X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=Documentation%2FDocBook%2Fdeviceiobook.tmpl;fp=Documentation%2FDocBook%2Fdeviceiobook.tmpl;h=6f41f2f5c6f6bb656c4f91f6ffcf6a06dcde49b7;hb=64ba3f394c830ec48a1c31b53dcae312c56f1604;hp=90ed23df1f68f6f14c0077d7a196c36c0db08c11;hpb=be1e6109ac94a859551f8e1774eb9a8469fe055c;p=linux-2.6.git

diff --git a/Documentation/DocBook/deviceiobook.tmpl b/Documentation/DocBook/deviceiobook.tmpl
index 90ed23df1..6f41f2f5c 100644
--- a/Documentation/DocBook/deviceiobook.tmpl
+++ b/Documentation/DocBook/deviceiobook.tmpl
@@ -270,6 +270,25 @@ CPU B:  spin_unlock_irqrestore(&dev_lock, flags)
       </para>
     </sect1>
 
+    <sect1>
+      <title>ISA legacy functions</title>
+      <para>
+	On older kernels (2.2 and earlier) the ISA bus could be read or
+	written with these functions and without ioremap being used. This is
+	no longer true in Linux 2.4. A set of equivalent functions exist for
+	easy legacy driver porting. The functions available are prefixed
+	with 'isa_' and are <function>isa_readb</function>,
+	<function>isa_writeb</function>, <function>isa_readw</function>, 
+	<function>isa_writew</function>, <function>isa_readl</function>,
+	<function>isa_writel</function>, <function>isa_memcpy_fromio</function>
+	and <function>isa_memcpy_toio</function>
+      </para>
+      <para>
+	These functions should not be used in new drivers, and will
+	eventually be going away.
+      </para>
+    </sect1>
+
   </chapter>
 
   <chapter>