[PATCH 0/3] Rework "xhci: clear root port wake on bits if controller isn't wake-up capable"

[PATCH 0/3] Rework "xhci: clear root port wake on bits if controller isn't wake-up capable"

[Lu Baolu]

This serie of patch reworks commit ff8cbf250b448aac35589f6075082c3fcad8a8fe.
This has been discussed at http://www.spinics.net/lists/linux-usb/msg114986.html
It also includes a patch to fix a comment in drivers/usb/host/xhci.h.

Lu Baolu (3):
  usb: xhci: Revert "xhci: clear root port wake on bits if controller
    isn't wake-up capable"
  usb: xhci: This reworks ff8cbf250b448aac35589f6075082c3fcad8a8fe
  usb: xhci: fix comment for PORT_DEV_REMOVE

 drivers/usb/host/xhci-hub.c |  5 +----
 drivers/usb/host/xhci-pci.c | 42 ++++++++++++++++++++++++++++++++++++++++++
 drivers/usb/host/xhci.h     |  8 +++++++-
 3 files changed, 50 insertions(+), 5 deletions(-)

-- 
1.9.1

[PATCH 1/3] usb: xhci: Revert "xhci: clear root port wake on bits if controller isn't wake-up capable"

[Lu Baolu]

This reverts commit ff8cbf250b448aac35589f6075082c3fcad8a8fe.

Commit ff8cbf250b448aac35589f6075082c3fcad8a8fe triggers the bug logged at

https://bugzilla.kernel.org/show_bug.cgi?id=85701

Reported-by: Dmitry Nezhevenko <dion@inhex.net>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
---
 drivers/usb/host/xhci-hub.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c
index 696160d..388cfd8 100644
--- a/drivers/usb/host/xhci-hub.c
+++ b/drivers/usb/host/xhci-hub.c
@@ -22,7 +22,6 @@
 
 
 #include <linux/slab.h>
-#include <linux/device.h>
 #include <asm/unaligned.h>
 
 #include "xhci.h"
@@ -1149,9 +1148,7 @@ int xhci_bus_suspend(struct usb_hcd *hcd)
 		 * including the USB 3.0 roothub, but only if CONFIG_PM_RUNTIME
 		 * is enabled, so also enable remote wake here.
 		 */
-		if (hcd->self.root_hub->do_remote_wakeup
-				&& device_may_wakeup(hcd->self.controller)) {
-
+		if (hcd->self.root_hub->do_remote_wakeup) {
 			if (t1 & PORT_CONNECT) {
 				t2 |= PORT_WKOC_E | PORT_WKDISC_E;
 				t2 &= ~PORT_WKCONN_E;
-- 
1.9.1

[PATCH 2/3] usb: xhci: This reworks ff8cbf250b448aac35589f6075082c3fcad8a8fe

[Lu Baolu]

xhci: clear root port wake on bits if controller isn't wake-up capable

When xHCI PCI host is suspended, if do_wakeup is false in xhci_pci_suspend,
xhci_pci_suspend needs to clear all root port wake on bits. Otherwise some Intel
platforms may get a spurious wakeup, even if PCI PME# is disabled.

Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
---
 drivers/usb/host/xhci-pci.c | 42 ++++++++++++++++++++++++++++++++++++++++++
 drivers/usb/host/xhci.h     |  6 ++++++
 2 files changed, 48 insertions(+)

diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index 280dde9..3e7441a 100644
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -27,6 +27,8 @@
 #include "xhci.h"
 #include "xhci-trace.h"
 
+#define	PORT_WAKE_BITS	(PORT_WKOC_E | PORT_WKDISC_E | PORT_WKCONN_E)
+
 /* Device for a quirk */
 #define PCI_VENDOR_ID_FRESCO_LOGIC	0x1b73
 #define PCI_DEVICE_ID_FRESCO_LOGIC_PDK	0x1000
@@ -126,6 +128,7 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci)
 		 */
 		xhci->quirks |= XHCI_SPURIOUS_REBOOT;
 		xhci->quirks |= XHCI_AVOID_BEI;
+		xhci->quirks |= XHCI_DISABLE_PORT_WOB;
 	}
 	if (pdev->vendor == PCI_VENDOR_ID_INTEL &&
 	    (pdev->device == PCI_DEVICE_ID_INTEL_LYNXPOINT_XHCI ||
@@ -279,6 +282,42 @@ static void xhci_pci_remove(struct pci_dev *dev)
 }
 
 #ifdef CONFIG_PM
+static void xhci_disable_port_wake_bits(struct xhci_hcd *xhci)
+{
+	int port_index;
+	__le32 __iomem **port_array;
+	unsigned long flags;
+	u32 t1, t2;
+
+	spin_lock_irqsave(&xhci->lock, flags);
+
+	/* disble usb3 ports Wake bits*/
+	port_index = xhci->num_usb3_ports;
+	port_array = xhci->usb3_ports;
+	while (port_index--) {
+		t1 = readl(port_array[port_index]);
+		t2 = xhci_port_state_to_neutral(t1);
+		t2 &= ~PORT_WAKE_BITS;
+		t1 = xhci_port_state_to_neutral(t1);
+		if (t1 != t2)
+			writel(t2, port_array[port_index]);
+	}
+
+	/* disble usb2 ports Wake bits*/
+	port_index = xhci->num_usb2_ports;
+	port_array = xhci->usb2_ports;
+	while (port_index--) {
+		t1 = readl(port_array[port_index]);
+		t2 = xhci_port_state_to_neutral(t1);
+		t2 &= ~PORT_WAKE_BITS;
+		t1 = xhci_port_state_to_neutral(t1);
+		if (t1 != t2)
+			writel(t2, port_array[port_index]);
+	}
+
+	spin_unlock_irqrestore(&xhci->lock, flags);
+}
+
 static int xhci_pci_suspend(struct usb_hcd *hcd, bool do_wakeup)
 {
 	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
@@ -291,6 +330,9 @@ static int xhci_pci_suspend(struct usb_hcd *hcd, bool do_wakeup)
 	if (xhci->quirks & XHCI_COMP_MODE_QUIRK)
 		pdev->no_d3cold = true;
 
+	if (xhci->quirks & XHCI_DISABLE_PORT_WOB && !do_wakeup)
+		xhci_disable_port_wake_bits(xhci);
+
 	return xhci_suspend(xhci);
 }
 
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index df76d64..2f6131b 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1560,6 +1560,12 @@ struct xhci_hcd {
 #define XHCI_SPURIOUS_WAKEUP	(1 << 18)
 /* For controllers with a broken beyond repair streams implementation */
 #define XHCI_BROKEN_STREAMS	(1 << 19)
+/*
+ * Some Intel platforms may get a spurious wakeup after entering system
+ * suspend with PCI PME# disabled. Software can workaround this by dis-
+ * abling the wake on bits of all root ports.
+ */
+#define XHCI_DISABLE_PORT_WOB	(1 << 20)
 	unsigned int		num_active_eps;
 	unsigned int		limit_active_eps;
 	/* There are two roothubs to keep track of bus suspend info for */
-- 
1.9.1

[PATCH 3/3] usb: xhci: fix comment for PORT_DEV_REMOVE

[Lu Baolu]

According to xHCI specification, PORT_DEV_REMOVE(bit 30) in PORTSC
true means "Device is non-removable".

Reported-by: Juro Bystricky <jurobystricky@hotmail.com>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
---
 drivers/usb/host/xhci.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index 2f6131b..4e160db 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -358,7 +358,7 @@ struct xhci_op_regs {
 /* wake on over-current (enable) */
 #define PORT_WKOC_E	(1 << 27)
 /* bits 28:29 reserved */
-/* true: device is removable - for USB 3.0 roothub emulation */
+/* true: device is non-removable - for USB 3.0 roothub emulation */
 #define PORT_DEV_REMOVE	(1 << 30)
 /* Initiate a warm port reset - complete when PORT_WRC is '1' */
 #define PORT_WR		(1 << 31)
-- 
1.9.1

Re: [PATCH 2/3] usb: xhci: This reworks ff8cbf250b448aac35589f6075082c3fcad8a8fe

[Alan Stern]

On Fri, 31 Oct 2014, Lu Baolu wrote:

> xhci: clear root port wake on bits if controller isn't wake-up capable
> 
> When xHCI PCI host is suspended, if do_wakeup is false in xhci_pci_suspend,
> xhci_pci_suspend needs to clear all root port wake on bits. Otherwise some Intel
> platforms may get a spurious wakeup, even if PCI PME# is disabled.
> 
> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
> ---
>  drivers/usb/host/xhci-pci.c | 42 ++++++++++++++++++++++++++++++++++++++++++
>  drivers/usb/host/xhci.h     |  6 ++++++
>  2 files changed, 48 insertions(+)
> 
> diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
> index 280dde9..3e7441a 100644
> --- a/drivers/usb/host/xhci-pci.c
> +++ b/drivers/usb/host/xhci-pci.c
> @@ -27,6 +27,8 @@
>  #include "xhci.h"
>  #include "xhci-trace.h"
>  
> +#define	PORT_WAKE_BITS	(PORT_WKOC_E | PORT_WKDISC_E | PORT_WKCONN_E)
> +
>  /* Device for a quirk */
>  #define PCI_VENDOR_ID_FRESCO_LOGIC	0x1b73
>  #define PCI_DEVICE_ID_FRESCO_LOGIC_PDK	0x1000
> @@ -126,6 +128,7 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci)
>  		 */
>  		xhci->quirks |= XHCI_SPURIOUS_REBOOT;
>  		xhci->quirks |= XHCI_AVOID_BEI;
> +		xhci->quirks |= XHCI_DISABLE_PORT_WOB;
>  	}
>  	if (pdev->vendor == PCI_VENDOR_ID_INTEL &&
>  	    (pdev->device == PCI_DEVICE_ID_INTEL_LYNXPOINT_XHCI ||
> @@ -279,6 +282,42 @@ static void xhci_pci_remove(struct pci_dev *dev)
>  }
>  
>  #ifdef CONFIG_PM
> +static void xhci_disable_port_wake_bits(struct xhci_hcd *xhci)
> +{
> +	int port_index;
> +	__le32 __iomem **port_array;
> +	unsigned long flags;
> +	u32 t1, t2;
> +
> +	spin_lock_irqsave(&xhci->lock, flags);
> +
> +	/* disble usb3 ports Wake bits*/
> +	port_index = xhci->num_usb3_ports;
> +	port_array = xhci->usb3_ports;
> +	while (port_index--) {
> +		t1 = readl(port_array[port_index]);
> +		t2 = xhci_port_state_to_neutral(t1);
> +		t2 &= ~PORT_WAKE_BITS;
> +		t1 = xhci_port_state_to_neutral(t1);
> +		if (t1 != t2)
> +			writel(t2, port_array[port_index]);
> +	}
> +
> +	/* disble usb2 ports Wake bits*/
> +	port_index = xhci->num_usb2_ports;
> +	port_array = xhci->usb2_ports;
> +	while (port_index--) {
> +		t1 = readl(port_array[port_index]);
> +		t2 = xhci_port_state_to_neutral(t1);
> +		t2 &= ~PORT_WAKE_BITS;
> +		t1 = xhci_port_state_to_neutral(t1);
> +		if (t1 != t2)
> +			writel(t2, port_array[port_index]);
> +	}
> +
> +	spin_unlock_irqrestore(&xhci->lock, flags);
> +}
> +
>  static int xhci_pci_suspend(struct usb_hcd *hcd, bool do_wakeup)
>  {
>  	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
> @@ -291,6 +330,9 @@ static int xhci_pci_suspend(struct usb_hcd *hcd, bool do_wakeup)
>  	if (xhci->quirks & XHCI_COMP_MODE_QUIRK)
>  		pdev->no_d3cold = true;
>  
> +	if (xhci->quirks & XHCI_DISABLE_PORT_WOB && !do_wakeup)
> +		xhci_disable_port_wake_bits(xhci);
> +
>  	return xhci_suspend(xhci);
>  }

There are two things wrong here.  First, this should not be a quirk.  
The Wake-On bits should be disabled whenever they aren't needed, on 
every controller.

Second, this code (or something like it) belongs in xhci.c or 
xhci-hub.c, not xhci-pci.c.  This is because it should apply to all 
xHCI controllers, not just the PCI-based ones.

(In fact, instead of disabling the Wake-On bits when the controller is 
suspended and do_wakeup is 0, it probably would be better to leave them 
disabled normally and then _enable_ them if do_wakeup is 1.)

Alan Stern

Re: [PATCH 2/3] usb: xhci: This reworks ff8cbf250b448aac35589f6075082c3fcad8a8fe

[Lu, Baolu]

On 10/31/2014 10:28 PM, Alan Stern wrote:
> On Fri, 31 Oct 2014, Lu Baolu wrote:
>
>> xhci: clear root port wake on bits if controller isn't wake-up capable
>>
>> When xHCI PCI host is suspended, if do_wakeup is false in xhci_pci_suspend,
>> xhci_pci_suspend needs to clear all root port wake on bits. Otherwise some Intel
>> platforms may get a spurious wakeup, even if PCI PME# is disabled.
>>
>> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
>> ---
>>   drivers/usb/host/xhci-pci.c | 42 ++++++++++++++++++++++++++++++++++++++++++
>>   drivers/usb/host/xhci.h     |  6 ++++++
>>   2 files changed, 48 insertions(+)
>>
>> diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
>> index 280dde9..3e7441a 100644
>> --- a/drivers/usb/host/xhci-pci.c
>> +++ b/drivers/usb/host/xhci-pci.c
>> @@ -27,6 +27,8 @@
>>   #include "xhci.h"
>>   #include "xhci-trace.h"
>>   
>> +#define	PORT_WAKE_BITS	(PORT_WKOC_E | PORT_WKDISC_E | PORT_WKCONN_E)
>> +
>>   /* Device for a quirk */
>>   #define PCI_VENDOR_ID_FRESCO_LOGIC	0x1b73
>>   #define PCI_DEVICE_ID_FRESCO_LOGIC_PDK	0x1000
>> @@ -126,6 +128,7 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci)
>>   		 */
>>   		xhci->quirks |= XHCI_SPURIOUS_REBOOT;
>>   		xhci->quirks |= XHCI_AVOID_BEI;
>> +		xhci->quirks |= XHCI_DISABLE_PORT_WOB;
>>   	}
>>   	if (pdev->vendor == PCI_VENDOR_ID_INTEL &&
>>   	    (pdev->device == PCI_DEVICE_ID_INTEL_LYNXPOINT_XHCI ||
>> @@ -279,6 +282,42 @@ static void xhci_pci_remove(struct pci_dev *dev)
>>   }
>>   
>>   #ifdef CONFIG_PM
>> +static void xhci_disable_port_wake_bits(struct xhci_hcd *xhci)
>> +{
>> +	int port_index;
>> +	__le32 __iomem **port_array;
>> +	unsigned long flags;
>> +	u32 t1, t2;
>> +
>> +	spin_lock_irqsave(&xhci->lock, flags);
>> +
>> +	/* disble usb3 ports Wake bits*/
>> +	port_index = xhci->num_usb3_ports;
>> +	port_array = xhci->usb3_ports;
>> +	while (port_index--) {
>> +		t1 = readl(port_array[port_index]);
>> +		t2 = xhci_port_state_to_neutral(t1);
>> +		t2 &= ~PORT_WAKE_BITS;
>> +		t1 = xhci_port_state_to_neutral(t1);
>> +		if (t1 != t2)
>> +			writel(t2, port_array[port_index]);
>> +	}
>> +
>> +	/* disble usb2 ports Wake bits*/
>> +	port_index = xhci->num_usb2_ports;
>> +	port_array = xhci->usb2_ports;
>> +	while (port_index--) {
>> +		t1 = readl(port_array[port_index]);
>> +		t2 = xhci_port_state_to_neutral(t1);
>> +		t2 &= ~PORT_WAKE_BITS;
>> +		t1 = xhci_port_state_to_neutral(t1);
>> +		if (t1 != t2)
>> +			writel(t2, port_array[port_index]);
>> +	}
>> +
>> +	spin_unlock_irqrestore(&xhci->lock, flags);
>> +}
>> +
>>   static int xhci_pci_suspend(struct usb_hcd *hcd, bool do_wakeup)
>>   {
>>   	struct xhci_hcd	*xhci = hcd_to_xhci(hcd);
>> @@ -291,6 +330,9 @@ static int xhci_pci_suspend(struct usb_hcd *hcd, bool do_wakeup)
>>   	if (xhci->quirks & XHCI_COMP_MODE_QUIRK)
>>   		pdev->no_d3cold = true;
>>   
>> +	if (xhci->quirks & XHCI_DISABLE_PORT_WOB && !do_wakeup)
>> +		xhci_disable_port_wake_bits(xhci);
>> +
>>   	return xhci_suspend(xhci);
>>   }
> There are two things wrong here.  First, this should not be a quirk.
> The Wake-On bits should be disabled whenever they aren't needed, on
> every controller.
>
> Second, this code (or something like it) belongs in xhci.c or
> xhci-hub.c, not xhci-pci.c.  This is because it should apply to all
> xHCI controllers, not just the PCI-based ones.
Hi Alan,

I agree with you. I will resubmit my patches.

BR,
baolu

>
> (In fact, instead of disabling the Wake-On bits when the controller is
> suspended and do_wakeup is 0, it probably would be better to leave them
> disabled normally and then _enable_ them if do_wakeup is 1.)
>
> Alan Stern
>