usb: dwc2: add support for STM32MP15 SoCs USB OTG HS and FS

This patch introduces a new parameter to activate external ID pin and valid
vbus level detection, required on STM32MP15 SoC to support dual role,
either in HS or FS.
The STM32MP15 SoC uses the GGPIO register to enable the level detection.
The level detector requires to be powered.
Also adds the params structures for STM32MP15 OTG HS and STM32MP1 OTG FS.

Acked-by: Minas Harutyunyan <hminas@synopsys.com>
Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>

1 files changed, 92 insertions, 2 deletions

diff --git a/drivers/usb/dwc2/platform.c b/drivers/usb/dwc2/platform.c
index 3c6ce09a6db5..8368d6d66d64 100644
--- a/drivers/usb/dwc2/platform.c
+++ b/drivers/usb/dwc2/platform.c
@@ -312,6 +312,9 @@ static int dwc2_driver_remove(struct platform_device *dev)
 	if (hsotg->gadget_enabled)
 		dwc2_hsotg_remove(hsotg);
 
+	if (hsotg->params.activate_stm_id_vb_detection)
+		regulator_disable(hsotg->usb33d);
+
 	if (hsotg->ll_hw_enabled)
 		dwc2_lowlevel_hw_disable(hsotg);
 
@@ -464,10 +467,35 @@ static int dwc2_driver_probe(struct platform_device *dev)
 	if (retval)
 		goto error;
 
+	if (hsotg->params.activate_stm_id_vb_detection) {
+		u32 ggpio;
+
+		hsotg->usb33d = devm_regulator_get(hsotg->dev, "usb33d");
+		if (IS_ERR(hsotg->usb33d)) {
+			retval = PTR_ERR(hsotg->usb33d);
+			if (retval != -EPROBE_DEFER)
+				dev_err(hsotg->dev,
+					"failed to request usb33d supply: %d\n",
+					retval);
+			goto error;
+		}
+		retval = regulator_enable(hsotg->usb33d);
+		if (retval) {
+			dev_err(hsotg->dev,
+				"failed to enable usb33d supply: %d\n", retval);
+			goto error;
+		}
+
+		ggpio = dwc2_readl(hsotg, GGPIO);
+		ggpio |= GGPIO_STM32_OTG_GCCFG_IDEN;
+		ggpio |= GGPIO_STM32_OTG_GCCFG_VBDEN;
+		dwc2_writel(hsotg, ggpio, GGPIO);
+	}
+
 	if (hsotg->dr_mode != USB_DR_MODE_HOST) {
 		retval = dwc2_gadget_init(hsotg);
 		if (retval)
-			goto error;
+			goto error_init;
 		hsotg->gadget_enabled = 1;
 	}
 
@@ -493,7 +521,7 @@ static int dwc2_driver_probe(struct platform_device *dev)
 		if (retval) {
 			if (hsotg->gadget_enabled)
 				dwc2_hsotg_remove(hsotg);
-			goto error;
+			goto error_init;
 		}
 		hsotg->hcd_enabled = 1;
 	}
@@ -509,6 +537,9 @@ static int dwc2_driver_probe(struct platform_device *dev)
 
 	return 0;
 
+error_init:
+	if (hsotg->params.activate_stm_id_vb_detection)
+		regulator_disable(hsotg->usb33d);
 error:
 	dwc2_lowlevel_hw_disable(hsotg);
 	return retval;
@@ -523,6 +554,37 @@ static int __maybe_unused dwc2_suspend(struct device *dev)
 	if (is_device_mode)
 		dwc2_hsotg_suspend(dwc2);
 
+	if (dwc2->params.activate_stm_id_vb_detection) {
+		unsigned long flags;
+		u32 ggpio, gotgctl;
+
+		/*
+		 * Need to force the mode to the current mode to avoid Mode
+		 * Mismatch Interrupt when ID detection will be disabled.
+		 */
+		dwc2_force_mode(dwc2, !is_device_mode);
+
+		spin_lock_irqsave(&dwc2->lock, flags);
+		gotgctl = dwc2_readl(dwc2, GOTGCTL);
+		/* bypass debounce filter, enable overrides */
+		gotgctl |= GOTGCTL_DBNCE_FLTR_BYPASS;
+		gotgctl |= GOTGCTL_BVALOEN | GOTGCTL_AVALOEN;
+		/* Force A / B session if needed */
+		if (gotgctl & GOTGCTL_ASESVLD)
+			gotgctl |= GOTGCTL_AVALOVAL;
+		if (gotgctl & GOTGCTL_BSESVLD)
+			gotgctl |= GOTGCTL_BVALOVAL;
+		dwc2_writel(dwc2, gotgctl, GOTGCTL);
+		spin_unlock_irqrestore(&dwc2->lock, flags);
+
+		ggpio = dwc2_readl(dwc2, GGPIO);
+		ggpio &= ~GGPIO_STM32_OTG_GCCFG_IDEN;
+		ggpio &= ~GGPIO_STM32_OTG_GCCFG_VBDEN;
+		dwc2_writel(dwc2, ggpio, GGPIO);
+
+		regulator_disable(dwc2->usb33d);
+	}
+
 	if (dwc2->ll_hw_enabled &&
 	    (is_device_mode || dwc2_host_can_poweroff_phy(dwc2))) {
 		ret = __dwc2_lowlevel_hw_disable(dwc2);
@@ -544,6 +606,34 @@ static int __maybe_unused dwc2_resume(struct device *dev)
 	}
 	dwc2->phy_off_for_suspend = false;
 
+	if (dwc2->params.activate_stm_id_vb_detection) {
+		unsigned long flags;
+		u32 ggpio, gotgctl;
+
+		ret = regulator_enable(dwc2->usb33d);
+		if (ret)
+			return ret;
+
+		ggpio = dwc2_readl(dwc2, GGPIO);
+		ggpio |= GGPIO_STM32_OTG_GCCFG_IDEN;
+		ggpio |= GGPIO_STM32_OTG_GCCFG_VBDEN;
+		dwc2_writel(dwc2, ggpio, GGPIO);
+
+		/* ID/VBUS detection startup time */
+		usleep_range(5000, 7000);
+
+		spin_lock_irqsave(&dwc2->lock, flags);
+		gotgctl = dwc2_readl(dwc2, GOTGCTL);
+		gotgctl &= ~GOTGCTL_DBNCE_FLTR_BYPASS;
+		gotgctl &= ~(GOTGCTL_BVALOEN | GOTGCTL_AVALOEN |
+			     GOTGCTL_BVALOVAL | GOTGCTL_AVALOVAL);
+		dwc2_writel(dwc2, gotgctl, GOTGCTL);
+		spin_unlock_irqrestore(&dwc2->lock, flags);
+	}
+
+	/* Need to restore FORCEDEVMODE/FORCEHOSTMODE */
+	dwc2_force_dr_mode(dwc2);
+
 	if (dwc2_is_device_mode(dwc2))
 		ret = dwc2_hsotg_resume(dwc2);