[net-next-2.6.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/init.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 <asm/irq.h>
#include <asm/io.h>

#define res_len(r)		((r)->end - (r)->start + 1)

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;
	long ret = ~0;
	unsigned long timeout;

	if (i2c->irq) {
		ret = wait_event_interruptible_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;
		while (((i2c->algo_data.read_byte(i2c, I2C_PCA_CON)
				& I2C_PCA_CON_SI) == 0)
				&& (ret = time_before(jiffies, timeout)))
			udelay(100);
	}

	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_interruptible(&i2c->wait);

	return IRQ_HANDLED;
}


static int __devinit 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 =
				pdev->dev.platform_data;
	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, res_len(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, res_len(res));
	if (!i2c->reg_base) {
		ret = -ENOMEM;
		goto e_remap;
	}
	i2c->io_base = res->start;
	i2c->io_size = res_len(res);
	i2c->irq = irq;

	i2c->adap.nr = pdev->id >= 0 ? pdev->id : 0;
	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;
	i2c->adap.timeout = platform_data->timeout;

	i2c->algo_data.i2c_clock = platform_data->i2c_clock_speed;
	i2c->algo_data.data = i2c;

	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;
	}

	i2c->algo_data.wait_for_completion = i2c_pca_pf_waitforcompletion;

	i2c->gpio = platform_data->gpio;
	i2c->algo_data.reset_chip = i2c_pca_pf_dummyreset;

	/* 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, i2c->adap.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, res_len(res));
e_print:
	printk(KERN_ERR "Registering PCA9564/PCA9665 FAILED! (%d)\n", ret);
	return ret;
}

static int __devexit i2c_pca_pf_remove(struct platform_device *pdev)
{
	struct i2c_pca_pf_data *i2c = platform_get_drvdata(pdev);
	platform_set_drvdata(pdev, NULL);

	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 = __devexit_p(i2c_pca_pf_remove),
	.driver = {
		.name = "i2c-pca-platform",
		.owner = THIS_MODULE,
	},
};

static int __init i2c_pca_pf_init(void)
{
	return platform_driver_register(&i2c_pca_pf_driver);
}

static void __exit i2c_pca_pf_exit(void)
{
	platform_driver_unregister(&i2c_pca_pf_driver);
}

MODULE_AUTHOR("Wolfram Sang <w.sang@pengutronix.de>");
MODULE_DESCRIPTION("I2C-PCA9564/PCA9665 platform driver");
MODULE_LICENSE("GPL");

module_init(i2c_pca_pf_init);
module_exit(i2c_pca_pf_exit);
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>
	15	#include <linux/init.h>
	16	#include <linux/slab.h>
	17	#include <linux/delay.h>
2378bc09	18	#include <linux/jiffies.h>
244fbbb8 WS	19	#include <linux/errno.h>
	20	#include <linux/i2c.h>
	21	#include <linux/interrupt.h>
	22	#include <linux/platform_device.h>
	23	#include <linux/i2c-algo-pca.h>
	24	#include <linux/i2c-pca-platform.h>
	25	#include <linux/gpio.h>
	26
	27	#include <asm/irq.h>
	28	#include <asm/io.h>
	29
	30	#define res_len(r) ((r)->end - (r)->start + 1)
	31
	32	struct i2c_pca_pf_data {
	33	void __iomem *reg_base;
	34	int irq; /* if 0, use polling */
	35	int gpio;
	36	wait_queue_head_t wait;
	37	struct i2c_adapter adap;
	38	struct i2c_algo_pca_data algo_data;
	39	unsigned long io_base;
	40	unsigned long io_size;
	41	};
	42
	43	/* Read/Write functions for different register alignments */
	44
	45	static int i2c_pca_pf_readbyte8(void *pd, int reg)
	46	{
	47	struct i2c_pca_pf_data *i2c = pd;
	48	return ioread8(i2c->reg_base + reg);
	49	}
	50
	51	static int i2c_pca_pf_readbyte16(void *pd, int reg)
	52	{
	53	struct i2c_pca_pf_data *i2c = pd;
	54	return ioread8(i2c->reg_base + reg * 2);
	55	}
	56
	57	static int i2c_pca_pf_readbyte32(void *pd, int reg)
	58	{
	59	struct i2c_pca_pf_data *i2c = pd;
	60	return ioread8(i2c->reg_base + reg * 4);
	61	}
	62
	63	static void i2c_pca_pf_writebyte8(void *pd, int reg, int val)
	64	{
	65	struct i2c_pca_pf_data *i2c = pd;
	66	iowrite8(val, i2c->reg_base + reg);
	67	}
	68
	69	static void i2c_pca_pf_writebyte16(void *pd, int reg, int val)
	70	{
	71	struct i2c_pca_pf_data *i2c = pd;
	72	iowrite8(val, i2c->reg_base + reg * 2);
	73	}
	74
	75	static void i2c_pca_pf_writebyte32(void *pd, int reg, int val)
	76	{
	77	struct i2c_pca_pf_data *i2c = pd;
	78	iowrite8(val, i2c->reg_base + reg * 4);
	79	}
	80
	81
	82	static int i2c_pca_pf_waitforcompletion(void *pd)
83	{
84	struct i2c_pca_pf_data *i2c = pd;
2378bc09 WS	85	long ret = ~0;
2378bc09 WS	86	unsigned long timeout;
244fbbb8 WS	87
244fbbb8 WS	88	if (i2c->irq) {
2378bc09	89	ret = wait_event_interruptible_timeout(i2c->wait,
244fbbb8	90	i2c->algo_data.read_byte(i2c, I2C_PCA_CON)
2378bc09	91	& I2C_PCA_CON_SI, i2c->adap.timeout);
244fbbb8	92	} else {
2378bc09 WS	93	/* Do polling */
	94	timeout = jiffies + i2c->adap.timeout;
	95	while (((i2c->algo_data.read_byte(i2c, I2C_PCA_CON)
244fbbb8	96	& I2C_PCA_CON_SI) == 0)
2378bc09	97	&& (ret = time_before(jiffies, timeout)))
244fbbb8 WS	98	udelay(100);
	99	}
	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
	127	wake_up_interruptible(&i2c->wait);
	128
	129	return IRQ_HANDLED;
	130	}
	131
	132
	133	static int __devinit i2c_pca_pf_probe(struct platform_device *pdev)
	134	{
	135	struct i2c_pca_pf_data *i2c;
	136	struct resource *res;
	137	struct i2c_pca9564_pf_platform_data *platform_data =
	138	pdev->dev.platform_data;
	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
	151	if (!request_mem_region(res->start, res_len(res), res->name)) {
	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
	164	i2c->reg_base = ioremap(res->start, res_len(res));
	165	if (!i2c->reg_base) {
7650da02	166	ret = -ENOMEM;
244fbbb8 WS	167	goto e_remap;
	168	}
	169	i2c->io_base = res->start;
	170	i2c->io_size = res_len(res);
	171	i2c->irq = irq;
	172
	173	i2c->adap.nr = pdev->id >= 0 ? pdev->id : 0;
	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;
	179	i2c->adap.dev.parent = &pdev->dev;
	180	i2c->adap.timeout = platform_data->timeout;
	181
	182	i2c->algo_data.i2c_clock = platform_data->i2c_clock_speed;
	183	i2c->algo_data.data = i2c;
	184
	185	switch (res->flags & IORESOURCE_MEM_TYPE_MASK) {
	186	case IORESOURCE_MEM_32BIT:
	187	i2c->algo_data.write_byte = i2c_pca_pf_writebyte32;
	188	i2c->algo_data.read_byte = i2c_pca_pf_readbyte32;
	189	break;
	190	case IORESOURCE_MEM_16BIT:
	191	i2c->algo_data.write_byte = i2c_pca_pf_writebyte16;
	192	i2c->algo_data.read_byte = i2c_pca_pf_readbyte16;
	193	break;
	194	case IORESOURCE_MEM_8BIT:
	195	default:
	196	i2c->algo_data.write_byte = i2c_pca_pf_writebyte8;
	197	i2c->algo_data.read_byte = i2c_pca_pf_readbyte8;
	198	break;
	199	}
	200
	201	i2c->algo_data.wait_for_completion = i2c_pca_pf_waitforcompletion;
	202
	203	i2c->gpio = platform_data->gpio;
	204	i2c->algo_data.reset_chip = i2c_pca_pf_dummyreset;
	205
	206	/* Use gpio_is_valid() when in mainline */
	207	if (i2c->gpio > -1) {
	208	ret = gpio_request(i2c->gpio, i2c->adap.name);
	209	if (ret == 0) {
	210	gpio_direction_output(i2c->gpio, 1);
	211	i2c->algo_data.reset_chip = i2c_pca_pf_resetchip;
	212	} else {
	213	printk(KERN_WARNING "%s: Registering gpio failed!\n",
	214	i2c->adap.name);
	215	i2c->gpio = ret;
	216	}
	217	}
	218
	219	if (irq) {
	220	ret = request_irq(irq, i2c_pca_pf_handler,
	221	IRQF_TRIGGER_FALLING, i2c->adap.name, i2c);
	222	if (ret)
	223	goto e_reqirq;
	224	}
	225
	226	if (i2c_pca_add_numbered_bus(&i2c->adap) < 0) {
	227	ret = -ENODEV;
	228	goto e_adapt;
	229	}
	230
	231	platform_set_drvdata(pdev, i2c);
	232
	233	printk(KERN_INFO "%s registered.\n", i2c->adap.name);
	234
	235	return 0;
	236
	237	e_adapt:
	238	if (irq)
	239	free_irq(irq, i2c);
	240	e_reqirq:
	241	if (i2c->gpio > -1)
242	gpio_free(i2c->gpio);
243
244	iounmap(i2c->reg_base);
245	e_remap:
246	kfree(i2c);
247	e_alloc:
248	release_mem_region(res->start, res_len(res));
249	e_print:
eff9ec95	250	printk(KERN_ERR "Registering PCA9564/PCA9665 FAILED! (%d)\n", ret);
244fbbb8 WS	251	return ret;
	252	}
	253
	254	static int __devexit i2c_pca_pf_remove(struct platform_device *pdev)
	255	{
	256	struct i2c_pca_pf_data *i2c = platform_get_drvdata(pdev);
	257	platform_set_drvdata(pdev, NULL);
	258
	259	i2c_del_adapter(&i2c->adap);
	260
	261	if (i2c->irq)
	262	free_irq(i2c->irq, i2c);
	263
	264	if (i2c->gpio > -1)
	265	gpio_free(i2c->gpio);
	266
	267	iounmap(i2c->reg_base);
	268	release_mem_region(i2c->io_base, i2c->io_size);
	269	kfree(i2c);
	270
	271	return 0;
	272	}
	273
	274	static struct platform_driver i2c_pca_pf_driver = {
	275	.probe = i2c_pca_pf_probe,
	276	.remove = __devexit_p(i2c_pca_pf_remove),
	277	.driver = {
	278	.name = "i2c-pca-platform",
	279	.owner = THIS_MODULE,
	280	},
	281	};
	282
	283	static int __init i2c_pca_pf_init(void)
	284	{
	285	return platform_driver_register(&i2c_pca_pf_driver);
	286	}
	287
	288	static void __exit i2c_pca_pf_exit(void)
	289	{
	290	platform_driver_unregister(&i2c_pca_pf_driver);
	291	}
	292
	293	MODULE_AUTHOR("Wolfram Sang <w.sang@pengutronix.de>");
eff9ec95	294	MODULE_DESCRIPTION("I2C-PCA9564/PCA9665 platform driver");
244fbbb8 WS	295	MODULE_LICENSE("GPL");
	296
	297	module_init(i2c_pca_pf_init);
	298	module_exit(i2c_pca_pf_exit);
	299