From: Michael Ellerman Date: Wed, 11 Feb 2009 11:27:02 +0000 (+1100) Subject: PCI/MSI: Allow arch code to return the number of MSI-X available X-Git-Tag: v2.6.30-rc1~419^2~61 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=b5fbf53324f65646154e172af350674d5a2a1629;p=pandora-kernel.git PCI/MSI: Allow arch code to return the number of MSI-X available There is code in msix_capability_init() which, when the requested number of MSI-X couldn't be allocated, calculates how many MSI-X /could/ be allocated and returns that to the driver. That allows the driver to then make a second request, with a number of MSIs that should succeed. The current code requires the arch code to setup as many msi_descs as it can, and then return to the generic code. On some platforms the arch code may already know how many MSI-X it can allocate, before it sets up any of the msi_descs. So change the logic such that if the arch code returns a positive error code, that is taken to be the number of MSI-X that could be allocated. If the error code is negative we still calculate the number available using the old method. Because it's a little subtle, make sure the error return code from arch_setup_msi_irq() is always negative. That way only implementations of arch_setup_msi_irqs() need to be careful about returning a positive error code. Signed-off-by: Michael Ellerman Signed-off-by: Jesse Barnes --- Reading git-diff-tree failed