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authorRussell King <rmk+kernel@armlinux.org.uk>2019-11-08 17:39:29 +0000
committerDavid S. Miller <davem@davemloft.net>2019-11-09 19:35:53 -0800
commit727b3668b730634228fc65c336c2a7a080e02885 (patch)
tree061758f9f98b33a681b4d564a2035fd1d361e7e4 /drivers/net
parent14684b93019a2d2ece0df5acaf921924541b928d (diff)
net: sfp: rework upstream interface
The current upstream interface is an all-or-nothing, which is sub-optimal for future changes, as it doesn't allow the upstream driver to prepare for the SFP module becoming available, as it is at boot. Switch to a find-sfp-bus, add-upstream, del-upstream, put-sfp-bus interface structure instead, which allows the upstream driver to prepare for a module being available as soon as add-upstream is called. Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net')
-rw-r--r--drivers/net/phy/phylink.c10
-rw-r--r--drivers/net/phy/sfp-bus.c92
2 files changed, 71 insertions, 31 deletions
diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index f16d9e92a81a..e3fbc8e93317 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -567,7 +567,7 @@ static int phylink_register_sfp(struct phylink *pl,
struct sfp_bus *bus;
int ret;
- bus = sfp_register_upstream_node(fwnode, pl, &sfp_phylink_ops);
+ bus = sfp_bus_find_fwnode(fwnode);
if (IS_ERR(bus)) {
ret = PTR_ERR(bus);
phylink_err(pl, "unable to attach SFP bus: %d\n", ret);
@@ -576,7 +576,10 @@ static int phylink_register_sfp(struct phylink *pl,
pl->sfp_bus = bus;
- return 0;
+ ret = sfp_bus_add_upstream(bus, pl, &sfp_phylink_ops);
+ sfp_bus_put(bus);
+
+ return ret;
}
/**
@@ -670,8 +673,7 @@ EXPORT_SYMBOL_GPL(phylink_create);
*/
void phylink_destroy(struct phylink *pl)
{
- if (pl->sfp_bus)
- sfp_unregister_upstream(pl->sfp_bus);
+ sfp_bus_del_upstream(pl->sfp_bus);
if (pl->link_gpio)
gpiod_put(pl->link_gpio);
diff --git a/drivers/net/phy/sfp-bus.c b/drivers/net/phy/sfp-bus.c
index d037aab6a71d..715d45214e18 100644
--- a/drivers/net/phy/sfp-bus.c
+++ b/drivers/net/phy/sfp-bus.c
@@ -329,10 +329,19 @@ static void sfp_bus_release(struct kref *kref)
kfree(bus);
}
-static void sfp_bus_put(struct sfp_bus *bus)
+/**
+ * sfp_bus_put() - put a reference on the &struct sfp_bus
+ * bus: the &struct sfp_bus found via sfp_bus_find_fwnode()
+ *
+ * Put a reference on the &struct sfp_bus and free the underlying structure
+ * if this was the last reference.
+ */
+void sfp_bus_put(struct sfp_bus *bus)
{
- kref_put_mutex(&bus->kref, sfp_bus_release, &sfp_mutex);
+ if (bus)
+ kref_put_mutex(&bus->kref, sfp_bus_release, &sfp_mutex);
}
+EXPORT_SYMBOL_GPL(sfp_bus_put);
static int sfp_register_bus(struct sfp_bus *bus)
{
@@ -348,11 +357,11 @@ static int sfp_register_bus(struct sfp_bus *bus)
return ret;
}
}
+ bus->registered = true;
bus->socket_ops->attach(bus->sfp);
if (bus->started)
bus->socket_ops->start(bus->sfp);
bus->upstream_ops->attach(bus->upstream, bus);
- bus->registered = true;
return 0;
}
@@ -446,13 +455,12 @@ static void sfp_upstream_clear(struct sfp_bus *bus)
}
/**
- * sfp_register_upstream_node() - parse and register the neighbouring device
+ * sfp_bus_find_fwnode() - parse and locate the SFP bus from fwnode
* @fwnode: firmware node for the parent device (MAC or PHY)
- * @upstream: the upstream private data
- * @ops: the upstream's &struct sfp_upstream_ops
*
- * Parse the parent device's firmware node for a SFP bus, and register the
- * SFP bus using sfp_register_upstream().
+ * Parse the parent device's firmware node for a SFP bus, and locate
+ * the sfp_bus structure, incrementing its reference count. This must
+ * be put via sfp_bus_put() when done.
*
* Returns: on success, a pointer to the sfp_bus structure,
* %NULL if no SFP is specified,
@@ -462,9 +470,7 @@ static void sfp_upstream_clear(struct sfp_bus *bus)
* %-ENOMEM if we failed to allocate the bus.
* an error from the upstream's connect_phy() method.
*/
-struct sfp_bus *sfp_register_upstream_node(struct fwnode_handle *fwnode,
- void *upstream,
- const struct sfp_upstream_ops *ops)
+struct sfp_bus *sfp_bus_find_fwnode(struct fwnode_handle *fwnode)
{
struct fwnode_reference_args ref;
struct sfp_bus *bus;
@@ -482,7 +488,39 @@ struct sfp_bus *sfp_register_upstream_node(struct fwnode_handle *fwnode,
if (!bus)
return ERR_PTR(-ENOMEM);
+ return bus;
+}
+EXPORT_SYMBOL_GPL(sfp_bus_find_fwnode);
+
+/**
+ * sfp_bus_add_upstream() - parse and register the neighbouring device
+ * @bus: the &struct sfp_bus found via sfp_bus_find_fwnode()
+ * @upstream: the upstream private data
+ * @ops: the upstream's &struct sfp_upstream_ops
+ *
+ * Add upstream driver for the SFP bus, and if the bus is complete, register
+ * the SFP bus using sfp_register_upstream(). This takes a reference on the
+ * bus, so it is safe to put the bus after this call.
+ *
+ * Returns: on success, a pointer to the sfp_bus structure,
+ * %NULL if no SFP is specified,
+ * on failure, an error pointer value:
+ * corresponding to the errors detailed for
+ * fwnode_property_get_reference_args().
+ * %-ENOMEM if we failed to allocate the bus.
+ * an error from the upstream's connect_phy() method.
+ */
+int sfp_bus_add_upstream(struct sfp_bus *bus, void *upstream,
+ const struct sfp_upstream_ops *ops)
+{
+ int ret;
+
+ /* If no bus, return success */
+ if (!bus)
+ return 0;
+
rtnl_lock();
+ kref_get(&bus->kref);
bus->upstream_ops = ops;
bus->upstream = upstream;
@@ -495,33 +533,33 @@ struct sfp_bus *sfp_register_upstream_node(struct fwnode_handle *fwnode,
}
rtnl_unlock();
- if (ret) {
+ if (ret)
sfp_bus_put(bus);
- bus = ERR_PTR(ret);
- }
- return bus;
+ return ret;
}
-EXPORT_SYMBOL_GPL(sfp_register_upstream_node);
+EXPORT_SYMBOL_GPL(sfp_bus_add_upstream);
/**
- * sfp_unregister_upstream() - Unregister sfp bus
+ * sfp_bus_del_upstream() - Delete a sfp bus
* @bus: a pointer to the &struct sfp_bus structure for the sfp module
*
- * Unregister a previously registered upstream connection for the SFP
- * module. @bus is returned from sfp_register_upstream().
+ * Delete a previously registered upstream connection for the SFP
+ * module. @bus should have been added by sfp_bus_add_upstream().
*/
-void sfp_unregister_upstream(struct sfp_bus *bus)
+void sfp_bus_del_upstream(struct sfp_bus *bus)
{
- rtnl_lock();
- if (bus->sfp)
- sfp_unregister_bus(bus);
- sfp_upstream_clear(bus);
- rtnl_unlock();
+ if (bus) {
+ rtnl_lock();
+ if (bus->sfp)
+ sfp_unregister_bus(bus);
+ sfp_upstream_clear(bus);
+ rtnl_unlock();
- sfp_bus_put(bus);
+ sfp_bus_put(bus);
+ }
}
-EXPORT_SYMBOL_GPL(sfp_unregister_upstream);
+EXPORT_SYMBOL_GPL(sfp_bus_del_upstream);
/* Socket driver entry points */
int sfp_add_phy(struct sfp_bus *bus, struct phy_device *phydev)