drivers/comedi/drivers/comedi_8255.c - SHIFTPHONES/mainline/linux - Gitiles

 // SPDX-License-Identifier: GPL-2.0+
 /*
  * comedi_8255.c
  * Generic 8255 digital I/O support
  *
  * Split from the Comedi "8255" driver module.
  *
  * COMEDI - Linux Control and Measurement Device Interface
  * Copyright (C) 1998 David A. Schleef <ds@schleef.org>
  */

 /*
  * Module: comedi_8255
  * Description: Generic 8255 support
  * Author: ds
  * Updated: Fri, 22 May 2015 12:14:17 +0000
  * Status: works
  *
  * This module is not used directly by end-users.  Rather, it is used by
  * other drivers to provide support for an 8255 "Programmable Peripheral
  * Interface" (PPI) chip.
  *
  * The classic in digital I/O.  The 8255 appears in Comedi as a single
  * digital I/O subdevice with 24 channels.  The channel 0 corresponds to
  * the 8255's port A, bit 0; channel 23 corresponds to port C, bit 7.
  * Direction configuration is done in blocks, with channels 0-7, 8-15,
  * 16-19, and 20-23 making up the 4 blocks.  The only 8255 mode
  * supported is mode 0.
  */

 #include <linux/module.h>
 #include <linux/comedi/comedidev.h>
 #include <linux/comedi/comedi_8255.h>

 struct subdev_8255_private {
 	unsigned long regbase;
 	int (*io)(struct comedi_device *dev, int dir, int port, int data,
 		  unsigned long regbase);
 };

 static int subdev_8255_io(struct comedi_device *dev,
 			  int dir, int port, int data, unsigned long regbase)
 {
 	if (dir) {
 		outb(data, dev->iobase + regbase + port);
 		return 0;
 	}
 	return inb(dev->iobase + regbase + port);
 }

 static int subdev_8255_mmio(struct comedi_device *dev,
 			    int dir, int port, int data, unsigned long regbase)
 {
 	if (dir) {
 		writeb(data, dev->mmio + regbase + port);
 		return 0;
 	}
 	return readb(dev->mmio + regbase + port);
 }

 static int subdev_8255_insn(struct comedi_device *dev,
 			    struct comedi_subdevice *s,
 			    struct comedi_insn *insn,
 			    unsigned int *data)
 {
 	struct subdev_8255_private *spriv = s->private;
 	unsigned long regbase = spriv->regbase;
 	unsigned int mask;
 	unsigned int v;

 	mask = comedi_dio_update_state(s, data);
 	if (mask) {
 		if (mask & 0xff)
 			spriv->io(dev, 1, I8255_DATA_A_REG,
 				  s->state & 0xff, regbase);
 		if (mask & 0xff00)
 			spriv->io(dev, 1, I8255_DATA_B_REG,
 				  (s->state >> 8) & 0xff, regbase);
 		if (mask & 0xff0000)
 			spriv->io(dev, 1, I8255_DATA_C_REG,
 				  (s->state >> 16) & 0xff, regbase);
 	}

 	v = spriv->io(dev, 0, I8255_DATA_A_REG, 0, regbase);
 	v |= (spriv->io(dev, 0, I8255_DATA_B_REG, 0, regbase) << 8);
 	v |= (spriv->io(dev, 0, I8255_DATA_C_REG, 0, regbase) << 16);

 	data[1] = v;

 	return insn->n;
 }

 static void subdev_8255_do_config(struct comedi_device *dev,
 				  struct comedi_subdevice *s)
 {
 	struct subdev_8255_private *spriv = s->private;
 	unsigned long regbase = spriv->regbase;
 	int config;

 	config = I8255_CTRL_CW;
 	/* 1 in io_bits indicates output, 1 in config indicates input */
 	if (!(s->io_bits & 0x0000ff))
 		config |= I8255_CTRL_A_IO;
 	if (!(s->io_bits & 0x00ff00))
 		config |= I8255_CTRL_B_IO;
 	if (!(s->io_bits & 0x0f0000))
 		config |= I8255_CTRL_C_LO_IO;
 	if (!(s->io_bits & 0xf00000))
 		config |= I8255_CTRL_C_HI_IO;

 	spriv->io(dev, 1, I8255_CTRL_REG, config, regbase);
 }

 static int subdev_8255_insn_config(struct comedi_device *dev,
 				   struct comedi_subdevice *s,
 				   struct comedi_insn *insn,
 				   unsigned int *data)
 {
 	unsigned int chan = CR_CHAN(insn->chanspec);
 	unsigned int mask;
 	int ret;

 	if (chan < 8)
 		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
  * 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 https://www.comedi.org");
 MODULE_DESCRIPTION("Comedi: Generic 8255 digital I/O support");
 MODULE_LICENSE("GPL");
	// SPDX-License-Identifier: GPL-2.0+
	/*
	* comedi_8255.c
	* Generic 8255 digital I/O support
	*
	* Split from the Comedi "8255" driver module.
	*
	* COMEDI - Linux Control and Measurement Device Interface
	* Copyright (C) 1998 David A. Schleef <ds@schleef.org>
	*/

	/*
	* Module: comedi_8255
	* Description: Generic 8255 support
	* Author: ds
	* Updated: Fri, 22 May 2015 12:14:17 +0000
	* Status: works
	*
	* This module is not used directly by end-users. Rather, it is used by
	* other drivers to provide support for an 8255 "Programmable Peripheral
	* Interface" (PPI) chip.
	*
	* The classic in digital I/O. The 8255 appears in Comedi as a single
	* digital I/O subdevice with 24 channels. The channel 0 corresponds to
	* the 8255's port A, bit 0; channel 23 corresponds to port C, bit 7.
	* Direction configuration is done in blocks, with channels 0-7, 8-15,
	* 16-19, and 20-23 making up the 4 blocks. The only 8255 mode
	* supported is mode 0.
	*/

	#include <linux/module.h>
	#include <linux/comedi/comedidev.h>
	#include <linux/comedi/comedi_8255.h>

	struct subdev_8255_private {
	unsigned long regbase;
	int (io)(struct comedi_device dev, int dir, int port, int data,
	unsigned long regbase);
	};

	static int subdev_8255_io(struct comedi_device *dev,
	int dir, int port, int data, unsigned long regbase)
	{
	if (dir) {
	outb(data, dev->iobase + regbase + port);
	return 0;
	}
	return inb(dev->iobase + regbase + port);
	}

	static int subdev_8255_mmio(struct comedi_device *dev,
	int dir, int port, int data, unsigned long regbase)
	{
	if (dir) {
	writeb(data, dev->mmio + regbase + port);
	return 0;
	}
	return readb(dev->mmio + regbase + port);
	}

	static int subdev_8255_insn(struct comedi_device *dev,
	struct comedi_subdevice *s,
	struct comedi_insn *insn,
	unsigned int *data)
	{
	struct subdev_8255_private *spriv = s->private;
	unsigned long regbase = spriv->regbase;
	unsigned int mask;
	unsigned int v;

	mask = comedi_dio_update_state(s, data);
	if (mask) {
	if (mask & 0xff)
	spriv->io(dev, 1, I8255_DATA_A_REG,
	s->state & 0xff, regbase);
	if (mask & 0xff00)
	spriv->io(dev, 1, I8255_DATA_B_REG,
	(s->state >> 8) & 0xff, regbase);
	if (mask & 0xff0000)
	spriv->io(dev, 1, I8255_DATA_C_REG,
	(s->state >> 16) & 0xff, regbase);
	}

	v = spriv->io(dev, 0, I8255_DATA_A_REG, 0, regbase);
	v \|= (spriv->io(dev, 0, I8255_DATA_B_REG, 0, regbase) << 8);
	v \|= (spriv->io(dev, 0, I8255_DATA_C_REG, 0, regbase) << 16);

	data[1] = v;

	return insn->n;
	}

	static void subdev_8255_do_config(struct comedi_device *dev,
	struct comedi_subdevice *s)
	{
	struct subdev_8255_private *spriv = s->private;
	unsigned long regbase = spriv->regbase;
	int config;

	config = I8255_CTRL_CW;
	/* 1 in io_bits indicates output, 1 in config indicates input */
	if (!(s->io_bits & 0x0000ff))
	config \|= I8255_CTRL_A_IO;
	if (!(s->io_bits & 0x00ff00))
	config \|= I8255_CTRL_B_IO;
	if (!(s->io_bits & 0x0f0000))
	config \|= I8255_CTRL_C_LO_IO;
	if (!(s->io_bits & 0xf00000))
	config \|= I8255_CTRL_C_HI_IO;

	spriv->io(dev, 1, I8255_CTRL_REG, config, regbase);
	}

	static int subdev_8255_insn_config(struct comedi_device *dev,
	struct comedi_subdevice *s,
	struct comedi_insn *insn,
	unsigned int *data)
	{
	unsigned int chan = CR_CHAN(insn->chanspec);
	unsigned int mask;
	int ret;

	if (chan < 8)
	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
	* 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 https://www.comedi.org");
	MODULE_DESCRIPTION("Comedi: Generic 8255 digital I/O support");
	MODULE_LICENSE("GPL");