Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Content-Type: text/plain;
        charset=us-ascii
Mime-Version: 1.0 (Mac OS X Mail 13.4 \(3608.120.23.2.4\))
Subject: Re: [PATCH v3] xhci: Prevent runtime suspend on Etron EJ168
From:   Kai-Heng Feng <kai.heng.feng@canonical.com>
In-Reply-To: <0F26EE78-D4F4-4CCB-892B-999E203BF515@canonical.com>
Date:   Mon, 28 Sep 2020 17:10:22 +0800
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        "open list:USB XHCI DRIVER" <linux-usb@vger.kernel.org>,
        open list <linux-kernel@vger.kernel.org>
Content-Transfer-Encoding: 8BIT
Message-Id: <14291E1B-6580-4C69-9EF8-3B30BC78B8D0@canonical.com>
References: <20200504171642.26947-1-kai.heng.feng@canonical.com>
 <0F26EE78-D4F4-4CCB-892B-999E203BF515@canonical.com>
To:     Mathias Nyman <mathias.nyman@intel.com>
Precedence: bulk


> On Jun 8, 2020, at 11:56, Kai-Heng Feng <kai.heng.feng@canonical.com> wrote:
> 
> 
> 
>> On May 5, 2020, at 01:16, Kai-Heng Feng <kai.heng.feng@canonical.com> wrote:
>> 
>> Etron EJ168 USB 3.0 Host Controller stops working after S3, if it was
>> runtime suspended previously:
>> [  370.080359] pci 0000:02:00.0: can't change power state from D3cold to D0 (config space inaccessible)
>> [  370.080477] xhci_hcd 0000:04:00.0: can't change power state from D3cold to D0 (config space inaccessible)
>> [  370.080532] pcieport 0000:00:1c.0: DPC: containment event, status:0x1f05 source:0x0200
>> [  370.080533] pcieport 0000:00:1c.0: DPC: ERR_FATAL detected
>> [  370.080536] xhci_hcd 0000:04:00.0: can't change power state from D3hot to D0 (config space inaccessible)
>> [  370.080552] xhci_hcd 0000:04:00.0: AER: can't recover (no error_detected callback)
>> [  370.080566] usb usb3: root hub lost power or was reset
>> [  370.080566] usb usb4: root hub lost power or was reset
>> [  370.080572] xhci_hcd 0000:04:00.0: Host halt failed, -19
>> [  370.080574] xhci_hcd 0000:04:00.0: Host not accessible, reset failed.
>> [  370.080575] xhci_hcd 0000:04:00.0: PCI post-resume error -19!
>> [  370.080586] xhci_hcd 0000:04:00.0: HC died; cleaning up
>> 
>> This can be fixed by not runtime suspend the controller at all.
>> 
>> So disable runtime suspend for EJ168 xHCI device.
>> 
>> Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
> 
> A gentle ping...

Another gentle ping...

> 
>> ---
>> v3:
>> - Balance rpm refcount in remove callback.
>> 
>> v2:
>> - Use a new quirk to avoid changing existing behavior.
>> 
>> drivers/usb/host/xhci-pci.c | 7 ++++++-
>> drivers/usb/host/xhci.h     | 1 +
>> 2 files changed, 7 insertions(+), 1 deletion(-)
>> 
>> diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
>> index 766b74723e64..67b4b433a93e 100644
>> --- a/drivers/usb/host/xhci-pci.c
>> +++ b/drivers/usb/host/xhci-pci.c
>> @@ -227,6 +227,7 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci)
>> 		xhci->quirks |= XHCI_RESET_ON_RESUME;
>> 		xhci->quirks |= XHCI_TRUST_TX_LENGTH;
>> 		xhci->quirks |= XHCI_BROKEN_STREAMS;
>> +		xhci->quirks |= XHCI_DISABLE_RUNTIME_SUSPEND;
>> 	}
>> 	if (pdev->vendor == PCI_VENDOR_ID_RENESAS &&
>> 	    pdev->device == 0x0014) {
>> @@ -371,7 +372,8 @@ static int xhci_pci_probe(struct pci_dev *dev, const struct pci_device_id *id)
>> 		xhci->shared_hcd->can_do_streams = 1;
>> 
>> 	/* USB-2 and USB-3 roothubs initialized, allow runtime pm suspend */
>> -	pm_runtime_put_noidle(&dev->dev);
>> +	if (!(xhci->quirks & XHCI_DISABLE_RUNTIME_SUSPEND))
>> +		pm_runtime_put_noidle(&dev->dev);
>> 
>> 	if (xhci->quirks & XHCI_DEFAULT_PM_RUNTIME_ALLOW)
>> 		pm_runtime_allow(&dev->dev);
>> @@ -397,6 +399,9 @@ static void xhci_pci_remove(struct pci_dev *dev)
>> 	if (xhci->quirks & XHCI_DEFAULT_PM_RUNTIME_ALLOW)
>> 		pm_runtime_forbid(&dev->dev);
>> 
>> +	if (!(xhci->quirks & XHCI_DISABLE_RUNTIME_SUSPEND))
>> +		pm_runtime_get_noresume(&dev->dev);
>> +
>> 	if (xhci->shared_hcd) {
>> 		usb_remove_hcd(xhci->shared_hcd);
>> 		usb_put_hcd(xhci->shared_hcd);
>> diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
>> index 86cfefdd6632..d9c209a10d3f 100644
>> --- a/drivers/usb/host/xhci.h
>> +++ b/drivers/usb/host/xhci.h
>> @@ -1873,6 +1873,7 @@ struct xhci_hcd {
>> #define XHCI_DEFAULT_PM_RUNTIME_ALLOW	BIT_ULL(33)
>> #define XHCI_RESET_PLL_ON_DISCONNECT	BIT_ULL(34)
>> #define XHCI_SNPS_BROKEN_SUSPEND    BIT_ULL(35)
>> +#define XHCI_DISABLE_RUNTIME_SUSPEND    BIT_ULL(36)
>> 
>> 	unsigned int		num_active_eps;
>> 	unsigned int		limit_active_eps;
>> -- 
>> 2.17.1
>> 
>