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

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

SYNOPSIS
     #include <machine/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 allocate
     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 con-
              tains 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 con-
              tains 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.  Similarly,
     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
     This section describes places within the NetBSD source tree where actual
     code implementing or using the machine-independent ISAPNP subsystem can
     be found.  All pathnames are relative to /usr/src.

     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.

NetBSD 5.0_STABLE                June 19, 2001               NetBSD 5.0_STABLE
