1 files changed, 46 insertions, 1 deletions

diff --git a/drivers/usb/phy/phy-mxs-usb.c b/drivers/usb/phy/phy-mxs-usb.c
index eb746051eda4..c3177a1757ee 100644
--- a/drivers/usb/phy/phy-mxs-usb.c
+++ b/drivers/usb/phy/phy-mxs-usb.c
@@ -70,6 +70,9 @@
 #define ANADIG_USB2_LOOPBACK_SET                0x244
 #define ANADIG_USB2_LOOPBACK_CLR                0x248
 
+#define ANADIG_USB1_MISC                        0x1f0
+#define ANADIG_USB2_MISC                        0x250
+
 #define BM_ANADIG_ANA_MISC0_STOP_MODE_CONFIG    BIT(12)
 #define BM_ANADIG_ANA_MISC0_STOP_MODE_CONFIG_SL BIT(11)
 
@@ -81,6 +84,11 @@
 #define BM_ANADIG_USB2_LOOPBACK_UTMI_DIG_TST1   BIT(2)
 #define BM_ANADIG_USB2_LOOPBACK_TSTI_TX_EN      BIT(5)
 
+#define BM_ANADIG_USB1_MISC_RX_VPIN_FS          BIT(29)
+#define BM_ANADIG_USB1_MISC_RX_VMIN_FS          BIT(28)
+#define BM_ANADIG_USB2_MISC_RX_VPIN_FS          BIT(29)
+#define BM_ANADIG_USB2_MISC_RX_VMIN_FS          BIT(28)
+
 #define to_mxs_phy(p) container_of((p), struct mxs_phy, phy)
 
 /* Do disconnection between PHY and controller without vbus */
@@ -323,13 +331,50 @@ static void mxs_phy_shutdown(struct usb_phy *phy)
         clk_disable_unprepare(mxs_phy->clk);
 }
 
+static bool mxs_phy_is_low_speed_connection(struct mxs_phy *mxs_phy)
+{
+        unsigned int line_state;
+        /* bit definition is the same for all controllers */
+        unsigned int dp_bit = BM_ANADIG_USB1_MISC_RX_VPIN_FS,
+                     dm_bit = BM_ANADIG_USB1_MISC_RX_VMIN_FS;
+        unsigned int reg = ANADIG_USB1_MISC;
+
+        /* If the SoCs don't have anatop, quit */
+        if (!mxs_phy->regmap_anatop)
+                return false;
+
+        if (mxs_phy->port_id == 0)
+                reg = ANADIG_USB1_MISC;
+        else if (mxs_phy->port_id == 1)
+                reg = ANADIG_USB2_MISC;
+
+        regmap_read(mxs_phy->regmap_anatop, reg, &line_state);
+
+        if ((line_state & (dp_bit | dm_bit)) ==  dm_bit)
+                return true;
+        else
+                return false;
+}
+
 static int mxs_phy_suspend(struct usb_phy *x, int suspend)
 {
         int ret;
         struct mxs_phy *mxs_phy = to_mxs_phy(x);
+        bool low_speed_connection, vbus_is_on;
+
+        low_speed_connection = mxs_phy_is_low_speed_connection(mxs_phy);
+        vbus_is_on = mxs_phy_get_vbus_status(mxs_phy);
 
         if (suspend) {
-                writel(0xffffffff, x->io_priv + HW_USBPHY_PWD);
+                /*
+                 * FIXME: Do not power down RXPWD1PT1 bit for low speed
+                 * connect. The low speed connection will have problem at
+                 * very rare cases during usb suspend and resume process.
+                 */
+                if (low_speed_connection & vbus_is_on)
+                        writel(0xfffbffff, x->io_priv + HW_USBPHY_PWD);
+                else
+                        writel(0xffffffff, x->io_priv + HW_USBPHY_PWD);
                 writel(BM_USBPHY_CTRL_CLKGATE,
                        x->io_priv + HW_USBPHY_CTRL_SET);
                 clk_disable_unprepare(mxs_phy->clk);