Re: [PATCH] usb: host: ehci-msm: Conditionally call ehci suspend/resume

Path	csiph.com!news.mixmin.net!aioe.org!bofh.it!news.nic.it!robomod
From	Alan Stern <stern@rowland.harvard.edu>
Newsgroups	linux.kernel
Subject	Re: [PATCH] usb: host: ehci-msm: Conditionally call ehci suspend/resume
Date	Sat, 21 May 2016 16:40:02 +0200
Message-ID	<rBgem-4Gi-15@gated-at.bofh.it> (permalink)
References	<rB0jg-2Q7-5@gated-at.bofh.it>
X-X-Sender	stern@netrider.rowland.org
MIME-Version	1.0
Content-Type	TEXT/PLAIN; charset=US-ASCII
Sender	robomod@news.nic.it
List-ID	<linux-kernel.vger.kernel.org>
X-Mailing-List	linux-kernel@vger.kernel.org
Approved	robomod@news.nic.it
Lines	52
Organization	linux.* mail to news gateway
X-Original-Cc	Greg Kroah-Hartman <gregkh@linuxfoundation.org>, <linux-usb@vger.kernel.org>, <linux-kernel@vger.kernel.org>, <linux-arm-msm@vger.kernel.org>, <srinivas.kandagatla@linaro.org>
X-Original-Date	Sat, 21 May 2016 10:30:58 -0400 (EDT)
X-Original-Message-ID	<Pine.LNX.4.44L0.1605211030460.31016-100000@netrider.rowland.org>
X-Original-References	<1463780107-12792-1-git-send-email-andy.gross@linaro.org>
X-Original-Sender	linux-kernel-owner@vger.kernel.org
Xref	csiph.com linux.kernel:1404849

Show key headers only | View raw

On Fri, 20 May 2016, Andy Gross wrote:

> This patch fixes a suspend/resume issue where the driver is blindly
> calling ehci_suspend/resume functions when the ehci hasn't been setup.
> This results in a crash during suspend/resume operations.
> 
> Signed-off-by: Andy Gross <andy.gross@linaro.org>
> ---
>  drivers/usb/host/ehci-msm.c | 14 ++++++++++++--
>  1 file changed, 12 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/usb/host/ehci-msm.c b/drivers/usb/host/ehci-msm.c
> index 3e226ef..9996a60 100644
> --- a/drivers/usb/host/ehci-msm.c
> +++ b/drivers/usb/host/ehci-msm.c
> @@ -179,22 +179,32 @@ static int ehci_msm_remove(struct platform_device *pdev)
>  static int ehci_msm_pm_suspend(struct device *dev)
>  {
>  	struct usb_hcd *hcd = dev_get_drvdata(dev);
> +	struct ehci_hcd *ehci = hcd_to_ehci(hcd);
>  	bool do_wakeup = device_may_wakeup(dev);
>  
>  	dev_dbg(dev, "ehci-msm PM suspend\n");
>  
> -	return ehci_suspend(hcd, do_wakeup);
> +	/* Only call ehci_suspend if ehci_setup has been done */
> +	if (ehci->sbrn)
> +		return ehci_suspend(hcd, do_wakeup);
> +
> +	return 0;
>  }
>  
>  static int ehci_msm_pm_resume(struct device *dev)
>  {
>  	struct usb_hcd *hcd = dev_get_drvdata(dev);
> +	struct ehci_hcd *ehci = hcd_to_ehci(hcd);
>  
>  	dev_dbg(dev, "ehci-msm PM resume\n");
> -	ehci_resume(hcd, false);
> +
> +	/* Only call ehci_resume if ehci_setup has been done */
> +	if (ehci->sbrn)
> +		ehci_resume(hcd, false);
>  
>  	return 0;
>  }
> +
>  #else
>  #define ehci_msm_pm_suspend	NULL
>  #define ehci_msm_pm_resume	NULL

Acked-by: Alan Stern <stern@rowland.harvard.edu>

Thread

[PATCH] usb: host: ehci-msm: Conditionally call ehci suspend/resume Andy Gross <andy.gross@linaro.org> - 2016-05-20 23:40 +0200
  Re: [PATCH] usb: host: ehci-msm: Conditionally call ehci suspend/resume Alan Stern <stern@rowland.harvard.edu> - 2016-05-21 16:40 +0200
  Re: [PATCH] usb: host: ehci-msm: Conditionally call ehci suspend/resume Pramod Gurav <pramod.gurav@linaro.org> - 2016-05-26 09:00 +0200

csiph-web