diff options
| author | Peter Chen <peter.chen@nxp.com> | 2017-05-17 18:32:02 +0300 |
|---|---|---|
| committer | Leonard Crestez <leonard.crestez@nxp.com> | 2018-08-24 12:41:33 +0300 |
| commit | 938e5fd151ffa4ca9502590b206dbf89d3bf6f3e (patch) | |
| tree | 74b9e8db23a821e2e695734e68fe730d6646df11 /drivers/usb/host | |
| parent | 0d6dd352cc5045b735c1c69999fe9fe5fc35e100 (diff) | |
usb: host: xhci-ring: don't need to clear interrupt pending for MSI enabled hcd
According to xHCI spec Figure 30: Interrupt Throttle Flow Diagram
If PCI Message Signaled Interrupts (MSI or MSI-X) are enabled,
then the assertion of the Interrupt Pending (IP) flag in Figure 30
generates a PCI Dword write. The IP flag is automatically cleared
by the completion of the PCI write.
the MSI enabled HCs don't need to clear interrupt pending bit, but
hcd->irq = 0 doesn't equal to MSI enabled HCD. At some Dual-role
controller software designs, it sets hcd->irq as 0 to avoid HCD
requesting interrupt, and they want to decide when to call usb_hcd_irq
by software.
Signed-off-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/host')
| -rw-r--r-- | drivers/usb/host/xhci-ring.c | 5 | ||||
| -rw-r--r-- | drivers/usb/host/xhci.c | 5 |
2 files changed, 4 insertions, 6 deletions
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index 89a14d5f6ad8..f4f9bc8636b3 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -2770,12 +2770,9 @@ hw_died: */ status |= STS_EINT; writel(status, &xhci->op_regs->status); - /* FIXME when MSI-X is supported and there are multiple vectors */ - /* Clear the MSI-X event interrupt status */ - if (hcd->irq) { + if (!hcd->msi_enabled) { u32 irq_pending; - /* Acknowledge the PCI interrupt */ irq_pending = readl(&xhci->ir_set->irq_pending); irq_pending |= IMAN_IP; writel(irq_pending, &xhci->ir_set->irq_pending); diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index 788dded08871..7e32220ed94f 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -398,9 +398,10 @@ static int xhci_try_enable_msi(struct usb_hcd *hcd) /* fall back to msi*/ ret = xhci_setup_msi(xhci); - if (!ret) - /* hcd->irq is 0, we have MSI */ + if (!ret) { + hcd->msi_enabled = 1; return 0; + } if (!pdev->irq) { xhci_err(xhci, "No msi-x/msi found and no IRQ in BIOS\n"); |