Modifying DDI 7 DSP files

Several DSP files have major modifications for the DDI 8 interface. To accomodate these, Interface(DSP/4dsp) introduces the concept of entry-type, with drivers for DDI 8 and later versions define as entry-type 1 and drivers for older DDI drivers define as entry-type 0. This distinction is used throughout the manual pages for the DSP files and in this discussion.

The changes to the DSP files are summarized as follows. See the manual pages for detailed information.

Master(4dsp)

• Include the $interface ddi 8 or $interface ddi 8mp string.

• Remove any $entry lines.

• Replace the prefix field in the last non-comment line with a dash (--).

• Delete the order, bmaj, and cmaj fields from the last non-comment line.

• Remove the following characteristic flags: b, c, d, e, k, m, o, u, C, F, K, L, S.

• For DDI 8 pseudo-drivers, add the R characteristic.

Node(4dsp)

Node files for drivers must be modified as follows:

• Add a $maxchan line at the top of the Node file to define the largest channel number that is accessible by the driver instance. For drivers that only use one channel, $maxchan 0 is appropriate. See ``Channel number''.

• Drivers that support more than one node per device must set %i in the node-name field to create a unique node for each instance of this device. See the Node(DSP/4dsp) manual page for more information and examples. Note that %i must be set for all drivers on some early releases of SVR5.

• Remove all lines that define hardcoded instances for your driver. The %i replaces these.

• Remove the offset for the type field that is used for multiple major numbers for driver versions prior to DDI 8. In other words, c:2, that defines a character major offset of 2, becomes just c.

• The 4th field is redefined to indicate the channel number rather than the minor number.

Here are sample Node files for the same device in DDI 7 and DDI 8:

   #DDI 7 version Node(4dsp) file
   shrk    mdi/shrk       c:0     0       0       0       600
   shrk    mdi/shrk       c:0     1       0       0       600
   shrk    mdi/shrk       c:0     2       0       0       600
   shrk    mdi/shrk       c:0     3       0       0       600

   #DDI 8 version Node(4dsp) file
   $maxchan 0
   shrk    mdi/shrk%i     c       0       0       0       600

Ftab(4dsp)

Remove this file; it is ignored for entry-type 1 files.