usb: dwc2: gadget: Fix dwc2_restore_device_registers

Add parameter remote_wakeup to dwc2_restore_device_registers()
to be able to restore device registers according to programming
guide for dwc-otg. It says that in case of rem_wakeup DCTL must not
be restored here.

Remove setting of DCTL_PWRONPRGDONE from this function, because it
will be done in function responsible for exiting from hibernation.

WA for enabled EPx's IN and OUT in DDMA mode. On entering to
hibernation wrong value read and saved from DIEPDMAx,
as result BNA interrupt asserted on hibernation exit
by restoring from saved area.

Signed-off-by: Vardan Mikayelyan <mvardan@synopsys.com>
Signed-off-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Artur Petrosyan <arturp@synopsys.com>
Signed-off-by: Minas Harutyunyan <hminas@synopsys.com>
Signed-off-by: Grigor Tovmasyan <tovmasya@synopsys.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

drivers/usb/dwc2/core.c

@@ -165,7 +165,7 @@ int dwc2_exit_partial_power_down(struct dwc2_hsotg *hsotg, bool restore)
 				return ret;
 			}
 		} else {
-			ret = dwc2_restore_device_registers(hsotg);
+			ret = dwc2_restore_device_registers(hsotg, 0);
 			if (ret) {
 				dev_err(hsotg->dev, "%s: failed to restore device registers\n",
 					__func__);

drivers/usb/dwc2/core.h

@@ -1213,7 +1213,7 @@ void dwc2_hsotg_disconnect(struct dwc2_hsotg *dwc2);
 int dwc2_hsotg_set_test_mode(struct dwc2_hsotg *hsotg, int testmode);
 #define dwc2_is_device_connected(hsotg) (hsotg->connected)
 int dwc2_backup_device_registers(struct dwc2_hsotg *hsotg);
-int dwc2_restore_device_registers(struct dwc2_hsotg *hsotg);
+int dwc2_restore_device_registers(struct dwc2_hsotg *hsotg, int remote_wakeup);
 int dwc2_hsotg_tx_fifo_count(struct dwc2_hsotg *hsotg);
 int dwc2_hsotg_tx_fifo_total_depth(struct dwc2_hsotg *hsotg);
 int dwc2_hsotg_tx_fifo_average_depth(struct dwc2_hsotg *hsotg);
@@ -1237,7 +1237,8 @@ static inline int dwc2_hsotg_set_test_mode(struct dwc2_hsotg *hsotg,
 #define dwc2_is_device_connected(hsotg) (0)
 static inline int dwc2_backup_device_registers(struct dwc2_hsotg *hsotg)
 { return 0; }
-static inline int dwc2_restore_device_registers(struct dwc2_hsotg *hsotg)
+static inline int dwc2_restore_device_registers(struct dwc2_hsotg *hsotg,
+						int remote_wakeup)
 { return 0; }
 static inline int dwc2_hsotg_tx_fifo_count(struct dwc2_hsotg *hsotg)
 { return 0; }

drivers/usb/dwc2/gadget.c

@@ -4827,11 +4827,13 @@ int dwc2_backup_device_registers(struct dwc2_hsotg *hsotg)
  * if controller power were disabled.
  *
  * @hsotg: Programming view of the DWC_otg controller
+ * @remote_wakeup: Indicates whether resume is initiated by Device or Host.
+ *
+ * Return: 0 if successful, negative error code otherwise
  */
-int dwc2_restore_device_registers(struct dwc2_hsotg *hsotg)
+int dwc2_restore_device_registers(struct dwc2_hsotg *hsotg, int remote_wakeup)
 {
 	struct dwc2_dregs_backup *dr;
-	u32 dctl;
 	int i;
 
 	dev_dbg(hsotg->dev, "%s\n", __func__);
@@ -4845,30 +4847,42 @@ int dwc2_restore_device_registers(struct dwc2_hsotg *hsotg)
 	}
 	dr->valid = false;
 
-	dwc2_writel(dr->dcfg, hsotg->regs + DCFG);
-	dwc2_writel(dr->dctl, hsotg->regs + DCTL);
+	if (!remote_wakeup)
+		dwc2_writel(dr->dctl, hsotg->regs + DCTL);
+
 	dwc2_writel(dr->daintmsk, hsotg->regs + DAINTMSK);
 	dwc2_writel(dr->diepmsk, hsotg->regs + DIEPMSK);
 	dwc2_writel(dr->doepmsk, hsotg->regs + DOEPMSK);
 
 	for (i = 0; i < hsotg->num_of_eps; i++) {
 		/* Restore IN EPs */
-		dwc2_writel(dr->diepctl[i], hsotg->regs + DIEPCTL(i));
 		dwc2_writel(dr->dieptsiz[i], hsotg->regs + DIEPTSIZ(i));
 		dwc2_writel(dr->diepdma[i], hsotg->regs + DIEPDMA(i));
+		dwc2_writel(dr->doeptsiz[i], hsotg->regs + DOEPTSIZ(i));
+		/** WA for enabled EPx's IN in DDMA mode. On entering to
+		 * hibernation wrong value read and saved from DIEPDMAx,
+		 * as result BNA interrupt asserted on hibernation exit
+		 * by restoring from saved area.
+		 */
+		if (hsotg->params.g_dma_desc &&
+		    (dr->diepctl[i] & DXEPCTL_EPENA))
+			dr->diepdma[i] = hsotg->eps_in[i]->desc_list_dma;
 		dwc2_writel(dr->dtxfsiz[i], hsotg->regs + DPTXFSIZN(i));
-
+		dwc2_writel(dr->diepctl[i], hsotg->regs + DIEPCTL(i));
 		/* Restore OUT EPs */
-		dwc2_writel(dr->doepctl[i], hsotg->regs + DOEPCTL(i));
 		dwc2_writel(dr->doeptsiz[i], hsotg->regs + DOEPTSIZ(i));
+		/* WA for enabled EPx's OUT in DDMA mode. On entering to
+		 * hibernation wrong value read and saved from DOEPDMAx,
+		 * as result BNA interrupt asserted on hibernation exit
+		 * by restoring from saved area.
+		 */
+		if (hsotg->params.g_dma_desc &&
+		    (dr->doepctl[i] & DXEPCTL_EPENA))
+			dr->doepdma[i] = hsotg->eps_out[i]->desc_list_dma;
 		dwc2_writel(dr->doepdma[i], hsotg->regs + DOEPDMA(i));
+		dwc2_writel(dr->doepctl[i], hsotg->regs + DOEPCTL(i));
 	}
 
-	/* Set the Power-On Programming done bit */
-	dctl = dwc2_readl(hsotg->regs + DCTL);
-	dctl |= DCTL_PWRONPRGDONE;
-	dwc2_writel(dctl, hsotg->regs + DCTL);
-
 	return 0;
 }