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>

diff --git a/drivers/usb/musb/omap2430.c b/drivers/usb/musb/omap2430.c
index 5c93226e0e20a5971654a7c802e58afb75f20806..920862c3fc64432387d7c410f33967ab2c948df4 100644 (file)
--- 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;
 }