Re: [PATCH RFC 05/77] PCI/MSI: Convert pci_msix_table_size() to a public interface

On Mon, Oct 07, 2013 at 02:10:43PM -0400, Tejun Heo wrote:

On Wed, Oct 02, 2013 at 12:48:21PM +0200, Alexander Gordeev wrote:

quoted

Make pci_msix_table_size() to return a error code if the device
does not support MSI-X. This update is needed to facilitate a
forthcoming re-design MSI/MSI-X interrupts enabling pattern.

Device drivers will use this interface to obtain maximum number
of MSI-X interrupts the device supports and use that value in
the following call to pci_enable_msix() interface.

Hmmm... I probably missed something but why is this necessary?  To
discern between -EINVAL and -ENOSPC?  If so, does that really matter?

pci_msix_table_size() is kind of helper and returns 0 if a device does
not have MSI-X table. If we want drivers to use it we need return -EINVAL
for MSI-X incapable/disabled devices. Nothing about -ENOSPC.

tejun

-- 
Regards,
Alexander Gordeev
agordeev@redhat.com