DragonFly On-Line Manual Pages

PNP(4)		    DragonFly/i386 Kernel Interfaces Manual		PNP(4)

NAME
     pnp -- support for PnP devices

SYNOPSIS
     controller pnp0

DESCRIPTION
     Support for PnP devices in DragonFly allows the user to override the con-
     figuration of PnP cards, and device drivers to fetch/modify parameters in
     the card's configuration space.

     The manual override mechanism requires the kernel to be compiled with
     options USERCONFIG.  In this case, the kernel keeps a table of fixed size
     (20 entries as a default) where configuration data are held for PnP
     devices.  Each PnP card can contain several independent devices (5 or 6
     is not unusual).

     By booting the kernel with the ``-c'' flag, commands are available to
     modify the configuration of PnP cards.  Commands start with the sequence:
	   pnp CSN LDN
     where CSN and LDN are the Card Select Number and Logical Device Number
     associated to the device.	Following this sequence any combination of the
     following commands can be used:

     irqN line	 Sets the irq line for interrupt 0 or 1 on the card.  Line=0
		 means the line is unused.

     drqN n	 Sets the drq channel used for DMA 0 or 1 on the card.	Chan-
		 nel=4 means the channel is unused.

     portN address
		 Sets the base address for the N-th port's range (N=0..7).
		 address=0 means that the port is not used.

     memN address
		 Sets the base address for the N-th memory's range (N=0..3).
		 address=0 means that the memory range is not used.

     bios	 Makes the PnP device use the configuration set by the BIOS.
		 This is the default, and is generally ok if your BIOS has PnP
		 support.  If BIOS is used, then other parameters are ignored
		 except "flags".

     os 	 Makes the PnP device to use the configuration specified in
		 this entry.

     enable	 Enables the PnP device.

     disable	 Disables the PnP device.

     delete	 Frees the entry used for the device, so that it can be used
		 for another device with a different CSN/LDN pair.

     flags	 Sets the value of a 32-bit flags entry which is passed to the
		 device driver.  This can be used to set special operation
		 modes (e.g. SB vs. WSS emulation on some sound cards, etc.).

     The current content of the table can be printed using the ls command in
     userconfig.  In addition to modifications done by the user, the table
     contains an entry for all logical devices accessed by a PnP device
     driver.

     Modifications to the table will be saved to the boot image on the
     filesystem by the kget(8) command.

DEVICE DRIVER SUPPORT FOR PnP
     PnP devices are automatically recognized and configured by the kernel.  A
     PnP device is identified by the following data structure:

     struct pnp_device {
	     char    *pd_name;
	     char    *(*pd_probe ) (u_long csn, u_long vendor_id);
	     void    (*pd_attach ) (u_long csn, u_long vend_id, char * name,
			 struct isa_device *dev);
	     u_long  *pd_count;
	     u_int   *imask;
	     struct  isa_device dev;
     };

     The probe routine must check that the vendor_id passed is a recognized
     one, that any necessary devices on the card are enabled, and returns a
     NULL value in case of failure or a non-NULL value (generally a pointer to
     the device name) upon success.  In the probe routine, the function
     read_pnp_parms() can be used to check that the logical devices are
     enabled.

     The attach routine should do all the necessary initialization, enable the
     PnP card to ISA accesses, fetch the configuration, and call the ISA
     driver for the device.

SEE ALSO
     pnpbios(4), kget(8)

HISTORY
     The pnp driver first appeared in FreeBSD 2.2.5.

AUTHORS
     PnP support was written by Luigi Rizzo, based on initial work done by
     Sujal Patel.

BUGS
     There is no support for visual configuration of PnP devices.  It would be
     nice to have commands in userconfig to fetch the configuration of PnP
     devices.

DragonFly 4.1		       September 7, 1997		 DragonFly 4.1