From: Niklas Neronin Date: Thu, 5 Sep 2024 14:32:56 +0000 (+0300) Subject: usb: xhci: add comments explaining specific interrupt behaviour X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=77d871aeddc360ccd0b0d533e2e2e57eda3975f3;p=users%2Fdwmw2%2Flinux.git usb: xhci: add comments explaining specific interrupt behaviour HCD does not allocate or request interrupt for the xhci driver, but HCD does free and sync xhci interrupts in some cases. Add comment detailing in which cases HCD will free/sync xhci interrupts. Signed-off-by: Niklas Neronin Signed-off-by: Mathias Nyman Link: https://lore.kernel.org/r/20240905143300.1959279-9-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c index b405cff2d6005..d6196c08ea873 100644 --- a/drivers/usb/host/xhci-pci.c +++ b/drivers/usb/host/xhci-pci.c @@ -93,6 +93,10 @@ static const struct xhci_driver_overrides xhci_pci_overrides __initconst = { .update_hub_device = xhci_pci_update_hub_device, }; +/* + * Primary Legacy and MSI IRQ are synced in suspend_common(). + * All MSI-X IRQs and secondary MSI IRQs should be synced here. + */ static void xhci_msix_sync_irqs(struct xhci_hcd *xhci) { struct usb_hcd *hcd = xhci_to_hcd(xhci); @@ -105,13 +109,12 @@ static void xhci_msix_sync_irqs(struct xhci_hcd *xhci) } } -/* Free any IRQs and disable MSI-X */ +/* Legacy IRQ is freed by usb_remove_hcd() or usb_hcd_pci_shutdown() */ static void xhci_cleanup_msix(struct xhci_hcd *xhci) { struct usb_hcd *hcd = xhci_to_hcd(xhci); struct pci_dev *pdev = to_pci_dev(hcd->self.controller); - /* return if using legacy interrupt */ if (hcd->irq > 0) return;