Re: [PATCH v5 1/7] device property: Add helper to match multiple connections

From: Rafael J. Wysocki
Date: Fri May 06 2022 - 14:21:32 EST


On Tue, Apr 26, 2022 at 12:15 PM Andy Shevchenko
<andy.shevchenko@xxxxxxxxx> wrote:
>
> On Sat, Apr 23, 2022 at 1:25 AM Bjorn Andersson
> <bjorn.andersson@xxxxxxxxxx> wrote:
> >
> > In some cases multiple connections with the same connection id
> > needs to be resolved from a fwnode graph.
> >
> > One such example is when separate hardware is used for performing muxing
> > and/or orientation switching of the SuperSpeed and SBU lines in a USB
> > Type-C connector. In this case the connector needs to belong to a graph
> > with multiple matching remote endpoints, and the Type-C controller needs
> > to be able to resolve them both.
> >
> > Add a new API that allows this kind of lookup.
>
> LGTM now,
> Reviewed-by: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
> thanks!

For this and the next patch in the series:

Acked-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>

and please feel free to route the whole lot via USB.

Thanks!

> > Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
> > ---
> >
> > Changes since v4:
> > - Added "Add" to patch subject
> > - Added "(Optional)" kernel-doc of fwnode_connection_find_matches()
> >
> > drivers/base/property.c | 109 +++++++++++++++++++++++++++++++++++++++
> > include/linux/property.h | 5 ++
> > 2 files changed, 114 insertions(+)
> >
> > diff --git a/drivers/base/property.c b/drivers/base/property.c
> > index 36401cfe432c..babab8cec7a0 100644
> > --- a/drivers/base/property.c
> > +++ b/drivers/base/property.c
> > @@ -1201,6 +1201,40 @@ fwnode_graph_devcon_match(struct fwnode_handle *fwnode, const char *con_id,
> > return NULL;
> > }
> >
> > +static unsigned int fwnode_graph_devcon_matches(struct fwnode_handle *fwnode,
> > + const char *con_id, void *data,
> > + devcon_match_fn_t match,
> > + void **matches,
> > + unsigned int matches_len)
> > +{
> > + struct fwnode_handle *node;
> > + struct fwnode_handle *ep;
> > + unsigned int count = 0;
> > + void *ret;
> > +
> > + fwnode_graph_for_each_endpoint(fwnode, ep) {
> > + if (matches && count >= matches_len) {
> > + fwnode_handle_put(ep);
> > + break;
> > + }
> > +
> > + node = fwnode_graph_get_remote_port_parent(ep);
> > + if (!fwnode_device_is_available(node)) {
> > + fwnode_handle_put(node);
> > + continue;
> > + }
> > +
> > + ret = match(node, con_id, data);
> > + fwnode_handle_put(node);
> > + if (ret) {
> > + if (matches)
> > + matches[count] = ret;
> > + count++;
> > + }
> > + }
> > + return count;
> > +}
> > +
> > static void *
> > fwnode_devcon_match(struct fwnode_handle *fwnode, const char *con_id,
> > void *data, devcon_match_fn_t match)
> > @@ -1223,6 +1257,37 @@ fwnode_devcon_match(struct fwnode_handle *fwnode, const char *con_id,
> > return NULL;
> > }
> >
> > +static unsigned int fwnode_devcon_matches(struct fwnode_handle *fwnode,
> > + const char *con_id, void *data,
> > + devcon_match_fn_t match,
> > + void **matches,
> > + unsigned int matches_len)
> > +{
> > + struct fwnode_handle *node;
> > + unsigned int count = 0;
> > + unsigned int i;
> > + void *ret;
> > +
> > + for (i = 0; ; i++) {
> > + if (matches && count >= matches_len)
> > + break;
> > +
> > + node = fwnode_find_reference(fwnode, con_id, i);
> > + if (IS_ERR(node))
> > + break;
> > +
> > + ret = match(node, NULL, data);
> > + fwnode_handle_put(node);
> > + if (ret) {
> > + if (matches)
> > + matches[count] = ret;
> > + count++;
> > + }
> > + }
> > +
> > + return count;
> > +}
> > +
> > /**
> > * fwnode_connection_find_match - Find connection from a device node
> > * @fwnode: Device node with the connection
> > @@ -1250,3 +1315,47 @@ void *fwnode_connection_find_match(struct fwnode_handle *fwnode,
> > return fwnode_devcon_match(fwnode, con_id, data, match);
> > }
> > EXPORT_SYMBOL_GPL(fwnode_connection_find_match);
> > +
> > +/**
> > + * fwnode_connection_find_matches - Find connections from a device node
> > + * @fwnode: Device node with the connection
> > + * @con_id: Identifier for the connection
> > + * @data: Data for the match function
> > + * @match: Function to check and convert the connection description
> > + * @matches: (Optional) array of pointers to fill with matches
> > + * @matches_len: Length of @matches
> > + *
> > + * Find up to @matches_len connections with unique identifier @con_id between
> > + * @fwnode and other device nodes. @match will be used to convert the
> > + * connection description to data the caller is expecting to be returned
> > + * through the @matches array.
> > + * If @matches is NULL @matches_len is ignored and the total number of resolved
> > + * matches is returned.
> > + *
> > + * Return: Number of matches resolved, or negative errno.
> > + */
> > +int fwnode_connection_find_matches(struct fwnode_handle *fwnode,
> > + const char *con_id, void *data,
> > + devcon_match_fn_t match,
> > + void **matches, unsigned int matches_len)
> > +{
> > + unsigned int count_graph;
> > + unsigned int count_ref;
> > +
> > + if (!fwnode || !match)
> > + return -EINVAL;
> > +
> > + count_graph = fwnode_graph_devcon_matches(fwnode, con_id, data, match,
> > + matches, matches_len);
> > +
> > + if (matches) {
> > + matches += count_graph;
> > + matches_len -= count_graph;
> > + }
> > +
> > + count_ref = fwnode_devcon_matches(fwnode, con_id, data, match,
> > + matches, matches_len);
> > +
> > + return count_graph + count_ref;
> > +}
> > +EXPORT_SYMBOL_GPL(fwnode_connection_find_matches);
> > diff --git a/include/linux/property.h b/include/linux/property.h
> > index fc24d45632eb..a5b429d623f6 100644
> > --- a/include/linux/property.h
> > +++ b/include/linux/property.h
> > @@ -451,6 +451,11 @@ static inline void *device_connection_find_match(struct device *dev,
> > return fwnode_connection_find_match(dev_fwnode(dev), con_id, data, match);
> > }
> >
> > +int fwnode_connection_find_matches(struct fwnode_handle *fwnode,
> > + const char *con_id, void *data,
> > + devcon_match_fn_t match,
> > + void **matches, unsigned int matches_len);
> > +
> > /* -------------------------------------------------------------------------- */
> > /* Software fwnode support - when HW description is incomplete or missing */
> >
> > --
> > 2.35.1
> >
>
>
> --
> With Best Regards,
> Andy Shevchenko