dwc3: Add code for supporting entering into D3 state during suspend

[vajnamar/linux-xlnx.git] / drivers / usb / dwc3 / dwc3-of-simple.c

diff --git a/drivers/usb/dwc3/dwc3-of-simple.c b/drivers/usb/dwc3/dwc3-of-simple.c
index 4233923a2a7793e1814a654f1ee1cc8e48ff8705..e5bf8c939fd11f06556ab0a134298c7bdbdd570c 100644 (file)
--- a/drivers/usb/dwc3/dwc3-of-simple.c
+++ b/drivers/usb/dwc3/dwc3-of-simple.c
@@ -46,6 +46,22 @@
 #define ULPI_OTG_CTRL_CLEAR            0XC
 #define OTG_CTRL_DRVVBUS_OFFSET                5
 
+#define XLNX_USB_CUR_PWR_STATE          0x0000
+#define XLNX_CUR_PWR_STATE_D0           0x00
+#define XLNX_CUR_PWR_STATE_D3           0x0F
+#define XLNX_CUR_PWR_STATE_BITMASK      0x0F
+
+#define XLNX_USB_PME_ENABLE             0x0034
+#define XLNX_PME_ENABLE_SIG_GEN         0x01
+
+#define XLNX_USB_REQ_PWR_STATE          0x003c
+#define XLNX_REQ_PWR_STATE_D0           0x00
+#define XLNX_REQ_PWR_STATE_D3           0x03
+
+/* Number of retries for USB operations */
+#define DWC3_PWR_STATE_RETRIES          1000
+#define DWC3_PWR_TIMEOUT               100
+
 #define DWC3_OF_ADDRESS(ADDR)          ((ADDR) - DWC3_GLOBALS_REGS_START)
 
 struct dwc3_of_simple {
@@ -56,6 +72,8 @@ struct dwc3_of_simple {
        struct dwc3             *dwc;
        bool                    wakeup_capable;
        bool                    dis_u3_susphy_quirk;
+       bool                    enable_d3_suspend;
+       char                    soc_rev;
 };
 
 void dwc3_set_phydata(struct device *dev, struct phy *phy)
@@ -159,6 +177,9 @@ void dwc3_simple_wakeup_capable(struct device *dev, bool wakeup)
 
                /* Set wakeup capable as true or false */
                simple->wakeup_capable = wakeup;
+
+               /* Allow D3 state if wakeup capable only */
+               simple->enable_d3_suspend = wakeup;
        }
 }
 EXPORT_SYMBOL(dwc3_simple_wakeup_capable);
@@ -256,6 +277,9 @@ static int dwc3_of_simple_probe(struct platform_device *pdev)
                        simple->dis_u3_susphy_quirk = true;
                }
 
+               /* Update soc_rev to simple for future use */
+               simple->soc_rev = *soc_rev;
+
                /* Clean soc_rev if got a valid pointer from nvmem driver
                 * else we may end up in kernel panic
                 */
@@ -326,6 +350,77 @@ static void dwc3_simple_vbus(struct dwc3 *dwc, bool vbus_off)
        writel(reg, dwc->regs + addr);
 }
 
+int dwc3_set_usb_core_power(struct dwc3 *dwc, bool on)
+{
+       u32 reg, retries;
+       void __iomem *reg_base;
+       struct platform_device *pdev_parent;
+       struct dwc3_of_simple *simple;
+       struct device_node *node = of_get_parent(dwc->dev->of_node);
+
+       /* this is for Xilinx devices only */
+       if (!of_device_is_compatible(node, "xlnx,zynqmp-dwc3"))
+               return 0;
+
+       pdev_parent = of_find_device_by_node(node);
+       simple = platform_get_drvdata(pdev_parent);
+       reg_base = simple->regs;
+
+       /* Check if entering into D3 state is allowed during suspend */
+       if ((simple->soc_rev < ZYNQMP_SILICON_V4) || !simple->enable_d3_suspend)
+               return 0;
+
+       if (on) {
+               dev_dbg(dwc->dev, "trying to set power state to D0....\n");
+
+               /* change power state to D0 */
+               writel(XLNX_REQ_PWR_STATE_D0,
+                      reg_base + XLNX_USB_REQ_PWR_STATE);
+
+               /* wait till current state is changed to D0 */
+               retries = DWC3_PWR_STATE_RETRIES;
+               do {
+                       reg = readl(reg_base + XLNX_USB_CUR_PWR_STATE);
+                       if ((reg & XLNX_CUR_PWR_STATE_BITMASK) ==
+                            XLNX_CUR_PWR_STATE_D0)
+                               break;
+
+                       usleep_range(DWC3_PWR_TIMEOUT, DWC3_PWR_TIMEOUT * 2);
+               } while (--retries);
+
+               if (!retries) {
+                       dev_err(dwc->dev, "Failed to set power state to D0\n");
+                       return -EIO;
+               }
+       } else {
+               dev_dbg(dwc->dev, "Trying to set power state to D3...\n");
+
+               /* enable PME to wakeup from hibernation */
+               writel(XLNX_PME_ENABLE_SIG_GEN, reg_base + XLNX_USB_PME_ENABLE);
+
+               /* change power state to D3 */
+               writel(XLNX_REQ_PWR_STATE_D3,
+                      reg_base + XLNX_USB_REQ_PWR_STATE);
+
+               /* wait till current state is changed to D3 */
+               retries = DWC3_PWR_STATE_RETRIES;
+               do {
+                       reg = readl(reg_base + XLNX_USB_CUR_PWR_STATE);
+                       if ((reg & XLNX_CUR_PWR_STATE_BITMASK) ==
+                                       XLNX_CUR_PWR_STATE_D3)
+                               break;
+
+                       usleep_range(DWC3_PWR_TIMEOUT, DWC3_PWR_TIMEOUT * 2);
+               } while (--retries);
+
+               if (!retries)
+                       dev_err(dwc->dev, "Failed to set power state to D3\n");
+       }
+
+       return 0;
+}
+EXPORT_SYMBOL(dwc3_set_usb_core_power);
+
 static int dwc3_of_simple_suspend(struct device *dev)
 {
        struct dwc3_of_simple   *simple = dev_get_drvdata(dev);