From 971b750d31079e13c18e4ac335804401cfeb189d Mon Sep 17 00:00:00 2001
From: Stefan Wahren <stefan.wahren@i2se.com>
Date: Fri, 4 May 2018 20:09:05 +0200
Subject: [PATCH] usb: dwc2: debugfs: Don't touch RX FIFO during register dump
Git-commit: 971b750d31079e13c18e4ac335804401cfeb189d
Patch-mainline: v4.18-rc1
References: bsc#1051510
Dumping the registers via debugfs makes USB on Raspberry Pi completely
unusable. The read of register GRXSTSP ("Receive Status Read and Pop
Register") is responsible for this behaviour, because it pops the RX FIFO.
So avoid this by omitting the relevant register.
Cc: Mian Yousaf Kaukab <yousaf.kaukab@intel.com>
Fixes: 563cf017c443 ("usb: dwc2: debugfs: add support for complete register dump")
Acked-by: Minas Harutyunyan <hminas@synopsys.com>
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/usb/dwc2/debugfs.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/usb/dwc2/debugfs.c b/drivers/usb/dwc2/debugfs.c
index 5897333600a7..a21f89354434 100644
--- a/drivers/usb/dwc2/debugfs.c
+++ b/drivers/usb/dwc2/debugfs.c
@@ -368,7 +368,7 @@ static const struct debugfs_reg32 dwc2_regs[] = {
dump_register(GINTSTS),
dump_register(GINTMSK),
dump_register(GRXSTSR),
- dump_register(GRXSTSP),
+ /* Omit GRXSTSP */
dump_register(GRXFSIZ),
dump_register(GNPTXFSIZ),
dump_register(GNPTXSTS),
--
2.18.0