From da27f4b3ec77a04672345381cbfeeb841d427327 Mon Sep 17 00:00:00 2001 From: Bjorn Helgaas Date: Thu, 22 Aug 2013 14:45:21 -0600 Subject: [PATCH] PCI: Add comment about needing pci_msi_off() even when CONFIG_PCI_MSI=n Per f5f2b13129 ("msi: sanely support hardware level msi disabling"), we want pci_msi_off() to work even if MSI support is not compiled into the kernel, and there are existing callers that use it when CONFIG_PCI_MSI=n. This adds a comment to that effect. No functional change. Signed-off-by: Bjorn Helgaas --- drivers/pci/pci.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 69dcd32e0fe8..42e5f86e2387 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -3059,18 +3059,23 @@ bool pci_check_and_unmask_intx(struct pci_dev *dev) EXPORT_SYMBOL_GPL(pci_check_and_unmask_intx); /** - * pci_msi_off - disables any msi or msix capabilities + * pci_msi_off - disables any MSI or MSI-X capabilities * @dev: the PCI device to operate on * - * If you want to use msi see pci_enable_msi and friends. - * This is a lower level primitive that allows us to disable - * msi operation at the device level. + * If you want to use MSI, see pci_enable_msi() and friends. + * This is a lower-level primitive that allows us to disable + * MSI operation at the device level. */ void pci_msi_off(struct pci_dev *dev) { int pos; u16 control; + /* + * This looks like it could go in msi.c, but we need it even when + * CONFIG_PCI_MSI=n. For the same reason, we can't use + * dev->msi_cap or dev->msix_cap here. + */ pos = pci_find_capability(dev, PCI_CAP_ID_MSI); if (pos) { pci_read_config_word(dev, pos + PCI_MSI_FLAGS, &control);