Merge branch 'bits/040-dwc3' into asahi-wip

Author: jannau

Documentation/devicetree/bindings/usb/apple,dwc3.yaml

@@ -0,0 +1,64 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/usb/apple,dwc3.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Apple Silicon DWC3 USB controller
+
+maintainers:
+  - Sven Peter <sven@svenpeter.dev>
+
+description:
+  On Apple Silicon SoCs such as the M1 each Type-C port has a corresponding
+  USB controller based on the Synopsys DesignWare USB3 controller.
+
+  The common content of this binding is defined in snps,dwc3.yaml.
+
+allOf:
+  - $ref: snps,dwc3.yaml#
+
+select:
+  properties:
+    compatible:
+      contains:
+        const: apple,dwc3
+  required:
+    - compatible
+
+properties:
+  compatible:
+    items:
+      - enum:
+          - apple,t8103-dwc3
+          - apple,t6000-dwc3
+      - const: apple,dwc3
+      - const: snps,dwc3
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+unevaluatedProperties: false
+
+required:
+  - compatible
+  - reg
+  - interrupts
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/apple-aic.h>
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    usb@82280000 {
+      compatible = "apple,t8103-dwc3", "apple,dwc3", "snps,dwc3";
+      reg = <0x82280000 0x10000>;
+      interrupts = <AIC_IRQ 777 IRQ_TYPE_LEVEL_HIGH>;
+
+      dr_mode = "otg";
+      usb-role-switch;
+      role-switch-default-mode = "host";
+    };

drivers/usb/dwc3/core.c

@@ -156,6 +156,9 @@ void dwc3_set_prtcap(struct dwc3 *dwc, u32 mode, bool ignore_susphy)
 	dwc->current_dr_role = mode;
 }
 
+static void dwc3_core_exit(struct dwc3 *dwc);
+static int dwc3_core_init_for_resume(struct dwc3 *dwc);
+
 static void __dwc3_set_mode(struct work_struct *work)
 {
 	struct dwc3 *dwc = work_to_dwc(work);
@@ -175,7 +178,7 @@ static void __dwc3_set_mode(struct work_struct *work)
 	if (dwc->current_dr_role == DWC3_GCTL_PRTCAP_OTG)
 		dwc3_otg_update(dwc, 0);
 
-	if (!desired_dr_role)
+	if (!desired_dr_role && !dwc->role_switch_reset_quirk)
 		goto out;
 
 	if (desired_dr_role == dwc->current_dr_role)
@@ -203,13 +206,32 @@ static void __dwc3_set_mode(struct work_struct *work)
 		break;
 	}
 
+	if (dwc->role_switch_reset_quirk) {
+		if (dwc->current_dr_role) {
+			dwc->current_dr_role = 0;
+			dwc3_core_exit(dwc);
+		}
+
+		if (desired_dr_role) {
+			ret = dwc3_core_init_for_resume(dwc);
+			if (ret) {
+				dev_err(dwc->dev,
+				    "failed to reinitialize core\n");
+				goto out;
+			}
+		} else {
+			goto out;
+		}
+	}
+
 	/*
 	 * When current_dr_role is not set, there's no role switching.
 	 * Only perform GCTL.CoreSoftReset when there's DRD role switching.
 	 */
-	if (dwc->current_dr_role && ((DWC3_IP_IS(DWC3) ||
+	if (dwc->role_switch_reset_quirk ||
+		(dwc->current_dr_role && ((DWC3_IP_IS(DWC3) ||
 			DWC3_VER_IS_PRIOR(DWC31, 190A)) &&
-			desired_dr_role != DWC3_GCTL_PRTCAP_OTG)) {
+			desired_dr_role != DWC3_GCTL_PRTCAP_OTG))) {
 		reg = dwc3_readl(dwc->regs, DWC3_GCTL);
 		reg |= DWC3_GCTL_CORESOFTRESET;
 		dwc3_writel(dwc->regs, DWC3_GCTL, reg);
@@ -1370,6 +1392,9 @@ static int dwc3_core_init(struct dwc3 *dwc)
 	if (ret)
 		goto err_exit_phy;
 
+	if (dwc->role_switch_reset_quirk)
+		dwc3_enable_susphy(dwc, true);
+
 	dwc3_core_setup_global_control(dwc);
 	dwc3_core_num_eps(dwc);
 
@@ -1613,6 +1638,18 @@ static int dwc3_core_init_mode(struct dwc3 *dwc)
 		ret = dwc3_drd_init(dwc);
 		if (ret)
 			return dev_err_probe(dev, ret, "failed to initialize dual-role\n");
+
+		/*
+		 * If the role switch reset quirk is required the first role
+		 * switch notification will initialize the core such that we
+		 * have to shut it down here. Make sure that the __dwc3_set_mode
+		 * queued by dwc3_drd_init has completed before since it
+		 * may still try to access MMIO.
+		 */
+		if (dwc->role_switch_reset_quirk) {
+			flush_work(&dwc->drd_work);
+			dwc3_core_exit(dwc);
+		}
 		break;
 	default:
 		dev_err(dev, "Unsupported mode of operation %d\n", dwc->dr_mode);
@@ -2198,6 +2235,23 @@ static int dwc3_probe(struct platform_device *pdev)
 	if (ret)
 		goto err_put_psy;
 
+	if (dev->of_node) {
+		if (of_device_is_compatible(dev->of_node, "apple,dwc3")) {
+			if (!IS_ENABLED(CONFIG_USB_ROLE_SWITCH) ||
+			    !IS_ENABLED(CONFIG_USB_DWC3_DUAL_ROLE)) {
+				dev_err(dev,
+				    "Apple DWC3 requires role switch support.\n"
+				    );
+				ret = -EINVAL;
+				goto err_put_psy;
+			}
+
+			dwc->dr_mode = USB_DR_MODE_OTG;
+			dwc->role_switch_reset_quirk = true;
+			dwc->no_early_roothub_poweroff = true;
+		}
+	}
+
 	ret = reset_control_deassert(dwc->reset);
 	if (ret)
 		goto err_put_psy;
@@ -2337,7 +2391,6 @@ static void dwc3_remove(struct platform_device *pdev)
 		power_supply_put(dwc->usb_psy);
 }
 
-#ifdef CONFIG_PM
 static int dwc3_core_init_for_resume(struct dwc3 *dwc)
 {
 	int ret;
@@ -2364,6 +2417,7 @@ static int dwc3_core_init_for_resume(struct dwc3 *dwc)
 	return ret;
 }
 
+#ifdef CONFIG_PM
 static int dwc3_suspend_common(struct dwc3 *dwc, pm_message_t msg)
 {
 	u32 reg;

drivers/usb/dwc3/core.h

@@ -1151,6 +1151,8 @@ struct dwc3_scratchpad_array {
  * @suspended: set to track suspend event due to U3/L2.
  * @susphy_state: state of DWC3_GUSB2PHYCFG_SUSPHY + DWC3_GUSB3PIPECTL_SUSPHY
  *		  before PM suspend.
+ * @role_switch_reset_quirk: set to force reinitialization after any role switch
+ * @no_early_roothub_poweroff: set to skip early root hub port power off
  * @imod_interval: set the interrupt moderation interval in 250ns
  *			increments or 0 to disable.
  * @max_cfg_eps: current max number of IN eps used across all USB configs.
@@ -1385,6 +1387,9 @@ struct dwc3 {
 	unsigned		suspended:1;
 	unsigned		susphy_state:1;
 
+	unsigned		role_switch_reset_quirk:1;
+	unsigned		no_early_roothub_poweroff:1;
+
 	u16			imod_interval;
 
 	int			max_cfg_eps;

drivers/usb/dwc3/drd.c

@@ -464,6 +464,9 @@ static int dwc3_usb_role_switch_set(struct usb_role_switch *sw,
 		break;
 	}
 
+	if (dwc->role_switch_reset_quirk && role == USB_ROLE_NONE)
+		mode = 0;
+
 	dwc3_set_mode(dwc, mode);
 	return 0;
 }
@@ -492,6 +495,10 @@ static enum usb_role dwc3_usb_role_switch_get(struct usb_role_switch *sw)
 			role = USB_ROLE_DEVICE;
 		break;
 	}
+
+	if (dwc->role_switch_reset_quirk && !dwc->current_dr_role)
+		role = USB_ROLE_NONE;
+
 	spin_unlock_irqrestore(&dwc->lock, flags);
 	return role;
 }
@@ -502,7 +509,9 @@ static int dwc3_setup_role_switch(struct dwc3 *dwc)
 	u32 mode;
 
 	dwc->role_switch_default_mode = usb_get_role_switch_default_mode(dwc->dev);
-	if (dwc->role_switch_default_mode == USB_DR_MODE_HOST) {
+	if (dwc->role_switch_reset_quirk) {
+		mode = 0;
+	} else if (dwc->role_switch_default_mode == USB_DR_MODE_HOST) {
 		mode = DWC3_GCTL_PRTCAP_HOST;
 	} else {
 		dwc->role_switch_default_mode = USB_DR_MODE_PERIPHERAL;

drivers/usb/dwc3/host.c

@@ -134,8 +134,11 @@ int dwc3_host_init(struct dwc3 *dwc)
 	/*
 	 * Some platforms need to power off all Root hub ports immediately after DWC3 set to host
 	 * mode to avoid VBUS glitch happen when xhci get reset later.
+	 * On Apple platforms we must not touch any MMIO yet because dwc3
+	 * will not work correctly before its PHY has been initialized.
 	 */
-	dwc3_power_off_all_roothub_ports(dwc);
+	if (!dwc->no_early_roothub_poweroff)
+		dwc3_power_off_all_roothub_ports(dwc);
 
 	irq = dwc3_host_get_irq(dwc);
 	if (irq < 0)
@@ -220,7 +223,8 @@ void dwc3_host_exit(struct dwc3 *dwc)
 	if (dwc->sys_wakeup)
 		device_init_wakeup(&dwc->xhci->dev, false);
 
-	dwc3_enable_susphy(dwc, false);
+	if (!dwc->role_switch_reset_quirk)
+		dwc3_enable_susphy(dwc, false);
 	platform_device_unregister(dwc->xhci);
 	dwc->xhci = NULL;
 }