Re: [PATCH v4 9/9] usb: dwc3: core: don't break during suspend/resume while we're dual-role

From: Felipe Balbi <balbi@ti.com>
To: Roger Quadros <rogerq@ti.com>
Cc: <balbi@ti.com>, <tony@atomide.com>, <Joao.Pinto@synopsys.com>,
	<sergei.shtylyov@cogentembedded.com>, <peter.chen@freescale.com>,
	<jun.li@freescale.com>, <linux-usb@vger.kernel.org>,
	<linux-kernel@vger.kernel.org>, <linux-omap@vger.kernel.org>
Subject: Re: [PATCH v4 9/9] usb: dwc3: core: don't break during suspend/resume while we're dual-role
Date: Wed, 2 Sep 2015 09:48:12 -0500	[thread overview]
Message-ID: <20150902144812.GJ8299@saruman.tx.rr.com> (raw)
In-Reply-To: <1441203864-15786-10-git-send-email-rogerq@ti.com>

[-- Attachment #1: Type: text/plain, Size: 2527 bytes --]

On Wed, Sep 02, 2015 at 05:24:24PM +0300, Roger Quadros wrote:
> We can't rely just on dr_mode to decide if we're in host or gadget
> mode when we're configured as otg/dual-role. So while dr_mode is
> OTG, we find out from  the otg state machine if we're in host
> or gadget mode and take the necessary actions during suspend/resume.
> 
> Also make sure that we disable OTG irq and events during system suspend
> so that we don't lockup the system during system suspend/resume.
> 
> Signed-off-by: Roger Quadros <rogerq@ti.com>
> ---
>  drivers/usb/dwc3/core.c | 27 +++++++++------------------
>  1 file changed, 9 insertions(+), 18 deletions(-)
> 
> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index 654aebf..25891e3 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -1455,18 +1455,15 @@ static int dwc3_suspend(struct device *dev)
>  		dwc->octl = dwc3_readl(dwc->regs, DWC3_OCTL);
>  		dwc->oevt = dwc3_readl(dwc->regs, DWC3_OEVT);
>  		dwc->oevten = dwc3_readl(dwc->regs, DWC3_OEVTEN);
> +		dwc3_writel(dwc->regs, DWC3_OEVTEN, 0);
> +		disable_irq(dwc->otg_irq);

you don't need disable_irq() here. In fact, it causes problems since
you're calling it with IRQs disabled.

>  	}
>  
> -	switch (dwc->dr_mode) {
> -	case USB_DR_MODE_PERIPHERAL:
> -	case USB_DR_MODE_OTG:
> +	if (dwc->dr_mode == USB_DR_MODE_PERIPHERAL ||
> +	    ((dwc->dr_mode == USB_DR_MODE_OTG) && (dwc->fsm->protocol == PROTO_GADGET)))
>  		dwc3_gadget_suspend(dwc);
> -		/* FALLTHROUGH */
> -	case USB_DR_MODE_HOST:
> -	default:
> -		dwc3_event_buffers_cleanup(dwc);
> -		break;
> -	}
> +
> +	dwc3_event_buffers_cleanup(dwc);
>  
>  	dwc->gctl = dwc3_readl(dwc->regs, DWC3_GCTL);
>  	spin_unlock_irqrestore(&dwc->lock, flags);
> @@ -1506,18 +1503,12 @@ static int dwc3_resume(struct device *dev)
>  		dwc3_writel(dwc->regs, DWC3_OCTL, dwc->octl);
>  		dwc3_writel(dwc->regs, DWC3_OEVT, dwc->oevt);
>  		dwc3_writel(dwc->regs, DWC3_OEVTEN, dwc->oevten);
> +		enable_irq(dwc->otg_irq);
>  	}
>  
> -	switch (dwc->dr_mode) {
> -	case USB_DR_MODE_PERIPHERAL:
> -	case USB_DR_MODE_OTG:
> +	if (dwc->dr_mode == USB_DR_MODE_PERIPHERAL ||
> +	    ((dwc->dr_mode == USB_DR_MODE_OTG) && (dwc->fsm->protocol == PROTO_GADGET)))
>  		dwc3_gadget_resume(dwc);
> -		/* FALLTHROUGH */
> -	case USB_DR_MODE_HOST:
> -	default:
> -		/* do nothing */
> -		break;
> -	}
>  
>  	spin_unlock_irqrestore(&dwc->lock, flags);
>  
> -- 
> 2.1.4
> 

-- 
balbi

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 819 bytes --]