usb: fotg210: Check role register in core

Read the role register and check that we are in host/peripheral
mode and issue warnings if we're not in the right role when
probing respective driver.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20230103-gemini-fotg210-usb-v2-5-100388af9810@linaro.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/fotg210/fotg210-core.c

@@ -18,6 +18,11 @@
 
 #include "fotg210.h"
 
+/* Role Register 0x80 */
+#define FOTG210_RR			0x80
+#define FOTG210_RR_ID			BIT(21) /* 1 = B-device, 0 = A-device */
+#define FOTG210_RR_CROLE		BIT(20) /* 1 = device, 0 = host */
+
 /*
  * Gemini-specific initialization function, only executed on the
  * Gemini SoC using the global misc control register.
@@ -95,6 +100,7 @@ static int fotg210_probe(struct platform_device *pdev)
 	struct device *dev = &pdev->dev;
 	enum usb_dr_mode mode;
 	struct fotg210 *fotg;
+	u32 val;
 	int ret;
 
 	fotg = devm_kzalloc(dev, sizeof(*fotg), GFP_KERNEL);
@@ -122,10 +128,16 @@ static int fotg210_probe(struct platform_device *pdev)
 			return ret;
 	}
 
-	if (mode == USB_DR_MODE_PERIPHERAL)
+	val = readl(fotg->base + FOTG210_RR);
+	if (mode == USB_DR_MODE_PERIPHERAL) {
+		if (!(val & FOTG210_RR_CROLE))
+			dev_err(dev, "block not in device role\n");
 		ret = fotg210_udc_probe(pdev, fotg);
-	else
+	} else {
+		if (val & FOTG210_RR_CROLE)
+			dev_err(dev, "block not in host role\n");
 		ret = fotg210_hcd_probe(pdev, fotg);
+	}
 
 	return ret;
 }