From: Kishon Vijay Abraham I <kishon@xxxxxx>
This patch adds an API to get usb phy by passing a device node phandle value.
The new added devm_usb_get_phy_by_phandle() function will return a pointer to
the phy on success, -EPROBE_DEFER if there is a device_node for the phandle,
but the phy has not been added, or a ERR_PTR() otherwise.
Since it's possible to obtain a phy by phandle, the checks in usb_add_phy() for
a valid phy type is removed (now it's just a debug message if a user tries to
add a phy with undefined type). This also allows to add multiple phys of same
type.
Cc: Richard Zhao <richard.zhao@xxxxxxxxxxxxx>
Cc: Marek Vasut <marex@xxxxxxx>
Signed-off-by: Kishon Vijay Abraham I <kishon@xxxxxx>
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
---
drivers/usb/otg/otg.c | 96 ++++++++++++++++++++++++++++++++++++++++-------
include/linux/usb/otg.h | 8 ++++
2 files changed, 90 insertions(+), 14 deletions(-)
diff --git a/drivers/usb/otg/otg.c b/drivers/usb/otg/otg.c
index 98c430e..23618de 100644
--- a/drivers/usb/otg/otg.c
+++ b/drivers/usb/otg/otg.c
@@ -15,6 +15,7 @@
#include <linux/device.h>
#include <linux/module.h>
#include <linux/slab.h>
+#include <linux/of.h>
#include <linux/usb/otg.h>
@@ -36,6 +37,21 @@ static struct usb_phy *__usb_find_phy(struct list_head *list,
return ERR_PTR(-ENODEV);
}
+static struct usb_phy *__of_usb_find_phy(struct list_head *list,
+ struct device_node *node)
+{
+ struct usb_phy *phy;
+
+ list_for_each_entry(phy, list, head) {
+ if (node != phy->dev->of_node)
+ continue;
+
+ return phy;
+ }
+
+ return ERR_PTR(-ENODEV);
+}
+
static void devm_usb_phy_release(struct device *dev, void *res)
{
struct usb_phy *phy = *(struct usb_phy **)res;
@@ -112,6 +128,66 @@ err0:
EXPORT_SYMBOL(usb_get_phy);
/**
+ * 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
+ *
+ * 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)
+{
+ struct usb_phy *phy = NULL, **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, 0);
+ 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);
+ if (!ptr) {
+ dev_dbg(dev, "failed to allocate memory for devres\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ spin_lock_irqsave(&phy_lock, flags);
+
+ phy = __of_usb_find_phy(&phy_list, node);
+ if (IS_ERR(phy) || !try_module_get(phy->dev->driver->owner)) {
+ phy = ERR_PTR(-EPROBE_DEFER);
+ devres_free(ptr);
+ goto err0;
+ }
+
+ *ptr = phy;
+ devres_add(dev, ptr);
+
+ get_device(phy->dev);
+
+err0:
+ spin_unlock_irqrestore(&phy_lock, flags);
+
+ return phy;
+}
+EXPORT_SYMBOL(devm_usb_get_phy_by_phandle);
+
+/**
* devm_usb_put_phy - release the USB PHY
* @dev - device that wants to release this phy
* @phy - the phy returned by devm_usb_get_phy()
@@ -158,32 +234,24 @@ EXPORT_SYMBOL(usb_put_phy);
*/
int usb_add_phy(struct usb_phy *x, enum usb_phy_type type)
{
- int ret = 0;
unsigned long flags;
struct usb_phy *phy;
- if (x && x->type != USB_PHY_TYPE_UNDEFINED) {
- dev_err(x->dev, "not accepting initialized PHY %s\n", x->label);
- return -EINVAL;
- }
+ if (x && x->type != USB_PHY_TYPE_UNDEFINED)
+ dev_dbg(x->dev, "add a phy with undefined type %s\n", x->label);
spin_lock_irqsave(&phy_lock, flags);
- list_for_each_entry(phy, &phy_list, head) {
- if (phy->type == type) {
- ret = -EBUSY;
- dev_err(x->dev, "transceiver type %s already exists\n",
+ list_for_each_entry(phy, &phy_list, head)
+ if (phy->type == type)
+ dev_dbg(x->dev, "transceiver type %s already exists\n",
usb_phy_type_string(type));
- goto out;
- }
- }
x->type = type;
list_add_tail(&x->head, &phy_list);
-out:
spin_unlock_irqrestore(&phy_lock, flags);
- return ret;
+ return 0;
}
EXPORT_SYMBOL(usb_add_phy);
diff --git a/include/linux/usb/otg.h b/include/linux/usb/otg.h
index 45824be..602d6b4 100644
--- a/include/linux/usb/otg.h
+++ b/include/linux/usb/otg.h
@@ -190,6 +190,8 @@ usb_phy_shutdown(struct usb_phy *x)
extern struct usb_phy *usb_get_phy(enum usb_phy_type type);
extern struct usb_phy *devm_usb_get_phy(struct device *dev,
enum usb_phy_type type);
+extern struct usb_phy *devm_usb_get_phy_by_phandle(struct device *dev,
+ const char *phandle);
extern void usb_put_phy(struct usb_phy *);
extern void devm_usb_put_phy(struct device *dev, struct usb_phy *x);
extern const char *otg_state_string(enum usb_otg_state state);
@@ -205,6 +207,12 @@ static inline struct usb_phy *devm_usb_get_phy(struct device *dev,
return NULL;
}
+static inline struct usb_phy *devm_usb_get_phy_by_phandle(struct device *dev,
+ const char *phandle)
+{
+ return NULL;
+}
+
static inline void usb_put_phy(struct usb_phy *x)
{
}
--
1.7.10.4
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