This is a note to let you know that I've just added the patch titled usb: musb: da8xx: fix babble condition handling to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: usb-musb-da8xx-fix-babble-condition-handling.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From bd3486ded7a0c313a6575343e6c2b21d14476645 Mon Sep 17 00:00:00 2001 From: Bin Liu <b-liu@xxxxxx> Date: Tue, 5 Dec 2017 08:45:30 -0600 Subject: usb: musb: da8xx: fix babble condition handling From: Bin Liu <b-liu@xxxxxx> commit bd3486ded7a0c313a6575343e6c2b21d14476645 upstream. When babble condition happens, the musb controller might automatically turns off VBUS. On DA8xx platform, the controller generates drvvbus interrupt for turning off VBUS along with the babble interrupt. In this case, we should handle the babble interrupt first and recover from the babble condition. This change ignores the drvvbus interrupt if babble interrupt is also generated at the same time, so the babble recovery routine works properly. Signed-off-by: Bin Liu <b-liu@xxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/musb/da8xx.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) --- a/drivers/usb/musb/da8xx.c +++ b/drivers/usb/musb/da8xx.c @@ -350,7 +350,15 @@ static irqreturn_t da8xx_musb_interrupt( musb->xceiv->otg->state = OTG_STATE_A_WAIT_VRISE; portstate(musb->port1_status |= USB_PORT_STAT_POWER); del_timer(&otg_workaround); - } else { + } else if (!(musb->int_usb & MUSB_INTR_BABBLE)){ + /* + * When babble condition happens, drvvbus interrupt + * is also generated. Ignore this drvvbus interrupt + * and let babble interrupt handler recovers the + * controller; otherwise, the host-mode flag is lost + * due to the MUSB_DEV_MODE() call below and babble + * recovery logic will not called. + */ musb->is_active = 0; MUSB_DEV_MODE(musb); otg->default_a = 0; Patches currently in stable-queue which might be from b-liu@xxxxxx are queue-4.4/usb-musb-da8xx-fix-babble-condition-handling.patch