[PATCH] USB: core: Disable LPM only for non-suspended ports

[PATCH] USB: core: Disable LPM only for non-suspended ports

[Kai-Heng Feng]

There's USB error when tegra board is shutting down:
[  180.919315] usb 2-3: Failed to set U1 timeout to 0x0,error code -113
[  180.919995] usb 2-3: Failed to set U1 timeout to 0xa,error code -113
[  180.920512] usb 2-3: Failed to set U2 timeout to 0x4,error code -113
[  186.157172] tegra-xusb 3610000.usb: xHCI host controller not responding, assume dead
[  186.157858] tegra-xusb 3610000.usb: HC died; cleaning up
[  186.317280] tegra-xusb 3610000.usb: Timeout while waiting for evaluate context command

The issue is caused by disabling LPM on already suspended ports.

For USB2 LPM, the LPM is already disabled during port suspend. For USB3
LPM, port won't transit to U1/U2 when it's already suspended in U3,
hence disabling LPM is only needed for ports that are not suspended.

Cc: Wayne Chang <waynec@nvidia.com>
Fixes: d920a2ed8620 ("usb: Disable USB3 LPM at shutdown")
Signed-off-by: Kai-Heng Feng <kaihengf@nvidia.com>
---
 drivers/usb/core/port.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/core/port.c b/drivers/usb/core/port.c
index e7da2fca11a4..d50b9e004e76 100644
--- a/drivers/usb/core/port.c
+++ b/drivers/usb/core/port.c
@@ -452,10 +452,11 @@ static int usb_port_runtime_suspend(struct device *dev)
 static void usb_port_shutdown(struct device *dev)
 {
 	struct usb_port *port_dev = to_usb_port(dev);
+	struct usb_device *udev = port_dev->child;
 
-	if (port_dev->child) {
-		usb_disable_usb2_hardware_lpm(port_dev->child);
-		usb_unlocked_disable_lpm(port_dev->child);
+	if (udev && !pm_runtime_suspended(&udev->dev)) {
+		usb_disable_usb2_hardware_lpm(udev);
+		usb_unlocked_disable_lpm(udev);
 	}
 }
 
-- 
2.47.0

Re: [PATCH] USB: core: Disable LPM only for non-suspended ports

[Greg KH]

On Thu, Dec 05, 2024 at 04:42:05PM +0800, Kai-Heng Feng wrote:
> There's USB error when tegra board is shutting down:
> [  180.919315] usb 2-3: Failed to set U1 timeout to 0x0,error code -113
> [  180.919995] usb 2-3: Failed to set U1 timeout to 0xa,error code -113
> [  180.920512] usb 2-3: Failed to set U2 timeout to 0x4,error code -113
> [  186.157172] tegra-xusb 3610000.usb: xHCI host controller not responding, assume dead
> [  186.157858] tegra-xusb 3610000.usb: HC died; cleaning up
> [  186.317280] tegra-xusb 3610000.usb: Timeout while waiting for evaluate context command
> 
> The issue is caused by disabling LPM on already suspended ports.
> 
> For USB2 LPM, the LPM is already disabled during port suspend. For USB3
> LPM, port won't transit to U1/U2 when it's already suspended in U3,
> hence disabling LPM is only needed for ports that are not suspended.
> 
> Cc: Wayne Chang <waynec@nvidia.com>
> Fixes: d920a2ed8620 ("usb: Disable USB3 LPM at shutdown")
> Signed-off-by: Kai-Heng Feng <kaihengf@nvidia.com>
> ---
>  drivers/usb/core/port.c | 7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/usb/core/port.c b/drivers/usb/core/port.c
> index e7da2fca11a4..d50b9e004e76 100644
> --- a/drivers/usb/core/port.c
> +++ b/drivers/usb/core/port.c
> @@ -452,10 +452,11 @@ static int usb_port_runtime_suspend(struct device *dev)
>  static void usb_port_shutdown(struct device *dev)
>  {
>  	struct usb_port *port_dev = to_usb_port(dev);
> +	struct usb_device *udev = port_dev->child;
>  
> -	if (port_dev->child) {
> -		usb_disable_usb2_hardware_lpm(port_dev->child);
> -		usb_unlocked_disable_lpm(port_dev->child);
> +	if (udev && !pm_runtime_suspended(&udev->dev)) {
> +		usb_disable_usb2_hardware_lpm(udev);
> +		usb_unlocked_disable_lpm(udev);
>  	}
>  }
>  
> -- 
> 2.47.0
> 
> 

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
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