usb: dwc3: support new revisions of DWC3 core

Recent cores (>= 1.94a) have a set of new features,
commands and a slightly different programming model.

This patch aims to support those changes.

Signed-off-by: Paul Zimmerman <paulz@synopsys.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

1 files changed, 70 insertions, 13 deletions

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 852bde5cc139..04048333ec1a 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -100,6 +100,23 @@ int dwc3_gadget_set_link_state(struct dwc3 *dwc, enum dwc3_link_state state)
         int             retries = 10000;
         u32             reg;
 
+        /*
+         * Wait until device controller is ready. Only applies to 1.94a and
+         * later RTL.
+         */
+        if (dwc->revision >= DWC3_REVISION_194A) {
+                while (--retries) {
+                        reg = dwc3_readl(dwc->regs, DWC3_DSTS);
+                        if (reg & DWC3_DSTS_DCNRD)
+                                udelay(5);
+                        else
+                                break;
+                }
+
+                if (retries <= 0)
+                        return -ETIMEDOUT;
+        }
+
         reg = dwc3_readl(dwc->regs, DWC3_DCTL);
         reg &= ~DWC3_DCTL_ULSTCHNGREQ_MASK;
 
@@ -107,6 +124,13 @@ int dwc3_gadget_set_link_state(struct dwc3 *dwc, enum dwc3_link_state state)
         reg |= DWC3_DCTL_ULSTCHNGREQ(state);
         dwc3_writel(dwc->regs, DWC3_DCTL, reg);
 
+        /*
+         * The following code is racy when called from dwc3_gadget_wakeup,
+         * and is not needed, at least on newer versions
+         */
+        if (dwc->revision >= DWC3_REVISION_194A)
+                return 0;
+
         /* wait for a change in DSTS */
         retries = 10000;
         while (--retries) {
@@ -266,8 +290,8 @@ static const char *dwc3_gadget_ep_cmd_string(u8 cmd)
                 return "Clear Stall";
         case DWC3_DEPCMD_SETSTALL:
                 return "Set Stall";
-        case DWC3_DEPCMD_GETSEQNUMBER:
-                return "Get Data Sequence Number";
+        case DWC3_DEPCMD_GETEPSTATE:
+                return "Get Endpoint State";
         case DWC3_DEPCMD_SETTRANSFRESOURCE:
                 return "Set Endpoint Transfer Resource";
         case DWC3_DEPCMD_SETEPCONFIG:
@@ -1280,9 +1304,12 @@ static int dwc3_gadget_wakeup(struct usb_gadget *g)
                 goto out;
         }
 
-        /* write zeroes to Link Change Request */
-        reg &= ~DWC3_DCTL_ULSTCHNGREQ_MASK;
-        dwc3_writel(dwc->regs, DWC3_DCTL, reg);
+        /* Recent versions do this automatically */
+        if (dwc->revision < DWC3_REVISION_194A) {
+                /* write zeroes to Link Change Request */
+                reg &= ~DWC3_DCTL_ULSTCHNGREQ_MASK;
+                dwc3_writel(dwc->regs, DWC3_DCTL, reg);
+        }
 
         /* poll until Link State changes to ON */
         timeout = jiffies + msecs_to_jiffies(100);
@@ -1326,9 +1353,14 @@ static void dwc3_gadget_run_stop(struct dwc3 *dwc, int is_on)
 
         reg = dwc3_readl(dwc->regs, DWC3_DCTL);
         if (is_on) {
-                reg &= ~DWC3_DCTL_TRGTULST_MASK;
-                reg |= (DWC3_DCTL_RUN_STOP
-                                | DWC3_DCTL_TRGTULST_RX_DET);
+                if (dwc->revision <= DWC3_REVISION_187A) {
+                        reg &= ~DWC3_DCTL_TRGTULST_MASK;
+                        reg |= DWC3_DCTL_TRGTULST_RX_DET;
+                }
+
+                if (dwc->revision >= DWC3_REVISION_194A)
+                        reg &= ~DWC3_DCTL_KEEP_CONNECT;
+                reg |= DWC3_DCTL_RUN_STOP;
         } else {
                 reg &= ~DWC3_DCTL_RUN_STOP;
         }
@@ -1468,6 +1500,7 @@ static int dwc3_gadget_stop(struct usb_gadget *g,
 
         return 0;
 }
+
 static const struct usb_gadget_ops dwc3_gadget_ops = {
         .get_frame              = dwc3_gadget_get_frame,
         .wakeup                 = dwc3_gadget_wakeup,
@@ -1962,9 +1995,12 @@ static void dwc3_gadget_reset_interrupt(struct dwc3 *dwc)
         /* after reset -> Default State */
         dwc->dev_state = DWC3_DEFAULT_STATE;
 
-        /* Resume PHYs */
-        dwc3_gadget_usb2_phy_suspend(dwc, false);
-        dwc3_gadget_usb3_phy_suspend(dwc, false);
+        /* Recent versions support automatic phy suspend and don't need this */
+        if (dwc->revision < DWC3_REVISION_194A) {
+                /* Resume PHYs */
+                dwc3_gadget_usb2_phy_suspend(dwc, false);
+                dwc3_gadget_usb3_phy_suspend(dwc, false);
+        }
 
         if (dwc->gadget.speed != USB_SPEED_UNKNOWN)
                 dwc3_disconnect_gadget(dwc);
@@ -2082,8 +2118,11 @@ static void dwc3_gadget_conndone_interrupt(struct dwc3 *dwc)
                 break;
         }
 
-        /* Suspend unneded PHY */
-        dwc3_gadget_phy_suspend(dwc, dwc->gadget.speed);
+        /* Recent versions support automatic phy suspend and don't need this */
+        if (dwc->revision < DWC3_REVISION_194A) {
+                /* Suspend unneeded PHY */
+                dwc3_gadget_phy_suspend(dwc, dwc->gadget.speed);
+        }
 
         dep = dwc->eps[0];
         ret = __dwc3_gadget_ep_enable(dep, &dwc3_gadget_ep0_desc, NULL);
@@ -2389,6 +2428,24 @@ int __devinit dwc3_gadget_init(struct dwc3 *dwc)
                         DWC3_DEVTEN_DISCONNEVTEN);
         dwc3_writel(dwc->regs, DWC3_DEVTEN, reg);
 
+        /* Enable USB2 LPM and automatic phy suspend only on recent versions */
+        if (dwc->revision >= DWC3_REVISION_194A) {
+                reg = dwc3_readl(dwc->regs, DWC3_DCFG);
+                reg |= DWC3_DCFG_LPM_CAP;
+                dwc3_writel(dwc->regs, DWC3_DCFG, reg);
+
+                reg = dwc3_readl(dwc->regs, DWC3_DCTL);
+                reg &= ~(DWC3_DCTL_HIRD_THRES_MASK | DWC3_DCTL_L1_HIBER_EN);
+
+                /* TODO: This should be configurable */
+                reg |= DWC3_DCTL_HIRD_THRES(31);
+
+                dwc3_writel(dwc->regs, DWC3_DCTL, reg);
+
+                dwc3_gadget_usb2_phy_suspend(dwc, true);
+                dwc3_gadget_usb3_phy_suspend(dwc, true);
+        }
+
         ret = device_register(&dwc->gadget.dev);
         if (ret) {
                 dev_err(dwc->dev, "failed to register gadget device\n");