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diff --git a/Documentation/parport.txt b/Documentation/parport.txt deleted file mode 100644 index c208e4366c03..000000000000 --- a/Documentation/parport.txt +++ /dev/null @@ -1,267 +0,0 @@ -The `parport' code provides parallel-port support under Linux. This -includes the ability to share one port between multiple device -drivers. - -You can pass parameters to the parport code to override its automatic -detection of your hardware. This is particularly useful if you want -to use IRQs, since in general these can't be autoprobed successfully. -By default IRQs are not used even if they _can_ be probed. This is -because there are a lot of people using the same IRQ for their -parallel port and a sound card or network card. - -The parport code is split into two parts: generic (which deals with -port-sharing) and architecture-dependent (which deals with actually -using the port). - - -Parport as modules -================== - -If you load the parport code as a module, say - - # insmod parport - -to load the generic parport code. You then must load the -architecture-dependent code with (for example): - - # insmod parport_pc io=0x3bc,0x378,0x278 irq=none,7,auto - -to tell the parport code that you want three PC-style ports, one at -0x3bc with no IRQ, one at 0x378 using IRQ 7, and one at 0x278 with an -auto-detected IRQ. Currently, PC-style (parport_pc), Sun `bpp', -Amiga, Atari, and MFC3 hardware is supported. - -PCI parallel I/O card support comes from parport_pc. Base I/O -addresses should not be specified for supported PCI cards since they -are automatically detected. - - -modprobe --------- - -If you use modprobe , you will find it useful to add lines as below to a -configuration file in /etc/modprobe.d/ directory:. - - alias parport_lowlevel parport_pc - options parport_pc io=0x378,0x278 irq=7,auto - -modprobe will load parport_pc (with the options "io=0x378,0x278 irq=7,auto") -whenever a parallel port device driver (such as lp) is loaded. - -Note that these are example lines only! You shouldn't in general need -to specify any options to parport_pc in order to be able to use a -parallel port. - - -Parport probe [optional] -------------- - -In 2.2 kernels there was a module called parport_probe, which was used -for collecting IEEE 1284 device ID information. This has now been -enhanced and now lives with the IEEE 1284 support. When a parallel -port is detected, the devices that are connected to it are analysed, -and information is logged like this: - - parport0: Printer, BJC-210 (Canon) - -The probe information is available from files in /proc/sys/dev/parport/. - - -Parport linked into the kernel statically -========================================= - -If you compile the parport code into the kernel, then you can use -kernel boot parameters to get the same effect. Add something like the -following to your LILO command line: - - parport=0x3bc parport=0x378,7 parport=0x278,auto,nofifo - -You can have many `parport=...' statements, one for each port you want -to add. Adding `parport=0' to the kernel command-line will disable -parport support entirely. Adding `parport=auto' to the kernel -command-line will make parport use any IRQ lines or DMA channels that -it auto-detects. - - -Files in /proc -============== - -If you have configured the /proc filesystem into your kernel, you will -see a new directory entry: /proc/sys/dev/parport. In there will be a -directory entry for each parallel port for which parport is -configured. In each of those directories are a collection of files -describing that parallel port. - -The /proc/sys/dev/parport directory tree looks like: - -parport -|-- default -| |-- spintime -| `-- timeslice -|-- parport0 -| |-- autoprobe -| |-- autoprobe0 -| |-- autoprobe1 -| |-- autoprobe2 -| |-- autoprobe3 -| |-- devices -| | |-- active -| | `-- lp -| | `-- timeslice -| |-- base-addr -| |-- irq -| |-- dma -| |-- modes -| `-- spintime -`-- parport1 - |-- autoprobe - |-- autoprobe0 - |-- autoprobe1 - |-- autoprobe2 - |-- autoprobe3 - |-- devices - | |-- active - | `-- ppa - | `-- timeslice - |-- base-addr - |-- irq - |-- dma - |-- modes - `-- spintime - - -File: Contents: - -devices/active A list of the device drivers using that port. A "+" - will appear by the name of the device currently using - the port (it might not appear against any). The - string "none" means that there are no device drivers - using that port. - -base-addr Parallel port's base address, or addresses if the port - has more than one in which case they are separated - with tabs. These values might not have any sensible - meaning for some ports. - -irq Parallel port's IRQ, or -1 if none is being used. - -dma Parallel port's DMA channel, or -1 if none is being - used. - -modes Parallel port's hardware modes, comma-separated, - meaning: - - PCSPP PC-style SPP registers are available. - TRISTATE Port is bidirectional. - COMPAT Hardware acceleration for printers is - available and will be used. - EPP Hardware acceleration for EPP protocol - is available and will be used. - ECP Hardware acceleration for ECP protocol - is available and will be used. - DMA DMA is available and will be used. - - Note that the current implementation will only take - advantage of COMPAT and ECP modes if it has an IRQ - line to use. - -autoprobe Any IEEE-1284 device ID information that has been - acquired from the (non-IEEE 1284.3) device. - -autoprobe[0-3] IEEE 1284 device ID information retrieved from - daisy-chain devices that conform to IEEE 1284.3. - -spintime The number of microseconds to busy-loop while waiting - for the peripheral to respond. You might find that - adjusting this improves performance, depending on your - peripherals. This is a port-wide setting, i.e. it - applies to all devices on a particular port. - -timeslice The number of milliseconds that a device driver is - allowed to keep a port claimed for. This is advisory, - and driver can ignore it if it must. - -default/* The defaults for spintime and timeslice. When a new - port is registered, it picks up the default spintime. - When a new device is registered, it picks up the - default timeslice. - -Device drivers -============== - -Once the parport code is initialised, you can attach device drivers to -specific ports. Normally this happens automatically; if the lp driver -is loaded it will create one lp device for each port found. You can -override this, though, by using parameters either when you load the lp -driver: - - # insmod lp parport=0,2 - -or on the LILO command line: - - lp=parport0 lp=parport2 - -Both the above examples would inform lp that you want /dev/lp0 to be -the first parallel port, and /dev/lp1 to be the _third_ parallel port, -with no lp device associated with the second port (parport1). Note -that this is different to the way older kernels worked; there used to -be a static association between the I/O port address and the device -name, so /dev/lp0 was always the port at 0x3bc. This is no longer the -case - if you only have one port, it will default to being /dev/lp0, -regardless of base address. - -Also: - - * If you selected the IEEE 1284 support at compile time, you can say - `lp=auto' on the kernel command line, and lp will create devices - only for those ports that seem to have printers attached. - - * If you give PLIP the `timid' parameter, either with `plip=timid' on - the command line, or with `insmod plip timid=1' when using modules, - it will avoid any ports that seem to be in use by other devices. - - * IRQ autoprobing works only for a few port types at the moment. - -Reporting printer problems with parport -======================================= - -If you are having problems printing, please go through these steps to -try to narrow down where the problem area is. - -When reporting problems with parport, really you need to give all of -the messages that parport_pc spits out when it initialises. There are -several code paths: - -o polling -o interrupt-driven, protocol in software -o interrupt-driven, protocol in hardware using PIO -o interrupt-driven, protocol in hardware using DMA - -The kernel messages that parport_pc logs give an indication of which -code path is being used. (They could be a lot better actually..) - -For normal printer protocol, having IEEE 1284 modes enabled or not -should not make a difference. - -To turn off the 'protocol in hardware' code paths, disable -CONFIG_PARPORT_PC_FIFO. Note that when they are enabled they are not -necessarily _used_; it depends on whether the hardware is available, -enabled by the BIOS, and detected by the driver. - -So, to start with, disable CONFIG_PARPORT_PC_FIFO, and load parport_pc -with 'irq=none'. See if printing works then. It really should, -because this is the simplest code path. - -If that works fine, try with 'io=0x378 irq=7' (adjust for your -hardware), to make it use interrupt-driven in-software protocol. - -If _that_ works fine, then one of the hardware modes isn't working -right. Enable CONFIG_PARPORT_PC_FIFO (no, it isn't a module option, -and yes, it should be), set the port to ECP mode in the BIOS and note -the DMA channel, and try with: - - io=0x378 irq=7 dma=none (for PIO) - io=0x378 irq=7 dma=3 (for DMA) --- -philb@gnu.org -tim@cyberelk.net |