From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751066AbcDKLjc (ORCPT ); Mon, 11 Apr 2016 07:39:32 -0400 Received: from comal.ext.ti.com ([198.47.26.152]:40710 "EHLO comal.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751175AbcDKLja (ORCPT ); Mon, 11 Apr 2016 07:39:30 -0400 Subject: Re: [PATCH v2] extcon: usb-gpio: Don't miss event during suspend/resume To: Chanwoo Choi , Grygorii Strashko , References: <1459951299-20578-1-git-send-email-rogerq@ti.com> <57075F23.8080703@ti.com> <570AF062.5000609@samsung.com> <570B6248.6080905@ti.com> <570B8686.3050306@samsung.com> CC: From: Roger Quadros Message-ID: <570B8CE7.3060605@ti.com> Date: Mon, 11 Apr 2016 14:39:19 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 In-Reply-To: <570B8686.3050306@samsung.com> Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Chanwoo, On 11/04/16 14:12, Chanwoo Choi wrote: > On 2016년 04월 11일 17:37, Grygorii Strashko wrote: >> On 04/11/2016 03:31 AM, Chanwoo Choi wrote: >>> Hi Roger, >>> >>> On 2016년 04월 08일 16:34, Roger Quadros wrote: >>>> Pin state might have changed during suspend/resume while >>>> our interrupts were disabled and if device doesn't support wakeup. >>>> >>>> Scan for change during resume for such case. >>>> >>>> Signed-off-by: Roger Quadros >>>> --- >>>> v2: >>>> - only check for state change during resume if device wakeup is not supported >>>> >>>> drivers/extcon/extcon-usb-gpio.c | 2 ++ >>>> 1 file changed, 2 insertions(+) >>>> >>>> diff --git a/drivers/extcon/extcon-usb-gpio.c b/drivers/extcon/extcon-usb-gpio.c >>>> index bc61d11..118f8ab 100644 >>>> --- a/drivers/extcon/extcon-usb-gpio.c >>>> +++ b/drivers/extcon/extcon-usb-gpio.c >>>> @@ -185,6 +185,8 @@ static int usb_extcon_resume(struct device *dev) >>>> int ret = 0; >>>> >>>> enable_irq(info->id_irq); >>>> + if (!device_may_wakeup(dev)) >>>> + usb_extcon_detect_cable(&info->wq_detcable.work); >>> >>> The device_may_wakeup() check the following two states: >>> - dev->power.can_wakeup - device_init_wakeup() function set the this field. >>> - dev->power.wakeup - device_wakeup_enable() function set the this field. >>> >>> The probe function of extcon-usb-gpio.c always call the 'device_init_wakeup(dev,true). >>> But, anywhere in extcon-usb-gpio.c don't handle the device_wakeup_enable() for dev->power.wakeup. >> >> >> device_init_wakeup() >> |-> device_wakeup_enable() >> >>> >>> In the extcon-usb-gpio.c, device_may_wakeup(dev) return always 'false'. >>> If you use the only device_may_wakeup(), >>> device_may_wakeup() is not able to check whether interrupt is wakeup source or not. >>> >> >> This check is correct and it also will take into account wake up settings changes >> which can be made through sysfs: /sys/.../devX/power/wakeup >> > > To Grygorii, > > You're right. I was mistaken. Again, I analyzed the sequence about wakeup. > Thanks for your reply. > > 1. Register device as wakeup_source. > device_init_wakeup(dev, true) on probe() > device_wakeup_enable(dev) > device_source_register(const char *name) > struct wakeup_source *ws; > ws = wakeup_source_create(name) > if (ws) > wakeup_source_add(ws); > ... > list_add_rcu(&ws->entry, &wakeup_sources); > ... > return ws; > > > 2. Register the interrupt as wake_irq > dev_pm_set_wake_irq(struct device *dev, int irq) on probe() > struct wake_irq *wirq; > wirq->dev = dev; > wirq->irq = irq; > dev_pm_attach_wake_irq(dev, irq, wirq); > device_wakeup_attach_irq(*dev, *wakeirq) > struct wakeup_source *ws; > ws = dev->power.wakeup; > ws->wakeirq = wakeirq; > > > 3. Enable irq wake if device is already registed to wakeup_sources. > dpm_suspend_noirq() > device_wakeup_arm_wake_irqs() > list_for_each_entry_rcu(ws, &wakeup_sources, entry) { > if (ws->wakeirq) > dev_pm_arm_wake_irq(sw->wakeirq); > if (device_may_wakeup(wirq->dev)) > enable_irq_wake(wirq->irq); > > > To Roger, > > How about using the queue_delayed_work() instead of direct call function? > Because the spent time of wakeup from suspend state should be fast. > So, I think that you better to use the queue_delayed_work(). > > diff --git a/drivers/extcon/extcon-usb-gpio.c b/drivers/extcon/extcon-usb-gpio.c > index 118f8ab3be73..f6cbdfe31519 100644 > --- a/drivers/extcon/extcon-usb-gpio.c > +++ b/drivers/extcon/extcon-usb-gpio.c > @@ -186,7 +186,9 @@ static int usb_extcon_resume(struct device *dev) > > enable_irq(info->id_irq); > if (!device_may_wakeup(dev)) > - usb_extcon_detect_cable(&info->wq_detcable.work); > + queue_delayed_work(system_power_efficient_wq, > + &info->wq_detcable, > + info->debounce_jiffies); Why not to just use queue_work() instead of queue_delayed_work() as don't need to debounce the input? cheers, -roger > > return ret; > }