2015-07-25 18:14:35 +00:00
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.\" Copyright (c) 2015 Michael Gmelin <freebsd@grem.de>
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.\" All rights reserved.
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.\"
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.\" Redistribution and use in source and binary forms, with or without
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.\" modification, are permitted provided that the following conditions
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.\" are met:
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.\" 1. Redistributions of source code must retain the above copyright
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.\" notice, this list of conditions and the following disclaimer.
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.\" 2. Redistributions in binary form must reproduce the above copyright
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.\" notice, this list of conditions and the following disclaimer in the
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.\" documentation and/or other materials provided with the distribution.
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.\"
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.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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.\" SUCH DAMAGE.
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.\"
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.\" $FreeBSD$
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.\"
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2018-12-18 21:43:33 +00:00
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.Dd December 18, 2018
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2015-07-25 18:14:35 +00:00
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.Dt CYAPA 4
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.Os
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.Sh NAME
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.Nm cyapa
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.Nd Cypress APA trackpad with I2C interface driver
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.Sh SYNOPSIS
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To compile this driver into the kernel, place the following lines into
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the kernel configuration file:
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.Bd -ragged -offset indent
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.Cd "device cyapa"
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.Cd "device ig4"
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add iic interface to ig4 driver, move isl and cyapa to iicbus
Summary:
The hardware does not expose a classic SMBus interface.
Instead it has a lower level interface that can express a far richer
I2C protocol than what smbus offers. However, the interface does not
provide a way to explicitly generate the I2C stop and start conditions.
It's only possible to request that the stop condition is generated
after transferring the next byte in either direction. So, at least
one data byte must always be transferred.
Thus, some I2C sequences are impossible to generate, e.g., an equivalent
of smbus quick command (<start>-<slave addr>-<r/w bit>-<stop>).
At the same time isl(4) and cyapa(4) are moved to iicbus and now they use
iicbus_transfer for communication. Previously they used smbus_trans()
interface that is not defined by the SMBus protocol and was implemented
only by ig4(4). In fact, that interface was impossible to implement
for the typical SMBus controllers like intpm(4) or ichsmb(4) where
a type of the SMBus command must be programmed.
The plan is to remove smbus_trans() and all its uses.
As an aside, the smbus_trans() method deviates from the standard,
but perhaps backwards, FreeBSD convention of using 8-bit slave
addresses (shifted by 1 bit to the left). The method expects
7-bit addresses.
There is a user facing consequence of this change.
A user must now provide device hints for isl and cyapa that specify an iicbus to use
and a slave address on it.
On Chromebook hardware where isl and cyapa devices are commonly found
it is also possible to use a new chromebook_platform(4) driver that
automatically configures isl and cyapa devices. There is no need to
provide the device hints in that case,
Right now smbus(4) driver tries to discover all slaves on the bus.
That is very dangerous. Fortunately, the probing code uses smbus_trans()
to do its job, so it is really enabled for ig4 only.
The plan is to remove that auto-probing code and smbus_trans().
Tested by: grembo, Matthias Apitz <guru@unixarea.de> (w/o
chromebook_platform)
Discussed with: grembo, imp
Reviewed by: wblock (docs)
MFC after: 1 month
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D8172
2016-10-30 12:15:33 +00:00
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.Cd "device iicbus"
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2015-07-25 18:14:35 +00:00
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.Ed
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.Pp
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Alternatively, to load the driver as a module at boot time, place the following line in
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.Xr loader.conf 5 :
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.Bd -literal -offset indent
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cyapa_load="YES"
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ig4_load="YES"
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.Ed
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add iic interface to ig4 driver, move isl and cyapa to iicbus
Summary:
The hardware does not expose a classic SMBus interface.
Instead it has a lower level interface that can express a far richer
I2C protocol than what smbus offers. However, the interface does not
provide a way to explicitly generate the I2C stop and start conditions.
It's only possible to request that the stop condition is generated
after transferring the next byte in either direction. So, at least
one data byte must always be transferred.
Thus, some I2C sequences are impossible to generate, e.g., an equivalent
of smbus quick command (<start>-<slave addr>-<r/w bit>-<stop>).
At the same time isl(4) and cyapa(4) are moved to iicbus and now they use
iicbus_transfer for communication. Previously they used smbus_trans()
interface that is not defined by the SMBus protocol and was implemented
only by ig4(4). In fact, that interface was impossible to implement
for the typical SMBus controllers like intpm(4) or ichsmb(4) where
a type of the SMBus command must be programmed.
The plan is to remove smbus_trans() and all its uses.
As an aside, the smbus_trans() method deviates from the standard,
but perhaps backwards, FreeBSD convention of using 8-bit slave
addresses (shifted by 1 bit to the left). The method expects
7-bit addresses.
There is a user facing consequence of this change.
A user must now provide device hints for isl and cyapa that specify an iicbus to use
and a slave address on it.
On Chromebook hardware where isl and cyapa devices are commonly found
it is also possible to use a new chromebook_platform(4) driver that
automatically configures isl and cyapa devices. There is no need to
provide the device hints in that case,
Right now smbus(4) driver tries to discover all slaves on the bus.
That is very dangerous. Fortunately, the probing code uses smbus_trans()
to do its job, so it is really enabled for ig4 only.
The plan is to remove that auto-probing code and smbus_trans().
Tested by: grembo, Matthias Apitz <guru@unixarea.de> (w/o
chromebook_platform)
Discussed with: grembo, imp
Reviewed by: wblock (docs)
MFC after: 1 month
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D8172
2016-10-30 12:15:33 +00:00
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.Pp
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2018-12-18 21:43:33 +00:00
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On many Chromebook models this driver can be automatically configured with the
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help of the
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.Xr chromebook_platform 4
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driver.
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Alternatively, the
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.Nm
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driver can be manually configured in
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add iic interface to ig4 driver, move isl and cyapa to iicbus
Summary:
The hardware does not expose a classic SMBus interface.
Instead it has a lower level interface that can express a far richer
I2C protocol than what smbus offers. However, the interface does not
provide a way to explicitly generate the I2C stop and start conditions.
It's only possible to request that the stop condition is generated
after transferring the next byte in either direction. So, at least
one data byte must always be transferred.
Thus, some I2C sequences are impossible to generate, e.g., an equivalent
of smbus quick command (<start>-<slave addr>-<r/w bit>-<stop>).
At the same time isl(4) and cyapa(4) are moved to iicbus and now they use
iicbus_transfer for communication. Previously they used smbus_trans()
interface that is not defined by the SMBus protocol and was implemented
only by ig4(4). In fact, that interface was impossible to implement
for the typical SMBus controllers like intpm(4) or ichsmb(4) where
a type of the SMBus command must be programmed.
The plan is to remove smbus_trans() and all its uses.
As an aside, the smbus_trans() method deviates from the standard,
but perhaps backwards, FreeBSD convention of using 8-bit slave
addresses (shifted by 1 bit to the left). The method expects
7-bit addresses.
There is a user facing consequence of this change.
A user must now provide device hints for isl and cyapa that specify an iicbus to use
and a slave address on it.
On Chromebook hardware where isl and cyapa devices are commonly found
it is also possible to use a new chromebook_platform(4) driver that
automatically configures isl and cyapa devices. There is no need to
provide the device hints in that case,
Right now smbus(4) driver tries to discover all slaves on the bus.
That is very dangerous. Fortunately, the probing code uses smbus_trans()
to do its job, so it is really enabled for ig4 only.
The plan is to remove that auto-probing code and smbus_trans().
Tested by: grembo, Matthias Apitz <guru@unixarea.de> (w/o
chromebook_platform)
Discussed with: grembo, imp
Reviewed by: wblock (docs)
MFC after: 1 month
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D8172
2016-10-30 12:15:33 +00:00
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.Pa /boot/device.hints :
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.Cd hint.cyapa.0.at="iicbus0"
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.Cd hint.cyapa.0.addr="0xCE"
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.Cd hint.cyapa.1.at="iicbus1"
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.Cd hint.cyapa.1.addr="0xCE"
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2015-07-25 18:14:35 +00:00
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.Sh DESCRIPTION
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The
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.Nm
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driver provides support for the Cypress APA trackpad.
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It emulates the IntelliMouse PS/2 protocol.
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It supports basic mouse ioctls, so that
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.Xr moused 8
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is supported properly.
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.Ss Trackpad layout
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.Bd -literal
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2/3 1/3
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+--------------------+------------+
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| | Middle |
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| | Button |
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| Left | |
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| Button +------------+
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| | Right |
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| | Button |
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+--------------------+............|
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| Thumb/Button Area | 15%
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+---------------------------------+
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.Ed
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.Ss Trackpad features
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.Bl -tag -width 8n
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.It Va Two finger scrolling
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Use two fingers for Z axis scrolling.
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.It Va Button down/second finger
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While one finger clicks and holds down the touchpad, the second finger can be
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used to move the mouse cursor.
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This can be useful for drawing or selecting text.
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.It Va Thumb/Button area
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The lower 15% of the trackpad will not affect the mouse cursor position.
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This allows for high precision clicking, by controlling the cursor with the
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index finger and pushing/holding the pad down with the thumb.
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.It Va Trackpad button
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Push physical button.
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The left two thirds of the pad issues a LEFT button event.
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The upper right corner issues a MIDDLE button event.
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The lower right corner issues a RIGHT button.
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Optionally, tap to click can be enabled (see below).
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.El
|
add iic interface to ig4 driver, move isl and cyapa to iicbus
Summary:
The hardware does not expose a classic SMBus interface.
Instead it has a lower level interface that can express a far richer
I2C protocol than what smbus offers. However, the interface does not
provide a way to explicitly generate the I2C stop and start conditions.
It's only possible to request that the stop condition is generated
after transferring the next byte in either direction. So, at least
one data byte must always be transferred.
Thus, some I2C sequences are impossible to generate, e.g., an equivalent
of smbus quick command (<start>-<slave addr>-<r/w bit>-<stop>).
At the same time isl(4) and cyapa(4) are moved to iicbus and now they use
iicbus_transfer for communication. Previously they used smbus_trans()
interface that is not defined by the SMBus protocol and was implemented
only by ig4(4). In fact, that interface was impossible to implement
for the typical SMBus controllers like intpm(4) or ichsmb(4) where
a type of the SMBus command must be programmed.
The plan is to remove smbus_trans() and all its uses.
As an aside, the smbus_trans() method deviates from the standard,
but perhaps backwards, FreeBSD convention of using 8-bit slave
addresses (shifted by 1 bit to the left). The method expects
7-bit addresses.
There is a user facing consequence of this change.
A user must now provide device hints for isl and cyapa that specify an iicbus to use
and a slave address on it.
On Chromebook hardware where isl and cyapa devices are commonly found
it is also possible to use a new chromebook_platform(4) driver that
automatically configures isl and cyapa devices. There is no need to
provide the device hints in that case,
Right now smbus(4) driver tries to discover all slaves on the bus.
That is very dangerous. Fortunately, the probing code uses smbus_trans()
to do its job, so it is really enabled for ig4 only.
The plan is to remove that auto-probing code and smbus_trans().
Tested by: grembo, Matthias Apitz <guru@unixarea.de> (w/o
chromebook_platform)
Discussed with: grembo, imp
Reviewed by: wblock (docs)
MFC after: 1 month
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D8172
2016-10-30 12:15:33 +00:00
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.Pp
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On a system using
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.Xr device.hints 5 ,
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these values are configurable for
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.Nm :
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.Bl -tag -width "hint.cyapa.%d.addr"
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.It Va hint.cyapa.%d.at
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target
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.Xr iicbus 4 .
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.It Va hint.cyapa.%d.addr
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.Nm
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i2c address on the
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.Xr iicbus 4 .
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.El
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2015-07-25 18:14:35 +00:00
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.Sh SYSCTL VARIABLES
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These
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.Xr sysctl 8
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variables are available:
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.Bl -tag -width 8n
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.It Va debug.cyapa_idle_freq
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Scan frequency in idle mode, the default is 1.
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.It Va debug.cyapa_slow_freq
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Scan frequency in slow mode, the default is 20.
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.It Va debug.cyapa_norm_freq
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Scan frequency in normal mode, the default is 100.
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.It Va debug.cyapa_minpressure
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Minimum pressure to detect a finger, the default is 12.
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.It Va debug.cyapa_enable_tapclick
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Controls tap to click.
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Possible values:
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.Bl -tag -width 8n
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.It 0
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Tap to click is disabled.
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This is the default value.
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.It 1
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Tap to click always generates a left mouse button event.
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.It 2
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Tap to click generates left mouse button event if the left 2/3rds of the pad
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are tapped and a right mouse button event otherwise.
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.It 3
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Tap to click generates mouse button events as if the physical button was
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pressed (see
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.Sx DESCRIPTION
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above).
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.El
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.It Va debug.cyapa_tapclick_min_ticks
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Minimum tap duration in ticks to create a click, the default is 1.
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.It Va debug.cyapa_tapclick_max_ticks
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Maximum tap duration in ticks to create a click, the default is 8.
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.It Va debug.cyapa_move_min_ticks
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Minimum ticks before cursor movement occurs, the default is 4.
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.It Va debug.cyapa_scroll_wait_ticks
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Ticks to wait before starting to scroll, the default is 0.
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.It Va debug.cyapa_scroll_stick_ticks
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Ticks while preventing cursor movement on single finger after scroll,
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the default is 15.
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.It Va debug.cyapa_thumbarea_percent
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Size of bottom thumb area in percent, the default is 15.
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.It Va debug.cyapa_debug
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Setting this to a non-zero value enables debug output to console and syslog,
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the default is 0.
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.It Va debug.cyapa_reset
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Setting this to a non-zero value reinitializes the device.
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The sysctl resets to zero immediately.
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.El
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.Sh FILES
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.Nm
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creates
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.Pa /dev/cyapa0 ,
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which presents the mouse as an
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.Ar IntelliMouse PS/2
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device.
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It supports
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.Xr moused 8
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levels 0 through 2, level 1 is used by default.
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.Sh EXAMPLES
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To use
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.Nm
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with
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.Xr moused 8 ,
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add the following lines to the
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.Xr rc.conf 5
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file:
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.Pp
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.Dl moused_enable="YES"
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.Dl moused_port="/dev/cyapa0"
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.Pp
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If vertical scrolling is not desired, add
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.Pp
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.Dl moused_flags="-l0"
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.Pp
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to
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.Xr rc.conf 5 .
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.Pp
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Enable tap to click for the left and the right mouse button and
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disable the thumb area by adding these lines to the
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.Xr sysctl.conf 5
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file:
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.Pp
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.Dl debug.cyapa_thumbarea_percent=0
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.Dl debug.cyapa_enable_tapclick=2
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.Sh SEE ALSO
|
2018-12-18 21:43:33 +00:00
|
|
|
.Xr chromebook_platform 4 ,
|
2015-07-25 18:14:35 +00:00
|
|
|
.Xr ig4 4 ,
|
add iic interface to ig4 driver, move isl and cyapa to iicbus
Summary:
The hardware does not expose a classic SMBus interface.
Instead it has a lower level interface that can express a far richer
I2C protocol than what smbus offers. However, the interface does not
provide a way to explicitly generate the I2C stop and start conditions.
It's only possible to request that the stop condition is generated
after transferring the next byte in either direction. So, at least
one data byte must always be transferred.
Thus, some I2C sequences are impossible to generate, e.g., an equivalent
of smbus quick command (<start>-<slave addr>-<r/w bit>-<stop>).
At the same time isl(4) and cyapa(4) are moved to iicbus and now they use
iicbus_transfer for communication. Previously they used smbus_trans()
interface that is not defined by the SMBus protocol and was implemented
only by ig4(4). In fact, that interface was impossible to implement
for the typical SMBus controllers like intpm(4) or ichsmb(4) where
a type of the SMBus command must be programmed.
The plan is to remove smbus_trans() and all its uses.
As an aside, the smbus_trans() method deviates from the standard,
but perhaps backwards, FreeBSD convention of using 8-bit slave
addresses (shifted by 1 bit to the left). The method expects
7-bit addresses.
There is a user facing consequence of this change.
A user must now provide device hints for isl and cyapa that specify an iicbus to use
and a slave address on it.
On Chromebook hardware where isl and cyapa devices are commonly found
it is also possible to use a new chromebook_platform(4) driver that
automatically configures isl and cyapa devices. There is no need to
provide the device hints in that case,
Right now smbus(4) driver tries to discover all slaves on the bus.
That is very dangerous. Fortunately, the probing code uses smbus_trans()
to do its job, so it is really enabled for ig4 only.
The plan is to remove that auto-probing code and smbus_trans().
Tested by: grembo, Matthias Apitz <guru@unixarea.de> (w/o
chromebook_platform)
Discussed with: grembo, imp
Reviewed by: wblock (docs)
MFC after: 1 month
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D8172
2016-10-30 12:15:33 +00:00
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.Xr iicbus 4 ,
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2016-03-28 16:48:28 +00:00
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.Xr sysmouse 4 ,
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.Xr moused 8
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2015-07-25 18:14:35 +00:00
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.Sh AUTHORS
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.An -nosplit
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The original
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.Nm
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2020-05-01 10:02:38 +00:00
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driver was written for
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.Dx
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by
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2015-07-25 18:14:35 +00:00
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.An Matthew Dillon .
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.Pp
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It has been ported, modified, and enhanced for
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.Fx
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by
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.An Michael Gmelin Aq Mt freebsd@grem.de .
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.Pp
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This manual page was written by
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.An Michael Gmelin Aq Mt freebsd@grem.de .
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.Sh BUGS
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The
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.Nm
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add iic interface to ig4 driver, move isl and cyapa to iicbus
Summary:
The hardware does not expose a classic SMBus interface.
Instead it has a lower level interface that can express a far richer
I2C protocol than what smbus offers. However, the interface does not
provide a way to explicitly generate the I2C stop and start conditions.
It's only possible to request that the stop condition is generated
after transferring the next byte in either direction. So, at least
one data byte must always be transferred.
Thus, some I2C sequences are impossible to generate, e.g., an equivalent
of smbus quick command (<start>-<slave addr>-<r/w bit>-<stop>).
At the same time isl(4) and cyapa(4) are moved to iicbus and now they use
iicbus_transfer for communication. Previously they used smbus_trans()
interface that is not defined by the SMBus protocol and was implemented
only by ig4(4). In fact, that interface was impossible to implement
for the typical SMBus controllers like intpm(4) or ichsmb(4) where
a type of the SMBus command must be programmed.
The plan is to remove smbus_trans() and all its uses.
As an aside, the smbus_trans() method deviates from the standard,
but perhaps backwards, FreeBSD convention of using 8-bit slave
addresses (shifted by 1 bit to the left). The method expects
7-bit addresses.
There is a user facing consequence of this change.
A user must now provide device hints for isl and cyapa that specify an iicbus to use
and a slave address on it.
On Chromebook hardware where isl and cyapa devices are commonly found
it is also possible to use a new chromebook_platform(4) driver that
automatically configures isl and cyapa devices. There is no need to
provide the device hints in that case,
Right now smbus(4) driver tries to discover all slaves on the bus.
That is very dangerous. Fortunately, the probing code uses smbus_trans()
to do its job, so it is really enabled for ig4 only.
The plan is to remove that auto-probing code and smbus_trans().
Tested by: grembo, Matthias Apitz <guru@unixarea.de> (w/o
chromebook_platform)
Discussed with: grembo, imp
Reviewed by: wblock (docs)
MFC after: 1 month
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D8172
2016-10-30 12:15:33 +00:00
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driver detects the device from the I2C address.
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2015-07-25 18:14:35 +00:00
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This might have unforeseen consequences if the initialization sequence
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is sent to an unknown device at that address.
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