<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN"
"http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" []>
<book id="Z85230Guide">
<bookinfo>
<title>Z8530 Programming Guide</title>
<authorgroup>
<author>
<firstname>Alan</firstname>
<surname>Cox</surname>
<affiliation>
<address>
<email>alan@lxorguk.ukuu.org.uk</email>
</address>
</affiliation>
</author>
</authorgroup>
<copyright>
<year>2000</year>
<holder>Alan Cox</holder>
</copyright>
<legalnotice>
<para>
This documentation is free software; you can redistribute
it and/or modify it under the terms of the GNU General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later
version.
</para>
<para>
This program is distributed in the hope that it will be
useful, but WITHOUT ANY WARRANTY; without even the implied
warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU General Public License for more details.
</para>
<para>
You should have received a copy of the GNU General Public
License along with this program; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston,
MA 02111-1307 USA
</para>
<para>
For more details see the file COPYING in the source
distribution of Linux.
</para>
</legalnotice>
</bookinfo>
<toc></toc>
<chapter id="intro">
<title>Introduction</title>
<para>
The Z85x30 family synchronous/asynchronous controller chips are
used on a large number of cheap network interface cards. The
kernel provides a core interface layer that is designed to make
it easy to provide WAN services using this chip.
</para>
<para>
The current driver only support synchronous operation. Merging the
asynchronous driver support into this code to allow any Z85x30
device to be used as both a tty interface and as a synchronous
controller is a project for Linux post the 2.4 release
</para>
</chapter>
<chapter id="Driver_Modes">
<title>Driver Modes</title>
<para>
The Z85230 driver layer can drive Z8530, Z85C30 and Z85230 devices
in three different modes. Each mode can be applied to an individual
channel on the chip (each chip has two channels).
</para>
<para>
The PIO synchronous mode supports the most common Z8530 wiring. Here
the chip is interface to the I/O and interrupt facilities of the
host machine but not to the DMA subsystem. When running PIO the
Z8530 has extremely tight timing requirements. Doing high speeds,
even with a Z85230 will be tricky. Typically you should expect to
achieve at best 9600 baud with a Z8C530 and 64Kbits with a Z85230.
</para>
<para>
The DMA mode supports the chip when it is configured to use dual DMA
channels on an ISA bus. The better cards tend to support this mode
of operation for a single channel. With DMA running the Z85230 tops
out when it starts to hit ISA DMA constraints at about 512Kbits. It
is worth noting here that many PC machines hang or crash when the
chip is driven fast enough to hold the ISA bus solid.
</para>
<para>
Transmit DMA mode uses a single DMA channel. The DMA channel is used
for transmission as the transmit FIFO is smaller than the receive
FIFO. it gives better performance than pure PIO mode but is nowhere
near as ideal as pure DMA mode.
</para>
</chapter>
<chapter id="Using_the_Z85230_driver">
<title>Using the Z85230 driver</title>
<para>
The Z85230 driver provides the back end interface to your board. To
configure a Z8530 interface you need to detect the board and to
identify its ports and interrupt resources. It is also your problem
to verify the resources are available.
</para>
<para>
Having identified the chip you need to fill in a struct z8530_dev,
which describes each chip. This object must exist until you finally
shutdown the board. Firstly zero the active field. This ensures
nothing goes off without you intending it. The irq field should
be set to the interrupt number of the chip. (Each chip has a single
interrupt source rather than each channel). You are responsible
for allocating the interrupt line. The interrupt handler should be
set to <function>z8530_interrupt</function>. The device id should
be set to the z8530_dev structure pointer. Whether the interrupt can
be shared or not is board dependent, and up to you to initialise.
</para>
<para>
The structure holds two channel structures.
Initialise chanA.ctrlio and chanA.dataio with the address of the
control and data ports. You can or this with Z8530_PORT_SLEEP to
indicate your interface needs the 5uS delay for chip settling done
in software. The PORT_SLEEP option is architecture specific. Other
flags may become available on future platforms, eg for MMIO.
Initialise the chanA.irqs to &z8530_nop to start the chip up
as disabled and discarding interrupt events. This ensures that
stray interrupts will be mopped up and not hang the bus. Set
chanA.dev to point to the device structure itself. The
private and name field you may use as you wish. The private field
is unused by the Z85230 layer. The name is used for error reporting
and it may thus make sense to make it match the network name.
</para>
<para>
Repeat the same operation with the B channel if your chip has
both channels wired to something useful. This isn't always the
case. If it is not wired then the I/O values do not matter, but
you must initialise chanB.dev.
</para>
<para>
If your board has DMA facilities then initialise the txdma and
rxdma fields for the relevant channels. You must also allocate the
ISA DMA channels and do any necessary board level initialisation
to configure them. The low level driver will do the Z8530 and
DMA controller programming but not board specific magic.
</para>
<para>
Having initialised the device you can then call
<function>z8530_init</function>. This will probe the chip and
reset it into a known state. An identification sequence is then
run to identify the chip type. If the checks fail to pass the
function returns a non zero error code. Typically this indicates
that the port given is not valid. After this call the
type field of the z8530_dev structure is initialised to either
Z8530, Z85C30 or Z85230 according to the chip found.
</para>
<para>
Once you have called z8530_init you can also make use of the utility
function <function>z8530_describe</function>. This provides a
consistent reporting format for the Z8530 devices, and allows all
the drivers to provide consistent reporting.
</para>
</chapter>
<chapter id="Attaching_Network_Interfaces">
<title>Attaching Network Interfaces</title>
<para>
If you wish to use the network interface facilities of the driver,
then you need to attach a network device to each channel that is
present and in use. In addition to use the generic HDLC
you need to follow some additional plumbing rules. They may seem
complex but a look at the example hostess_sv11 driver should
reassure you.
</para>
<para>
The network device used for each channel should be pointed to by
the netdevice field of each channel. The hdlc-> priv field of the
network device points to your private data - you will need to be
able to find your private data from this.
</para>
<para>
The way most drivers approach this particular problem is to
create a structure holding the Z8530 device definition and
put that into the private field of the network device. The
network device fields of the channels then point back to the
network devices.
</para>
<para>
If you wish to use the generic HDLC then you need to register
the HDLC device.
</para>
<para>
Before you register your network device you will also need to
provide suitable handlers for most of the network device callbacks.
See the network device documentation for more details on this.
</para>
</chapter>
<chapter id="Configuring_And_Activating_The_Port">
<title>Configuring And Activating The Port</title>
<para>
The Z85230 driver provides helper functions and tables to load the
port registers on the Z8530 chips. When programming the register
settings for a channel be aware that the documentation recommends
initialisation orders. Strange things happen when these are not
followed.
</para>
<para>
<function>z8530_channel_load</function> takes an array of
pairs of initialisation values in an array of u8 type. The first
value is the Z8530 register number. Add 16 to indicate the alternate
register bank on the later chips. The array is terminated by a 255.
</para>
<para>
The driver provides a pair of public tables. The
z8530_hdlc_kilostream table is for the UK 'Kilostream' service and
also happens to cover most other end host configurations. The
z8530_hdlc_kilostream_85230 table is the same configuration using
the enhancements of the 85230 chip. The configuration loaded is
standard NRZ encoded synchronous data with HDLC bitstuffing. All
of the timing is taken from the other end of the link.
</para>
<para>
When writing your own tables be aware that the driver internally
tracks register values. It may need to reload values. You should
therefore be sure to set registers 1-7, 9-11, 14 and 15 in all
configurations. Where the register settings depend on DMA selection
the driver will update the bits itself when you open or close.
Loading a new table with the interface open is not recommended.
</para>
<para>
There are three standard configurations supported by the core
code. In PIO mode the interface is programmed up to use
interrupt driven PIO. This places high demands on the host processor
to avoid latency. The driver is written to take account of latency
issues but it cannot avoid latencies caused by other drivers,
notably IDE in PIO mode. Because the drivers allocate buffers you
must also prevent MTU changes while the port is open.
</para>
<para>
Once the port is open it will call the rx_function of each channel
whenever a completed packet arrived. This is invoked from
interrupt context and passes you the channel and a network
buffer (struct sk_buff) holding the data. The data includes
the CRC bytes so most users will want to trim the last two
bytes before processing the data. This function is very timing
critical. When you wish to simply discard data the support
code provides the function <function>z8530_null_rx</function>
to discard the data.
</para>
<para>
To active PIO mode sending and receiving the <function>
z8530_sync_open</function> is called. This expects to be passed
the network device and the channel. Typically this is called from
your network device open callback. On a failure a non zero error
status is returned. The <function>z8530_sync_close</function>
function shuts down a PIO channel. This must be done before the
channel is opened again and before the driver shuts down
and unloads.
</para>
<para>
The ideal mode of operation is dual channel DMA mode. Here the
kernel driver will configure the board for DMA in both directions.
The driver also handles ISA DMA issues such as controller
programming and the memory range limit for you. This mode is
activated by calling the <function>z8530_sync_dma_open</function>
function. On failure a non zero error value is returned.
Once this mode is activated it can be shut down by calling the
<function>z8530_sync_dma_close</function>. You must call the close
function matching the open mode you used.
</para>
<para>
The final supported mode uses a single DMA channel to drive the
transmit side. As the Z85C30 has a larger FIFO on the receive
channel this tends to increase the maximum speed a little.
This is activated by calling the <function>z8530_sync_txdma_open
</function>. This returns a non zero error code on failure. The
<function>z8530_sync_txdma_close</function> function closes down
the Z8530 interface from this mode.
</para>
</chapter>
<chapter id="Network_Layer_Functions">
<title>Network Layer Functions</title>
<para>
The Z8530 layer provides functions to queue packets for
transmission. The driver internally buffers the frame currently
being transmitted and one further frame (in order to keep back
to back transmission running). Any further buffering is up to
the caller.
</para>
<para>
The function <function>z8530_queue_xmit</function> takes a network
buffer in sk_buff format and queues it for transmission. The
caller must provide the entire packet with the exception of the
bitstuffing and CRC. This is normally done by the caller via
the generic HDLC interface layer. It returns 0 if the buffer has been
queued and non zero values for queue full. If the function accepts
the buffer it becomes property of the Z8530 layer and the caller
should not free it.
</para>
<para>
The function <function>z8530_get_stats</function> returns a pointer
to an internally maintained per interface statistics block. This
provides most of the interface code needed to implement the network
layer get_stats callback.
</para>
</chapter>
<chapter id="Porting_The_Z8530_Driver">
<title>Porting The Z8530 Driver</title>
<para>
The Z8530 driver is written to be portable. In DMA mode it makes
assumptions about the use of ISA DMA. These are probably warranted
in most cases as the Z85230 in particular was designed to glue to PC
type machines. The PIO mode makes no real assumptions.
</para>
<para>
Should you need to retarget the Z8530 driver to another architecture
the only code that should need changing are the port I/O functions.
At the moment these assume PC I/O port accesses. This may not be
appropriate for all platforms. Replacing
<function>z8530_read_port</function> and <function>z8530_write_port
</function> is intended to be all that is required to port this
driver layer.
</para>
</chapter>
<chapter id="bugs">
<title>Known Bugs And Assumptions</title>
<para>
<variablelist>
<varlistentry><term>Interrupt Locking</term>
<listitem>
<para>
The locking in the driver is done via the global cli/sti lock. This
makes for relatively poor SMP performance. Switching this to use a
per device spin lock would probably materially improve performance.
</para>
</listitem></varlistentry>
<varlistentry><term>Occasional Failures</term>
<listitem>
<para>
We have reports of occasional failures when run for very long
periods of time and the driver starts to receive junk frames. At
the moment the cause of this is not clear.
</para>
</listitem></varlistentry>
</variablelist>
</para>
</chapter>
<chapter id="pubfunctions">
<title>Public Functions Provided</title>
<!-- drivers/net/wan/z85230.c -->
<refentry id="API-z8530-interrupt">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_interrupt</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_interrupt</refname>
<refpurpose>
Handle an interrupt from a Z8530
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>irqreturn_t <function>z8530_interrupt </function></funcdef>
<paramdef>int <parameter>irq</parameter></paramdef>
<paramdef>void * <parameter>dev_id</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>irq</parameter></term>
<listitem>
<para>
Interrupt number
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>dev_id</parameter></term>
<listitem>
<para>
The Z8530 device that is interrupting.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
A Z85[2]30 device has stuck its hand in the air for attention.
We scan both the channels on the chip for events and then call
the channel specific call backs for each channel that has events.
We have to use callback functions because the two channels can be
in different modes.
</para><para>
Locking is done for the handlers. Note that locking is done
at the chip level (the 5uS delay issue is per chip not per
channel). c->lock for both channels points to dev->lock
</para>
</refsect1>
</refentry>
<refentry id="API-z8530-sync-open">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_sync_open</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_sync_open</refname>
<refpurpose>
Open a Z8530 channel for PIO
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>int <function>z8530_sync_open </function></funcdef>
<paramdef>struct net_device * <parameter>dev</parameter></paramdef>
<paramdef>struct z8530_channel * <parameter>c</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>dev</parameter></term>
<listitem>
<para>
The network interface we are using
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>c</parameter></term>
<listitem>
<para>
The Z8530 channel to open in synchronous PIO mode
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
Switch a Z8530 into synchronous mode without DMA assist. We
raise the RTS/DTR and commence network operation.
</para>
</refsect1>
</refentry>
<refentry id="API-z8530-sync-close">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_sync_close</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_sync_close</refname>
<refpurpose>
Close a PIO Z8530 channel
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>int <function>z8530_sync_close </function></funcdef>
<paramdef>struct net_device * <parameter>dev</parameter></paramdef>
<paramdef>struct z8530_channel * <parameter>c</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>dev</parameter></term>
<listitem>
<para>
Network device to close
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>c</parameter></term>
<listitem>
<para>
Z8530 channel to disassociate and move to idle
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
Close down a Z8530 interface and switch its interrupt handlers
to discard future events.
</para>
</refsect1>
</refentry>
<refentry id="API-z8530-sync-dma-open">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_sync_dma_open</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_sync_dma_open</refname>
<refpurpose>
Open a Z8530 for DMA I/O
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>int <function>z8530_sync_dma_open </function></funcdef>
<paramdef>struct net_device * <parameter>dev</parameter></paramdef>
<paramdef>struct z8530_channel * <parameter>c</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>dev</parameter></term>
<listitem>
<para>
The network device to attach
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>c</parameter></term>
<listitem>
<para>
The Z8530 channel to configure in sync DMA mode.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
Set up a Z85x30 device for synchronous DMA in both directions. Two
ISA DMA channels must be available for this to work. We assume ISA
DMA driven I/O and PC limits on access.
</para>
</refsect1>
</refentry>
<refentry id="API-z8530-sync-dma-close">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_sync_dma_close</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_sync_dma_close</refname>
<refpurpose>
Close down DMA I/O
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>int <function>z8530_sync_dma_close </function></funcdef>
<paramdef>struct net_device * <parameter>dev</parameter></paramdef>
<paramdef>struct z8530_channel * <parameter>c</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>dev</parameter></term>
<listitem>
<para>
Network device to detach
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>c</parameter></term>
<listitem>
<para>
Z8530 channel to move into discard mode
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
Shut down a DMA mode synchronous interface. Halt the DMA, and
free the buffers.
</para>
</refsect1>
</refentry>
<refentry id="API-z8530-sync-txdma-open">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_sync_txdma_open</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_sync_txdma_open</refname>
<refpurpose>
Open a Z8530 for TX driven DMA
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>int <function>z8530_sync_txdma_open </function></funcdef>
<paramdef>struct net_device * <parameter>dev</parameter></paramdef>
<paramdef>struct z8530_channel * <parameter>c</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>dev</parameter></term>
<listitem>
<para>
The network device to attach
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>c</parameter></term>
<listitem>
<para>
The Z8530 channel to configure in sync DMA mode.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
Set up a Z85x30 device for synchronous DMA tranmission. One
ISA DMA channel must be available for this to work. The receive
side is run in PIO mode, but then it has the bigger FIFO.
</para>
</refsect1>
</refentry>
<refentry id="API-z8530-sync-txdma-close">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_sync_txdma_close</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_sync_txdma_close</refname>
<refpurpose>
Close down a TX driven DMA channel
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>int <function>z8530_sync_txdma_close </function></funcdef>
<paramdef>struct net_device * <parameter>dev</parameter></paramdef>
<paramdef>struct z8530_channel * <parameter>c</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>dev</parameter></term>
<listitem>
<para>
Network device to detach
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>c</parameter></term>
<listitem>
<para>
Z8530 channel to move into discard mode
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
Shut down a DMA/PIO split mode synchronous interface. Halt the DMA,
and free the buffers.
</para>
</refsect1>
</refentry>
<refentry id="API-z8530-describe">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_describe</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_describe</refname>
<refpurpose>
Uniformly describe a Z8530 port
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>void <function>z8530_describe </function></funcdef>
<paramdef>struct z8530_dev * <parameter>dev</parameter></paramdef>
<paramdef>char * <parameter>mapping</parameter></paramdef>
<paramdef>unsigned long <parameter>io</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>dev</parameter></term>
<listitem>
<para>
Z8530 device to describe
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>mapping</parameter></term>
<listitem>
<para>
string holding mapping type (eg <quote>I/O</quote> or <quote>Mem</quote>)
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>io</parameter></term>
<listitem>
<para>
the port value in question
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
Describe a Z8530 in a standard format. We must pass the I/O as
the port offset isnt predictable. The main reason for this function
is to try and get a common format of report.
</para>
</refsect1>
</refentry>
<refentry id="API-z8530-init">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_init</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_init</refname>
<refpurpose>
Initialise a Z8530 device
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>int <function>z8530_init </function></funcdef>
<paramdef>struct z8530_dev * <parameter>dev</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>dev</parameter></term>
<listitem>
<para>
Z8530 device to initialise.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
Configure up a Z8530/Z85C30 or Z85230 chip. We check the device
is present, identify the type and then program it to hopefully
keep quite and behave. This matters a lot, a Z8530 in the wrong
state will sometimes get into stupid modes generating 10Khz
interrupt streams and the like.
</para><para>
We set the interrupt handler up to discard any events, in case
we get them during reset or setp.
</para><para>
Return 0 for success, or a negative value indicating the problem
in errno form.
</para>
</refsect1>
</refentry>
<refentry id="API-z8530-shutdown">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_shutdown</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_shutdown</refname>
<refpurpose>
Shutdown a Z8530 device
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>int <function>z8530_shutdown </function></funcdef>
<paramdef>struct z8530_dev * <parameter>dev</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>dev</parameter></term>
<listitem>
<para>
The Z8530 chip to shutdown
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
We set the interrupt handlers to silence any interrupts. We then
reset the chip and wait 100uS to be sure the reset completed. Just
in case the caller then tries to do stuff.
</para><para>
This is called without the lock held
</para>
</refsect1>
</refentry>
<refentry id="API-z8530-channel-load">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_channel_load</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_channel_load</refname>
<refpurpose>
Load channel data
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>int <function>z8530_channel_load </function></funcdef>
<paramdef>struct z8530_channel * <parameter>c</parameter></paramdef>
<paramdef>u8 * <parameter>rtable</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>c</parameter></term>
<listitem>
<para>
Z8530 channel to configure
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>rtable</parameter></term>
<listitem>
<para>
table of register, value pairs
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>FIXME</title>
<para>
ioctl to allow user uploaded tables
</para><para>
Load a Z8530 channel up from the system data. We use +16 to
indicate the <quote>prime</quote> registers. The value 255 terminates the
table.
</para>
</refsect1>
</refentry>
<refentry id="API-z8530-null-rx">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_null_rx</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_null_rx</refname>
<refpurpose>
Discard a packet
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>void <function>z8530_null_rx </function></funcdef>
<paramdef>struct z8530_channel * <parameter>c</parameter></paramdef>
<paramdef>struct sk_buff * <parameter>skb</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>c</parameter></term>
<listitem>
<para>
The channel the packet arrived on
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>skb</parameter></term>
<listitem>
<para>
The buffer
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
We point the receive handler at this function when idle. Instead
of processing the frames we get to throw them away.
</para>
</refsect1>
</refentry>
<refentry id="API-z8530-queue-xmit">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_queue_xmit</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_queue_xmit</refname>
<refpurpose>
Queue a packet
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>netdev_tx_t <function>z8530_queue_xmit </function></funcdef>
<paramdef>struct z8530_channel * <parameter>c</parameter></paramdef>
<paramdef>struct sk_buff * <parameter>skb</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>c</parameter></term>
<listitem>
<para>
The channel to use
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>skb</parameter></term>
<listitem>
<para>
The packet to kick down the channel
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
Queue a packet for transmission. Because we have rather
hard to hit interrupt latencies for the Z85230 per packet
even in DMA mode we do the flip to DMA buffer if needed here
not in the IRQ.
</para><para>
Called from the network code. The lock is not held at this
point.
</para>
</refsect1>
</refentry>
</chapter>
<chapter id="intfunctions">
<title>Internal Functions</title>
<!-- drivers/net/wan/z85230.c -->
<refentry id="API-z8530-read-port">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_read_port</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_read_port</refname>
<refpurpose>
Architecture specific interface function
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>int <function>z8530_read_port </function></funcdef>
<paramdef>unsigned long <parameter>p</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>p</parameter></term>
<listitem>
<para>
port to read
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
Provided port access methods. The Comtrol SV11 requires no delays
between accesses and uses PC I/O. Some drivers may need a 5uS delay
</para><para>
In the longer term this should become an architecture specific
section so that this can become a generic driver interface for all
platforms. For now we only handle PC I/O ports with or without the
dread 5uS sanity delay.
</para><para>
The caller must hold sufficient locks to avoid violating the horrible
5uS delay rule.
</para>
</refsect1>
</refentry>
<refentry id="API-z8530-write-port">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_write_port</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_write_port</refname>
<refpurpose>
Architecture specific interface function
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>void <function>z8530_write_port </function></funcdef>
<paramdef>unsigned long <parameter>p</parameter></paramdef>
<paramdef>u8 <parameter>d</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>p</parameter></term>
<listitem>
<para>
port to write
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>d</parameter></term>
<listitem>
<para>
value to write
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
Write a value to a port with delays if need be. Note that the
caller must hold locks to avoid read/writes from other contexts
violating the 5uS rule
</para><para>
In the longer term this should become an architecture specific
section so that this can become a generic driver interface for all
platforms. For now we only handle PC I/O ports with or without the
dread 5uS sanity delay.
</para>
</refsect1>
</refentry>
<refentry id="API-read-zsreg">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>read_zsreg</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>read_zsreg</refname>
<refpurpose>
Read a register from a Z85230
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>u8 <function>read_zsreg </function></funcdef>
<paramdef>struct z8530_channel * <parameter>c</parameter></paramdef>
<paramdef>u8 <parameter>reg</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>c</parameter></term>
<listitem>
<para>
Z8530 channel to read from (2 per chip)
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>reg</parameter></term>
<listitem>
<para>
Register to read
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>FIXME</title>
<para>
Use a spinlock.
</para><para>
Most of the Z8530 registers are indexed off the control registers.
A read is done by writing to the control register and reading the
register back. The caller must hold the lock
</para>
</refsect1>
</refentry>
<refentry id="API-read-zsdata">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>read_zsdata</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>read_zsdata</refname>
<refpurpose>
Read the data port of a Z8530 channel
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>u8 <function>read_zsdata </function></funcdef>
<paramdef>struct z8530_channel * <parameter>c</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>c</parameter></term>
<listitem>
<para>
The Z8530 channel to read the data port from
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
The data port provides fast access to some things. We still
have all the 5uS delays to worry about.
</para>
</refsect1>
</refentry>
<refentry id="API-write-zsreg">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>write_zsreg</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>write_zsreg</refname>
<refpurpose>
Write to a Z8530 channel register
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>void <function>write_zsreg </function></funcdef>
<paramdef>struct z8530_channel * <parameter>c</parameter></paramdef>
<paramdef>u8 <parameter>reg</parameter></paramdef>
<paramdef>u8 <parameter>val</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>c</parameter></term>
<listitem>
<para>
The Z8530 channel
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>reg</parameter></term>
<listitem>
<para>
Register number
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>val</parameter></term>
<listitem>
<para>
Value to write
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
Write a value to an indexed register. The caller must hold the lock
to honour the irritating delay rules. We know about register 0
being fast to access.
</para><para>
Assumes c->lock is held.
</para>
</refsect1>
</refentry>
<refentry id="API-write-zsctrl">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>write_zsctrl</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>write_zsctrl</refname>
<refpurpose>
Write to a Z8530 control register
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>void <function>write_zsctrl </function></funcdef>
<paramdef>struct z8530_channel * <parameter>c</parameter></paramdef>
<paramdef>u8 <parameter>val</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>c</parameter></term>
<listitem>
<para>
The Z8530 channel
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>val</parameter></term>
<listitem>
<para>
Value to write
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
Write directly to the control register on the Z8530
</para>
</refsect1>
</refentry>
<refentry id="API-write-zsdata">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>write_zsdata</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>write_zsdata</refname>
<refpurpose>
Write to a Z8530 control register
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>void <function>write_zsdata </function></funcdef>
<paramdef>struct z8530_channel * <parameter>c</parameter></paramdef>
<paramdef>u8 <parameter>val</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>c</parameter></term>
<listitem>
<para>
The Z8530 channel
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>val</parameter></term>
<listitem>
<para>
Value to write
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
Write directly to the data register on the Z8530
</para>
</refsect1>
</refentry>
<refentry id="API-z8530-flush-fifo">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_flush_fifo</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_flush_fifo</refname>
<refpurpose>
Flush on chip RX FIFO
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>void <function>z8530_flush_fifo </function></funcdef>
<paramdef>struct z8530_channel * <parameter>c</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>c</parameter></term>
<listitem>
<para>
Channel to flush
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
Flush the receive FIFO. There is no specific option for this, we
blindly read bytes and discard them. Reading when there is no data
is harmless. The 8530 has a 4 byte FIFO, the 85230 has 8 bytes.
</para><para>
All locking is handled for the caller. On return data may still be
present if it arrived during the flush.
</para>
</refsect1>
</refentry>
<refentry id="API-z8530-rtsdtr">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_rtsdtr</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_rtsdtr</refname>
<refpurpose>
Control the outgoing DTS/RTS line
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>void <function>z8530_rtsdtr </function></funcdef>
<paramdef>struct z8530_channel * <parameter>c</parameter></paramdef>
<paramdef>int <parameter>set</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>c</parameter></term>
<listitem>
<para>
The Z8530 channel to control;
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>set</parameter></term>
<listitem>
<para>
1 to set, 0 to clear
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
Sets or clears DTR/RTS on the requested line. All locking is handled
by the caller. For now we assume all boards use the actual RTS/DTR
on the chip. Apparently one or two don't. We'll scream about them
later.
</para>
</refsect1>
</refentry>
<refentry id="API-z8530-rx">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_rx</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_rx</refname>
<refpurpose>
Handle a PIO receive event
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>void <function>z8530_rx </function></funcdef>
<paramdef>struct z8530_channel * <parameter>c</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>c</parameter></term>
<listitem>
<para>
Z8530 channel to process
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
Receive handler for receiving in PIO mode. This is much like the
async one but not quite the same or as complex
</para>
</refsect1>
<refsect1>
<title>Note</title>
<para>
Its intended that this handler can easily be separated from
the main code to run realtime. That'll be needed for some machines
(eg to ever clock 64kbits on a sparc ;)).
</para><para>
The RT_LOCK macros don't do anything now. Keep the code covered
by them as short as possible in all circumstances - clocks cost
baud. The interrupt handler is assumed to be atomic w.r.t. to
other code - this is true in the RT case too.
</para><para>
We only cover the sync cases for this. If you want 2Mbit async
do it yourself but consider medical assistance first. This non DMA
synchronous mode is portable code. The DMA mode assumes PCI like
ISA DMA
</para><para>
Called with the device lock held
</para>
</refsect1>
</refentry>
<refentry id="API-z8530-tx">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_tx</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_tx</refname>
<refpurpose>
Handle a PIO transmit event
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>void <function>z8530_tx </function></funcdef>
<paramdef>struct z8530_channel * <parameter>c</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>c</parameter></term>
<listitem>
<para>
Z8530 channel to process
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
Z8530 transmit interrupt handler for the PIO mode. The basic
idea is to attempt to keep the FIFO fed. We fill as many bytes
in as possible, its quite possible that we won't keep up with the
data rate otherwise.
</para>
</refsect1>
</refentry>
<refentry id="API-z8530-status">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_status</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_status</refname>
<refpurpose>
Handle a PIO status exception
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>void <function>z8530_status </function></funcdef>
<paramdef>struct z8530_channel * <parameter>chan</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>chan</parameter></term>
<listitem>
<para>
Z8530 channel to process
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
A status event occurred in PIO synchronous mode. There are several
reasons the chip will bother us here. A transmit underrun means we
failed to feed the chip fast enough and just broke a packet. A DCD
change is a line up or down.
</para>
</refsect1>
</refentry>
<refentry id="API-z8530-dma-rx">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_dma_rx</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_dma_rx</refname>
<refpurpose>
Handle a DMA RX event
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>void <function>z8530_dma_rx </function></funcdef>
<paramdef>struct z8530_channel * <parameter>chan</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>chan</parameter></term>
<listitem>
<para>
Channel to handle
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
Non bus mastering DMA interfaces for the Z8x30 devices. This
is really pretty PC specific. The DMA mode means that most receive
events are handled by the DMA hardware. We get a kick here only if
a frame ended.
</para>
</refsect1>
</refentry>
<refentry id="API-z8530-dma-tx">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_dma_tx</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_dma_tx</refname>
<refpurpose>
Handle a DMA TX event
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>void <function>z8530_dma_tx </function></funcdef>
<paramdef>struct z8530_channel * <parameter>chan</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>chan</parameter></term>
<listitem>
<para>
The Z8530 channel to handle
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
We have received an interrupt while doing DMA transmissions. It
shouldn't happen. Scream loudly if it does.
</para>
</refsect1>
</refentry>
<refentry id="API-z8530-dma-status">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_dma_status</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_dma_status</refname>
<refpurpose>
Handle a DMA status exception
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>void <function>z8530_dma_status </function></funcdef>
<paramdef>struct z8530_channel * <parameter>chan</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>chan</parameter></term>
<listitem>
<para>
Z8530 channel to process
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
A status event occurred on the Z8530. We receive these for two reasons
when in DMA mode. Firstly if we finished a packet transfer we get one
and kick the next packet out. Secondly we may see a DCD change.
</para>
</refsect1>
</refentry>
<refentry id="API-z8530-rx-clear">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_rx_clear</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_rx_clear</refname>
<refpurpose>
Handle RX events from a stopped chip
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>void <function>z8530_rx_clear </function></funcdef>
<paramdef>struct z8530_channel * <parameter>c</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>c</parameter></term>
<listitem>
<para>
Z8530 channel to shut up
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
Receive interrupt vectors for a Z8530 that is in 'parked' mode.
For machines with PCI Z85x30 cards, or level triggered interrupts
(eg the MacII) we must clear the interrupt cause or die.
</para>
</refsect1>
</refentry>
<refentry id="API-z8530-tx-clear">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_tx_clear</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_tx_clear</refname>
<refpurpose>
Handle TX events from a stopped chip
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>void <function>z8530_tx_clear </function></funcdef>
<paramdef>struct z8530_channel * <parameter>c</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>c</parameter></term>
<listitem>
<para>
Z8530 channel to shut up
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
Transmit interrupt vectors for a Z8530 that is in 'parked' mode.
For machines with PCI Z85x30 cards, or level triggered interrupts
(eg the MacII) we must clear the interrupt cause or die.
</para>
</refsect1>
</refentry>
<refentry id="API-z8530-status-clear">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_status_clear</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_status_clear</refname>
<refpurpose>
Handle status events from a stopped chip
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>void <function>z8530_status_clear </function></funcdef>
<paramdef>struct z8530_channel * <parameter>chan</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>chan</parameter></term>
<listitem>
<para>
Z8530 channel to shut up
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
Status interrupt vectors for a Z8530 that is in 'parked' mode.
For machines with PCI Z85x30 cards, or level triggered interrupts
(eg the MacII) we must clear the interrupt cause or die.
</para>
</refsect1>
</refentry>
<refentry id="API-z8530-tx-begin">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_tx_begin</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_tx_begin</refname>
<refpurpose>
Begin packet transmission
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>void <function>z8530_tx_begin </function></funcdef>
<paramdef>struct z8530_channel * <parameter>c</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>c</parameter></term>
<listitem>
<para>
The Z8530 channel to kick
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
This is the speed sensitive side of transmission. If we are called
and no buffer is being transmitted we commence the next buffer. If
nothing is queued we idle the sync.
</para>
</refsect1>
<refsect1>
<title>Note</title>
<para>
We are handling this code path in the interrupt path, keep it
fast or bad things will happen.
</para><para>
Called with the lock held.
</para>
</refsect1>
</refentry>
<refentry id="API-z8530-tx-done">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_tx_done</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_tx_done</refname>
<refpurpose>
TX complete callback
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>void <function>z8530_tx_done </function></funcdef>
<paramdef>struct z8530_channel * <parameter>c</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>c</parameter></term>
<listitem>
<para>
The channel that completed a transmit.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
This is called when we complete a packet send. We wake the queue,
start the next packet going and then free the buffer of the existing
packet. This code is fairly timing sensitive.
</para><para>
Called with the register lock held.
</para>
</refsect1>
</refentry>
<refentry id="API-z8530-rx-done">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>z8530_rx_done</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>z8530_rx_done</refname>
<refpurpose>
Receive completion callback
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>void <function>z8530_rx_done </function></funcdef>
<paramdef>struct z8530_channel * <parameter>c</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>c</parameter></term>
<listitem>
<para>
The channel that completed a receive
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
A new packet is complete. Our goal here is to get back into receive
mode as fast as possible. On the Z85230 we could change to using
ESCC mode, but on the older chips we have no choice. We flip to the
new buffer immediately in DMA mode so that the DMA of the next
frame can occur while we are copying the previous buffer to an sk_buff
</para><para>
Called with the lock held
</para>
</refsect1>
</refentry>
<refentry id="API-spans-boundary">
<refentryinfo>
<title>LINUX</title>
<productname>Kernel Hackers Manual</productname>
<date>June 2011</date>
</refentryinfo>
<refmeta>
<refentrytitle><phrase>spans_boundary</phrase></refentrytitle>
<manvolnum>9</manvolnum>
<refmiscinfo class="version">2.6.32</refmiscinfo>
</refmeta>
<refnamediv>
<refname>spans_boundary</refname>
<refpurpose>
Check a packet can be ISA DMA'd
</refpurpose>
</refnamediv>
<refsynopsisdiv>
<title>Synopsis</title>
<funcsynopsis><funcprototype>
<funcdef>int <function>spans_boundary </function></funcdef>
<paramdef>struct sk_buff * <parameter>skb</parameter></paramdef>
</funcprototype></funcsynopsis>
</refsynopsisdiv>
<refsect1>
<title>Arguments</title>
<variablelist>
<varlistentry>
<term><parameter>skb</parameter></term>
<listitem>
<para>
The buffer to check
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1>
<title>Description</title>
<para>
Returns true if the buffer cross a DMA boundary on a PC. The poor
thing can only DMA within a 64K block not across the edges of it.
</para>
</refsect1>
</refentry>
</chapter>
</book>
