/*
    comedi/drivers/amplc_pc263.c
    Driver for Amplicon PC263 and PCI263 relay boards.

    Copyright (C) 2002 MEV Ltd. <http://www.mev.co.uk/>

    COMEDI - Linux Control and Measurement Device Interface
    Copyright (C) 2000 David A. Schleef <ds@schleef.org>

    This program 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.

    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.

    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., 675 Mass Ave, Cambridge, MA 02139, USA.

*/
/*
Driver: amplc_pc263
Description: Amplicon PC263, PCI263
Author: Ian Abbott <abbotti@mev.co.uk>
Devices: [Amplicon] PC263 (pc263), PCI263 (pci263 or amplc_pc263)
Updated: Wed, 22 Oct 2008 14:10:53 +0100
Status: works

Configuration options - PC263:
  [0] - I/O port base address

Configuration options - PCI263:
  [0] - PCI bus of device (optional)
  [1] - PCI slot of device (optional)
  If bus/slot is not specified, the first available PCI device will be
  used.

Each board appears as one subdevice, with 16 digital outputs, each
connected to a reed-relay. Relay contacts are closed when output is 1.
The state of the outputs can be read.
*/

#include <linux/pci.h>

#include "../comedidev.h"

#define PC263_DRIVER_NAME	"amplc_pc263"

#define DO_ISA	IS_ENABLED(CONFIG_COMEDI_AMPLC_PC263_ISA)
#define DO_PCI	IS_ENABLED(CONFIG_COMEDI_AMPLC_PC263_PCI)

/* PCI263 PCI configuration register information */
#define PCI_DEVICE_ID_AMPLICON_PCI263 0x000c
#define PCI_DEVICE_ID_INVALID 0xffff

/* PC263 / PCI263 registers */
#define PC263_IO_SIZE	2

/*
 * Board descriptions for Amplicon PC263 / PCI263.
 */

enum pc263_bustype { isa_bustype, pci_bustype };
enum pc263_model { pc263_model, pci263_model, anypci_model };

struct pc263_board {
	const char *name;
	unsigned short devid;
	enum pc263_bustype bustype;
	enum pc263_model model;
};
static const struct pc263_board pc263_boards[] = {
#if DO_ISA
	{
		.name = "pc263",
		.bustype = isa_bustype,
		.model = pc263_model,
	},
#endif
#if DO_PCI
	{
		.name = "pci263",
		.devid = PCI_DEVICE_ID_AMPLICON_PCI263,
		.bustype = pci_bustype,
		.model = pci263_model,
	},
	{
		.name = PC263_DRIVER_NAME,
		.devid = PCI_DEVICE_ID_INVALID,
		.bustype = pci_bustype,
		.model = anypci_model,	/* wildcard */
	},
#endif
};

/* test if ISA supported and this is an ISA board */
static inline bool is_isa_board(const struct pc263_board *board)
{
	return DO_ISA && board->bustype == isa_bustype;
}

/* test if PCI supported and this is a PCI board */
static inline bool is_pci_board(const struct pc263_board *board)
{
	return DO_PCI && board->bustype == pci_bustype;
}

/*
 * This function looks for a board matching the supplied PCI device.
 */
static const struct pc263_board *pc263_find_pci_board(struct pci_dev *pci_dev)
{
	unsigned int i;

	for (i = 0; i < ARRAY_SIZE(pc263_boards); i++)
		if (is_pci_board(&pc263_boards[i]) &&
		    pci_dev->device == pc263_boards[i].devid)
			return &pc263_boards[i];
	return NULL;
}


/*
 * This function looks for a PCI device matching the requested board name,
 * bus and slot.
 */
static struct pci_dev *pc263_find_pci_dev(struct comedi_device *dev,
					  struct comedi_devconfig *it)
{
	const struct pc263_board *thisboard = comedi_board(dev);
	struct pci_dev *pci_dev = NULL;
	int bus = it->options[0];
	int slot = it->options[1];

	for_each_pci_dev(pci_dev) {
		if (bus || slot) {
			if (bus != pci_dev->bus->number ||
			    slot != PCI_SLOT(pci_dev->devfn))
				continue;
		}
		if (pci_dev->vendor != PCI_VENDOR_ID_AMPLICON)
			continue;

		if (thisboard->model == anypci_model) {
			/* Wildcard board matches any supported PCI board. */
			const struct pc263_board *foundboard;

			foundboard = pc263_find_pci_board(pci_dev);
			if (foundboard == NULL)
				continue;
			/* Replace wildcard board_ptr. */
			dev->board_ptr = thisboard = foundboard;
		} else {
			/* Match specific model name. */
			if (pci_dev->device != thisboard->devid)
				continue;
		}
		return pci_dev;
	}
	dev_err(dev->class_dev,
		"No supported board found! (req. bus %d, slot %d)\n",
		bus, slot);
	return NULL;
}
/*
 * This function checks and requests an I/O region, reporting an error
 * if there is a conflict.
 */
static int pc263_request_region(struct comedi_device *dev, unsigned long from,
				unsigned long extent)
{
	if (!from || !request_region(from, extent, PC263_DRIVER_NAME)) {
		dev_err(dev->class_dev, "I/O port conflict (%#lx,%lu)!\n",
			from, extent);
		return -EIO;
	}
	return 0;
}

static int pc263_do_insn_bits(struct comedi_device *dev,
			      struct comedi_subdevice *s,
			      struct comedi_insn *insn, unsigned int *data)
{
	/* The insn data is a mask in data[0] and the new data
	 * in data[1], each channel cooresponding to a bit. */
	if (data[0]) {
		s->state &= ~data[0];
		s->state |= data[0] & data[1];
		/* Write out the new digital output lines */
		outb(s->state & 0xFF, dev->iobase);
		outb(s->state >> 8, dev->iobase + 1);
	}
	return insn->n;
}

static void pc263_report_attach(struct comedi_device *dev)
{
	const struct pc263_board *thisboard = comedi_board(dev);
	struct pci_dev *pcidev = comedi_to_pci_dev(dev);
	char tmpbuf[40];

	if (is_isa_board(thisboard))
		snprintf(tmpbuf, sizeof(tmpbuf), "(base %#lx) ", dev->iobase);
	else if (is_pci_board(thisboard))
		snprintf(tmpbuf, sizeof(tmpbuf), "(pci %s) ",
			 pci_name(pcidev));
	else
		tmpbuf[0] = '\0';
	dev_info(dev->class_dev, "%s %sattached\n", dev->board_name, tmpbuf);
}

static int pc263_common_attach(struct comedi_device *dev, unsigned long iobase)
{
	const struct pc263_board *thisboard = comedi_board(dev);
	struct comedi_subdevice *s;
	int ret;

	dev->board_name = thisboard->name;
	dev->iobase = iobase;

	ret = comedi_alloc_subdevices(dev, 1);
	if (ret)
		return ret;

	s = &dev->subdevices[0];
	/* digital output subdevice */
	s->type = COMEDI_SUBD_DO;
	s->subdev_flags = SDF_READABLE | SDF_WRITABLE;
	s->n_chan = 16;
	s->maxdata = 1;
	s->range_table = &range_digital;
	s->insn_bits = pc263_do_insn_bits;
	/* read initial relay state */
	s->state = inb(dev->iobase) | (inb(dev->iobase + 1) << 8);

	pc263_report_attach(dev);
	return 1;
}

static int pc263_pci_common_attach(struct comedi_device *dev,
				   struct pci_dev *pci_dev)
{
	unsigned long iobase;
	int ret;

	comedi_set_hw_dev(dev, &pci_dev->dev);

	ret = comedi_pci_enable(pci_dev, PC263_DRIVER_NAME);
	if (ret < 0) {
		dev_err(dev->class_dev,
			"error! cannot enable PCI device and request regions!\n");
		return ret;
	}
	iobase = pci_resource_start(pci_dev, 2);
	return pc263_common_attach(dev, iobase);
}

/*
 * Attach is called by the Comedi core to configure the driver
 * for a particular board.  If you specified a board_name array
 * in the driver structure, dev->board_ptr contains that
 * address.
 */
static int pc263_attach(struct comedi_device *dev, struct comedi_devconfig *it)
{
	const struct pc263_board *thisboard = comedi_board(dev);
	int ret;

	dev_info(dev->class_dev, PC263_DRIVER_NAME ": attach\n");

	/* Process options and reserve resources according to bus type. */
	if (is_isa_board(thisboard)) {
		unsigned long iobase = it->options[0];
		ret = pc263_request_region(dev, iobase, PC263_IO_SIZE);
		if (ret < 0)
			return ret;
		return pc263_common_attach(dev, iobase);
	} else if (is_pci_board(thisboard)) {
		struct pci_dev *pci_dev;

		pci_dev = pc263_find_pci_dev(dev, it);
		if (!pci_dev)
			return -EIO;
		return pc263_pci_common_attach(dev, pci_dev);
	} else {
		dev_err(dev->class_dev, PC263_DRIVER_NAME
			": BUG! cannot determine board type!\n");
		return -EINVAL;
	}
}

/*
 * The auto_attach hook is called at PCI probe time via
 * comedi_pci_auto_config().  dev->board_ptr is NULL on entry.
 * There should be a board entry matching the supplied PCI device.
 */
static int pc263_auto_attach(struct comedi_device *dev,
				       unsigned long context_unused)
{
	struct pci_dev *pci_dev;

	if (!DO_PCI)
		return -EINVAL;

	pci_dev = comedi_to_pci_dev(dev);
	dev_info(dev->class_dev, PC263_DRIVER_NAME ": attach pci %s\n",
		 pci_name(pci_dev));
	dev->board_ptr = pc263_find_pci_board(pci_dev);
	if (dev->board_ptr == NULL) {
		dev_err(dev->class_dev, "BUG! cannot determine board type!\n");
		return -EINVAL;
	}
	/*
	 * Need to 'get' the PCI device to match the 'put' in pc263_detach().
	 * TODO: Remove the pci_dev_get() and matching pci_dev_put() once
	 * support for manual attachment of PCI devices via pc263_attach()
	 * has been removed.
	 */
	pci_dev_get(pci_dev);
	return pc263_pci_common_attach(dev, pci_dev);
}

static void pc263_detach(struct comedi_device *dev)
{
	const struct pc263_board *thisboard = comedi_board(dev);

	if (!thisboard)
		return;
	if (is_isa_board(thisboard)) {
		if (dev->iobase)
			release_region(dev->iobase, PC263_IO_SIZE);
	} else if (is_pci_board(thisboard)) {
		struct pci_dev *pcidev = comedi_to_pci_dev(dev);
		if (pcidev) {
			if (dev->iobase)
				comedi_pci_disable(pcidev);
			pci_dev_put(pcidev);
		}
	}
}

/*
 * The struct comedi_driver structure tells the Comedi core module
 * which functions to call to configure/deconfigure (attach/detach)
 * the board, and also about the kernel module that contains
 * the device code.
 */
static struct comedi_driver amplc_pc263_driver = {
	.driver_name = PC263_DRIVER_NAME,
	.module = THIS_MODULE,
	.attach = pc263_attach,
	.auto_attach = pc263_auto_attach,
	.detach = pc263_detach,
	.board_name = &pc263_boards[0].name,
	.offset = sizeof(struct pc263_board),
	.num_names = ARRAY_SIZE(pc263_boards),
};

#if DO_PCI
static DEFINE_PCI_DEVICE_TABLE(pc263_pci_table) = {
	{ PCI_DEVICE(PCI_VENDOR_ID_AMPLICON, PCI_DEVICE_ID_AMPLICON_PCI263) },
	{0}
};
MODULE_DEVICE_TABLE(pci, pc263_pci_table);

static int amplc_pc263_pci_probe(struct pci_dev *dev,
						  const struct pci_device_id
						  *ent)
{
	return comedi_pci_auto_config(dev, &amplc_pc263_driver);
}

static struct pci_driver amplc_pc263_pci_driver = {
	.name = PC263_DRIVER_NAME,
	.id_table = pc263_pci_table,
	.probe = &amplc_pc263_pci_probe,
	.remove		= comedi_pci_auto_unconfig,
};
module_comedi_pci_driver(amplc_pc263_driver, amplc_pc263_pci_driver);
#else
module_comedi_driver(amplc_pc263_driver);
#endif

MODULE_AUTHOR("Comedi http://www.comedi.org");
MODULE_DESCRIPTION("Comedi low-level driver");
MODULE_LICENSE("GPL");