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-rw-r--r--drivers/usb/phy/phy-am335x-control.c9
-rw-r--r--drivers/usb/phy/phy.c3
2 files changed, 12 insertions, 0 deletions
diff --git a/drivers/usb/phy/phy-am335x-control.c b/drivers/usb/phy/phy-am335x-control.c
index d75196ad5f2f..35b6083b7999 100644
--- a/drivers/usb/phy/phy-am335x-control.c
+++ b/drivers/usb/phy/phy-am335x-control.c
@@ -3,6 +3,7 @@
#include <linux/err.h>
#include <linux/of.h>
#include <linux/io.h>
+#include <linux/delay.h>
#include "am35x-phy-control.h"
struct am335x_control_usb {
@@ -86,6 +87,14 @@ static void am335x_phy_power(struct phy_control *phy_ctrl, u32 id, bool on)
}
writel(val, usb_ctrl->phy_reg + reg);
+
+ /*
+ * Give the PHY ~1ms to complete the power up operation.
+ * Tests have shown unstable behaviour if other USB PHY related
+ * registers are written too shortly after such a transition.
+ */
+ if (on)
+ mdelay(1);
}
static const struct phy_control ctrl_am335x = {
diff --git a/drivers/usb/phy/phy.c b/drivers/usb/phy/phy.c
index 8afa813d690b..36b6bce33b20 100644
--- a/drivers/usb/phy/phy.c
+++ b/drivers/usb/phy/phy.c
@@ -132,6 +132,9 @@ struct usb_phy *usb_get_phy(enum usb_phy_type type)
if (IS_ERR(phy) || !try_module_get(phy->dev->driver->owner)) {
pr_debug("PHY: unable to find transceiver of type %s\n",
usb_phy_type_string(type));
+ if (!IS_ERR(phy))
+ phy = ERR_PTR(-ENODEV);
+
goto err0;
}