From: Sebastian Andrzej Siewior Date: Mon, 27 Oct 2014 18:06:19 +0000 (+0100) Subject: usb: musb: try a race-free wakeup X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=baadd52f0aa7a100192661132299f13e763932df;p=openwrt%2Fstaging%2Fblogic.git usb: musb: try a race-free wakeup Attaching a keyboard, using it as a wakeup via |for f in $(find /sys/devices/ocp.3/47400000.usb -name wakeup) |do | echo enabled > $f |done going into standby | echo standby > /sys/power/state and now a wake up by a pressing a key. What happens is that the system wakes up but the USB device is dead. The USB stack tries to send a few control URBs but nothing comes back. Eventually it gaves up and the device remains dead: |[ 632.559678] PM: Wakeup source USB1_PHY |[ 632.581074] PM: noirq resume of devices complete after 21.261 msecs |[ 632.607521] PM: early resume of devices complete after 10.360 msecs |[ 632.616854] net eth2: initializing cpsw version 1.12 (0) |[ 632.704126] net eth2: phy found : id is : 0x4dd074 |[ 636.704048] libphy: 4a101000.mdio:00 - Link is Up - 1000/Full |[ 638.444620] usb 1-1: reset low-speed USB device number 2 using musb-hdrc |[ 653.713435] usb 1-1: device descriptor read/64, error -110 |[ 669.093435] usb 1-1: device descriptor read/64, error -110 |[ 669.473424] usb 1-1: reset low-speed USB device number 2 using musb-hdrc |[ 684.743436] usb 1-1: device descriptor read/64, error -110 |[ 690.065097] PM: resume of devices complete after 57450.744 msecs |[ 690.076601] PM: Finishing wakeup. |[ 690.076627] Restarting tasks ... It seems that since we got woken up via MUSB_INTR_RESUME the musb_host_finish_resume() callback is executed before the resume-callbacks of the PHY and glue layer are invoked. If I delay it until the glue layer resumed then I don't see this problem. I also move musb_host_resume_root_hub() into that callback since I don't see any reason in doing anything resume-link if there are still pieces not restored. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Felipe Balbi --- diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c index 4966a166929a..3345c945262f 100644 --- a/drivers/usb/musb/musb_core.c +++ b/drivers/usb/musb/musb_core.c @@ -478,13 +478,10 @@ static irqreturn_t musb_stage0_irq(struct musb *musb, u8 int_usb, | MUSB_PORT_STAT_RESUME; musb->rh_timer = jiffies + msecs_to_jiffies(20); - schedule_delayed_work( - &musb->finish_resume_work, - msecs_to_jiffies(20)); + musb->need_finish_resume = 1; musb->xceiv->otg->state = OTG_STATE_A_HOST; musb->is_active = 1; - musb_host_resume_root_hub(musb); break; case OTG_STATE_B_WAIT_ACON: musb->xceiv->otg->state = OTG_STATE_B_PERIPHERAL; @@ -2319,6 +2316,11 @@ static int musb_resume(struct device *dev) mask = MUSB_DEVCTL_BDEVICE | MUSB_DEVCTL_FSDEV | MUSB_DEVCTL_LSDEV; if ((devctl & mask) != (musb->context.devctl & mask)) musb->port1_status = 0; + if (musb->need_finish_resume) { + musb->need_finish_resume = 0; + schedule_delayed_work(&musb->finish_resume_work, + msecs_to_jiffies(20)); + } return 0; } diff --git a/drivers/usb/musb/musb_core.h b/drivers/usb/musb/musb_core.h index 414e57a984bb..803a997e56d2 100644 --- a/drivers/usb/musb/musb_core.h +++ b/drivers/usb/musb/musb_core.h @@ -390,6 +390,7 @@ struct musb { /* is_suspended means USB B_PERIPHERAL suspend */ unsigned is_suspended:1; + unsigned need_finish_resume :1; /* may_wakeup means remote wakeup is enabled */ unsigned may_wakeup:1; diff --git a/drivers/usb/musb/musb_virthub.c b/drivers/usb/musb/musb_virthub.c index a133bd8c5dc7..b072420e44f5 100644 --- a/drivers/usb/musb/musb_virthub.c +++ b/drivers/usb/musb/musb_virthub.c @@ -72,6 +72,7 @@ void musb_host_finish_resume(struct work_struct *work) musb->xceiv->otg->state = OTG_STATE_A_HOST; spin_unlock_irqrestore(&musb->lock, flags); + musb_host_resume_root_hub(musb); } void musb_port_suspend(struct musb *musb, bool do_suspend)