Some USB phy drivers have different handling for the controller in each
dr_mode. But the phy driver does not have visibility to the dr_mode of
the controller.
This adds an api to return the dr_mode of the controller which
associates the given phy node.
Signed-off-by: Bin Liu <b-liu@xxxxxx>
---
v5: - to simplify the code, add usb_get_dr_mode_from_string() to query
dr_mode from string
v4: - iterating all phy nodes in the associated controller
- add of_node_put() to decrement refcount
v3: search controller node from dt root, as the phy and controller nodes
might not have the same parent.
v2: move drivers/usb/phy/phy-am335x.c changes into patch 3/3.
drivers/usb/common/common.c | 60 ++++++++++++++++++++++++++++++++++++++++-----
include/linux/usb/of.h | 5 ++++
2 files changed, 59 insertions(+), 6 deletions(-)
diff --git a/drivers/usb/common/common.c b/drivers/usb/common/common.c
index 673d530..a11bb15 100644
--- a/drivers/usb/common/common.c
+++ b/drivers/usb/common/common.c
@@ -17,6 +17,7 @@
#include <linux/usb/ch9.h>
#include <linux/usb/of.h>
#include <linux/usb/otg.h>
+#include <linux/of_platform.h>
const char *usb_otg_state_string(enum usb_otg_state state)
{
@@ -106,23 +107,70 @@ static const char *const usb_dr_modes[] = {
[USB_DR_MODE_OTG] = "otg",
};
+static enum usb_dr_mode usb_get_dr_mode_from_string(const char *str)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(usb_dr_modes); i++)
+ if (!strcmp(usb_dr_modes[i], str))
+ return i;
+
+ return USB_DR_MODE_UNKNOWN;
+}
+
enum usb_dr_mode usb_get_dr_mode(struct device *dev)
{
const char *dr_mode;
- int err, i;
+ int err;
err = device_property_read_string(dev, "dr_mode", &dr_mode);
if (err < 0)
return USB_DR_MODE_UNKNOWN;
- for (i = 0; i < ARRAY_SIZE(usb_dr_modes); i++)
- if (!strcmp(dr_mode, usb_dr_modes[i]))
- return i;
-
- return USB_DR_MODE_UNKNOWN;
+ return usb_get_dr_mode_from_string(dr_mode);
}
EXPORT_SYMBOL_GPL(usb_get_dr_mode);
+/**
+ * of_usb_get_dr_mode_by_phy - Get dual role mode for the controller device
+ * which is associated with the given phy device_node
+ * @np: Pointer to the given phy device_node
+ *
+ * In dts a usb controller associates with phy devices. The function gets
+ * the string from property 'dr_mode' of the controller associated with the
+ * given phy device node, and returns the correspondig enum usb_dr_mode.
+ */
+enum usb_dr_mode of_usb_get_dr_mode_by_phy(struct device_node *phy_np)
+{
+ struct device_node *controller = NULL;
+ struct device_node *phy;
+ const char *dr_mode;
+ int index;
+ int err;
+
+ do {
+ controller = of_find_node_with_property(controller, "phys");
+ index = 0;
+ do {
+ phy = of_parse_phandle(controller, "phys", index);
+ of_node_put(phy);
+ if (phy == phy_np)
+ goto finish;
+ index++;
+ } while (phy);
+ } while (controller);
+
+finish:
+ err = of_property_read_string(controller, "dr_mode", &dr_mode);
+ of_node_put(controller);
+
+ if (err < 0)
+ return USB_DR_MODE_UNKNOWN;
+
+ return usb_get_dr_mode_from_string(dr_mode);
+}
+EXPORT_SYMBOL_GPL(of_usb_get_dr_mode_by_phy);
+
#ifdef CONFIG_OF
/**
* of_usb_host_tpl_support - to get if Targeted Peripheral List is supported
diff --git a/include/linux/usb/of.h b/include/linux/usb/of.h
index c3fe9e4..3805757 100644
--- a/include/linux/usb/of.h
+++ b/include/linux/usb/of.h
@@ -12,10 +12,15 @@
#include <linux/usb/phy.h>
#if IS_ENABLED(CONFIG_OF)
+enum usb_dr_mode of_usb_get_dr_mode_by_phy(struct device_node *phy_np);
bool of_usb_host_tpl_support(struct device_node *np);
int of_usb_update_otg_caps(struct device_node *np,
struct usb_otg_caps *otg_caps);
#else
+enum usb_dr_mode of_usb_get_dr_mode_by_phy(struct device_node *phy_np)
+{
+ return USB_DR_MODE_UNKNOWN;
+}
static inline bool of_usb_host_tpl_support(struct device_node *np)
{
return false;
--
1.8.4
--
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