+ <sect2><title>Write specific ATA shadow register</title>
+ <programlisting>
+void (*sff_set_devctl)(struct ata_port *ap, u8 ctl);
+ </programlisting>
+
+ <para>
+ Write the device control ATA shadow register to the hardware.
+ Most drivers don't need to define this.
+ </para>
+
+ </sect2>
+