On Wed, May 17, 2023 at 1:54 PM Sakari Ailus
<sakari.ailus@xxxxxxxxxxxxxxx> wrote:
>
> Hi Rafael,
>
> Thanks for the review.
>
> On Wed, May 17, 2023 at 12:53:43PM +0200, Rafael J. Wysocki wrote:
> > > + list_for_each_entry(csi2, &ctx->crs_csi2_head, list) {
> > > + struct acpi_device_software_nodes *local_swnodes;
> > > + struct crs_csi2_instance *inst;
> > > +
> > > + local_swnodes = crs_csi2_swnode_get(csi2->handle);
> > > + if (WARN_ON_ONCE(!local_swnodes))
> > > + continue;
> > > +
> > > + list_for_each_entry(inst, &csi2->buses, list) {
> > > + struct acpi_device_software_nodes *remote_swnodes;
> > > + struct acpi_device_software_node_port *local_port;
> > > + struct acpi_device_software_node_port *remote_port;
> > > + struct software_node *local_node, *remote_node;
> > > + unsigned int local_index, remote_index;
> > > + unsigned int bus_type;
> > > +
> > > + remote_swnodes = crs_csi2_swnode_get(inst->remote_handle);
> > > + if (WARN_ON_ONCE(!remote_swnodes))
> > > + continue;
> > > +
> > > + local_index = next_csi2_port_index(local_swnodes, inst->csi2.local_port_instance);
> > > + remote_index = next_csi2_port_index(remote_swnodes, inst->csi2.resource_source.index);
> > > +
> > > + if (WARN_ON_ONCE(local_index >= local_swnodes->num_ports) ||
> > > + WARN_ON_ONCE(remote_index >= remote_swnodes->num_ports))
> > > + goto out_free;
> > > +
> > > + switch (inst->csi2.phy_type) {
> > > + case ACPI_CRS_CSI2_PHY_TYPE_C:
> > > + bus_type = V4L2_FWNODE_BUS_TYPE_CSI2_CPHY;
> > > + break;
> > > + case ACPI_CRS_CSI2_PHY_TYPE_D:
> > > + bus_type = V4L2_FWNODE_BUS_TYPE_CSI2_DPHY;
> > > + break;
> > > + default:
> > > + acpi_handle_info(csi2->handle,
> > > + "ignoring CSI-2 PHY type %u\n",
> > > + inst->csi2.phy_type);
> > > + continue;
> > > + }
> > > +
> > > + local_port = &local_swnodes->ports[local_index];
> > > + local_node = &local_swnodes->nodes[ACPI_DEVICE_SWNODE_EP(local_index)];
> > > + local_port->remote_ep_ref[0] = SOFTWARE_NODE_REFERENCE(local_node);
> >
> > This looks odd. Is local_port pointing to its own node as a remote
> > endpont, or am I confused?
>
> This is a reference to a software node that will be, in turn, referenced by
> the "remote-endpoint" property entry in the remote node. Look for
> ACPI_DEVICE_SWNODE_EP_REMOTE_EP a few lines below these.
To be precise, IIUC, it is going to be the "remote-endpoint" value for
the remote node.
OK, thanks for the explanation. This isn't exactly straightforward TBH.
