[PATCH] [RFC] usb: gadget: avoid unusual inline assembly

Arnd Bergmann arnd at kernel.org
Mon Sep 27 05:38:20 PDT 2021


From: Arnd Bergmann <arnd at arndb.de>

clang does not understand the "mrc%?" syntax:

drivers/usb/gadget/udc/pxa25x_udc.c:2330:11: error: invalid % escape in inline assembly string

I don't understand it either, but removing the %? here gets it to build.
This is probably wrong and someone else should do a proper patch.

Any suggestions?

Signed-off-by: Arnd Bergmann <arnd at arndb.de>
---
 drivers/usb/gadget/udc/pxa25x_udc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/gadget/udc/pxa25x_udc.c b/drivers/usb/gadget/udc/pxa25x_udc.c
index a09ec1d826b2..52cdfd8212d6 100644
--- a/drivers/usb/gadget/udc/pxa25x_udc.c
+++ b/drivers/usb/gadget/udc/pxa25x_udc.c
@@ -2325,7 +2325,7 @@ static int pxa25x_udc_probe(struct platform_device *pdev)
 	pr_info("%s: version %s\n", driver_name, DRIVER_VERSION);
 
 	/* insist on Intel/ARM/XScale */
-	asm("mrc%? p15, 0, %0, c0, c0" : "=r" (chiprev));
+	asm("mrc p15, 0, %0, c0, c0" : "=r" (chiprev));
 	if ((chiprev & CP15R0_VENDOR_MASK) != CP15R0_XSCALE_VALUE) {
 		pr_err("%s: not XScale!\n", driver_name);
 		return -ENODEV;
-- 
2.29.2




More information about the linux-arm-kernel mailing list