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

/*
 *  i2c_pca_platform.c
 *
 *  Platform driver for the PCA9564 I2C controller.
 *
 *  Copyright (C) 2008 Pengutronix
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2 as
 *  published by the Free Software Foundation.

 */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/delay.h>
#include <linux/jiffies.h>
#include <linux/errno.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/i2c-algo-pca.h>
#include <linux/i2c-pca-platform.h>
#include <linux/gpio.h>
#include <linux/io.h>

#include <asm/irq.h>

struct i2c_pca_pf_data {
	void __iomem			*reg_base;
	int				irq;	/* if 0, use polling */
	int				gpio;
	wait_queue_head_t		wait;
	struct i2c_adapter		adap;
	struct i2c_algo_pca_data	algo_data;
	unsigned long			io_base;
	unsigned long			io_size;
};

/* Read/Write functions for different register alignments */

static int i2c_pca_pf_readbyte8(void *pd, int reg)
{
	struct i2c_pca_pf_data *i2c = pd;
	return ioread8(i2c->reg_base + reg);
}

static int i2c_pca_pf_readbyte16(void *pd, int reg)
{
	struct i2c_pca_pf_data *i2c = pd;
	return ioread8(i2c->reg_base + reg * 2);
}

static int i2c_pca_pf_readbyte32(void *pd, int reg)
{
	struct i2c_pca_pf_data *i2c = pd;
	return ioread8(i2c->reg_base + reg * 4);
}

static void i2c_pca_pf_writebyte8(void *pd, int reg, int val)
{
	struct i2c_pca_pf_data *i2c = pd;
	iowrite8(val, i2c->reg_base + reg);
}

static void i2c_pca_pf_writebyte16(void *pd, int reg, int val)
{
	struct i2c_pca_pf_data *i2c = pd;
	iowrite8(val, i2c->reg_base + reg * 2);
}

static void i2c_pca_pf_writebyte32(void *pd, int reg, int val)
{
	struct i2c_pca_pf_data *i2c = pd;
	iowrite8(val, i2c->reg_base + reg * 4);
}


static int i2c_pca_pf_waitforcompletion(void *pd)
{
	struct i2c_pca_pf_data *i2c = pd;
	unsigned long timeout;
	long ret;

	if (i2c->irq) {
		ret = wait_event_timeout(i2c->wait,
			i2c->algo_data.read_byte(i2c, I2C_PCA_CON)
			& I2C_PCA_CON_SI, i2c->adap.timeout);
	} else {
		/* Do polling */
		timeout = jiffies + i2c->adap.timeout;
		do {
			ret = time_before(jiffies, timeout);
			if (i2c->algo_data.read_byte(i2c, I2C_PCA_CON)
					& I2C_PCA_CON_SI)
				break;
			udelay(100);
		} while (ret);
	}

	return ret > 0;
}

static void i2c_pca_pf_dummyreset(void *pd)
{
	struct i2c_pca_pf_data *i2c = pd;
	printk(KERN_WARNING "%s: No reset-pin found. Chip may get stuck!\n",
		i2c->adap.name);
}

static void i2c_pca_pf_resetchip(void *pd)
{
	struct i2c_pca_pf_data *i2c = pd;

	gpio_set_value(i2c->gpio, 0);
	ndelay(100);
	gpio_set_value(i2c->gpio, 1);
}

static irqreturn_t i2c_pca_pf_handler(int this_irq, void *dev_id)
{
	struct i2c_pca_pf_data *i2c = dev_id;

	if ((i2c->algo_data.read_byte(i2c, I2C_PCA_CON) & I2C_PCA_CON_SI) == 0)
		return IRQ_NONE;

	wake_up(&i2c->wait);

	return IRQ_HANDLED;
}


static int i2c_pca_pf_probe(struct platform_device *pdev)
{
	struct i2c_pca_pf_data *i2c;
	struct resource *res;
	struct i2c_pca9564_pf_platform_data *platform_data =
				dev_get_platdata(&pdev->dev);
	int ret = 0;
	int irq;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	irq = platform_get_irq(pdev, 0);
	/* If irq is 0, we do polling. */

	if (res == NULL) {
		ret = -ENODEV;
		goto e_print;
	}

	if (!request_mem_region(res->start, resource_size(res), res->name)) {
		ret = -ENOMEM;
		goto e_print;
	}

	i2c = kzalloc(sizeof(struct i2c_pca_pf_data), GFP_KERNEL);
	if (!i2c) {
		ret = -ENOMEM;
		goto e_alloc;
	}

	init_waitqueue_head(&i2c->wait);

	i2c->reg_base = ioremap(res->start, resource_size(res));
	if (!i2c->reg_base) {
		ret = -ENOMEM;
		goto e_remap;
	}
	i2c->io_base = res->start;
	i2c->io_size = resource_size(res);
	i2c->irq = irq;

	i2c->adap.nr = pdev->id;
	i2c->adap.owner = THIS_MODULE;
	snprintf(i2c->adap.name, sizeof(i2c->adap.name),
		 "PCA9564/PCA9665 at 0x%08lx",
		 (unsigned long) res->start);
	i2c->adap.algo_data = &i2c->algo_data;
	i2c->adap.dev.parent = &pdev->dev;

	if (platform_data) {
		i2c->adap.timeout = platform_data->timeout;
		i2c->algo_data.i2c_clock = platform_data->i2c_clock_speed;
		i2c->gpio = platform_data->gpio;
	} else {
		i2c->adap.timeout = HZ;
		i2c->algo_data.i2c_clock = 59000;
		i2c->gpio = -1;
	}

	i2c->algo_data.data = i2c;
	i2c->algo_data.wait_for_completion = i2c_pca_pf_waitforcompletion;
	i2c->algo_data.reset_chip = i2c_pca_pf_dummyreset;

	switch (res->flags & IORESOURCE_MEM_TYPE_MASK) {
	case IORESOURCE_MEM_32BIT:
		i2c->algo_data.write_byte = i2c_pca_pf_writebyte32;
		i2c->algo_data.read_byte = i2c_pca_pf_readbyte32;
		break;
	case IORESOURCE_MEM_16BIT:
		i2c->algo_data.write_byte = i2c_pca_pf_writebyte16;
		i2c->algo_data.read_byte = i2c_pca_pf_readbyte16;
		break;
	case IORESOURCE_MEM_8BIT:
	default:
		i2c->algo_data.write_byte = i2c_pca_pf_writebyte8;
		i2c->algo_data.read_byte = i2c_pca_pf_readbyte8;
		break;
	}

	/* Use gpio_is_valid() when in mainline */
	if (i2c->gpio > -1) {
		ret = gpio_request(i2c->gpio, i2c->adap.name);
		if (ret == 0) {
			gpio_direction_output(i2c->gpio, 1);
			i2c->algo_data.reset_chip = i2c_pca_pf_resetchip;
		} else {
			printk(KERN_WARNING "%s: Registering gpio failed!\n",
				i2c->adap.name);
			i2c->gpio = ret;
		}
	}

	if (irq) {
		ret = request_irq(irq, i2c_pca_pf_handler,
			IRQF_TRIGGER_FALLING, pdev->name, i2c);
		if (ret)
			goto e_reqirq;
	}

	if (i2c_pca_add_numbered_bus(&i2c->adap) < 0) {
		ret = -ENODEV;
		goto e_adapt;
	}

	platform_set_drvdata(pdev, i2c);

	printk(KERN_INFO "%s registered.\n", i2c->adap.name);

	return 0;

e_adapt:
	if (irq)
		free_irq(irq, i2c);
e_reqirq:
	if (i2c->gpio > -1)
		gpio_free(i2c->gpio);

	iounmap(i2c->reg_base);
e_remap:
	kfree(i2c);
e_alloc:
	release_mem_region(res->start, resource_size(res));
e_print:
	printk(KERN_ERR "Registering PCA9564/PCA9665 FAILED! (%d)\n", ret);
	return ret;
}

static int i2c_pca_pf_remove(struct platform_device *pdev)
{
	struct i2c_pca_pf_data *i2c = platform_get_drvdata(pdev);

	i2c_del_adapter(&i2c->adap);

	if (i2c->irq)
		free_irq(i2c->irq, i2c);

	if (i2c->gpio > -1)
		gpio_free(i2c->gpio);

	iounmap(i2c->reg_base);
	release_mem_region(i2c->io_base, i2c->io_size);
	kfree(i2c);

	return 0;
}

static struct platform_driver i2c_pca_pf_driver = {
	.probe = i2c_pca_pf_probe,
	.remove = i2c_pca_pf_remove,
	.driver = {
		.name = "i2c-pca-platform",
	},
};

module_platform_driver(i2c_pca_pf_driver);

MODULE_AUTHOR("Wolfram Sang <w.sang@pengutronix.de>");
MODULE_DESCRIPTION("I2C-PCA9564/PCA9665 platform driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
244fbbb8 WS	1	/*
	2	* i2c_pca_platform.c
	3	*
	4	* Platform driver for the PCA9564 I2C controller.
	5	*
	6	* Copyright (C) 2008 Pengutronix
	7	*
	8	* This program is free software; you can redistribute it and/or modify
	9	* it under the terms of the GNU General Public License version 2 as
	10	* published by the Free Software Foundation.
	11
	12	*/
	13	#include <linux/kernel.h>
	14	#include <linux/module.h>
244fbbb8 WS	15	#include <linux/slab.h>
244fbbb8 WS	16	#include <linux/delay.h>
2378bc09	17	#include <linux/jiffies.h>
244fbbb8 WS	18	#include <linux/errno.h>
	19	#include <linux/i2c.h>
	20	#include <linux/interrupt.h>
	21	#include <linux/platform_device.h>
	22	#include <linux/i2c-algo-pca.h>
	23	#include <linux/i2c-pca-platform.h>
	24	#include <linux/gpio.h>
21782180	25	#include <linux/io.h>
244fbbb8 WS	26
244fbbb8 WS	27	#include <asm/irq.h>
244fbbb8	28
244fbbb8 WS	29	struct i2c_pca_pf_data {
	30	void __iomem *reg_base;
	31	int irq; /* if 0, use polling */
	32	int gpio;
	33	wait_queue_head_t wait;
	34	struct i2c_adapter adap;
	35	struct i2c_algo_pca_data algo_data;
	36	unsigned long io_base;
	37	unsigned long io_size;
	38	};
	39
	40	/* Read/Write functions for different register alignments */
	41
	42	static int i2c_pca_pf_readbyte8(void *pd, int reg)
	43	{
	44	struct i2c_pca_pf_data *i2c = pd;
	45	return ioread8(i2c->reg_base + reg);
	46	}
	47
	48	static int i2c_pca_pf_readbyte16(void *pd, int reg)
	49	{
	50	struct i2c_pca_pf_data *i2c = pd;
	51	return ioread8(i2c->reg_base + reg * 2);
	52	}
	53
	54	static int i2c_pca_pf_readbyte32(void *pd, int reg)
	55	{
	56	struct i2c_pca_pf_data *i2c = pd;
	57	return ioread8(i2c->reg_base + reg * 4);
	58	}
	59
	60	static void i2c_pca_pf_writebyte8(void *pd, int reg, int val)
	61	{
	62	struct i2c_pca_pf_data *i2c = pd;
	63	iowrite8(val, i2c->reg_base + reg);
	64	}
	65
	66	static void i2c_pca_pf_writebyte16(void *pd, int reg, int val)
	67	{
	68	struct i2c_pca_pf_data *i2c = pd;
	69	iowrite8(val, i2c->reg_base + reg * 2);
	70	}
	71
	72	static void i2c_pca_pf_writebyte32(void *pd, int reg, int val)
	73	{
	74	struct i2c_pca_pf_data *i2c = pd;
	75	iowrite8(val, i2c->reg_base + reg * 4);
	76	}
	77
	78
	79	static int i2c_pca_pf_waitforcompletion(void *pd)
	80	{
	81	struct i2c_pca_pf_data *i2c = pd;
2378bc09	82	unsigned long timeout;
6abb930a	83	long ret;
244fbbb8 WS	84
244fbbb8 WS	85	if (i2c->irq) {
22f8b269	86	ret = wait_event_timeout(i2c->wait,
244fbbb8	87	i2c->algo_data.read_byte(i2c, I2C_PCA_CON)
2378bc09	88	& I2C_PCA_CON_SI, i2c->adap.timeout);
244fbbb8	89	} else {
2378bc09 WS	90	/* Do polling */
2378bc09 WS	91	timeout = jiffies + i2c->adap.timeout;
6abb930a YY	92	do {
	93	ret = time_before(jiffies, timeout);
	94	if (i2c->algo_data.read_byte(i2c, I2C_PCA_CON)
	95	& I2C_PCA_CON_SI)
	96	break;
244fbbb8	97	udelay(100);
6abb930a	98	} while (ret);
244fbbb8 WS	99	}
244fbbb8 WS	100
2378bc09	101	return ret > 0;
244fbbb8 WS	102	}
	103
	104	static void i2c_pca_pf_dummyreset(void *pd)
	105	{
	106	struct i2c_pca_pf_data *i2c = pd;
	107	printk(KERN_WARNING "%s: No reset-pin found. Chip may get stuck!\n",
	108	i2c->adap.name);
	109	}
	110
	111	static void i2c_pca_pf_resetchip(void *pd)
	112	{
	113	struct i2c_pca_pf_data *i2c = pd;
	114
	115	gpio_set_value(i2c->gpio, 0);
	116	ndelay(100);
	117	gpio_set_value(i2c->gpio, 1);
	118	}
	119
	120	static irqreturn_t i2c_pca_pf_handler(int this_irq, void *dev_id)
	121	{
	122	struct i2c_pca_pf_data *i2c = dev_id;
	123
	124	if ((i2c->algo_data.read_byte(i2c, I2C_PCA_CON) & I2C_PCA_CON_SI) == 0)
	125	return IRQ_NONE;
	126
22f8b269	127	wake_up(&i2c->wait);
244fbbb8 WS	128
	129	return IRQ_HANDLED;
	130	}
	131
	132
0b255e92	133	static int i2c_pca_pf_probe(struct platform_device *pdev)
244fbbb8 WS	134	{
	135	struct i2c_pca_pf_data *i2c;
	136	struct resource *res;
	137	struct i2c_pca9564_pf_platform_data *platform_data =
6d4028c6	138	dev_get_platdata(&pdev->dev);
244fbbb8 WS	139	int ret = 0;
	140	int irq;
	141
	142	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	143	irq = platform_get_irq(pdev, 0);
	144	/* If irq is 0, we do polling. */
	145
	146	if (res == NULL) {
	147	ret = -ENODEV;
	148	goto e_print;
	149	}
	150
c6ffddea	151	if (!request_mem_region(res->start, resource_size(res), res->name)) {
244fbbb8 WS	152	ret = -ENOMEM;
	153	goto e_print;
	154	}
	155
	156	i2c = kzalloc(sizeof(struct i2c_pca_pf_data), GFP_KERNEL);
	157	if (!i2c) {
	158	ret = -ENOMEM;
	159	goto e_alloc;
	160	}
	161
	162	init_waitqueue_head(&i2c->wait);
	163
c6ffddea	164	i2c->reg_base = ioremap(res->start, resource_size(res));
244fbbb8	165	if (!i2c->reg_base) {
7650da02	166	ret = -ENOMEM;
244fbbb8 WS	167	goto e_remap;
	168	}
	169	i2c->io_base = res->start;
c6ffddea	170	i2c->io_size = resource_size(res);
244fbbb8 WS	171	i2c->irq = irq;
244fbbb8 WS	172
44454baa	173	i2c->adap.nr = pdev->id;
244fbbb8	174	i2c->adap.owner = THIS_MODULE;
eff9ec95 MAC	175	snprintf(i2c->adap.name, sizeof(i2c->adap.name),
	176	"PCA9564/PCA9665 at 0x%08lx",
	177	(unsigned long) res->start);
244fbbb8 WS	178	i2c->adap.algo_data = &i2c->algo_data;
244fbbb8 WS	179	i2c->adap.dev.parent = &pdev->dev;
244fbbb8	180
6b110d13 WS	181	if (platform_data) {
	182	i2c->adap.timeout = platform_data->timeout;
	183	i2c->algo_data.i2c_clock = platform_data->i2c_clock_speed;
	184	i2c->gpio = platform_data->gpio;
	185	} else {
	186	i2c->adap.timeout = HZ;
	187	i2c->algo_data.i2c_clock = 59000;
	188	i2c->gpio = -1;
	189	}
	190
244fbbb8	191	i2c->algo_data.data = i2c;
6b110d13 WS	192	i2c->algo_data.wait_for_completion = i2c_pca_pf_waitforcompletion;
6b110d13 WS	193	i2c->algo_data.reset_chip = i2c_pca_pf_dummyreset;
244fbbb8 WS	194
	195	switch (res->flags & IORESOURCE_MEM_TYPE_MASK) {
	196	case IORESOURCE_MEM_32BIT:
	197	i2c->algo_data.write_byte = i2c_pca_pf_writebyte32;
	198	i2c->algo_data.read_byte = i2c_pca_pf_readbyte32;
	199	break;
	200	case IORESOURCE_MEM_16BIT:
	201	i2c->algo_data.write_byte = i2c_pca_pf_writebyte16;
	202	i2c->algo_data.read_byte = i2c_pca_pf_readbyte16;
	203	break;
	204	case IORESOURCE_MEM_8BIT:
	205	default:
	206	i2c->algo_data.write_byte = i2c_pca_pf_writebyte8;
	207	i2c->algo_data.read_byte = i2c_pca_pf_readbyte8;
	208	break;
	209	}
	210
244fbbb8 WS	211	/* Use gpio_is_valid() when in mainline */
	212	if (i2c->gpio > -1) {
	213	ret = gpio_request(i2c->gpio, i2c->adap.name);
	214	if (ret == 0) {
	215	gpio_direction_output(i2c->gpio, 1);
	216	i2c->algo_data.reset_chip = i2c_pca_pf_resetchip;
	217	} else {
	218	printk(KERN_WARNING "%s: Registering gpio failed!\n",
	219	i2c->adap.name);
	220	i2c->gpio = ret;
	221	}
	222	}
	223
	224	if (irq) {
	225	ret = request_irq(irq, i2c_pca_pf_handler,
32358443	226	IRQF_TRIGGER_FALLING, pdev->name, i2c);
244fbbb8 WS	227	if (ret)
	228	goto e_reqirq;
	229	}
	230
	231	if (i2c_pca_add_numbered_bus(&i2c->adap) < 0) {
	232	ret = -ENODEV;
	233	goto e_adapt;
	234	}
	235
	236	platform_set_drvdata(pdev, i2c);
	237
	238	printk(KERN_INFO "%s registered.\n", i2c->adap.name);
	239
	240	return 0;
	241
	242	e_adapt:
	243	if (irq)
	244	free_irq(irq, i2c);
	245	e_reqirq:
	246	if (i2c->gpio > -1)
	247	gpio_free(i2c->gpio);
	248
	249	iounmap(i2c->reg_base);
	250	e_remap:
	251	kfree(i2c);
	252	e_alloc:
c6ffddea	253	release_mem_region(res->start, resource_size(res));
244fbbb8	254	e_print:
eff9ec95	255	printk(KERN_ERR "Registering PCA9564/PCA9665 FAILED! (%d)\n", ret);
244fbbb8 WS	256	return ret;
	257	}
	258
0b255e92	259	static int i2c_pca_pf_remove(struct platform_device *pdev)
244fbbb8 WS	260	{
244fbbb8 WS	261	struct i2c_pca_pf_data *i2c = platform_get_drvdata(pdev);
244fbbb8 WS	262
	263	i2c_del_adapter(&i2c->adap);
	264
	265	if (i2c->irq)
	266	free_irq(i2c->irq, i2c);
	267
	268	if (i2c->gpio > -1)
	269	gpio_free(i2c->gpio);
	270
	271	iounmap(i2c->reg_base);
	272	release_mem_region(i2c->io_base, i2c->io_size);
	273	kfree(i2c);
	274
	275	return 0;
	276	}
	277
	278	static struct platform_driver i2c_pca_pf_driver = {
	279	.probe = i2c_pca_pf_probe,
0b255e92	280	.remove = i2c_pca_pf_remove,
244fbbb8 WS	281	.driver = {
244fbbb8 WS	282	.name = "i2c-pca-platform",
244fbbb8 WS	283	},
	284	};
	285
a3664b51	286	module_platform_driver(i2c_pca_pf_driver);
244fbbb8 WS	287
244fbbb8 WS	288	MODULE_AUTHOR("Wolfram Sang <w.sang@pengutronix.de>");
eff9ec95	289	MODULE_DESCRIPTION("I2C-PCA9564/PCA9665 platform driver");
244fbbb8	290	MODULE_LICENSE("GPL");