staging: comedi: comedi_8255: new module split from 8255
The Comedi "8255" module is both a standalone Comedi device driver module for simple devices with one or more 8255 "Programmable Peripheral Interface" chips at known I/O base addresses (configured at run-time), and a helper module to configure a 8255-based digital I/O subdevice for other Comedi drivers. Split the "8255 subdevice helper" functionality into a new module: "comedi_8255", leaving the standalone 8255 Comedi driver in the "8255" module. The Comedi "detach" routine of the standalone "8255" driver needs to retrieve the I/O base address passed to the "comedi_8255" module to set up each subdevice in order to release the I/O port regions it requested in its "attach" routine. The "comedi_8255" module stores it in a "subdevice private" data structure that is no longer known to the "8255" module, so add a new, exported function `subdev_8255_regbase()` to retrieve it. Signed-off-by: Ian Abbott <abbotti@mev.co.uk> Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Ian Abbott
Greg Kroah-Hartman
parent
dc54ba4d88
commit
968d17786d
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@ -1247,16 +1247,22 @@ config COMEDI_8254
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tristate
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config COMEDI_8255
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tristate "Generic 8255 support"
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tristate
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config COMEDI_8255_SA
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tristate "Standalone 8255 support"
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select COMEDI_8255
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---help---
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Enable generic 8255 support.
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Enable support for 8255 digital I/O as a standalone driver.
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You should enable compilation this driver if you plan to use a board
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that has an 8255 chip. For multifunction boards, the main driver will
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configure the 8255 subdevice automatically.
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that has an 8255 chip at a known I/O base address and there are no
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other Comedi drivers for the board.
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Note that most PCI based 8255 boards use the 8255_pci driver as a
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wrapper around this driver.
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Note that Comedi drivers for most multi-function boards incorporating
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an 8255 chip use the 'comedi_8255' module. Most PCI-based 8255
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boards use the 8255_pci driver as a wrapper around the 'comedi_8255'
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module.
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To compile this driver as a module, choose M here: the module will be
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called 8255.
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@ -53,221 +53,6 @@
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#include "8255.h"
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struct subdev_8255_private {
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unsigned long regbase;
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int (*io)(struct comedi_device *dev, int dir, int port, int data,
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unsigned long regbase);
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};
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static int subdev_8255_io(struct comedi_device *dev,
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int dir, int port, int data, unsigned long regbase)
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{
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if (dir) {
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outb(data, dev->iobase + regbase + port);
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return 0;
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}
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return inb(dev->iobase + regbase + port);
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}
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static int subdev_8255_mmio(struct comedi_device *dev,
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int dir, int port, int data, unsigned long regbase)
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{
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if (dir) {
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writeb(data, dev->mmio + regbase + port);
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return 0;
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}
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return readb(dev->mmio + regbase + port);
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}
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static int subdev_8255_insn(struct comedi_device *dev,
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struct comedi_subdevice *s,
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struct comedi_insn *insn,
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unsigned int *data)
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{
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struct subdev_8255_private *spriv = s->private;
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unsigned long regbase = spriv->regbase;
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unsigned int mask;
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unsigned int v;
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mask = comedi_dio_update_state(s, data);
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if (mask) {
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if (mask & 0xff)
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spriv->io(dev, 1, I8255_DATA_A_REG,
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s->state & 0xff, regbase);
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if (mask & 0xff00)
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spriv->io(dev, 1, I8255_DATA_B_REG,
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(s->state >> 8) & 0xff, regbase);
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if (mask & 0xff0000)
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spriv->io(dev, 1, I8255_DATA_C_REG,
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(s->state >> 16) & 0xff, regbase);
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}
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v = spriv->io(dev, 0, I8255_DATA_A_REG, 0, regbase);
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v |= (spriv->io(dev, 0, I8255_DATA_B_REG, 0, regbase) << 8);
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v |= (spriv->io(dev, 0, I8255_DATA_C_REG, 0, regbase) << 16);
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data[1] = v;
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return insn->n;
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}
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static void subdev_8255_do_config(struct comedi_device *dev,
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struct comedi_subdevice *s)
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{
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struct subdev_8255_private *spriv = s->private;
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unsigned long regbase = spriv->regbase;
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int config;
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config = I8255_CTRL_CW;
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/* 1 in io_bits indicates output, 1 in config indicates input */
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if (!(s->io_bits & 0x0000ff))
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config |= I8255_CTRL_A_IO;
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if (!(s->io_bits & 0x00ff00))
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config |= I8255_CTRL_B_IO;
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if (!(s->io_bits & 0x0f0000))
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config |= I8255_CTRL_C_LO_IO;
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if (!(s->io_bits & 0xf00000))
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config |= I8255_CTRL_C_HI_IO;
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spriv->io(dev, 1, I8255_CTRL_REG, config, regbase);
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}
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static int subdev_8255_insn_config(struct comedi_device *dev,
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struct comedi_subdevice *s,
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struct comedi_insn *insn,
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unsigned int *data)
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{
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unsigned int chan = CR_CHAN(insn->chanspec);
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unsigned int mask;
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int ret;
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if (chan < 8)
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mask = 0x0000ff;
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else if (chan < 16)
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mask = 0x00ff00;
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else if (chan < 20)
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mask = 0x0f0000;
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else
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mask = 0xf00000;
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ret = comedi_dio_insn_config(dev, s, insn, data, mask);
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if (ret)
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return ret;
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subdev_8255_do_config(dev, s);
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return insn->n;
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}
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static int __subdev_8255_init(struct comedi_device *dev,
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struct comedi_subdevice *s,
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int (*io)(struct comedi_device *dev,
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int dir, int port, int data,
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unsigned long regbase),
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unsigned long regbase,
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bool is_mmio)
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{
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struct subdev_8255_private *spriv;
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spriv = comedi_alloc_spriv(s, sizeof(*spriv));
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if (!spriv)
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return -ENOMEM;
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if (io)
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spriv->io = io;
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else if (is_mmio)
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spriv->io = subdev_8255_mmio;
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else
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spriv->io = subdev_8255_io;
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spriv->regbase = regbase;
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s->type = COMEDI_SUBD_DIO;
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s->subdev_flags = SDF_READABLE | SDF_WRITABLE;
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s->n_chan = 24;
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s->range_table = &range_digital;
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s->maxdata = 1;
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s->insn_bits = subdev_8255_insn;
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s->insn_config = subdev_8255_insn_config;
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subdev_8255_do_config(dev, s);
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return 0;
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}
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/**
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* subdev_8255_init - initialize DIO subdevice for driving I/O mapped 8255
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* @dev: comedi device owning subdevice
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* @s: comedi subdevice to initialize
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* @io: (optional) register I/O call-back function
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* @regbase: offset of 8255 registers from dev->iobase, or call-back context
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*
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* Initializes a comedi subdevice as a DIO subdevice driving an 8255 chip.
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*
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* If the optional I/O call-back function is provided, its prototype is of
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* the following form:
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*
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* int my_8255_callback(struct comedi_device *dev, int dir, int port,
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* int data, unsigned long regbase);
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*
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* where 'dev', and 'regbase' match the values passed to this function,
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* 'port' is the 8255 port number 0 to 3 (including the control port), 'dir'
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* is the direction (0 for read, 1 for write) and 'data' is the value to be
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* written. It should return 0 if writing or the value read if reading.
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*
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* If the optional I/O call-back function is not provided, an internal
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* call-back function is used which uses consecutive I/O port addresses
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* starting at dev->iobase + regbase.
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*
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* Return: -ENOMEM if failed to allocate memory, zero on success.
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*/
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int subdev_8255_init(struct comedi_device *dev, struct comedi_subdevice *s,
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int (*io)(struct comedi_device *dev, int dir, int port,
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int data, unsigned long regbase),
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unsigned long regbase)
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{
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return __subdev_8255_init(dev, s, io, regbase, false);
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}
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EXPORT_SYMBOL_GPL(subdev_8255_init);
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/**
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* subdev_8255_mm_init - initialize DIO subdevice for driving mmio-mapped 8255
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* @dev: comedi device owning subdevice
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* @s: comedi subdevice to initialize
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* @io: (optional) register I/O call-back function
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* @regbase: offset of 8255 registers from dev->mmio, or call-back context
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*
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* Initializes a comedi subdevice as a DIO subdevice driving an 8255 chip.
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*
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* If the optional I/O call-back function is provided, its prototype is of
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* the following form:
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*
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* int my_8255_callback(struct comedi_device *dev, int dir, int port,
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* int data, unsigned long regbase);
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*
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* where 'dev', and 'regbase' match the values passed to this function,
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* 'port' is the 8255 port number 0 to 3 (including the control port), 'dir'
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* is the direction (0 for read, 1 for write) and 'data' is the value to be
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* written. It should return 0 if writing or the value read if reading.
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*
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* If the optional I/O call-back function is not provided, an internal
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* call-back function is used which uses consecutive MMIO virtual addresses
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* starting at dev->mmio + regbase.
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*
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* Return: -ENOMEM if failed to allocate memory, zero on success.
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*/
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int subdev_8255_mm_init(struct comedi_device *dev, struct comedi_subdevice *s,
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int (*io)(struct comedi_device *dev, int dir, int port,
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int data, unsigned long regbase),
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unsigned long regbase)
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{
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return __subdev_8255_init(dev, s, io, regbase, true);
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}
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EXPORT_SYMBOL_GPL(subdev_8255_mm_init);
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/*
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* Start of the 8255 standalone device
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*/
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static int dev_8255_attach(struct comedi_device *dev,
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struct comedi_devconfig *it)
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{
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@ -324,14 +109,14 @@ static int dev_8255_attach(struct comedi_device *dev,
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static void dev_8255_detach(struct comedi_device *dev)
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{
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struct comedi_subdevice *s;
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struct subdev_8255_private *spriv;
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int i;
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for (i = 0; i < dev->n_subdevices; i++) {
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s = &dev->subdevices[i];
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if (s->type != COMEDI_SUBD_UNUSED) {
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spriv = s->private;
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release_region(spriv->regbase, I8255_SIZE);
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unsigned long regbase = subdev_8255_regbase(s);
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release_region(regbase, I8255_SIZE);
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}
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}
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}
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@ -345,5 +130,5 @@ static struct comedi_driver dev_8255_driver = {
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module_comedi_driver(dev_8255_driver);
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MODULE_AUTHOR("Comedi http://www.comedi.org");
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MODULE_DESCRIPTION("Comedi low-level driver");
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MODULE_DESCRIPTION("Comedi driver for standalone 8255 devices");
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MODULE_LICENSE("GPL");
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@ -46,4 +46,6 @@ int subdev_8255_mm_init(struct comedi_device *dev, struct comedi_subdevice *s,
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int data, unsigned long regbase),
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unsigned long regbase);
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unsigned long subdev_8255_regbase(struct comedi_subdevice *s);
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#endif
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@ -139,7 +139,8 @@ obj-$(CONFIG_COMEDI_NI_TIOCMD) += ni_tiocmd.o
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obj-$(CONFIG_COMEDI_NI_LABPC) += ni_labpc_common.o
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obj-$(CONFIG_COMEDI_NI_LABPC_ISADMA) += ni_labpc_isadma.o
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obj-$(CONFIG_COMEDI_8255) += 8255.o
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obj-$(CONFIG_COMEDI_8255) += comedi_8255.o
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obj-$(CONFIG_COMEDI_8255_SA) += 8255.o
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obj-$(CONFIG_COMEDI_AMPLC_DIO200) += amplc_dio200_common.o
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obj-$(CONFIG_COMEDI_AMPLC_PC236) += amplc_pc236_common.o
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obj-$(CONFIG_COMEDI_DAS08) += das08.o
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@ -0,0 +1,285 @@
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/*
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* comedi_8255.c
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* Generic 8255 digital I/O support
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*
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* Split from the Comedi "8255" driver module.
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*
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* COMEDI - Linux Control and Measurement Device Interface
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* Copyright (C) 1998 David A. Schleef <ds@schleef.org>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*/
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/*
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* Module: comedi_8255
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* Description: Generic 8255 support
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* Author: ds
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* Updated: Fri, 22 May 2015 12:14:17 +0000
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* Status: works
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*
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* This module is not used directly by end-users. Rather, it is used by
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* other drivers to provide support for an 8255 "Programmable Peripheral
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* Interface" (PPI) chip.
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*
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* The classic in digital I/O. The 8255 appears in Comedi as a single
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* digital I/O subdevice with 24 channels. The channel 0 corresponds to
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* the 8255's port A, bit 0; channel 23 corresponds to port C, bit 7.
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* Direction configuration is done in blocks, with channels 0-7, 8-15,
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* 16-19, and 20-23 making up the 4 blocks. The only 8255 mode
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* supported is mode 0.
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*/
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#include <linux/module.h>
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#include "../comedidev.h"
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#include "8255.h"
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struct subdev_8255_private {
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unsigned long regbase;
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int (*io)(struct comedi_device *dev, int dir, int port, int data,
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unsigned long regbase);
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};
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static int subdev_8255_io(struct comedi_device *dev,
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int dir, int port, int data, unsigned long regbase)
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{
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if (dir) {
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outb(data, dev->iobase + regbase + port);
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return 0;
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}
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return inb(dev->iobase + regbase + port);
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}
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static int subdev_8255_mmio(struct comedi_device *dev,
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int dir, int port, int data, unsigned long regbase)
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{
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if (dir) {
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writeb(data, dev->mmio + regbase + port);
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return 0;
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}
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return readb(dev->mmio + regbase + port);
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}
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static int subdev_8255_insn(struct comedi_device *dev,
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struct comedi_subdevice *s,
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struct comedi_insn *insn,
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unsigned int *data)
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{
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struct subdev_8255_private *spriv = s->private;
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unsigned long regbase = spriv->regbase;
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unsigned int mask;
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unsigned int v;
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mask = comedi_dio_update_state(s, data);
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if (mask) {
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if (mask & 0xff)
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spriv->io(dev, 1, I8255_DATA_A_REG,
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s->state & 0xff, regbase);
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if (mask & 0xff00)
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spriv->io(dev, 1, I8255_DATA_B_REG,
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(s->state >> 8) & 0xff, regbase);
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if (mask & 0xff0000)
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spriv->io(dev, 1, I8255_DATA_C_REG,
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(s->state >> 16) & 0xff, regbase);
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}
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v = spriv->io(dev, 0, I8255_DATA_A_REG, 0, regbase);
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v |= (spriv->io(dev, 0, I8255_DATA_B_REG, 0, regbase) << 8);
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v |= (spriv->io(dev, 0, I8255_DATA_C_REG, 0, regbase) << 16);
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data[1] = v;
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return insn->n;
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}
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static void subdev_8255_do_config(struct comedi_device *dev,
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struct comedi_subdevice *s)
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{
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struct subdev_8255_private *spriv = s->private;
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unsigned long regbase = spriv->regbase;
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int config;
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config = I8255_CTRL_CW;
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/* 1 in io_bits indicates output, 1 in config indicates input */
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if (!(s->io_bits & 0x0000ff))
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config |= I8255_CTRL_A_IO;
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if (!(s->io_bits & 0x00ff00))
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config |= I8255_CTRL_B_IO;
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if (!(s->io_bits & 0x0f0000))
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config |= I8255_CTRL_C_LO_IO;
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if (!(s->io_bits & 0xf00000))
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config |= I8255_CTRL_C_HI_IO;
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spriv->io(dev, 1, I8255_CTRL_REG, config, regbase);
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}
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static int subdev_8255_insn_config(struct comedi_device *dev,
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struct comedi_subdevice *s,
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struct comedi_insn *insn,
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unsigned int *data)
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{
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unsigned int chan = CR_CHAN(insn->chanspec);
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unsigned int mask;
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int ret;
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if (chan < 8)
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mask = 0x0000ff;
|
||||
else if (chan < 16)
|
||||
mask = 0x00ff00;
|
||||
else if (chan < 20)
|
||||
mask = 0x0f0000;
|
||||
else
|
||||
mask = 0xf00000;
|
||||
|
||||
ret = comedi_dio_insn_config(dev, s, insn, data, mask);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
subdev_8255_do_config(dev, s);
|
||||
|
||||
return insn->n;
|
||||
}
|
||||
|
||||
static int __subdev_8255_init(struct comedi_device *dev,
|
||||
struct comedi_subdevice *s,
|
||||
int (*io)(struct comedi_device *dev,
|
||||
int dir, int port, int data,
|
||||
unsigned long regbase),
|
||||
unsigned long regbase,
|
||||
bool is_mmio)
|
||||
{
|
||||
struct subdev_8255_private *spriv;
|
||||
|
||||
spriv = comedi_alloc_spriv(s, sizeof(*spriv));
|
||||
if (!spriv)
|
||||
return -ENOMEM;
|
||||
|
||||
if (io)
|
||||
spriv->io = io;
|
||||
else if (is_mmio)
|
||||
spriv->io = subdev_8255_mmio;
|
||||
else
|
||||
spriv->io = subdev_8255_io;
|
||||
spriv->regbase = regbase;
|
||||
|
||||
s->type = COMEDI_SUBD_DIO;
|
||||
s->subdev_flags = SDF_READABLE | SDF_WRITABLE;
|
||||
s->n_chan = 24;
|
||||
s->range_table = &range_digital;
|
||||
s->maxdata = 1;
|
||||
s->insn_bits = subdev_8255_insn;
|
||||
s->insn_config = subdev_8255_insn_config;
|
||||
|
||||
subdev_8255_do_config(dev, s);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* subdev_8255_init - initialize DIO subdevice for driving I/O mapped 8255
|
||||
* @dev: comedi device owning subdevice
|
||||
* @s: comedi subdevice to initialize
|
||||
* @io: (optional) register I/O call-back function
|
||||
* @regbase: offset of 8255 registers from dev->iobase, or call-back context
|
||||
*
|
||||
* Initializes a comedi subdevice as a DIO subdevice driving an 8255 chip.
|
||||
*
|
||||
* If the optional I/O call-back function is provided, its prototype is of
|
||||
* the following form:
|
||||
*
|
||||
* int my_8255_callback(struct comedi_device *dev, int dir, int port,
|
||||
* int data, unsigned long regbase);
|
||||
*
|
||||
* where 'dev', and 'regbase' match the values passed to this function,
|
||||
* 'port' is the 8255 port number 0 to 3 (including the control port), 'dir'
|
||||
* is the direction (0 for read, 1 for write) and 'data' is the value to be
|
||||
* written. It should return 0 if writing or the value read if reading.
|
||||
*
|
||||
* If the optional I/O call-back function is not provided, an internal
|
||||
* call-back function is used which uses consecutive I/O port addresses
|
||||
* starting at dev->iobase + regbase.
|
||||
*
|
||||
* Return: -ENOMEM if failed to allocate memory, zero on success.
|
||||
*/
|
||||
int subdev_8255_init(struct comedi_device *dev, struct comedi_subdevice *s,
|
||||
int (*io)(struct comedi_device *dev, int dir, int port,
|
||||
int data, unsigned long regbase),
|
||||
unsigned long regbase)
|
||||
{
|
||||
return __subdev_8255_init(dev, s, io, regbase, false);
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(subdev_8255_init);
|
||||
|
||||
/**
|
||||
* subdev_8255_mm_init - initialize DIO subdevice for driving mmio-mapped 8255
|
||||
* @dev: comedi device owning subdevice
|
||||
* @s: comedi subdevice to initialize
|
||||
* @io: (optional) register I/O call-back function
|
||||
* @regbase: offset of 8255 registers from dev->mmio, or call-back context
|
||||
*
|
||||
* Initializes a comedi subdevice as a DIO subdevice driving an 8255 chip.
|
||||
*
|
||||
* If the optional I/O call-back function is provided, its prototype is of
|
||||
* the following form:
|
||||
*
|
||||
* int my_8255_callback(struct comedi_device *dev, int dir, int port,
|
||||
* int data, unsigned long regbase);
|
||||
*
|
||||
* where 'dev', and 'regbase' match the values passed to this function,
|
||||
* 'port' is the 8255 port number 0 to 3 (including the control port), 'dir'
|
||||
* is the direction (0 for read, 1 for write) and 'data' is the value to be
|
||||
* written. It should return 0 if writing or the value read if reading.
|
||||
*
|
||||
* If the optional I/O call-back function is not provided, an internal
|
||||
* call-back function is used which uses consecutive MMIO virtual addresses
|
||||
* starting at dev->mmio + regbase.
|
||||
*
|
||||
* Return: -ENOMEM if failed to allocate memory, zero on success.
|
||||
*/
|
||||
int subdev_8255_mm_init(struct comedi_device *dev, struct comedi_subdevice *s,
|
||||
int (*io)(struct comedi_device *dev, int dir, int port,
|
||||
int data, unsigned long regbase),
|
||||
unsigned long regbase)
|
||||
{
|
||||
return __subdev_8255_init(dev, s, io, regbase, true);
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(subdev_8255_mm_init);
|
||||
|
||||
/**
|
||||
* subdev_8255_regbase - get offset of 8255 registers or call-back context
|
||||
* @s: comedi subdevice
|
||||
*
|
||||
* Returns the 'regbase' parameter that was previously passed to to
|
||||
* subdev_8255_init() or subdev_8255_mm_init() to set up the subdevice.
|
||||
* Only valid if the subdevice was set up successfully.
|
||||
*/
|
||||
unsigned long subdev_8255_regbase(struct comedi_subdevice *s)
|
||||
{
|
||||
struct subdev_8255_private *spriv = s->private;
|
||||
|
||||
return spriv->regbase;
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(subdev_8255_regbase);
|
||||
|
||||
static int __init comedi_8255_module_init(void)
|
||||
{
|
||||
return 0;
|
||||
}
|
||||
module_init(comedi_8255_module_init);
|
||||
|
||||
static void __exit comedi_8255_module_exit(void)
|
||||
{
|
||||
}
|
||||
module_exit(comedi_8255_module_exit);
|
||||
|
||||
MODULE_AUTHOR("Comedi http://www.comedi.org");
|
||||
MODULE_DESCRIPTION("Comedi: Generic 8255 digital I/O support");
|
||||
MODULE_LICENSE("GPL");
|
||||
Loading…
Reference in New Issue