[PATCH 1/2] usb: phy: Add interface to get phy give of device_node.

NeilBrown
2015-03-22T22:53:16Z

From: NeilBrown <neilb@suse.de>

Split the "get phy from device_node" functionality out of
"get phy by phandle" so it can be used directly.

This is useful when a battery-charger is intimately associated with a
particular phy but handled by a separate driver. The charger
can find the device_node based on sibling relationships
without the need for a redundant declaration in the devicetree
description.

As a peripheral that gets a phy will often want to register a
notifier block, and de-register it later, that functionality
is included so the de-registration is automatic.

Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: NeilBrown <neilb@suse.de>
---
drivers/usb/phy/phy.c | 97 ++++++++++++++++++++++++++++++++++-------------
include/linux/usb/phy.h | 2 +
2 files changed, 72 insertions(+), 27 deletions(-)

diff --git a/drivers/usb/phy/phy.c b/drivers/usb/phy/phy.c
index 2f9735b35338..6b089e19e8db 100644
--- a/drivers/usb/phy/phy.c
+++ b/drivers/usb/phy/phy.c
@@ -22,6 +22,11 @@ static LIST_HEAD(phy_list);
static LIST_HEAD(phy_bind_list);
static DEFINE_SPINLOCK(phy_lock);

+struct phy_devm {
+ struct usb_phy *phy;
+ struct notifier_block *nb;
+};
+
static struct usb_phy *__usb_find_phy(struct list_head *list,
enum usb_phy_type type)
{
@@ -79,6 +84,15 @@ static void devm_usb_phy_release(struct device *dev, void *res)
usb_put_phy(phy);
}

+static void devm_usb_phy_release2(struct device *dev, void *_res)
+{
+ struct phy_devm *res = _res;
+
+ if (res->nb)
+ usb_unregister_notifier(res->phy, res->nb);
+ usb_put_phy(res->phy);
+}
+
static int devm_usb_phy_match(struct device *dev, void *res, void *match_data)
{
return res == match_data;
@@ -151,40 +165,30 @@ err0:
EXPORT_SYMBOL_GPL(usb_get_phy);

/**
- * devm_usb_get_phy_by_phandle - find the USB PHY by phandle
+ * devm_usb_get_phy_by_node - find the USB PHY by device_node
* @dev - device that requests this phy
- * @phandle - name of the property holding the phy phandle value
- * @index - the index of the phy
+ * @node - the device_node for the phy device.
+ * @nb - a notifier_block to register with the phy.
*
- * Returns the phy driver associated with the given phandle value,
+ * Returns the phy driver associated with the given device_node,
* after getting a refcount to it, -ENODEV if there is no such phy or
- * -EPROBE_DEFER if there is a phandle to the phy, but the device is
- * not yet loaded. While at that, it also associates the device with
+ * -EPROBE_DEFER if the device is not yet loaded. While at that, it
+ * also associates the device with
* the phy using devres. On driver detach, release function is invoked
* on the devres data, then, devres data is freed.
*
- * For use by USB host and peripheral drivers.
+ * For use by peripheral drivers for devices related to a phy,
+ * such as a charger.
*/
-struct usb_phy *devm_usb_get_phy_by_phandle(struct device *dev,
- const char *phandle, u8 index)
+struct usb_phy *devm_usb_get_phy_by_node(struct device *dev,
+ struct device_node *node,
+ struct notifier_block *nb)
{
- struct usb_phy *phy = ERR_PTR(-ENOMEM), **ptr;
+ struct usb_phy *phy = ERR_PTR(-ENOMEM);
+ struct phy_devm *ptr;
unsigned long flags;
- struct device_node *node;

- if (!dev->of_node) {
- dev_dbg(dev, "device does not have a device node entry\n");
- return ERR_PTR(-EINVAL);
- }
-
- node = of_parse_phandle(dev->of_node, phandle, index);
- if (!node) {
- dev_dbg(dev, "failed to get %s phandle in %s node\n", phandle,
- dev->of_node->full_name);
- return ERR_PTR(-ENODEV);
- }
-
- ptr = devres_alloc(devm_usb_phy_release, sizeof(*ptr), GFP_KERNEL);
+ ptr = devres_alloc(devm_usb_phy_release2, sizeof(*ptr), GFP_KERNEL);
if (!ptr) {
dev_dbg(dev, "failed to allocate memory for devres\n");
goto err0;
@@ -203,8 +207,10 @@ struct usb_phy *devm_usb_get_phy_by_phandle(struct device *dev,
devres_free(ptr);
goto err1;
}
-
- *ptr = phy;
+ if (nb)
+ usb_register_notifier(phy, nb);
+ ptr->phy = phy;
+ ptr->nb = nb;
devres_add(dev, ptr);

get_device(phy->dev);
@@ -213,10 +219,47 @@ err1:
spin_unlock_irqrestore(&phy_lock, flags);

err0:
- of_node_put(node);

return phy;
}
+EXPORT_SYMBOL_GPL(devm_usb_get_phy_by_node);
+
+/**
+ * devm_usb_get_phy_by_phandle - find the USB PHY by phandle
+ * @dev - device that requests this phy
+ * @phandle - name of the property holding the phy phandle value
+ * @index - the index of the phy
+ *
+ * Returns the phy driver associated with the given phandle value,
+ * after getting a refcount to it, -ENODEV if there is no such phy or
+ * -EPROBE_DEFER if there is a phandle to the phy, but the device is
+ * not yet loaded. While at that, it also associates the device with
+ * the phy using devres. On driver detach, release function is invoked
+ * on the devres data, then, devres data is freed.
+ *
+ * For use by USB host and peripheral drivers.
+ */
+struct usb_phy *devm_usb_get_phy_by_phandle(struct device *dev,
+ const char *phandle, u8 index)
+{
+ struct device_node *node;
+ struct usb_phy *phy;
+
+ if (!dev->of_node) {
+ dev_dbg(dev, "device does not have a device node entry\n");
+ return ERR_PTR(-EINVAL);
+ }
+
+ node = of_parse_phandle(dev->of_node, phandle, index);
+ if (!node) {
+ dev_dbg(dev, "failed to get %s phandle in %s node\n", phandle,
+ dev->of_node->full_name);
+ return ERR_PTR(-ENODEV);
+ }
+ phy = devm_usb_get_phy_by_node(dev, node, NULL);
+ of_node_put(node);
+ return phy;
+}
EXPORT_SYMBOL_GPL(devm_usb_get_phy_by_phandle);

/**
diff --git a/include/linux/usb/phy.h b/include/linux/usb/phy.h
index bc91b5d380fd..8ed1e29ef329 100644
--- a/include/linux/usb/phy.h
+++ b/include/linux/usb/phy.h
@@ -205,6 +205,8 @@ extern struct usb_phy *usb_get_phy_dev(struct device *dev, u8 index);
extern struct usb_phy *devm_usb_get_phy_dev(struct device *dev, u8 index);
extern struct usb_phy *devm_usb_get_phy_by_phandle(struct device *dev,
const char *phandle, u8 index);
+extern struct usb_phy *devm_usb_get_phy_by_node(struct device *dev,
+ struct device_node *node, struct notifier_block *nb);
extern void usb_put_phy(struct usb_phy *);
extern void devm_usb_put_phy(struct device *dev, struct usb_phy *x);
extern int usb_bind_phy(const char *dev_name, u8 index,