summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorCristian Ciocaltea <cristian.ciocaltea@collabora.com>2025-09-02 15:15:46 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2025-09-25 18:52:32 +0200
commite40b984b6c4ce3f80814f39f86f87b2a48f2e662 (patch)
treed00dae8bcceccb4867eb8575a022d0b9a0a562c8
parent264a58e60c5c93b358818f523eb4911190c8b8d7 (diff)
usb: vhci-hcd: Prevent suspending virtually attached devices
The VHCI platform driver aims to forbid entering system suspend when at least one of the virtual USB ports are bound to an active USB/IP connection. However, in some cases, the detection logic doesn't work reliably, i.e. when all devices attached to the virtual root hub have been already suspended, leading to a broken suspend state, with unrecoverable resume. Ensure the virtually attached devices do not enter suspend by setting the syscore PM flag. Note this is currently limited to the client side only, since the server side doesn't implement system suspend prevention. Fixes: 04679b3489e0 ("Staging: USB/IP: add client driver") Signed-off-by: Cristian Ciocaltea <cristian.ciocaltea@collabora.com> Acked-by: Shuah Khan <skhan@linuxfoundation.org> Link: https://lore.kernel.org/r/20250902-vhci-hcd-suspend-fix-v3-1-864e4e833559@collabora.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--drivers/usb/usbip/vhci_hcd.c22
1 files changed, 22 insertions, 0 deletions
diff --git a/drivers/usb/usbip/vhci_hcd.c b/drivers/usb/usbip/vhci_hcd.c
index e70fba9f55d6..0d6c10a8490c 100644
--- a/drivers/usb/usbip/vhci_hcd.c
+++ b/drivers/usb/usbip/vhci_hcd.c
@@ -765,6 +765,17 @@ static int vhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb, gfp_t mem_flag
ctrlreq->wValue, vdev->rhport);
vdev->udev = usb_get_dev(urb->dev);
+ /*
+ * NOTE: A similar operation has been done via
+ * USB_REQ_GET_DESCRIPTOR handler below, which is
+ * supposed to always precede USB_REQ_SET_ADDRESS.
+ *
+ * It's not entirely clear if operating on a different
+ * usb_device instance here is a real possibility,
+ * otherwise this call and vdev->udev assignment above
+ * should be dropped.
+ */
+ dev_pm_syscore_device(&vdev->udev->dev, true);
usb_put_dev(old);
spin_lock(&vdev->ud.lock);
@@ -785,6 +796,17 @@ static int vhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb, gfp_t mem_flag
"Not yet?:Get_Descriptor to device 0 (get max pipe size)\n");
vdev->udev = usb_get_dev(urb->dev);
+ /*
+ * Set syscore PM flag for the virtually attached
+ * devices to ensure they will not enter suspend on
+ * the client side.
+ *
+ * Note this doesn't have any impact on the physical
+ * devices attached to the host system on the server
+ * side, hence there is no need to undo the operation
+ * on disconnect.
+ */
+ dev_pm_syscore_device(&vdev->udev->dev, true);
usb_put_dev(old);
goto out;