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PCKBPORT(9) Kernel Developer's Manual PCKBPORT(9)
NAME
pckbport, pckbport_attach, pckbport_attach_slot, pckbport_cnattach,
pckbportintr, pckbport_set_inputhandler, pckbport_flush,
pckbport_poll_cmd, pckbport_enqueue_cmd, pckbport_poll_data,
pckbport_set_poll, pckbport_xt_translation, pckbport_slot_enable - PC
keyboard port interface
SYNOPSIS
#include <dev/pckbport/pckbportvar.h>
pckbport_tag_t
pckbport_attach(void *, struct pckbport_accessops const *);
struct device *
pckbport_attach_slot(struct device *, pckbport_tag_t, pckbport_slot_t);
int
pckbport_cnattach(void *, struct pckbport_accessops const *,
pckbport_slot_t);
void
pckbportintr(pckbport_tag_t, pckbport_slot_t, int);
void
pckbport_set_inputhandler(pckbport_tag_t, pckbport_slot_t,
pckbport_inputfcn, void *, char *);
void
pckbport_flush(pckbport_tag_t, pckbport_slot_t);
int
pckbport_poll_cmd(pckbport_tag_t, pckbport_slot_t, u_char *, int, int,
u_char *, int);
int
pckbport_enqueue_cmd(pckbport_tag_t, pckbport_slot_t, u_char *, int, int,
int, u_char *);
int
pckbport_poll_data(pckbport_tag_t, pckbport_slot_t);
void
pckbport_set_poll(pckbport_tag_t, pckbport_slot_t, int);
int
pckbport_xt_translation(pckbport_tag_t, pckbport_slot_t, int);
void
pckbport_slot_enable(pckbport_tag_t, pckbport_slot_t, int);
DESCRIPTION
The machine-independent pckbport subsystem provides an interface layer
corresponding to the serial keyboard and mouse interface used on the IBM
PS/2 and many other machines. It interfaces a controller driver such as
pckbc(4) to device drivers such as pckbd(4) and pms(4).
A single controller can have up to two ports (known as "slots"), and
these are identified by values of type pckbport_slot_t. The values
PCKBPORT_KBD_SLOT and PCKBPORT_AUX_SLOT should be used for keyboard and
mouse ports respectively. Each controller is identified by an opaque
value of type pckbport_tag_t.
Controller interface
A PC keyboard controller registers itself by calling
pckbport_attach(cookie, ops), with ops being a pointer to a struct
pckbport_accessops containing pointers to functions for driving the
controller, which will all be called with cookie as their first argument.
pckbport_attach() returns the pckbport_tag_t assigned to the controller.
The controller is then expected to call pckbport_attach_slot() for each
slot with which it is equipped, passing the struct device * corresponding
to the controller. This function returns a pointer to the child device
attached to the slot, or NULL if no such device was attached.
The elements of struct pckbport_accessops each take as their first two
arguments the cookie passed to pckbport_attach() and the slot in
question. The elements are:
int (*t_xt_translation)(void *cookie, pckbport_slot_t slot, int on)
If on is non-zero, enable, otherwise disable, AT-to-XT
keycode translation on the slot specified. Returns 1
on success, 0 on failure (or if the controller does not
support such translation).
int (*t_send_devcmd)(void *cookie, pckbport_slot_t slot, u_char byte)
Send a single byte to the device without waiting for
completion. Returns 1 on success, 0 on failure.
int (*t_poll_data1)(void *cookie, pckbport_slot_t slot)
Wait for and return one byte of data from the device,
without using interrupts. This function will only be
called after (*t_set_poll)() has been used to put the
slot in polling mode. If no data are forthcoming from
the device after about 100ms, return -1.
void (*t_slot_enable)(void *cookie, pckbport_slot_t slot, int on)
If on is non-zero, enable, otherwise disable, the slot.
If a slot is disabled, it can be powered down, and is
not expected to generate any interrupts. When first
attached, ports should be disabled.
void (*t_intr_establish)(void *cookie, pckbport_slot_t slot)
Set up an interrupt handler for the slot. Called when
a device gets attached to it.
void (*t_set_poll)(void *cookie, pckbport_slot_t slot, int on)
If on is non-zero, enable, otherwise disable, polling
mode on the slot. In polling mode, data received from
the device are provided to (*t_poll_data1)() and not
passed to pckbportintr(), whether or not interrupts are
enabled. In non-polling mode, data from the device are
expected to cause interrupts. The controller interrupt
handler should call pckbportintr(tag, slot, byte) once
for each byte received from the device. When first
attached, a port should be in non-polling mode.
Device interface
Devices that attach to pckbport controllers do so using the normal
autoconf(9) mechanism. Their (*ca_match)() and (*ca_attach)() functions
get passed a struct pckbport_attach_args which contains the controller
and slot number where the device was found. Device drivers can use the
following functions to communicate with the controller. Each takes tag
and slot arguments to specify the slot to be acted on.
pckbport_set_inputhandler(tag, slot, fn, arg, name)
Arrange for fn to be called with argument arg whenever
an unsolicited byte is received from the slot. The
function will be called at spltty().
pckbport_flush(tag, slot)
Ensure that there is no pending input from the slot.
pckbport_poll_cmd(tag, slot, cmd, len, responselen, respbuf, slow)
Issue a complete device command, cmd, len bytes long,
expecting a response responselen bytes long, which will
be placed in respbuf. If slow is true, the command is
expected to take over a second to execute.
pckbport_poll_cmd() handles getting an acknowledgement
from the device and retrying the command if necessary.
Returns 0 on success, and an error value on failure.
This function should only be called during
autoconfiguration or when the slot has been placed into
polling mode by pckbport_set_poll().
pckbport_enqueue_cmd(tag, slot, cmd, len, responselen, sync, respbuf)
Issue a complete device command, cmd, len bytes long,
expecting a response responselen bytes long, which will
be places in respbuf. If sync is true,
pckbport_enqueue_cmd() waits for the command to
complete before returning, otherwise it returns
immediately. It is not safe to set sync when calling
from an interrupt context. The pckbport layer handles
getting an acknowledgement from the device and retrying
the command if necessary. Returns 0 on success, and an
error value on failure.
pckbport_poll_data(tag, slot)
Low-level command to poll for a single byte of data
from the device, but ignoring bytes that are part of
the response to a command issued through
pckbport_enqueue_command().
pckbport_set_poll(tag, slot, on)
If on is true, enable polling on the slot, otherwise
disable it. In polling mode, pckbport_poll_cmd() can
be used to issue commands and pckbport_poll_data() to
read unsolicited data, without enabling interrupts. In
non-polling mode, commands should be issued using
pckbport_enqueue_cmd(), unsolicited data are handled by
the input function, and disabling interrupts will
suspend pckbport operation.
pckbport_xt_translation(tag, slot, on)
Passthrough of (*t_xt_translation)() (see above).
pckbport_slot(enable, tag, slot, on)
Passthrough of (*t_slot_enable)() (see above).
Console interface
On systems that can attach consoles through pckbport, the controller's
console attachment function (called very early in autoconfiguration)
calls pckbport_cnattach(cookie, ops, slot). The first two arguments are
the same as for pckbport_attach(), while the third indicates which slot
the console keyboard is attached to. pckbport_cnattach() either calls
pckbd_cnattach(), if it is available, or pckbport_machdep_cnattach().
The latter allows machine-dependent keyboard drivers to attach
themselves, but it is only called if a device with the
`pckbport_machdep_cnattach' attribute is configured into the system.
pckbport_cnattach() returns 0 on success and an error value on failure.
pckbport_machdep_cnattach() is expected to do the same.
CODE REFERENCES
The pckbport code, and the pckbd(4) and pms(4) device drivers are in
sys/dev/pckbport.
SEE ALSO
pckbc(4), pckbd(4), pms(4), autoconf(9), spl(9)
HISTORY
The pckbport system appeared in NetBSD 2.0. Before that, pckbd(4) and
pms(4) attached directly to pckbc(4) without any sensible way of using a
different controller.
NetBSD 10.99 August 5, 2004 NetBSD 10.99