[LinuxBIOS] question about pnp_dev_info structure in it8716f's superio.c

[Ward Vandewege]

Hi there,

I would like some advice about the pnp_dev_info structure. It's used in
superio.c for it8716f, for instance.

This is what's currently in the tree:

  static struct pnp_info pnp_dev_info[] = {
    { &ops, IT8716F_FDC, PNP_IO0 | PNP_IRQ0 | PNP_DRQ0, { 0x07f8, 0}, },
    { &ops, IT8716F_SP1, PNP_IO0 | PNP_IRQ0, { 0x7f8, 0 }, },
    { &ops, IT8716F_SP2, PNP_IO0 | PNP_IRQ0, { 0x7f8, 0 }, },
    { &ops, IT8716F_PP, PNP_IO0 | PNP_IRQ0 | PNP_DRQ0, { 0x07f8, 0}, },
    { &ops, IT8716F_KBCK, PNP_IO0 | PNP_IO1 | PNP_IRQ0, { 0x7ff, 0 }, {
0x7ff, 0x4}, },
    { &ops, IT8716F_KBCM, PNP_IRQ0, },
    // No 7 { 0,},
    { &ops, IT8716F_MIDI, PNP_IO0 | PNP_IRQ0, {0x7fe, 0x4}, },
    { &ops, IT8716F_GAME, PNP_IO0, { 0x7ff, 0 }, },
    { &ops, IT8716F_IR, },
  };

The last 2 parameters on the KBCK line are structs of the type 
io_info:

  struct io_info {
    unsigned mask, set;
  };

The io_info structure is used to calculate the size of the pci resource;
putting 0x7f8 works out to 8 bytes if I understand this correctly; 0x7ff
becomes 1 byte.

I added this line for the 'Environmental Controller' that deals with fans and
temperature/voltage sensors:

  { &ops, IT8716F_EC, PNP_IO0 | PNP_IO1 | PNP_IRQ0, { 0x7f8, 0 }, { 0x7f8,
0x4}, },

This seems to work, but I don't fully understand what the io_info values
should be. I'm not sure how I can tell from the datasheet what the sizes
should be. I think they apply to PNP_IO0 and PNP_IO1.

The calculation is done in pnp_get_ioresource in devices/pnp_device.c. 

Also, the 'set' value seems to be unused in this context, which is confusing;
I'm not sure why it is even there?

Thanks,
Ward.

-- 
Ward Vandewege <ward at fsf.org>
Free Software Foundation - Senior System Administrator