ISAPNP(9)						   BSD Kernel Developer's Manual						 ISAPNP(9)

NAME

     ISAPNP, isapnp_devmatch, isapnp_config, isapnp_unconfig -- Plug 'n' Play ISA bus

SYNOPSIS

     #include <sys/bus.h>
     #include <dev/isa/isareg.h>
     #include <dev/isa/isavar.h>
     #include <dev/isapnp/isapnpreg.h>
     #include <dev/isapnp/isapnpvar.h>
     #include <dev/isapnp/isapnpdevs.h>

     int
     isapnp_devmatch(const struct isapnp_attach_args *ipa, const struct isapnp_devinfo *dinfo, int *variant);

     int
     isapnp_config(bus_space_tag_t iot, bus_space_tag_t memt, struct isapnp_attach_args *ipa);

     void
     isapnp_unconfig(bus_space_tag_t iot, bus_space_tag_t memt, struct isapnp_attach_args *ipa);

DESCRIPTION

     The machine-independent ISAPNP subsystem provides support for ISAPNP devices.  ISAPNP devices were developed to support "plug and play" con-
     nection on the ISA bus.  In all other aspects, the ISAPNP bus is same as the ISA bus (see isa(9)).

     Devices on the ISAPNP bus are uniquely identified by a 7-character string.  Resources, such as I/O address space and interrupts, should be
     allocated to the devices by the machine firmware.	On some machine the firmware seems doesn't work correctly and NetBSD will attempt to allo-
     cate resources as necessary.

DATA TYPES

     Drivers attached to the ISAPNP bus will make use of the following data types:

     struct isapnp_matchinfo
	      NetBSD kernel contains a database of known ISAPNP devices.  Each entry in the database has a struct isapnp_matchinfo.  It contains
	      the following members:

		      const char *name; 	      /* device id string */
		      int variant;		      /* variant flag */

     struct isapnp_devinfo
	      Defines the devices supported by a driver.  It contains pointer to an array of supported struct isapnp_matchinfo structures and a
	      pointer to another array of compatibility devices.  It contains the following members:

		      struct isapnp_matchinfo *devlogic;
		      int nlogic;
		      struct isapnp_matchinfo *devcompat;
		      int ncompat;

     struct isapnp_region
	      Describes ISAPNP bus-space regions.  It contains the following members:

		      bus_space_handle_t h;
		      uint32_t base;
		      uint32_t length;

     struct isapnp_pin
	      Describes the wiring of interrupts and DMA pins from the ISAPNP bus onto the host processor.  It contains the following members:

		      uint8_t  num;
		      uint8_t  flags:4;
		      uint8_t  type:4;
		      uint16_t bits;

     struct isapnp_attach_args
	      A structure used to inform the driver of the device properties.  It contains the following members:

		      bus_space_tag_t ipa_iot;	      /* isa i/o space tag */
		      bus_space_tag_t ipa_memt;       /* isa mem space tag */
		      bus_dma_tag_t   ipa_dmat;       /* isa dma tag */
		      isa_chipset_tag_t       ipa_ic;
		      struct isapnp_region    ipa_io[ISAPNP_NUM_IO];
		      struct isapnp_region    ipa_mem[ISAPNP_NUM_MEM];
		      struct isapnp_region    ipa_mem32[ISAPNP_NUM_MEM32];
		      struct isapnp_pin       ipa_irq[ISAPNP_NUM_IRQ];
		      struct isapnp_pin       ipa_drq[ISAPNP_NUM_DRQ];

FUNCTIONS

     isapnp_devmatch(ipa, dinfo, variant)
	      Matches the device described by the attachment ipa with the device-match information in dinfo.  If the device is matched,
	      isapnp_devmatch() returns a non-zero value and variant is the flag describing the device variant.  isapnp_devmatch() returns zero if
	      the device is not found.

     isapnp_config(iot, memt, ipa)
	      Allocate device resources specified by ipa.  The device is mapped into the I/O and memory bus spaces specified by bus-space tags iot
	      and memt respectively.  The ipa_io, ipa_mem, ipa_mem32, ipa_irq, and ipa_drq members of ipa are updated to reflect the allocated and
	      mapped resources.  isapnp_config() returns zero on success and non-zero on error.

     isapnp_unconfig(iot, memt, ipa)
	      Free the resources allocated by isapnp_config().

AUTOCONFIGURATION

     During autoconfiguration, an ISAPNP driver will receive a pointer to struct isapnp_attach_args describing the device attached to the ISAPNP
     bus.  Drivers match the device using ispnp_devmatch().

     During the driver attach step, driver should initially allocate and map resources using isapnp_config().  The I/O (memory) bus-space
     resources can be accessed using the bus-space tag ipa_iot (ipa_memt) and the bus-space handle ipa_io[0].h (ipa_mem[0].h) members of ipa.

     Interrupts should be established using isa_intr_establish() (see isa(9)) with the IRQ specified by the ipa_irq[0].num member of ipa.  Simi-
     larly, the standard isa(9) DMA interface should be used with the ipa_drq[0].num member of ipa.

DMA SUPPORT

     Extensive DMA facilities are provided through the isa(9) DMA facilities.

CODE REFERENCES

     The ISAPNP subsystem itself is implemented within the file sys/dev/isapnp/isapnp.c.  The database of the known devices exists within the file
     sys/dev/isapnp/isapnpdevs.c and is generated automatically from the file sys/dev/isapnp/isapnpdevs.  New devices should be added to this
     file.  The database can be regenerated using the Makefile sys/dev/isapnp/Makefile.isapnpdevs.

SEE ALSO

     isa(4), isapnp(4), pnpbios(4), autoconf(9), bus_dma(9), bus_space(9), driver(9), isa(9)

     Plug and Play ISA Specification V1.0a, May 5 1994.

HISTORY

     The machine-independent ISAPNP subsystem appear in NetBSD 1.3.

BSD
								   June 19, 2001							       BSD