of_pcs_get() and checking if it's an ERROR or NULL, in such > case the next PCS in the phandle array is tested. > > Some additional helper are provided for xlate functions, > pcs_supports_interface() as a simple function to check if the requested > interface is supported by the PCS and phylink_pcs_release() to release a > PCS from a phylink instance. > > Co-developed-by: Daniel Golle <daniel@xxxxxxxxxxxxxx> > Signed-off-by: Daniel Golle <daniel@xxxxxxxxxxxxxx> > Signed-off-by: Christian Marangi <ansuelsmth@xxxxxxxxx> As a general comment, should we be developing stuff that is DT-centric or fwnode-centric. We already have users of phylink using swnodes, and it seems bad to design something today that is centred around just one method of describing something. -- RMK's Patch system: https://www.armlinux.org.uk/developer/patches/ FTTP is here! 80Mbps down 10Mbps up. Decent connectivity at last!
