[deliverable/linux.git] / drivers / i2c / busses / i2c-pca-isa.c

/*
 *  i2c-pca-isa.c driver for PCA9564 on ISA boards
 *    Copyright (C) 2004 Arcom Control Systems
 *
 *  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.
 */

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

#include <linux/i2c.h>
#include <linux/i2c-algo-pca.h>

#include <asm/io.h>
#include <asm/irq.h>

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

#define IO_SIZE 4

#undef DEBUG_IO
//#define DEBUG_IO

static unsigned long base   = 0x330;
static int irq 	  = 10;

/* Data sheet recommends 59kHz for 100kHz operation due to variation
 * in the actual clock rate */
static int clock  = I2C_PCA_CON_59kHz;

static int own    = 0x55;

static wait_queue_head_t pca_wait;

static int pca_isa_getown(struct i2c_algo_pca_data *adap)
{
	return (own);
}

static int pca_isa_getclock(struct i2c_algo_pca_data *adap)
{
	return (clock);
}

static void
pca_isa_writebyte(struct i2c_algo_pca_data *adap, int reg, int val)
{
#ifdef DEBUG_IO
	static char *names[] = { "T/O", "DAT", "ADR", "CON" };
	printk("*** write %s at %#lx <= %#04x\n", names[reg], base+reg, val);
#endif
	outb(val, base+reg);
}

static int
pca_isa_readbyte(struct i2c_algo_pca_data *adap, int reg)
{
	int res = inb(base+reg);
#ifdef DEBUG_IO
	{
		static char *names[] = { "STA", "DAT", "ADR", "CON" };	
		printk("*** read  %s => %#04x\n", names[reg], res);
	}
#endif
	return res;
}

static int pca_isa_waitforinterrupt(struct i2c_algo_pca_data *adap)
{
	int ret = 0;

	if (irq > -1) {
		ret = wait_event_interruptible(pca_wait,
					       pca_isa_readbyte(adap, I2C_PCA_CON) & I2C_PCA_CON_SI);
	} else {
		while ((pca_isa_readbyte(adap, I2C_PCA_CON) & I2C_PCA_CON_SI) == 0) 
			udelay(100);
	}
	return ret;
}

static irqreturn_t pca_handler(int this_irq, void *dev_id) {
	wake_up_interruptible(&pca_wait);
	return IRQ_HANDLED;
}

static struct i2c_algo_pca_data pca_isa_data = {
	.get_own		= pca_isa_getown,
	.get_clock		= pca_isa_getclock,
	.write_byte		= pca_isa_writebyte,
	.read_byte		= pca_isa_readbyte,
	.wait_for_interrupt	= pca_isa_waitforinterrupt,
};

static struct i2c_adapter pca_isa_ops = {
	.owner          = THIS_MODULE,
	.id		= I2C_HW_A_ISA,
	.algo_data	= &pca_isa_data,
	.name		= "PCA9564 ISA Adapter",
};

static int __init pca_isa_init(void)
{

	init_waitqueue_head(&pca_wait);

	printk(KERN_INFO "i2c-pca-isa: i/o base %#08lx. irq %d\n", base, irq);

	if (!request_region(base, IO_SIZE, "i2c-pca-isa")) {
		printk(KERN_ERR "i2c-pca-isa: I/O address %#08lx is in use.\n", base);
		goto out;
	}

	if (irq > -1) {
		if (request_irq(irq, pca_handler, 0, "i2c-pca-isa", &pca_isa_ops) < 0) {
			printk(KERN_ERR "i2c-pca-isa: Request irq%d failed\n", irq);
			goto out_region;
		}
	}

	if (i2c_pca_add_bus(&pca_isa_ops) < 0) {
		printk(KERN_ERR "i2c-pca-isa: Failed to add i2c bus\n");
		goto out_irq;
	}

	return 0;

 out_irq:
	if (irq > -1)
		free_irq(irq, &pca_isa_ops);
 out_region:
	release_region(base, IO_SIZE);
 out:
	return -ENODEV;
}

static void pca_isa_exit(void)
{
	i2c_del_adapter(&pca_isa_ops);

	if (irq > 0) {
		disable_irq(irq);
		free_irq(irq, &pca_isa_ops);
	}
	release_region(base, IO_SIZE);
}

MODULE_AUTHOR("Ian Campbell <icampbell@arcom.com>");
MODULE_DESCRIPTION("ISA base PCA9564 driver");
MODULE_LICENSE("GPL");

module_param(base, ulong, 0);
MODULE_PARM_DESC(base, "I/O base address");

module_param(irq, int, 0);
MODULE_PARM_DESC(irq, "IRQ");
module_param(clock, int, 0);
MODULE_PARM_DESC(clock, "Clock rate as described in table 1 of PCA9564 datasheet");

module_param(own, int, 0); /* the driver can't do slave mode, so there's no real point in this */

module_init(pca_isa_init);
module_exit(pca_isa_exit);
Commit	Line	Data
1da177e4 LT	1	/*
	2	* i2c-pca-isa.c driver for PCA9564 on ISA boards
	3	* Copyright (C) 2004 Arcom Control Systems
	4	*
	5	* This program is free software; you can redistribute it and/or modify
	6	* it under the terms of the GNU General Public License as published by
	7	* the Free Software Foundation; either version 2 of the License, or
	8	* (at your option) any later version.
	9	*
	10	* This program is distributed in the hope that it will be useful,
	11	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	13	* GNU General Public License for more details.
	14	*
	15	* You should have received a copy of the GNU General Public License
	16	* along with this program; if not, write to the Free Software
	17	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	18	*/
	19
1da177e4 LT	20	#include <linux/kernel.h>
	21	#include <linux/ioport.h>
	22	#include <linux/module.h>
	23	#include <linux/moduleparam.h>
	24	#include <linux/delay.h>
	25	#include <linux/slab.h>
	26	#include <linux/init.h>
	27	#include <linux/interrupt.h>
1da177e4 LT	28	#include <linux/wait.h>
	29
	30	#include <linux/i2c.h>
	31	#include <linux/i2c-algo-pca.h>
	32
	33	#include <asm/io.h>
	34	#include <asm/irq.h>
	35
	36	#include "../algos/i2c-algo-pca.h"
	37
	38	#define IO_SIZE 4
	39
	40	#undef DEBUG_IO
	41	//#define DEBUG_IO
	42
	43	static unsigned long base = 0x330;
	44	static int irq = 10;
	45
	46	/* Data sheet recommends 59kHz for 100kHz operation due to variation
	47	* in the actual clock rate */
	48	static int clock = I2C_PCA_CON_59kHz;
	49
	50	static int own = 0x55;
	51
	52	static wait_queue_head_t pca_wait;
	53
	54	static int pca_isa_getown(struct i2c_algo_pca_data *adap)
	55	{
	56	return (own);
	57	}
	58
	59	static int pca_isa_getclock(struct i2c_algo_pca_data *adap)
	60	{
	61	return (clock);
	62	}
	63
	64	static void
	65	pca_isa_writebyte(struct i2c_algo_pca_data *adap, int reg, int val)
	66	{
	67	#ifdef DEBUG_IO
	68	static char *names[] = { "T/O", "DAT", "ADR", "CON" };
	69	printk("*** write %s at %#lx <= %#04x\n", names[reg], base+reg, val);
	70	#endif
	71	outb(val, base+reg);
	72	}
	73
	74	static int
	75	pca_isa_readbyte(struct i2c_algo_pca_data *adap, int reg)
	76	{
	77	int res = inb(base+reg);
	78	#ifdef DEBUG_IO
	79	{
	80	static char *names[] = { "STA", "DAT", "ADR", "CON" };
	81	printk("*** read %s => %#04x\n", names[reg], res);
	82	}
	83	#endif
	84	return res;
	85	}
	86
	87	static int pca_isa_waitforinterrupt(struct i2c_algo_pca_data *adap)
	88	{
	89	int ret = 0;
	90
	91	if (irq > -1) {
92	ret = wait_event_interruptible(pca_wait,
93	pca_isa_readbyte(adap, I2C_PCA_CON) & I2C_PCA_CON_SI);
94	} else {
95	while ((pca_isa_readbyte(adap, I2C_PCA_CON) & I2C_PCA_CON_SI) == 0)
96	udelay(100);
97	}
98	return ret;
99	}
100
7d12e780	101	static irqreturn_t pca_handler(int this_irq, void *dev_id) {
1da177e4 LT	102	wake_up_interruptible(&pca_wait);
	103	return IRQ_HANDLED;
	104	}
	105
	106	static struct i2c_algo_pca_data pca_isa_data = {
	107	.get_own = pca_isa_getown,
	108	.get_clock = pca_isa_getclock,
	109	.write_byte = pca_isa_writebyte,
	110	.read_byte = pca_isa_readbyte,
	111	.wait_for_interrupt = pca_isa_waitforinterrupt,
	112	};
	113
	114	static struct i2c_adapter pca_isa_ops = {
	115	.owner = THIS_MODULE,
	116	.id = I2C_HW_A_ISA,
	117	.algo_data = &pca_isa_data,
	118	.name = "PCA9564 ISA Adapter",
	119	};
	120
	121	static int __init pca_isa_init(void)
	122	{
	123
	124	init_waitqueue_head(&pca_wait);
	125
	126	printk(KERN_INFO "i2c-pca-isa: i/o base %#08lx. irq %d\n", base, irq);
	127
	128	if (!request_region(base, IO_SIZE, "i2c-pca-isa")) {
	129	printk(KERN_ERR "i2c-pca-isa: I/O address %#08lx is in use.\n", base);
	130	goto out;
	131	}
	132
	133	if (irq > -1) {
	134	if (request_irq(irq, pca_handler, 0, "i2c-pca-isa", &pca_isa_ops) < 0) {
	135	printk(KERN_ERR "i2c-pca-isa: Request irq%d failed\n", irq);
	136	goto out_region;
	137	}
	138	}
	139
	140	if (i2c_pca_add_bus(&pca_isa_ops) < 0) {
	141	printk(KERN_ERR "i2c-pca-isa: Failed to add i2c bus\n");
	142	goto out_irq;
	143	}
	144
	145	return 0;
	146
	147	out_irq:
	148	if (irq > -1)
	149	free_irq(irq, &pca_isa_ops);
	150	out_region:
	151	release_region(base, IO_SIZE);
	152	out:
	153	return -ENODEV;
	154	}
	155
	156	static void pca_isa_exit(void)
	157	{
3269711b	158	i2c_del_adapter(&pca_isa_ops);
1da177e4 LT	159
	160	if (irq > 0) {
	161	disable_irq(irq);
	162	free_irq(irq, &pca_isa_ops);
	163	}
	164	release_region(base, IO_SIZE);
	165	}
	166
	167	MODULE_AUTHOR("Ian Campbell <icampbell@arcom.com>");
	168	MODULE_DESCRIPTION("ISA base PCA9564 driver");
	169	MODULE_LICENSE("GPL");
	170
	171	module_param(base, ulong, 0);
	172	MODULE_PARM_DESC(base, "I/O base address");
	173
	174	module_param(irq, int, 0);
	175	MODULE_PARM_DESC(irq, "IRQ");
	176	module_param(clock, int, 0);
	177	MODULE_PARM_DESC(clock, "Clock rate as described in table 1 of PCA9564 datasheet");
	178
	179	module_param(own, int, 0); /* the driver can't do slave mode, so there's no real point in this */
	180
	181	module_init(pca_isa_init);
	182	module_exit(pca_isa_exit);