2014-11-05 05:17:35

by Lu Baolu

[permalink] [raw]
Subject: [PATCH v3 0/3] Rework "xhci: clear root port wake on bits if controller isn't wake-up capable"

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.

Changes in v3:
* Need to consider run-time suspend as well.
* Change "wake-up capable" to "allowed to do wakeup"
in both comments and patch description.
* Add "Suggested-by: Alan Stern"

Changes in v2:
* Should not be a quirk.
* Should be applied to all xhci controllers.

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 | 2 +-
drivers/usb/host/xhci-plat.c | 10 +++++++++-
drivers/usb/host/xhci.c | 44 +++++++++++++++++++++++++++++++++++++++++++-
drivers/usb/host/xhci.h | 4 ++--
5 files changed, 56 insertions(+), 9 deletions(-)

--
1.9.1


2014-11-05 05:17:46

by Lu Baolu

[permalink] [raw]
Subject: [PATCH v3 1/3] usb: xhci: Revert "xhci: clear root port wake on bits if controller isn't wake-up capable"

This reverts commit ff8cbf250b448aac35589f6075082c3fcad8a8fe.

Commit ff8cbf250b448aac35589f6075082c3fcad8a8fe triggers the bug logged at

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

Signed-off-by: Lu Baolu <[email protected]>
Reported-by: Dmitry Nezhevenko <[email protected]>
---
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

2014-11-05 05:17:48

by Lu Baolu

[permalink] [raw]
Subject: [PATCH v3 3/3] usb: xhci: fix comment for PORT_DEV_REMOVE

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

Signed-off-by: Lu Baolu <[email protected]>
Reported-by: Juro Bystricky <[email protected]>
---
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 d745715..ab36bbb 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

2014-11-05 05:17:44

by Lu Baolu

[permalink] [raw]
Subject: [PATCH v3 2/3] usb: xhci: This reworks ff8cbf250b448aac35589f6075082c3fcad8a8fe

xhci: clear root port wake on bits if controller isn't allowed to do wakeup

When system is being suspended, if host device is not allowed to do wakeup,
xhci_suspend() needs to clear all root port wake on bits. Otherwise, some
platforms may generate spurious wakeup, even if PCI PME# is disabled.

Signed-off-by: Lu Baolu <[email protected]>
Suggested-by: Alan Stern <[email protected]>
---
drivers/usb/host/xhci-pci.c | 2 +-
drivers/usb/host/xhci-plat.c | 10 +++++++++-
drivers/usb/host/xhci.c | 44 +++++++++++++++++++++++++++++++++++++++++++-
drivers/usb/host/xhci.h | 2 +-
4 files changed, 54 insertions(+), 4 deletions(-)

diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c
index 280dde9..d3fa3c2 100644
--- a/drivers/usb/host/xhci-pci.c
+++ b/drivers/usb/host/xhci-pci.c
@@ -291,7 +291,7 @@ static int xhci_pci_suspend(struct usb_hcd *hcd, bool do_wakeup)
if (xhci->quirks & XHCI_COMP_MODE_QUIRK)
pdev->no_d3cold = true;

- return xhci_suspend(xhci);
+ return xhci_suspend(xhci, do_wakeup);
}

static int xhci_pci_resume(struct usb_hcd *hcd, bool hibernated)
diff --git a/drivers/usb/host/xhci-plat.c b/drivers/usb/host/xhci-plat.c
index 3d78b0c..646300c 100644
--- a/drivers/usb/host/xhci-plat.c
+++ b/drivers/usb/host/xhci-plat.c
@@ -204,7 +204,15 @@ static int xhci_plat_suspend(struct device *dev)
struct usb_hcd *hcd = dev_get_drvdata(dev);
struct xhci_hcd *xhci = hcd_to_xhci(hcd);

- return xhci_suspend(xhci);
+ /*
+ * xhci_suspend() needs `do_wakeup` to know whether host is allowed
+ * to do wakeup during suspend. Since xhci_plat_suspend is currently
+ * only designed for system suspend, device_may_wakeup() is enough
+ * to dertermine whether host is allowed to do wakeup. Need to
+ * reconsider this when xhci_plat_suspend enlarges its scope, e.g.,
+ * also applies to runtime suspend.
+ */
+ return xhci_suspend(xhci, device_may_wakeup(dev));
}

static int xhci_plat_resume(struct device *dev)
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 2a5d45b..70d607b 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -35,6 +35,8 @@
#define DRIVER_AUTHOR "Sarah Sharp"
#define DRIVER_DESC "'eXtensible' Host Controller (xHC) Driver"

+#define PORT_WAKE_BITS (PORT_WKOC_E | PORT_WKDISC_E | PORT_WKCONN_E)
+
/* Some 0.95 hardware can't handle the chain bit on a Link TRB being cleared */
static int link_quirk;
module_param(link_quirk, int, S_IRUGO | S_IWUSR);
@@ -851,13 +853,49 @@ static void xhci_clear_command_ring(struct xhci_hcd *xhci)
xhci_set_cmd_ring_deq(xhci);
}

+static void xhci_disable_port_wake_on_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);
+}
+
/*
* Stop HC (not bus-specific)
*
* This is called when the machine transition into S3/S4 mode.
*
*/
-int xhci_suspend(struct xhci_hcd *xhci)
+int xhci_suspend(struct xhci_hcd *xhci, bool do_wakeup)
{
int rc = 0;
unsigned int delay = XHCI_MAX_HALT_USEC;
@@ -868,6 +906,10 @@ int xhci_suspend(struct xhci_hcd *xhci)
xhci->shared_hcd->state != HC_STATE_SUSPENDED)
return -EINVAL;

+ /* Clear root port wake on bits if wakeup not allowed. */
+ if (!do_wakeup)
+ xhci_disable_port_wake_on_bits(xhci);
+
/* Don't poll the roothubs on bus suspend. */
xhci_dbg(xhci, "%s: stopping port polling.\n", __func__);
clear_bit(HCD_FLAG_POLL_RH, &hcd->flags);
diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
index df76d64..d745715 100644
--- a/drivers/usb/host/xhci.h
+++ b/drivers/usb/host/xhci.h
@@ -1746,7 +1746,7 @@ int xhci_gen_setup(struct usb_hcd *hcd, xhci_get_quirks_t get_quirks);
void xhci_init_driver(struct hc_driver *drv, int (*setup_fn)(struct usb_hcd *));

#ifdef CONFIG_PM
-int xhci_suspend(struct xhci_hcd *xhci);
+int xhci_suspend(struct xhci_hcd *xhci, bool do_wakeup);
int xhci_resume(struct xhci_hcd *xhci, bool hibernated);
#else
#define xhci_suspend NULL
--
1.9.1

2014-11-05 21:24:06

by Alan Stern

[permalink] [raw]
Subject: Re: [PATCH v3 2/3] usb: xhci: This reworks ff8cbf250b448aac35589f6075082c3fcad8a8fe

On Wed, 5 Nov 2014, Lu Baolu wrote:

> xhci: clear root port wake on bits if controller isn't allowed to do wakeup
>
> When system is being suspended, if host device is not allowed to do wakeup,
> xhci_suspend() needs to clear all root port wake on bits. Otherwise, some
> platforms may generate spurious wakeup, even if PCI PME# is disabled.
>
> Signed-off-by: Lu Baolu <[email protected]>
> Suggested-by: Alan Stern <[email protected]>

This looks pretty good now.

> +static void xhci_disable_port_wake_on_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]);

Why not just do:

t1 = readl(port_array[port_index]);
t1 = xhci_port_state_to_neutral(t1);
t2 = t1 & ~PORT_WAKE_BITS;
if (t1 != t2) ...

Apart from that minor point,

Acked-by: Alan Stern <[email protected]>

Alan Stern

2014-11-06 02:18:47

by Lu Baolu

[permalink] [raw]
Subject: Re: [PATCH v3 2/3] usb: xhci: This reworks ff8cbf250b448aac35589f6075082c3fcad8a8fe


On 11/6/2014 5:24 AM, Alan Stern wrote:
> On Wed, 5 Nov 2014, Lu Baolu wrote:
>
>> xhci: clear root port wake on bits if controller isn't allowed to do wakeup
>>
>> When system is being suspended, if host device is not allowed to do wakeup,
>> xhci_suspend() needs to clear all root port wake on bits. Otherwise, some
>> platforms may generate spurious wakeup, even if PCI PME# is disabled.
>>
>> Signed-off-by: Lu Baolu <[email protected]>
>> Suggested-by: Alan Stern <[email protected]>
> This looks pretty good now.
>
>> +static void xhci_disable_port_wake_on_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]);
> Why not just do:
>
> t1 = readl(port_array[port_index]);
> t1 = xhci_port_state_to_neutral(t1);
> t2 = t1 & ~PORT_WAKE_BITS;
> if (t1 != t2) ...
Right, this looks better. I will test and resend the patches with this
change.

>
> Apart from that minor point,
>
> Acked-by: Alan Stern <[email protected]>
>
> Alan Stern
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-usb" in
> the body of a message to [email protected]
> More majordomo info at http://vger.kernel.org/majordomo-info.html