1<html><head><meta http-equiv="Content-Type" content="text/html; charset=ANSI_X3.4-1968"><title>pci_msi_vec_count</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1"><link rel="home" href="index.html" title="The Linux Kernel API"><link rel="up" href="ch09s05.html" title="PCI Support Library"><link rel="prev" href="API-pci-dev-present.html" title="pci_dev_present"><link rel="next" href="API-pci-msix-vec-count.html" title="pci_msix_vec_count"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="3" align="center"><span class="phrase">pci_msi_vec_count</span></th></tr><tr><td width="20%" align="left"><a accesskey="p" href="API-pci-dev-present.html">Prev</a>&#160;</td><th width="60%" align="center">PCI Support Library</th><td width="20%" align="right">&#160;<a accesskey="n" href="API-pci-msix-vec-count.html">Next</a></td></tr></table><hr></div><div class="refentry"><a name="API-pci-msi-vec-count"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>pci_msi_vec_count &#8212; 
2  Return the number of MSI vectors a device can send
3 </p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><div class="funcsynopsis"><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">int <b class="fsfunc">pci_msi_vec_count </b>(</code></td><td>struct pci_dev * <var class="pdparam">dev</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer">&#160;</div></div></div><div class="refsect1"><a name="idp1126819788"></a><h2>Arguments</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>dev</code></em></span></dt><dd><p>
4     device to report about
5    </p></dd></dl></div></div><div class="refsect1"><a name="idp1126821388"></a><h2>Description</h2><p>
6   This function returns the number of MSI vectors a device requested via
7   Multiple Message Capable register. It returns a negative errno if the
8   device is not capable sending MSI interrupts. Otherwise, the call succeeds
9   and returns a power of two, up to a maximum of 2^5 (32), according to the
10   MSI specification.
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