From: "Rafael J. Wysocki" <rjw@sisk.pl>
To: Huang Ying <ying.huang@intel.com>
Subject: Re: [BUGFIX 1/4] PCI/PM: enable D3/D3cold by default for most devices
Date: Sat, 4 Aug 2012 23:46:47 +0200
User-Agent: KMail/1.13.6 (Linux/3.5.0+; KDE/4.6.0; x86_64; ; )
Cc: Bjorn Helgaas <bhelgaas@google.com>, linux-kernel@vger.kernel.org,
        linux-pci@vger.kernel.org, linux-pm@vger.kernel.org
References: <1343975435-25469-1-git-send-email-ying.huang@intel.com> <1343975435-25469-2-git-send-email-ying.huang@intel.com>
In-Reply-To: <1343975435-25469-2-git-send-email-ying.huang@intel.com>
MIME-Version: 1.0
Content-Type: Text/Plain;
  charset="iso-8859-2"
Content-Transfer-Encoding: 7bit
Message-Id: <201208042346.47702.rjw@sisk.pl>
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 2139
Lines: 62

On Friday, August 03, 2012, Huang Ying wrote:
> This patch fixes the following bug:
> 
> http://marc.info/?l=linux-usb&m=134318961120825&w=2
> 
> Originally, device lower power states include D1, D2, D3.  After that,
> D3 is further divided into D3hot and D3cold.  To support both scenario
> safely, original D3 is mapped to D3cold.
> 
> When adding D3cold support, because worry about some device may have
> broken D3cold support, D3cold is disabled by default.  This disable D3
> on original platform too.  But some original platform may only have
> working D3, but no working D1, D2.  The root cause of the above bug is
> it too.
> 
> To deal with this, this patch enables D3/D3cold by default for most
> devices.  This restores the original behavior.  For some devices that
> suspected to have broken D3cold support, such as PCIe port, D3cold is
> disabled by default.
> 
> Reported-by: Bjorn Mork <bjorn@mork.no>
> Signed-off-by: Huang Ying <ying.huang@intel.com>

Reviewed-by: Rafael J. Wysocki <rjw@sisk.pl>

> ---
>  drivers/pci/pci.c              |    1 +
>  drivers/pci/pcie/portdrv_pci.c |    5 +++++
>  2 files changed, 6 insertions(+)
> 
> --- a/drivers/pci/pci.c
> +++ b/drivers/pci/pci.c
> @@ -1941,6 +1941,7 @@ void pci_pm_init(struct pci_dev *dev)
>  	dev->pm_cap = pm;
>  	dev->d3_delay = PCI_PM_D3_WAIT;
>  	dev->d3cold_delay = PCI_PM_D3COLD_WAIT;
> +	dev->d3cold_allowed = true;
>  
>  	dev->d1_support = false;
>  	dev->d2_support = false;
> --- a/drivers/pci/pcie/portdrv_pci.c
> +++ b/drivers/pci/pcie/portdrv_pci.c
> @@ -200,6 +200,11 @@ static int __devinit pcie_portdrv_probe(
>  		return status;
>  
>  	pci_save_state(dev);
> +	/*
> +	 * D3cold may not work properly on some PCIe port, so disable
> +	 * it by default.
> +	 */
> +	dev->d3cold_allowed = false;
>  	if (!pci_match_id(port_runtime_pm_black_list, dev))
>  		pm_runtime_put_noidle(&dev->dev);
>  
> 
> 

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/