From ce3ab6503ebaba976405858616d7f6094e364973 Mon Sep 17 00:00:00 2001
From: Tony Lindgren <tony@atomide.com>
Date: Wed, 15 Jan 2020 07:25:27 -0600
Subject: [PATCH] usb: musb: omap2430: Wait on enable to avoid babble

We can get babble interrupt if we attempt to switch to USB host mode too
soon after enabling musb. Let's fix the issue by waiting a bit in
runtime_resume.

Cc: Jacopo Mondi <jacopo@jmondi.org>
Cc: Marcel Partap <mpartap@gmx.net>
Cc: Merlijn Wajer <merlijn@wizzup.org>
Cc: Michael Scott <hashcode0f@gmail.com>
Cc: NeKit <nekit1000@gmail.com>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Sebastian Reichel <sre@kernel.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Bin Liu <b-liu@ti.com>
Link: https://lore.kernel.org/r/20200115132547.364-6-b-liu@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/musb/omap2430.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/usb/musb/omap2430.c b/drivers/usb/musb/omap2430.c
index 5c93226e0e20..920862c3fc64 100644
--- a/drivers/usb/musb/omap2430.c
+++ b/drivers/usb/musb/omap2430.c
@@ -550,6 +550,9 @@ static int omap2430_runtime_resume(struct device *dev)
 	musb_writel(musb->mregs, OTG_INTERFSEL,
 		    musb->context.otg_interfsel);
 
+	/* Wait for musb to get oriented. Otherwise we can get babble */
+	usleep_range(200000, 250000);
+
 	return 0;
 }