[linux-2.6-block.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/platform_data/i2c-pca-platform.h>
#include <linux/gpio.h>
#include <linux/gpio/consumer.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_device.h>

#include <asm/irq.h>

struct i2c_pca_pf_data {
	void __iomem			*reg_base;
	int				irq;	/* if 0, use polling */
	struct gpio_desc		*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;

	dev_warn(&i2c->adap.dev, "No reset-pin found. Chip may get stuck!\n");
}

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

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

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);
	struct device_node *np = pdev->dev.of_node;
	int ret = 0;
	int irq;

	irq = platform_get_irq(pdev, 0);
	/* If irq is 0, we do polling. */
	if (irq < 0)
		irq = 0;

	i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL);
	if (!i2c)
		return -ENOMEM;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	i2c->reg_base = devm_ioremap_resource(&pdev->dev, res);
	if (IS_ERR(i2c->reg_base))
		return PTR_ERR(i2c->reg_base);


	init_waitqueue_head(&i2c->wait);

	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;
	i2c->adap.dev.of_node = np;

	i2c->gpio = devm_gpiod_get_optional(&pdev->dev, "reset-gpios", GPIOD_OUT_LOW);
	if (IS_ERR(i2c->gpio))
		return PTR_ERR(i2c->gpio);

	i2c->adap.timeout = HZ;
	ret = device_property_read_u32(&pdev->dev, "clock-frequency",
				       &i2c->algo_data.i2c_clock);
	if (ret)
		i2c->algo_data.i2c_clock = 59000;

	if (platform_data) {
		i2c->adap.timeout = platform_data->timeout;
		i2c->algo_data.i2c_clock = platform_data->i2c_clock_speed;
	}

	i2c->algo_data.data = i2c;
	i2c->algo_data.wait_for_completion = i2c_pca_pf_waitforcompletion;
	if (i2c->gpio)
		i2c->algo_data.reset_chip = i2c_pca_pf_resetchip;
	else
		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;
	}

	if (irq) {
		ret = devm_request_irq(&pdev->dev, irq, i2c_pca_pf_handler,
			IRQF_TRIGGER_FALLING, pdev->name, i2c);
		if (ret)
			return ret;
	}

	ret = i2c_pca_add_numbered_bus(&i2c->adap);
	if (ret)
		return ret;

	platform_set_drvdata(pdev, i2c);

	dev_info(&pdev->dev, "registered.\n");

	return 0;
}

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);

	return 0;
}

#ifdef CONFIG_OF
static const struct of_device_id i2c_pca_of_match_table[] = {
	{ .compatible = "nxp,pca9564" },
	{ .compatible = "nxp,pca9665" },
	{},
};
MODULE_DEVICE_TABLE(of, i2c_pca_of_match_table);
#endif

static struct platform_driver i2c_pca_pf_driver = {
	.probe = i2c_pca_pf_probe,
	.remove = i2c_pca_pf_remove,
	.driver = {
		.name = "i2c-pca-platform",
		.of_match_table = of_match_ptr(i2c_pca_of_match_table),
	},
};

module_platform_driver(i2c_pca_pf_driver);

MODULE_AUTHOR("Wolfram Sang <kernel@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>
e5c71377	23	#include <linux/platform_data/i2c-pca-platform.h>
244fbbb8	24	#include <linux/gpio.h>
4cc7229d	25	#include <linux/gpio/consumer.h>
21782180	26	#include <linux/io.h>
0e8ce93b CP	27	#include <linux/of.h>
0e8ce93b CP	28	#include <linux/of_device.h>
244fbbb8 WS	29
244fbbb8 WS	30	#include <asm/irq.h>
244fbbb8	31
244fbbb8 WS	32	struct i2c_pca_pf_data {
	33	void __iomem *reg_base;
	34	int irq; /* if 0, use polling */
4cc7229d	35	struct gpio_desc *gpio;
244fbbb8 WS	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	85	unsigned long timeout;
6abb930a	86	long ret;
244fbbb8 WS	87
244fbbb8 WS	88	if (i2c->irq) {
22f8b269	89	ret = wait_event_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 */
2378bc09 WS	94	timeout = jiffies + i2c->adap.timeout;
6abb930a YY	95	do {
	96	ret = time_before(jiffies, timeout);
	97	if (i2c->algo_data.read_byte(i2c, I2C_PCA_CON)
	98	& I2C_PCA_CON_SI)
	99	break;
244fbbb8	100	udelay(100);
6abb930a	101	} while (ret);
244fbbb8 WS	102	}
244fbbb8 WS	103
2378bc09	104	return ret > 0;
244fbbb8 WS	105	}
	106
	107	static void i2c_pca_pf_dummyreset(void *pd)
	108	{
	109	struct i2c_pca_pf_data *i2c = pd;
df40f247 CP	110
df40f247 CP	111	dev_warn(&i2c->adap.dev, "No reset-pin found. Chip may get stuck!\n");
244fbbb8 WS	112	}
	113
	114	static void i2c_pca_pf_resetchip(void *pd)
	115	{
	116	struct i2c_pca_pf_data *i2c = pd;
	117
4cc7229d	118	gpiod_set_value(i2c->gpio, 1);
244fbbb8	119	ndelay(100);
4cc7229d	120	gpiod_set_value(i2c->gpio, 0);
244fbbb8 WS	121	}
	122
	123	static irqreturn_t i2c_pca_pf_handler(int this_irq, void *dev_id)
	124	{
	125	struct i2c_pca_pf_data *i2c = dev_id;
	126
	127	if ((i2c->algo_data.read_byte(i2c, I2C_PCA_CON) & I2C_PCA_CON_SI) == 0)
	128	return IRQ_NONE;
	129
22f8b269	130	wake_up(&i2c->wait);
244fbbb8 WS	131
	132	return IRQ_HANDLED;
	133	}
	134
	135
0b255e92	136	static int i2c_pca_pf_probe(struct platform_device *pdev)
244fbbb8 WS	137	{
	138	struct i2c_pca_pf_data *i2c;
	139	struct resource *res;
	140	struct i2c_pca9564_pf_platform_data *platform_data =
6d4028c6	141	dev_get_platdata(&pdev->dev);
0e8ce93b	142	struct device_node *np = pdev->dev.of_node;
244fbbb8 WS	143	int ret = 0;
	144	int irq;
	145
244fbbb8 WS	146	irq = platform_get_irq(pdev, 0);
244fbbb8 WS	147	/* If irq is 0, we do polling. */
0e8ce93b CP	148	if (irq < 0)
0e8ce93b CP	149	irq = 0;
244fbbb8	150
fa70ca7c CP	151	i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL);
	152	if (!i2c)
	153	return -ENOMEM;
244fbbb8	154
fa70ca7c CP	155	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	156	i2c->reg_base = devm_ioremap_resource(&pdev->dev, res);
	157	if (IS_ERR(i2c->reg_base))
	158	return PTR_ERR(i2c->reg_base);
244fbbb8	159
244fbbb8 WS	160
	161	init_waitqueue_head(&i2c->wait);
	162
244fbbb8	163	i2c->io_base = res->start;
c6ffddea	164	i2c->io_size = resource_size(res);
244fbbb8 WS	165	i2c->irq = irq;
244fbbb8 WS	166
44454baa	167	i2c->adap.nr = pdev->id;
244fbbb8	168	i2c->adap.owner = THIS_MODULE;
eff9ec95 MAC	169	snprintf(i2c->adap.name, sizeof(i2c->adap.name),
	170	"PCA9564/PCA9665 at 0x%08lx",
	171	(unsigned long) res->start);
244fbbb8 WS	172	i2c->adap.algo_data = &i2c->algo_data;
244fbbb8 WS	173	i2c->adap.dev.parent = &pdev->dev;
0e8ce93b	174	i2c->adap.dev.of_node = np;
244fbbb8	175
06783261 CP	176	i2c->gpio = devm_gpiod_get_optional(&pdev->dev, "reset-gpios", GPIOD_OUT_LOW);
	177	if (IS_ERR(i2c->gpio))
	178	return PTR_ERR(i2c->gpio);
	179
7562dee2 CP	180	i2c->adap.timeout = HZ;
	181	ret = device_property_read_u32(&pdev->dev, "clock-frequency",
	182	&i2c->algo_data.i2c_clock);
	183	if (ret)
	184	i2c->algo_data.i2c_clock = 59000;
	185
6b110d13 WS	186	if (platform_data) {
	187	i2c->adap.timeout = platform_data->timeout;
	188	i2c->algo_data.i2c_clock = platform_data->i2c_clock_speed;
6b110d13 WS	189	}
6b110d13 WS	190
244fbbb8	191	i2c->algo_data.data = i2c;
6b110d13	192	i2c->algo_data.wait_for_completion = i2c_pca_pf_waitforcompletion;
2ec4d883 CP	193	if (i2c->gpio)
	194	i2c->algo_data.reset_chip = i2c_pca_pf_resetchip;
	195	else
	196	i2c->algo_data.reset_chip = i2c_pca_pf_dummyreset;
244fbbb8 WS	197
	198	switch (res->flags & IORESOURCE_MEM_TYPE_MASK) {
	199	case IORESOURCE_MEM_32BIT:
	200	i2c->algo_data.write_byte = i2c_pca_pf_writebyte32;
	201	i2c->algo_data.read_byte = i2c_pca_pf_readbyte32;
	202	break;
	203	case IORESOURCE_MEM_16BIT:
	204	i2c->algo_data.write_byte = i2c_pca_pf_writebyte16;
	205	i2c->algo_data.read_byte = i2c_pca_pf_readbyte16;
	206	break;
	207	case IORESOURCE_MEM_8BIT:
	208	default:
	209	i2c->algo_data.write_byte = i2c_pca_pf_writebyte8;
	210	i2c->algo_data.read_byte = i2c_pca_pf_readbyte8;
	211	break;
	212	}
	213
244fbbb8	214	if (irq) {
fa70ca7c	215	ret = devm_request_irq(&pdev->dev, irq, i2c_pca_pf_handler,
32358443	216	IRQF_TRIGGER_FALLING, pdev->name, i2c);
244fbbb8	217	if (ret)
fa70ca7c	218	return ret;
244fbbb8 WS	219	}
244fbbb8 WS	220
78e6c5ab CP	221	ret = i2c_pca_add_numbered_bus(&i2c->adap);
	222	if (ret)
	223	return ret;
244fbbb8 WS	224
	225	platform_set_drvdata(pdev, i2c);
	226
df40f247	227	dev_info(&pdev->dev, "registered.\n");
244fbbb8 WS	228
244fbbb8 WS	229	return 0;
244fbbb8 WS	230	}
244fbbb8 WS	231
0b255e92	232	static int i2c_pca_pf_remove(struct platform_device *pdev)
244fbbb8 WS	233	{
244fbbb8 WS	234	struct i2c_pca_pf_data *i2c = platform_get_drvdata(pdev);
244fbbb8 WS	235
	236	i2c_del_adapter(&i2c->adap);
	237
244fbbb8 WS	238	return 0;
	239	}
	240
0e8ce93b CP	241	#ifdef CONFIG_OF
	242	static const struct of_device_id i2c_pca_of_match_table[] = {
	243	{ .compatible = "nxp,pca9564" },
	244	{ .compatible = "nxp,pca9665" },
	245	{},
	246	};
	247	MODULE_DEVICE_TABLE(of, i2c_pca_of_match_table);
	248	#endif
	249
244fbbb8 WS	250	static struct platform_driver i2c_pca_pf_driver = {
244fbbb8 WS	251	.probe = i2c_pca_pf_probe,
0b255e92	252	.remove = i2c_pca_pf_remove,
244fbbb8 WS	253	.driver = {
244fbbb8 WS	254	.name = "i2c-pca-platform",
0e8ce93b	255	.of_match_table = of_match_ptr(i2c_pca_of_match_table),
244fbbb8 WS	256	},
	257	};
	258
a3664b51	259	module_platform_driver(i2c_pca_pf_driver);
244fbbb8	260
9ef8a0be	261	MODULE_AUTHOR("Wolfram Sang <kernel@pengutronix.de>");
eff9ec95	262	MODULE_DESCRIPTION("I2C-PCA9564/PCA9665 platform driver");
244fbbb8	263	MODULE_LICENSE("GPL");