On start-up, we can get a spurious session request interrupt with nothing connected. After that the devctl session bit will silently clear, but the musb hardware is never idled until a cable is plugged in, or the glue layer module is reloaded. Let's just check the session bit again in 3 seconds in peripheral mode to catch the issue. Signed-off-by: Tony Lindgren <tony@xxxxxxxxxxx> --- drivers/usb/musb/musb_core.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c --- a/drivers/usb/musb/musb_core.c +++ b/drivers/usb/musb/musb_core.c @@ -2055,6 +2055,15 @@ static void musb_pm_runtime_check_session(struct musb *musb) dev_err(musb->controller, "Could not enable: %i\n", error); musb->quirk_retries = 3; + + /* + * We can get a spurious MUSB_INTR_SESSREQ interrupt on start-up + * in B-peripheral mode with nothing connected and the session + * bit clears silently. Check status again in 3 seconds. + */ + if (devctl & MUSB_DEVCTL_BDEVICE) + schedule_delayed_work(&musb->irq_work, + msecs_to_jiffies(3000)); } else { musb_dbg(musb, "Allow PM with no session: %02x", devctl); pm_runtime_mark_last_busy(musb->controller); -- 2.31.1