It is a hardware bug in RK3288, the only way to solve it is to
reset the phy.

Signed-off-by: Randy Li <ay...@soulik.info>
---
 .../devicetree/bindings/phy/rockchip-usb-phy.txt     |  3 +++
 drivers/phy/phy-rockchip-usb.c                       | 20 ++++++++++++++++++++
 2 files changed, 23 insertions(+)

diff --git a/Documentation/devicetree/bindings/phy/rockchip-usb-phy.txt 
b/Documentation/devicetree/bindings/phy/rockchip-usb-phy.txt
index cc6be96..57dc388 100644
--- a/Documentation/devicetree/bindings/phy/rockchip-usb-phy.txt
+++ b/Documentation/devicetree/bindings/phy/rockchip-usb-phy.txt
@@ -27,6 +27,9 @@ Optional Properties:
 - clocks : phandle + clock specifier for the phy clocks
 - clock-names: string, clock name, must be "phyclk"
 - #clock-cells: for users of the phy-pll, should be 0
+- reset-names: Only allow the following entries:
+ - phy-reset
+- resets: Must contain an entry for each entry in reset-names.
 
 Example:
 
diff --git a/drivers/phy/phy-rockchip-usb.c b/drivers/phy/phy-rockchip-usb.c
index 2a7381f..734987f 100644
--- a/drivers/phy/phy-rockchip-usb.c
+++ b/drivers/phy/phy-rockchip-usb.c
@@ -29,6 +29,7 @@
 #include <linux/reset.h>
 #include <linux/regmap.h>
 #include <linux/mfd/syscon.h>
+#include <linux/delay.h>
 
 static int enable_usb_uart;
 
@@ -64,6 +65,7 @@ struct rockchip_usb_phy {
        struct clk_hw   clk480m_hw;
        struct phy      *phy;
        bool            uart_enabled;
+       struct reset_control *reset;
 };
 
 static int rockchip_usb_phy_power(struct rockchip_usb_phy *phy,
@@ -144,9 +146,23 @@ static int rockchip_usb_phy_power_on(struct phy *_phy)
        return clk_prepare_enable(phy->clk480m);
 }
 
+static int rockchip_usb_phy_reset(struct phy *_phy)
+{
+       struct rockchip_usb_phy *phy = phy_get_drvdata(_phy);
+
+       if (phy->reset) {
+               reset_control_assert(phy->reset);
+               udelay(10);
+               reset_control_deassert(phy->reset);
+       }
+
+       return 0;
+}
+
 static const struct phy_ops ops = {
        .power_on       = rockchip_usb_phy_power_on,
        .power_off      = rockchip_usb_phy_power_off,
+       .reset          = rockchip_usb_phy_reset,
        .owner          = THIS_MODULE,
 };
 
@@ -185,6 +201,10 @@ static int rockchip_usb_phy_init(struct 
rockchip_usb_phy_base *base,
                return -EINVAL;
        }
 
+       rk_phy->reset = of_reset_control_get(child, "phy-reset");
+       if (IS_ERR(rk_phy->reset))
+               rk_phy->reset = NULL;
+
        rk_phy->reg_offset = reg_offset;
 
        rk_phy->clk = of_clk_get_by_name(child, "phyclk");
-- 
2.7.4

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