[cip-dev] [PATCH 4.19.y-cip 07/23] device connection: Find device connections also from device graphs

Marian-Cristian Rotariu
2020-02-18T14:05:04Z

From: Heikki Krogerus <heikki.krogerus@linux.intel.com>

commit 637e9e52b185e5b10372366bd6db97f27cf3f202 upstream.

If connections between devices are described in OF graph or
ACPI device graph, we can find them by using the
fwnode_graph_*() functions.

Acked-by: Hans de Goede <hdegoede@redhat.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Reviewed-by: Jun Li <jun.li@nxp.com>
Tested-by: Jun Li <jun.li@nxp.com>
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Marian-Cristian Rotariu <marian-cristian.rotariu.rb@bp.renesas.com>
---
drivers/base/devcon.c | 38 +++++++++++++++++++++++++++++++++++---
1 file changed, 35 insertions(+), 3 deletions(-)

diff --git a/drivers/base/devcon.c b/drivers/base/devcon.c
index 858b8d2..04db9ae 100644
--- a/drivers/base/devcon.c
+++ b/drivers/base/devcon.c
@@ -7,10 +7,37 @@
*/

#include <linux/device.h>
+#include <linux/property.h>

static DEFINE_MUTEX(devcon_lock);
static LIST_HEAD(devcon_list);

+typedef void *(*devcon_match_fn_t)(struct device_connection *con, int ep,
+ void *data);
+
+static void *
+fwnode_graph_devcon_match(struct fwnode_handle *fwnode, const char *con_id,
+ void *data, devcon_match_fn_t match)
+{
+ struct device_connection con = { .id = con_id };
+ struct fwnode_handle *ep;
+ void *ret;
+
+ fwnode_graph_for_each_endpoint(fwnode, ep) {
+ con.fwnode = fwnode_graph_get_remote_port_parent(ep);
+ if (!fwnode_device_is_available(con.fwnode))
+ continue;
+
+ ret = match(&con, -1, data);
+ fwnode_handle_put(con.fwnode);
+ if (ret) {
+ fwnode_handle_put(ep);
+ return ret;
+ }
+ }
+ return NULL;
+}
+
/**
* device_connection_find_match - Find physical connection to a device
* @dev: Device with the connection
@@ -23,10 +50,9 @@ static LIST_HEAD(devcon_list);
* caller is expecting to be returned.
*/
void *device_connection_find_match(struct device *dev, const char *con_id,
- void *data,
- void *(*match)(struct device_connection *con,
- int ep, void *data))
+ void *data, devcon_match_fn_t match)
{
+ struct fwnode_handle *fwnode = dev_fwnode(dev);
const char *devname = dev_name(dev);
struct device_connection *con;
void *ret = NULL;
@@ -35,6 +61,12 @@ void *device_connection_find_match(struct device *dev, const char *con_id,
if (!match)
return NULL;

+ if (fwnode) {
+ ret = fwnode_graph_devcon_match(fwnode, con_id, data, match);
+ if (ret)
+ return ret;
+ }
+
mutex_lock(&devcon_lock);

list_for_each_entry(con, &devcon_list, list) {
--
2.7.4