xref: /freebsd/share/man/man4/psm.4 (revision 6e8394b8baa7d5d9153ab90de6824bcd19b3b4e1)
1.\"
2.\" Copyright (c) 1997
3.\" Kazutaka YOKOTA <yokota@zodiac.mech.utsunomiya-u.ac.jp>
4.\" All rights reserved.
5.\"
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7.\" modification, are permitted provided that the following conditions
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27.\" $Id: psm.4,v 1.15 1999/02/07 05:40:14 yokota Exp $
28.\"
29.Dd January 30, 1999
30.Dt PSM 4 i386
31.Os FreeBSD
32.Sh NAME
33.Nm psm
34.Nd
35PS/2 mouse style pointing device driver
36.Sh SYNOPSIS
37.Cd "options" \&"PSM_HOOKAPM\&"
38.Cd "options" \&"PSM_RESETAFTERSUSPEND\&"
39.Cd "options" \&"KBD_RESETDELAY=N\&"
40.Cd "options" \&"KBD_MAXWAIT=N\&"
41.Cd "options" \&"PSM_DEBUG=N\&"
42.Cd "options" \&"KBDIO_DEBUG=N\&"
43.Cd "device psm0 at atkbdc? irq 12"
44.Sh DESCRIPTION
45The
46.Nm
47driver provides support for the PS/2 mouse style pointing device.
48Currently there can be only one
49.Nm
50device node in the system.
51As the PS/2 mouse port is located
52at the auxiliary port of the keyboard controller,
53the keyboard controller driver,
54.Nm atkbdc ,
55must also be configured in the kernel.
56Note that there is currently no provision of changing the
57.Em irq
58number.
59.Pp
60Basic PS/2 style pointing device has two or three buttons.
61Some devices may have a roller or a wheel and/or additional buttons.
62.Ss Device Resolution
63The PS/2 style pointing device usually has several grades of resolution,
64that is, sensitivity of movement. They are typically 25, 50, 100 and 200
65pulse per inch. Some devices may have finer resolution.
66The current resolution can be changed at runtime. The
67.Nm
68driver allows the user to initially set the resolution
69via the driver flag
70.Pq see Sx DRIVER CONFIGURATION
71or change it later via the
72.Xr ioctl 2
73command
74.Dv MOUSE_SETMODE
75.Pq see Sx IOCTLS .
76.Ss Report Rate
77Frequency, or report rate, at which the device sends movement
78and button state reports to the host system is also configurable.
79The PS/2 style pointing device typically supports 10, 20, 40, 60, 80, 100
80and 200 reports per second.
8160 or 100 appears to be the default value for many devices.
82Note that when there is no movement and no button has changed its state,
83the device won't send anything to the host system.
84The report rate can be changed via an ioctl call.
85.Ss Operation Levels
86The
87.Nm
88driver has three levels of operation.
89The current operation level can be set via an ioctl call.
90.Pp
91At the level zero the basic support is provided; the device driver will report
92horizontal and vertical movement of the attached device
93and state of up to three buttons.
94The movement and status are encoded in a series of fixed-length data packets
95.Pq see Sx Data Packet Format .
96This is the default level of operation and the driver is initially
97at this level when opened by the user program.
98.Pp
99The operation level one, the `extended' level, supports a roller (or wheel),
100if any, and up to 11 buttons.
101The movement of the roller is reported as movement along the Z axis.
1028 byte data packets are sent to the user program at this level.
103.Pp
104At the operation level two, data from the pointing device is passed to the
105user program as is.
106Modern PS/2 type pointing devices often use proprietary data format.
107Therefore, the user program is expected to have
108intimate knowledge about the format from a particular device when operating
109the driver at this level.
110This level is called `native' level.
111.Ss Data Packet Format
112Data packets read from the
113.Nm
114driver are formatted differently at each operation level.
115.Pp
116A data packet from the PS/2 mouse style pointing device
117is three bytes long at the operation level zero:
118.Pp
119.Bl -tag -width Byte_1 -compact
120.It Byte 1
121.Bl -tag -width bit_7 -compact
122.It bit 7
123One indicates overflow in the vertical movement count.
124.It bit 6
125One indicates overflow in the horizontal movement count.
126.It bit 5
127Set if the vertical movement count is negative.
128.It bit 4
129Set if the horizontal movement count is negative.
130.It bit 3
131Always one.
132.\" The ALPS GlidePoint clears this bit when the user `taps' the surface of
133.\" the pad, otherwise the bit is set.
134.\" Most, if not all, other devices always set this bit.
135.It bit 2
136Middle button status; set if pressed. For devices without the middle
137button, this bit is always zero.
138.It bit 1
139Right button status; set if pressed.
140.It bit 0
141Left button status; set if pressed.
142.El
143.It Byte 2
144Horizontal movement count in two's compliment;
145-256 through 255.
146Note that the sign bit is in the first byte.
147.It Byte 3
148Vertical movement count in two's compliment;
149-256 through 255.
150Note that the sign bit is in the first byte.
151.El
152.Pp
153At the level one, a data packet is encoded
154in the standard format
155.Dv MOUSE_PROTO_SYSMOUSE
156as defined in
157.Xr mouse 4 .
158.Pp
159At the level two, native level, there is no standard on the size and format
160of the data packet.
161.Ss Acceleration
162The
163.Nm
164driver can somewhat `accelerate' the movement of the pointing device.
165The faster you move the device, the further the pointer
166travels on the screen.
167The driver has an internal variable which governs the effect of
168the acceleration. Its value can be modified via the driver flag
169or via an ioctl call.
170.Ss Device Number
171The minor device number of the
172.Nm
173is made up of:
174.Bd -literal -offset indent
175minor = (`unit' << 1) | `non-blocking'
176.Ed
177.Pp
178where `unit' is the device number (usually 0) and the `non-blocking' bit
179is set to indicate ``don't block waiting for mouse input,
180return immediately''.
181The `non-blocking' bit should be set for \fIXFree86\fP,
182therefore the minor device number usually used for \fIXFree86\fP is 1.
183See
184.Sx FILES
185for device node names.
186.Sh DRIVER CONFIGURATION
187.Ss Kernel Configuration Options
188There are following kernel configuration options to control the
189.Nm
190driver.
191They may be set in the kernel configuration file
192.Pq see Xr config 8 .
193.Bl -tag -width MOUSE
194.It Em PSM_HOOKAPM
195The built-in PS/2 pointing device of some laptop computers is somehow
196not operable immediately after the system `resumes' from
197the power saving mode,
198though it will eventually become available.
199There are reports that
200stimulating the device by performing I/O will help
201waking up the device quickly. This option will add a piece of code
202to the
203.Nm
204driver to hook
205the APM `resume' event and exercise some harmless I/O operations to the
206device.
207.It Em PSM_RESETAFTERSUSPEND
208This option adds more drastic action for the above problem.
209It will make the
210.Nm
211driver to reset the pointing device after the APM resume event.
212It has no effect unless the
213.Em PSM_HOOKAPM
214option is enabled as well.
215.It Em KBD_RESETDELAY=X, KBD_MAXWAIT=Y
216The
217.Nm
218driver will attempt to reset the pointing device during the boot process.
219It sometimes takes a long while before the device will respond after
220reset. These options control how long the driver should wait before
221it eventually gives up waiting. The driver will wait
222.Fa X
223*
224.Fa Y
225msecs at most. If the driver seems unable to detect your pointing
226device, you may want to increase these values. The default values are
227200 msec for
228.Fa X
229and 5
230for
231.Fa Y .
232.It Em PSM_DEBUG=N, KBDIO_DEBUG=N
233Sets the debug level to
234.Fa N .
235The default debug level is zero. See
236.Sx DIAGNOSTICS
237for debug logging.
238.El
239.Ss Driver Flags
240The
241.Nm
242driver accepts the following driver flags. Set them in the
243kernel configuration file or in the User Configuration Menu at
244the boot time
245.Pq see Xr boot 8 .
246.Pp
247.Bl -tag -width MOUSE
248.It bit 0..3 RESOLUTION
249This flag specifies the resolution of the pointing device.
250It must be zero through four. The greater the value
251is, the finer resolution the device will select.
252Actual resolution selected by this field varies according to the model
253of the device. Typical resolutions are:
254.Pp
255.Bl -tag -width 0_(medium_high)__ -compact
256.It Em 1 (low)
25725 pulse per inch (ppi)
258.It Em 2 (medium low)
25950 ppi
260.It Em 3 (medium high)
261100 ppi
262.It Em 4 (high)
263200 ppi
264.El
265.Pp
266Leaving this flag zero will selects the default resolution for the
267device (whatever it is).
268.It bit 4..7 ACCELERATION
269This flag controls the amount of acceleration effect.
270The smaller the value of this flag is, more sensitive the movement becomes.
271The minimum value allowed, thus the value for the most sensitive setting,
272is one. Setting this flag to zero will completely disables the
273acceleration effect.
274.It bit 8 NOCHECKSYNC
275The
276.Nm
277driver tries to detect the first byte of the data packet by checking
278the bit pattern of that byte. Although this method should work with most
279PS/2 pointing devices, it may interfere with some devices which are not
280so compatible with known devices.
281If you think your pointing device is not functioning as expected,
282and the kernel frequently prints the following message to the console,
283.Bd -literal -offset indent
284psmintr: out of sync (xxxx != yyyy).
285.Ed
286.Pp
287set this flag to disable synchronization check and see if it helps.
288.It bit 9 NOIDPROBE
289The
290.Nm
291driver will not try to identify the model of the pointing device and
292will not carry out model-specific initialization.
293The device should always act like a standard PS/2 mouse without such
294initialization.
295Extra features, such as wheels and additional buttons, won't be
296recognized by the
297.Nm
298driver.
299.It bit 10 NORESET
300When this flag is set, the
301.Nm
302driver won't reset the pointing device when initializing the device.
303If the FreeBSD kernel
304is started after another OS has run, the pointing device will inherit
305settings from the previous OS.
306However, because there is no way for the
307.Nm
308driver to know the settings, the device and the driver may not
309work correctly.
310The flag should never be necessary under normal circumstances.
311.It bit 11 FORCETAP
312Some pad devices report as if the fourth button is pressed
313when the user `taps' the surface of the device (see
314.Sx CAVEATS ) .
315This flag will make the
316.Nm
317driver assume that the device behaves this way.
318Without the flag, the driver will assume this behavior
319for ALPS GlidePoint models only.
320.It bit 12 IGNOREPORTERROR
321This flag makes
322.Nm
323driver ignore certain error conditions when probing the PS/2 mouse port.
324It should never be necessary under normal circumstances.
325.El
326.Sh IOCTLS
327There are a few
328.Xr ioctl 2
329commands for mouse drivers.
330These commands and related structures and constants are defined in
331.Ao Pa machine/mouse.h Ac .
332General description of the commands is given in
333.Xr mouse 4 .
334This section explains the features specific to the
335.Nm
336driver.
337.Pp
338.Bl -tag -width MOUSE -compact
339.It Dv MOUSE_GETLEVEL Ar int *level
340.It Dv MOUSE_SETLEVEL Ar int *level
341These commands manipulate the operation level of the
342.Nm
343driver.
344.Pp
345.It Dv MOUSE_GETHWINFO Ar mousehw_t *hw
346Returns the hardware information of the attached device in the following
347structure.
348.Bd -literal
349typedef struct mousehw {
350    int buttons;    /* number of buttons */
351    int iftype;     /* I/F type */
352    int type;       /* mouse/track ball/pad... */
353    int model;      /* I/F dependent model ID */
354    int hwid;       /* I/F dependent hardware ID */
355} mousehw_t;
356.Ed
357.Pp
358The
359.Dv buttons
360field holds the number of buttons on the device.
361The
362.Nm
363driver currently can detect the 3 button mouse from Logitech and report
364accordingly.
365The 3 button mouse from the other manufacturer may or may not be
366reported correctly. However, it will not affect the operation of
367the driver.
368.Pp
369The
370.Dv iftype
371is always
372.Dv MOUSE_IF_PS2 .
373.Pp
374The
375.Dv type
376tells the device type:
377.Dv MOUSE_MOUSE ,
378.Dv MOUSE_TRACKBALL ,
379.Dv MOUSE_STICK ,
380.Dv MOUSE_PAD ,
381or
382.Dv MOUSE_UNKNOWN .
383The user should not heavily rely on this field, as the
384driver may not always, in fact it is very rarely able to, identify
385the device type.
386.Pp
387The
388.Dv model
389is always
390.Dv MOUSE_MODEL_GENERIC
391at the operation level 0.
392It may be
393.Dv MOUSE_MODEL_GENERIC
394or one of
395.Dv MOUSE_MODEL_XXX
396constants at higher operation levels.
397Again the
398.Nm
399driver may or may not set an appropriate value in this field.
400.Pp
401The
402.Dv hwid
403is the ID value returned by the device.
404Known IDs include:
405.Pp
406.Bl -tag -width 0__ -compact
407.It Em 0
408Mouse (Microsoft, Logitech and many other manufacturers)
409.It Em 2
410Microsoft Ballpoint mouse
411.It Em 3
412Microsoft IntelliMouse
413.El
414.Pp
415.It Dv MOUSE_GETMODE Ar mousemode_t *mode
416The command gets the current operation parameters of the mouse
417driver.
418.Bd -literal
419typedef struct mousemode {
420    int protocol;    /* MOUSE_PROTO_XXX */
421    int rate;        /* report rate (per sec), -1 if unknown */
422    int resolution;  /* MOUSE_RES_XXX, -1 if unknown */
423    int accelfactor; /* acceleration factor */
424    int level;       /* driver operation level */
425    int packetsize;  /* the length of the data packet */
426    unsigned char syncmask[2]; /* sync. bits */
427} mousemode_t;
428.Ed
429.Pp
430The
431.Dv protocol
432is
433.Dv MOUSE_PROTO_PS2
434at the operation level zero and two.
435.Dv MOUSE_PROTO_SYSMOUSE
436at the operation level one.
437.Pp
438The
439.Dv rate
440is the status report rate (reports/sec) at which the device will send
441movement report to the host computer.
442Typical supported values are 10, 20, 40, 60, 80, 100 and 200.
443Some mice may accept other arbitrary values too.
444.Pp
445The
446.Dv resolution
447of the pointing device must be one of
448.Dv MOUSE_RES_XXX
449constants or a positive value. The greater the value
450is, the finer resolution the mouse will select.
451Actual resolution selected by the
452.Dv MOUSE_RES_XXX
453constant varies according to the model of mouse. Typical resolutions are:
454.Pp
455.Bl -tag -width MOUSE_RES_MEDIUMHIGH__ -compact
456.It Dv MOUSE_RES_LOW
45725 ppi
458.It Dv MOUSE_RES_MEDIUMLOW
45950 ppi
460.It Dv MOUSE_RES_MEDIUMHIGH
461100 ppi
462.It Dv MOUSE_RES_HIGH
463200 ppi
464.El
465.Pp
466The
467.Dv accelfactor
468field holds a value to control acceleration feature
469.Pq see Sx Acceleration .
470It must be zero or greater.  If it is zero, acceleration is disabled.
471.Pp
472The
473.Dv packetsize
474field specifies the length of the data packet. It depends on the
475operation level and the model of the pointing device.
476.Pp
477.Bl -tag -width level_0__ -compact
478.It Em level 0
4793 bytes
480.It Em level 1
4818 bytes
482.It Em level 2
483Depends on the model of the device
484.El
485.Pp
486The array
487.Dv syncmask
488holds a bit mask and pattern to detect the first byte of the
489data packet.
490.Dv syncmask[0]
491is the bit mask to be ANDed with a byte. If the result is equal to
492.Dv syncmask[1] ,
493the byte is likely to be the first byte of the data packet.
494Note that this detection method is not 100% reliable,
495thus, should be taken only as an advisory measure.
496.Pp
497.It Dv MOUSE_SETMODE Ar mousemode_t *mode
498The command changes the current operation parameters of the mouse driver
499as specified in
500.Ar mode .
501Only
502.Dv rate ,
503.Dv resolution ,
504.Dv level
505and
506.Dv accelfactor
507may be modifiable. Setting values in the other field does not generate
508error and has no effect.
509.Pp
510If you do not want to change the current setting of a field, put -1
511there.
512You may also put zero in
513.Dv resolution
514and
515.Dv rate ,
516and the default value for the fields will be selected.
517.\" .Pp
518.\" .It Dv MOUSE_GETVARS Ar mousevar_t *vars
519.\" .It Dv MOUSE_SETVARS Ar mousevar_t *vars
520.\" These commands are not supported by the
521.\" .Nm
522.\" driver.
523.Pp
524.It Dv MOUSE_READDATA Ar mousedata_t *data
525.\" The command reads the raw data from the device.
526.\" .Bd -literal
527.\" typedef struct mousedata {
528.\"     int len;        /* # of data in the buffer */
529.\"     int buf[16];    /* data buffer */
530.\" } mousedata_t;
531.\" .Ed
532.\" .Pp
533.\" Upon returning to the user program, the driver will place the number
534.\" of valid data bytes in the buffer in the
535.\" .Dv len
536.\" field.
537.\" .Pp
538.It Dv MOUSE_READSTATE Ar mousedata_t *state
539.\" The command reads the hardware settings from the device.
540.\" Upon returning to the user program, the driver will place the number
541.\" of valid data bytes in the buffer in the
542.\" .Dv len
543.\" field. It is usually 3 bytes.
544.\" The buffer is formatted as follows:
545.\" .Pp
546.\" .Bl -tag -width Byte_1 -compact
547.\" .It Byte 1
548.\" .Bl -tag -width bit_6 -compact
549.\" .It bit 7
550.\" Reserved.
551.\" .It bit 6
552.\" 0 - stream mode, 1 - remote mode.
553.\" In the stream mode, the pointing device sends the device status
554.\" whenever its state changes. In the remote mode, the host computer
555.\" must request the status to be sent.
556.\" The
557.\" .Nm
558.\" driver puts the device in the stream mode.
559.\" .It bit 5
560.\" Set if the pointing device is currently enabled. Otherwise zero.
561.\" .It bit 4
562.\" 0 - 1:1 scaling, 1 - 2:1 scaling.
563.\" 1:1 scaling is the default.
564.\" .It bit 3
565.\" Reserved.
566.\" .It bit 2
567.\" Left button status; set if pressed.
568.\" .It bit 1
569.\" Middle button status; set if pressed.
570.\" .It bit 0
571.\" Right button status; set if pressed.
572.\" .El
573.\" .It Byte 2
574.\" .Bl -tag -width bit_6_0 -compact
575.\" .It bit 7
576.\" Reserved.
577.\" .It bit 6..0
578.\" Resolution code: zero through three. Actual resolution for
579.\" the resolution code varies from one device to another.
580.\" .El
581.\" .It Byte 3
582.\" The status report rate (reports/sec) at which the device will send
583.\" movement report to the host computer.
584.\" .El
585These commands are not currently supported by the
586.Nm
587driver.
588.Pp
589.It Dv MOUSE_GETSTATE Ar mousestatus_t *status
590The command returns the current state of buttons and
591movement counts as described in
592.Xr mouse 4 .
593.El
594.Sh FILES
595.Bl -tag -width /dev/npsm0 -compact
596.It Pa /dev/psm0
597`non-blocking' device node
598.It Pa /dev/bpsm0
599`blocking' device node under
600.Em devfs .
601.El
602.Sh EXAMPLE
603.Dl "options" \&"PSM_HOOKAPM\&"
604.Dl "device psm0 at atkbdc? irq 12"
605.Pp
606Add the
607.Nm
608driver to the kernel with the optional code to stimulate the pointing device
609after the `resume' event.
610.Pp
611.Dl "device psm0 at atkbdc? flags 0x024 irq 12"
612.Pp
613Set the device resolution high (4) and the acceleration factor to 2.
614.Sh DIAGNOSTICS
615.Pp
616At debug level 0, little information is logged except for the following
617line during boot process:
618.Bd -literal -offset indent
619psm0: device ID X
620.Ed
621.Pp
622where
623.Fa X
624the device ID code returned by the found pointing device.
625See
626.Dv MOUSE_GETINFO
627for known IDs.
628.Pp
629At debug level 1 more information will be logged
630while the driver probes the auxiliary port (mouse port).
631Messages are logged with the LOG_KERN facility at the LOG_DEBUG level
632.Pq see Xr syslogd 8 .
633.Bd -literal -offset indent
634psm0: current command byte:xxxx
635kbdio: TEST_AUX_PORT status:0000
636kbdio: RESET_AUX return code:00fa
637kbdio: RESET_AUX status:00aa
638kbdio: RESET_AUX ID:0000
639[...]
640psm: status 00 02 64
641psm0 irq 12 on isa
642psm0: model AAAA, device ID X, N buttons
643psm0: config:00000www, flags:0000uuuu, packet size:M
644psm0: syncmask:xx, syncbits:yy
645.Ed
646.Pp
647The first line shows the command byte value of the keyboard
648controller just before the auxiliary port is probed.
649It usually is 4D, 45, 47 or 65, depending on how the motherboard BIOS
650initialized the keyboard controller upon power-up.
651.Pp
652The second line shows the result of the keyboard controller's
653test on the auxiliary port interface, with zero indicating
654no error; note that some controllers report no error even if
655the port does not exist in the system, however.
656.Pp
657The third through fifth lines show the reset status of the pointing device.
658The functioning device should return the sequence of FA AA <ID>.
659The ID code is described above.
660.Pp
661The seventh line shows the current hardware settings.
662.\" See
663.\" .Dv MOUSE_READSTATE
664.\" for definitions.
665These bytes are formatted as follows:
666.Pp
667.Bl -tag -width Byte_1 -compact
668.It Byte 1
669.Bl -tag -width bit_6 -compact
670.It bit 7
671Reserved.
672.It bit 6
6730 - stream mode, 1 - remote mode.
674In the stream mode, the pointing device sends the device status
675whenever its state changes. In the remote mode, the host computer
676must request the status to be sent.
677The
678.Nm
679driver puts the device in the stream mode.
680.It bit 5
681Set if the pointing device is currently enabled. Otherwise zero.
682.It bit 4
6830 - 1:1 scaling, 1 - 2:1 scaling.
6841:1 scaling is the default.
685.It bit 3
686Reserved.
687.It bit 2
688Left button status; set if pressed.
689.It bit 1
690Middle button status; set if pressed.
691.It bit 0
692Right button status; set if pressed.
693.El
694.It Byte 2
695.Bl -tag -width bit_6_0 -compact
696.It bit 7
697Reserved.
698.It bit 6..0
699Resolution code: zero through three. Actual resolution for
700the resolution code varies from one device to another.
701.El
702.It Byte 3
703The status report rate (reports/sec) at which the device will send
704movement report to the host computer.
705.El
706.Pp
707Note that the pointing device will not be enabled until the
708.Nm
709driver is opened by the user program.
710.Pp
711The rest of the lines show the device ID code, the number of detected
712buttons and internal variables.
713.Pp
714At debug level 2, much more detailed information is logged.
715.Sh CAVEATS
716Many pad devices behave as if the first (left) button were pressed if
717the user `taps' the surface of the pad.
718In contrast, some ALPS GlidePoint pad models treat the tapping action
719as fourth button events.
720.Pp
721Some PS/2 mouse models from MouseSystems require to be put in the
722high resolution mode to work properly. Use the driver flag to
723set resolution.
724.Pp
725There is not a guaranteed way to re-synchronize with the first byte
726of the packet once we are out of synchronization with the data
727stream. However, if you are using the \fIXFree86\fP server and experiencing
728the problem, you may be able to make the X server synchronize with the mouse
729by switching away to a virtual terminal and getting back to the X server,
730unless the X server is accessing the mouse via
731.Xr moused 1 .
732Clicking any button without moving the mouse may also work.
733.Sh BUGS
734The ioctl command
735.Dv MOUSEIOCREAD
736has been removed. It was never functional anyway.
737.Sh SEE ALSO
738.Xr ioctl 2 ,
739.Xr syslog 3 ,
740.Xr atkbdc 4 ,
741.Xr mouse 4 ,
742.Xr mse 4 ,
743.Xr sysmouse 4 ,
744.Xr moused 8 ,
745.Xr syslogd 8
746.\".Sh HISTORY
747.Sh AUTHORS
748The
749.Nm
750driver is based on the work done by quite a number of people, including
751.An Eric Forsberg ,
752.An Sandi Donno ,
753.An Rick Macklem ,
754.An Andrew Herbert ,
755.An Charles Hannum ,
756.An Shoji Yuen
757and
758.An Kazutaka Yokota
759to name the few.
760.Pp
761This manual page was written by
762.An Kazutaka Yokota Aq yokota@FreeBSD.org .
763