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authorJim Harris <james.r.harris@intel.com>2017-05-02 17:20:59 +0300
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2017-05-18 17:59:06 +0300
commitacec09e67dc450d09a912735855326c3f1146a37 (patch)
treed723684cdea22ba17f66c3c41f09fe1f72de7724 /drivers/uio
parent98e959d44bcaac70c3056578122b5ce777ff42f0 (diff)
downloadlinux-acec09e67dc450d09a912735855326c3f1146a37.tar.xz
uio/uio_pci_generic: don't fail probe if pdev->irq == NULL
Some userspace drivers and frameworks only poll and do not require interrupts to be available and enabled on the PCI device. So remove the requirement that an IRQ is assigned. If an IRQ is not assigned and a userspace driver tries to read()/write(), the generic uio framework will just return -EIO. This allows binding uio_pci_generic to devices which cannot get an IRQ assigned, such as an NVMe controller behind Intel Volume Management Device (VMD), since VMD does not support INTx interrupts. Signed-off-by: Jim Harris <james.r.harris@intel.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/uio')
-rw-r--r--drivers/uio/uio_pci_generic.c20
1 files changed, 9 insertions, 11 deletions
diff --git a/drivers/uio/uio_pci_generic.c b/drivers/uio/uio_pci_generic.c
index d0b508b68f3c..a56fdf972dbe 100644
--- a/drivers/uio/uio_pci_generic.c
+++ b/drivers/uio/uio_pci_generic.c
@@ -66,14 +66,7 @@ static int probe(struct pci_dev *pdev,
return err;
}
- if (!pdev->irq) {
- dev_warn(&pdev->dev, "No IRQ assigned to device: "
- "no support for interrupts?\n");
- pci_disable_device(pdev);
- return -ENODEV;
- }
-
- if (!pci_intx_mask_supported(pdev)) {
+ if (pdev->irq && !pci_intx_mask_supported(pdev)) {
err = -ENODEV;
goto err_verify;
}
@@ -86,10 +79,15 @@ static int probe(struct pci_dev *pdev,
gdev->info.name = "uio_pci_generic";
gdev->info.version = DRIVER_VERSION;
- gdev->info.irq = pdev->irq;
- gdev->info.irq_flags = IRQF_SHARED;
- gdev->info.handler = irqhandler;
gdev->pdev = pdev;
+ if (pdev->irq) {
+ gdev->info.irq = pdev->irq;
+ gdev->info.irq_flags = IRQF_SHARED;
+ gdev->info.handler = irqhandler;
+ } else {
+ dev_warn(&pdev->dev, "No IRQ assigned to device: "
+ "no support for interrupts?\n");
+ }
err = uio_register_device(&pdev->dev, &gdev->info);
if (err)