usb: dwc2: Remove version check in GSNPSID

Only check the ID portion of the GSNPSID register and don’t check
the version. This will allow the driver to work with version 4.00a
and later of the DWC_hsotg IP.

Acked-by: John Youn <johnyoun@synopsys.com>
Signed-off-by: Gevorg Sahakyan <sahakyan@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.h

@@ -956,6 +956,11 @@ struct dwc2_hsotg {
 #define DWC2_FS_IOT_REV_1_00a	0x5531100a
 #define DWC2_HS_IOT_REV_1_00a	0x5532100a
 
+	/* DWC OTG HW Core ID */
+#define DWC2_OTG_ID		0x4f540000
+#define DWC2_FS_IOT_ID		0x55310000
+#define DWC2_HS_IOT_ID		0x55320000
+
 #if IS_ENABLED(CONFIG_USB_DWC2_HOST) || IS_ENABLED(CONFIG_USB_DWC2_DUAL_ROLE)
 	union dwc2_hcd_internal_flags {
 		u32 d32;

drivers/usb/dwc2/hw.h

@@ -231,6 +231,7 @@
 #define GUID				HSOTG_REG(0x003c)
 #define GSNPSID				HSOTG_REG(0x0040)
 #define GHWCFG1				HSOTG_REG(0x0044)
+#define GSNPSID_ID_MASK			GENMASK(31, 16)
 
 #define GHWCFG2				HSOTG_REG(0x0048)
 #define GHWCFG2_OTG_ENABLE_IC_USB		BIT(31)

drivers/usb/dwc2/params.c

@@ -646,14 +646,13 @@ int dwc2_get_hwparams(struct dwc2_hsotg *hsotg)
 	/*
 	 * Attempt to ensure this device is really a DWC_otg Controller.
 	 * Read and verify the GSNPSID register contents. The value should be
-	 * 0x45f42xxx or 0x45f43xxx, which corresponds to either "OT2" or "OT3",
-	 * as in "OTG version 2.xx" or "OTG version 3.xx".
+	 * 0x45f4xxxx, 0x5531xxxx or 0x5532xxxx
 	 */
+
 	hw->snpsid = dwc2_readl(hsotg->regs + GSNPSID);
-	if ((hw->snpsid & 0xfffff000) != 0x4f542000 &&
-	    (hw->snpsid & 0xfffff000) != 0x4f543000 &&
-	    (hw->snpsid & 0xffff0000) != 0x55310000 &&
-	    (hw->snpsid & 0xffff0000) != 0x55320000) {
+	if ((hw->snpsid & GSNPSID_ID_MASK) != DWC2_OTG_ID &&
+	    (hw->snpsid & GSNPSID_ID_MASK) != DWC2_FS_IOT_ID &&
+	    (hw->snpsid & GSNPSID_ID_MASK) != DWC2_HS_IOT_ID) {
 		dev_err(hsotg->dev, "Bad value for GSNPSID: 0x%08x\n",
 			hw->snpsid);
 		return -ENODEV;