3 files changed, 49 insertions, 0 deletions

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index a1f99c3b5f37..f0a9bb5754a3 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -781,6 +781,24 @@ static int dwc3_hs_phy_setup(struct dwc3 *dwc, int index)
 	return 0;
 }
 
+static void dwc3_ulpi_setup(struct dwc3 *dwc)
+{
+	int index;
+	u32 reg;
+
+	/* Don't do anything if there is no ULPI PHY */
+	if (!dwc->ulpi)
+		return;
+
+	if (dwc->enable_usb2_transceiver_delay) {
+		for (index = 0; index < dwc->num_usb2_ports; index++) {
+			reg = dwc3_readl(dwc, DWC3_GUSB2PHYCFG(index));
+			reg |= DWC3_GUSB2PHYCFG_XCVRDLY;
+			dwc3_writel(dwc, DWC3_GUSB2PHYCFG(index), reg);
+		}
+	}
+}
+
 /**
  * dwc3_phy_setup - Configure USB PHY Interface of DWC3 Core
  * @dwc: Pointer to our controller context structure
@@ -1355,6 +1373,8 @@ static int dwc3_core_init(struct dwc3 *dwc)
 		dwc->ulpi_ready = true;
 	}
 
+	dwc3_ulpi_setup(dwc);
+
 	if (!dwc->phys_ready) {
 		ret = dwc3_core_get_phy(dwc);
 		if (ret)
diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index a35b3db1f9f3..a39bf284c763 100644
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -302,6 +302,7 @@
 #define DWC3_GUSB2PHYCFG_SUSPHY		BIT(6)
 #define DWC3_GUSB2PHYCFG_ULPI_UTMI	BIT(4)
 #define DWC3_GUSB2PHYCFG_ENBLSLPM	BIT(8)
+#define DWC3_GUSB2PHYCFG_XCVRDLY	BIT(9)
 #define DWC3_GUSB2PHYCFG_PHYIF(n)	(n << 3)
 #define DWC3_GUSB2PHYCFG_PHYIF_MASK	DWC3_GUSB2PHYCFG_PHYIF(1)
 #define DWC3_GUSB2PHYCFG_USBTRDTIM(n)	(n << 10)
@@ -1161,6 +1162,8 @@ struct dwc3_glue_ops {
  *	3	- Reserved
  * @dis_metastability_quirk: set to disable metastability quirk.
  * @dis_split_quirk: set to disable split boundary.
+ * @enable_usb2_transceiver_delay: Set to insert a delay before the
+ *			assertion of the TxValid signal during a HS Chirp.
  * @sys_wakeup: set if the device may do system wakeup.
  * @wakeup_configured: set if the device is configured for remote wakeup.
  * @suspended: set to track suspend event due to U3/L2.
@@ -1403,6 +1406,7 @@ struct dwc3 {
 	unsigned		dis_metastability_quirk:1;
 
 	unsigned		dis_split_quirk:1;
+	unsigned		enable_usb2_transceiver_delay:1;
 	unsigned		async_callbacks:1;
 	unsigned		sys_wakeup:1;
 	unsigned		wakeup_configured:1;
diff --git a/drivers/usb/dwc3/ulpi.c b/drivers/usb/dwc3/ulpi.c
index 57daad15f502..a256b7f5d78b 100644
--- a/drivers/usb/dwc3/ulpi.c
+++ b/drivers/usb/dwc3/ulpi.c
@@ -10,10 +10,13 @@
 #include <linux/delay.h>
 #include <linux/time64.h>
 #include <linux/ulpi/regs.h>
+#include <linux/ulpi/driver.h>
 
 #include "core.h"
 #include "io.h"
 
+#define USB_VENDOR_MICROCHIP 0x0424
+
 #define DWC3_ULPI_ADDR(a) \
 		((a >= ULPI_EXT_VENDOR_SPECIFIC) ? \
 		DWC3_GUSB2PHYACC_ADDR(ULPI_ACCESS_EXTENDED) | \
@@ -83,6 +86,26 @@ static const struct ulpi_ops dwc3_ulpi_ops = {
 	.write = dwc3_ulpi_write,
 };
 
+static void dwc3_ulpi_detect_config(struct dwc3 *dwc)
+{
+	struct ulpi *ulpi = dwc->ulpi;
+
+	switch (ulpi->id.vendor) {
+	case USB_VENDOR_MICROCHIP:
+		switch (ulpi->id.product) {
+		case 0x0009:
+			/* Microchip USB3340 ULPI PHY */
+			dwc->enable_usb2_transceiver_delay = true;
+			break;
+		default:
+			break;
+		}
+		break;
+	default:
+		break;
+	}
+}
+
 int dwc3_ulpi_init(struct dwc3 *dwc)
 {
 	/* Register the interface */
@@ -92,6 +115,8 @@ int dwc3_ulpi_init(struct dwc3 *dwc)
 		return PTR_ERR(dwc->ulpi);
 	}
 
+	dwc3_ulpi_detect_config(dwc);
+
 	return 0;
 }