Release 4.7 drivers/i2c/busses/i2c-elektor.c

/* ------------------------------------------------------------------------- */
/* i2c-elektor.c i2c-hw access for PCF8584 style isa bus adaptes             */
/* ------------------------------------------------------------------------- */
/*   Copyright (C) 1995-97 Simon G. Vogl
                   1998-99 Hans Berglund

    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.                             */
/* ------------------------------------------------------------------------- */

/* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and even
   Frodo Looijaard <frodol@dds.nl> */

/* Partially rewriten by Oleg I. Vdovikin for mmapped support of
   for Alpha Processor Inc. UP-2000(+) boards */

#include <linux/kernel.h>
#include <linux/ioport.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/pci.h>
#include <linux/wait.h>

#include <linux/isa.h>
#include <linux/i2c.h>
#include <linux/i2c-algo-pcf.h>
#include <linux/io.h>

#include <asm/irq.h>

#include "../algos/i2c-algo-pcf.h"


#define DEFAULT_BASE 0x330


static int base;

static u8 __iomem *base_iomem;


static int irq;

static int clock  = 0x1c;

static int own    = 0x55;

static int mmapped;

/* vdovikin: removed static struct i2c_pcf_isa gpi; code -
  this module in real supports only one device, due to missing arguments
  in some functions, called from the algo-pcf module. Sometimes it's
  need to be rewriten - but for now just remove this for simpler reading */


static wait_queue_head_t pcf_wait;

static int pcf_pending;

static spinlock_t lock;


static struct i2c_adapter pcf_isa_ops;

/* ----- local functions ---------------------------------------------- */



static void pcf_isa_setbyte(void *data, int ctl, int val)
{
	u8 __iomem *address = ctl ? (base_iomem + 1) : base_iomem;

	/* enable irq if any specified for serial operation */
	if (ctl && irq && (val & I2C_PCF_ESO)) {
		val |= I2C_PCF_ENI;
	}

	pr_debug("%s: Write %p 0x%02X\n", pcf_isa_ops.name, address, val);
	iowrite8(val, address);
#ifdef __alpha__
	/* API UP2000 needs some hardware fudging to make the write stick */
	iowrite8(val, address);
#endif
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
pre-git
pre-git
43
51.81%
2
28.57%
stig telfer
stig telfer
18
21.69%
2
28.57%
linus torvalds
linus torvalds
14
16.87%
1
14.29%
albert cranford
albert cranford
7
8.43%
1
14.29%
greg kroah-hartman
greg kroah-hartman
1
1.20%
1
14.29%
Total
83
100.00%
7
100.00%



static int pcf_isa_getbyte(void *data, int ctl)
{
	u8 __iomem *address = ctl ? (base_iomem + 1) : base_iomem;
	int val = ioread8(address);

	pr_debug("%s: Read %p 0x%02X\n", pcf_isa_ops.name, address, val);
	return (val);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
pre-git
pre-git
27
50.00%
1
20.00%
linus torvalds
linus torvalds
15
27.78%
1
20.00%
stig telfer
stig telfer
11
20.37%
2
40.00%
greg kroah-hartman
greg kroah-hartman
1
1.85%
1
20.00%
Total
54
100.00%
5
100.00%



static int pcf_isa_getown(void *data)
{
	return (own);
}


Contributors
Person
Tokens
Prop
Commits
CommitProp
pre-git
pre-git
14
93.33%
1
50.00%
linus torvalds
linus torvalds
1
6.67%
1
50.00%
Total
15
100.00%
2
100.00%



static int pcf_isa_getclock(void *data)
{
	return (clock);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
pre-git
pre-git
14
93.33%
1
50.00%
linus torvalds
linus torvalds
1
6.67%
1
50.00%
Total
15
100.00%
2
100.00%



static void pcf_isa_waitforpin(void *data)
{
	DEFINE_WAIT(wait);
	int timeout = 2;
	unsigned long flags;

	if (irq > 0) {
		spin_lock_irqsave(&lock, flags);
		if (pcf_pending == 0) {
			spin_unlock_irqrestore(&lock, flags);
			prepare_to_wait(&pcf_wait, &wait, TASK_INTERRUPTIBLE);
			if (schedule_timeout(timeout*HZ)) {
				spin_lock_irqsave(&lock, flags);
				if (pcf_pending == 1) {
					pcf_pending = 0;
				}
				spin_unlock_irqrestore(&lock, flags);
			}
			finish_wait(&pcf_wait, &wait);
		} else {
			pcf_pending = 0;
			spin_unlock_irqrestore(&lock, flags);
		}
	} else {
		udelay(100);
	}
}


Contributors
Person
Tokens
Prop
Commits
CommitProp
aristeu sergio rozanski filho
aristeu sergio rozanski filho
57
41.30%
1
16.67%
pre-git
pre-git
52
37.68%
1
16.67%
domen puncer
domen puncer
25
18.12%
1
16.67%
david s. miller
david s. miller
2
1.45%
1
16.67%
frank beesley
frank beesley
1
0.72%
1
16.67%
linus torvalds
linus torvalds
1
0.72%
1
16.67%
Total
138
100.00%
6
100.00%



static irqreturn_t pcf_isa_handler(int this_irq, void *dev_id) {
	spin_lock(&lock);
	pcf_pending = 1;
	spin_unlock(&lock);
	wake_up_interruptible(&pcf_wait);
	return IRQ_HANDLED;
}


Contributors
Person
Tokens
Prop
Commits
CommitProp
pre-git
pre-git
22
57.89%
1
33.33%
aristeu sergio rozanski filho
aristeu sergio rozanski filho
12
31.58%
1
33.33%
andrew morton
andrew morton
4
10.53%
1
33.33%
Total
38
100.00%
3
100.00%



static int pcf_isa_init(void)
{
	spin_lock_init(&lock);
	if (!mmapped) {
		if (!request_region(base, 2, pcf_isa_ops.name)) {
			printk(KERN_ERR "%s: requested I/O region (%#x:2) is "
			       "in use\n", pcf_isa_ops.name, base);
			return -ENODEV;
		}
		base_iomem = ioport_map(base, 2);
		if (!base_iomem) {
			printk(KERN_ERR "%s: remap of I/O region %#x failed\n",
			       pcf_isa_ops.name, base);
			release_region(base, 2);
			return -ENODEV;
		}
	} else {
		if (!request_mem_region(base, 2, pcf_isa_ops.name)) {
			printk(KERN_ERR "%s: requested memory region (%#x:2) "
			       "is in use\n", pcf_isa_ops.name, base);
			return -ENODEV;
		}
		base_iomem = ioremap(base, 2);
		if (base_iomem == NULL) {
			printk(KERN_ERR "%s: remap of memory region %#x "
			       "failed\n", pcf_isa_ops.name, base);
			release_mem_region(base, 2);
			return -ENODEV;
		}
	}
	pr_debug("%s: registers %#x remapped to %p\n", pcf_isa_ops.name, base,
		 base_iomem);

	if (irq > 0) {
		if (request_irq(irq, pcf_isa_handler, 0, pcf_isa_ops.name,
				NULL) < 0) {
			printk(KERN_ERR "%s: Request irq%d failed\n",
			       pcf_isa_ops.name, irq);
			irq = 0;
		} else
			enable_irq(irq);
	}
	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
stig telfer
stig telfer
146
61.60%
2
22.22%
pre-git
pre-git
59
24.89%
1
11.11%
linus torvalds
linus torvalds
19
8.02%
1
11.11%
aristeu sergio rozanski filho
aristeu sergio rozanski filho
6
2.53%
1
11.11%
christoph hellwig
christoph hellwig
4
1.69%
2
22.22%
albert cranford
albert cranford
2
0.84%
1
11.11%
greg kroah-hartman
greg kroah-hartman
1
0.42%
1
11.11%
Total
237
100.00%
9
100.00%

/* ------------------------------------------------------------------------
 * Encapsulate the above functions in the correct operations structure.
 * This is only done when more than one hardware adapter is supported.
 */

static struct i2c_algo_pcf_data pcf_isa_data = {
	.setpcf	    = pcf_isa_setbyte,
	.getpcf	    = pcf_isa_getbyte,
	.getown	    = pcf_isa_getown,
	.getclock   = pcf_isa_getclock,
	.waitforpin = pcf_isa_waitforpin,
};


static struct i2c_adapter pcf_isa_ops = {
	.owner		= THIS_MODULE,
	.class		= I2C_CLASS_HWMON | I2C_CLASS_SPD,
	.algo_data	= &pcf_isa_data,
	.name		= "i2c-elektor",
};



static int elektor_match(struct device *dev, unsigned int id)
{
#ifdef __alpha__
	/* check to see we have memory mapped PCF8584 connected to the
        Cypress cy82c693 PCI-ISA bridge as on UP2000 board */
	if (base == 0) {
		struct pci_dev *cy693_dev;

		cy693_dev = pci_get_device(PCI_VENDOR_ID_CONTAQ,
					   PCI_DEVICE_ID_CONTAQ_82C693, NULL);
		if (cy693_dev) {
			unsigned char config;
			/* yeap, we've found cypress, let's check config */
			if (!pci_read_config_byte(cy693_dev, 0x47, &config)) {

				dev_dbg(dev, "found cy82c693, config "
					"register 0x47 = 0x%02x\n", config);

				/* UP2000 board has this register set to 0xe1,
                                   but the most significant bit as seems can be
                                   reset during the proper initialisation
                                   sequence if guys from API decides to do that
                                   (so, we can even enable Tsunami Pchip
                                   window for the upper 1 Gb) */

				/* so just check for ROMCS at 0xe0000,
                                   ROMCS enabled for writes
                                   and external XD Bus buffer in use. */
				if ((config & 0x7f) == 0x61) {
					/* seems to be UP2000 like board */
					base = 0xe0000;
					mmapped = 1;
					/* UP2000 drives ISA with
                                           8.25 MHz (PCI/4) clock
                                           (this can be read from cypress) */
					clock = I2C_PCF_CLK | I2C_PCF_TRNS90;
					dev_info(dev, "found API UP2000 like "
						 "board, will probe PCF8584 "
						 "later\n");
				}
			}
			pci_dev_put(cy693_dev);
		}
	}
#endif

	/* sanity checks for mmapped I/O */
	if (mmapped && base < 0xc8000) {
		dev_err(dev, "incorrect base address (%#x) specified "
		       "for mmapped I/O\n", base);
		return 0;
	}

	if (base == 0) {
		base = DEFAULT_BASE;
	}
	return 1;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
linus torvalds
linus torvalds
88
53.66%
1
14.29%
pre-git
pre-git
30
18.29%
1
14.29%
jean delvare
jean delvare
26
15.85%
1
14.29%
greg kroah-hartman
greg kroah-hartman
10
6.10%
1
14.29%
stig telfer
stig telfer
9
5.49%
2
28.57%
christoph hellwig
christoph hellwig
1
0.61%
1
14.29%
Total
164
100.00%
7
100.00%



static int elektor_probe(struct device *dev, unsigned int id)
{
	init_waitqueue_head(&pcf_wait);
	if (pcf_isa_init())
		return -ENODEV;
	pcf_isa_ops.dev.parent = dev;
	if (i2c_pcf_add_bus(&pcf_isa_ops) < 0)
		goto fail;

	dev_info(dev, "found device at %#x\n", base);

	return 0;

 fail:
	if (irq > 0) {
		disable_irq(irq);
		free_irq(irq, NULL);
	}

	if (!mmapped) {
		ioport_unmap(base_iomem);
		release_region(base, 2);
	} else {
		iounmap(base_iomem);
		release_mem_region(base, 2);
	}
	return -ENODEV;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
christoph hellwig
christoph hellwig
44
35.77%
1
14.29%
pre-git
pre-git
29
23.58%
1
14.29%
stig telfer
stig telfer
26
21.14%
2
28.57%
jean delvare
jean delvare
22
17.89%
1
14.29%
greg kroah-hartman
greg kroah-hartman
1
0.81%
1
14.29%
albert cranford
albert cranford
1
0.81%
1
14.29%
Total
123
100.00%
7
100.00%



static int elektor_remove(struct device *dev, unsigned int id)
{
	i2c_del_adapter(&pcf_isa_ops);

	if (irq > 0) {
		disable_irq(irq);
		free_irq(irq, NULL);
	}

	if (!mmapped) {
		ioport_unmap(base_iomem);
		release_region(base, 2);
	} else {
		iounmap(base_iomem);
		release_mem_region(base, 2);
	}

	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
christoph hellwig
christoph hellwig
35
44.87%
1
14.29%
stig telfer
stig telfer
21
26.92%
1
14.29%
jean delvare
jean delvare
15
19.23%
2
28.57%
pre-git
pre-git
5
6.41%
1
14.29%
greg kroah-hartman
greg kroah-hartman
1
1.28%
1
14.29%
linus torvalds
linus torvalds
1
1.28%
1
14.29%
Total
78
100.00%
7
100.00%


static struct isa_driver i2c_elektor_driver = {
	.match		= elektor_match,
	.probe		= elektor_probe,
	.remove		= elektor_remove,
	.driver = {
		.owner	= THIS_MODULE,
		.name	= "i2c-elektor",
        },
};



static int __init i2c_pcfisa_init(void)
{
	return isa_register_driver(&i2c_elektor_driver, 1);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
jean delvare
jean delvare
18
100.00%
1
100.00%
Total
18
100.00%
1
100.00%



static void __exit i2c_pcfisa_exit(void)
{
	isa_unregister_driver(&i2c_elektor_driver);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
jean delvare
jean delvare
14
93.33%
1
50.00%
stig telfer
stig telfer
1
6.67%
1
50.00%
Total
15
100.00%
2
100.00%

MODULE_AUTHOR("Hans Berglund <hb@spacetec.no>");
MODULE_DESCRIPTION("I2C-Bus adapter routines for PCF8584 ISA bus adapter");
MODULE_LICENSE("GPL");

module_param(base, int, 0);
module_param(irq, int, 0);
module_param(clock, int, 0);
module_param(own, int, 0);
module_param(mmapped, int, 0);


module_init(i2c_pcfisa_init);

module_exit(i2c_pcfisa_exit);
Overall Contributors
Person
Tokens
Prop
Commits
CommitProp
pre-git
pre-git
421
33.68%
2
6.67%
stig telfer
stig telfer
245
19.60%
2
6.67%
linus torvalds
linus torvalds
155
12.40%
2
6.67%
jean delvare
jean delvare
142
11.36%
4
13.33%
christoph hellwig
christoph hellwig
95
7.60%
3
10.00%
aristeu sergio rozanski filho
aristeu sergio rozanski filho
79
6.32%
1
3.33%
greg kroah-hartman
greg kroah-hartman
40
3.20%
6
20.00%
arnaldo carvalho de melo
arnaldo carvalho de melo
27
2.16%
1
3.33%
domen puncer
domen puncer
25
2.00%
1
3.33%
albert cranford
albert cranford
10
0.80%
1
3.33%
andrew morton
andrew morton
4
0.32%
1
3.33%
david s. miller
david s. miller
2
0.16%
1
3.33%
jan engelhardt
jan engelhardt
1
0.08%
1
3.33%
h hartley sweeten
h hartley sweeten
1
0.08%
1
3.33%
frank beesley
frank beesley
1
0.08%
1
3.33%
wolfram sang
wolfram sang
1
0.08%
1
3.33%
lucas de marchi
lucas de marchi
1
0.08%
1
3.33%
Total
1250
100.00%
30
100.00%
  
Directory: drivers/i2c/busses

Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.