usb: otg: add device tree support to otg library
Added an API devm_usb_get_phy_by_phandle(), to get usb phy by passing a
device node phandle value. This 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.
Cc: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/otg/otg.c b/drivers/usb/otg/otg.c
index 4bb4333..e181439 100644
--- a/drivers/usb/otg/otg.c
+++ b/drivers/usb/otg/otg.c
@@ -13,7 +13,9 @@
#include <linux/export.h>
#include <linux/err.h>
#include <linux/device.h>
+#include <linux/module.h>
#include <linux/slab.h>
+#include <linux/of.h>
#include <linux/usb/otg.h>
@@ -54,6 +56,20 @@
return ERR_PTR(-ENODEV);
}
+static struct usb_phy *__of_usb_find_phy(struct device_node *node)
+{
+ struct usb_phy *phy;
+
+ list_for_each_entry(phy, &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;
@@ -129,6 +145,70 @@
}
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
+ * @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 usb_phy *phy = ERR_PTR(-ENOMEM), **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);
+ if (!ptr) {
+ dev_dbg(dev, "failed to allocate memory for devres\n");
+ goto err0;
+ }
+
+ spin_lock_irqsave(&phy_lock, flags);
+
+ phy = __of_usb_find_phy(node);
+ if (IS_ERR(phy) || !try_module_get(phy->dev->driver->owner)) {
+ phy = ERR_PTR(-EPROBE_DEFER);
+ devres_free(ptr);
+ goto err1;
+ }
+
+ *ptr = phy;
+ devres_add(dev, ptr);
+
+ get_device(phy->dev);
+
+err1:
+ spin_unlock_irqrestore(&phy_lock, flags);
+
+err0:
+ of_node_put(node);
+
+ return phy;
+}
+EXPORT_SYMBOL(devm_usb_get_phy_by_phandle);
+
/**
* usb_get_phy_dev - find the USB PHY
* @dev - device that requests this phy