[GitHub/mt8127/android_kernel_alcatel_ttab.git] / drivers / i2c / busses / i2c-puv3.c

/*
 * I2C driver for PKUnity-v3 SoC
 * Code specific to PKUnity SoC and UniCore ISA
 *
 *	Maintained by GUAN Xue-tao <gxt@mprc.pku.edu.cn>
 *	Copyright (C) 2001-2010 Guan Xuetao
 *
 * 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/module.h>
#include <linux/kernel.h>
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/clk.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <mach/hardware.h>

/*
 * Poll the i2c status register until the specified bit is set.
 * Returns 0 if timed out (100 msec).
 */
static short poll_status(unsigned long bit)
{
	int loop_cntr = 1000;

	if (bit & I2C_STATUS_TFNF) {
		do {
			udelay(10);
		} while (!(readl(I2C_STATUS) & bit) && (--loop_cntr > 0));
	} else {
		/* RXRDY handler */
		do {
			if (readl(I2C_TAR) == I2C_TAR_EEPROM)
				msleep(20);
			else
				udelay(10);
		} while (!(readl(I2C_RXFLR) & 0xf) && (--loop_cntr > 0));
	}

	return (loop_cntr > 0);
}

static int xfer_read(struct i2c_adapter *adap, unsigned char *buf, int length)
{
	int i2c_reg = *buf;

	/* Read data */
	while (length--) {
		if (!poll_status(I2C_STATUS_TFNF)) {
			dev_dbg(&adap->dev, "Tx FIFO Not Full timeout\n");
			return -ETIMEDOUT;
		}

		/* send addr */
		writel(i2c_reg | I2C_DATACMD_WRITE, I2C_DATACMD);

		/* get ready to next write */
		i2c_reg++;

		/* send read CMD */
		writel(I2C_DATACMD_READ, I2C_DATACMD);

		/* wait until the Rx FIFO have available */
		if (!poll_status(I2C_STATUS_RFNE)) {
			dev_dbg(&adap->dev, "RXRDY timeout\n");
			return -ETIMEDOUT;
		}

		/* read the data to buf */
		*buf = (readl(I2C_DATACMD) & I2C_DATACMD_DAT_MASK);
		buf++;
	}

	return 0;
}

static int xfer_write(struct i2c_adapter *adap, unsigned char *buf, int length)
{
	int i2c_reg = *buf;

	/* Do nothing but storing the reg_num to a static variable */
	if (i2c_reg == -1) {
		printk(KERN_WARNING "Error i2c reg\n");
		return -ETIMEDOUT;
	}

	if (length == 1)
		return 0;

	buf++;
	length--;
	while (length--) {
		/* send addr */
		writel(i2c_reg | I2C_DATACMD_WRITE, I2C_DATACMD);

		/* send write CMD */
		writel(*buf | I2C_DATACMD_WRITE, I2C_DATACMD);

		/* wait until the Rx FIFO have available */
		msleep(20);

		/* read the data to buf */
		i2c_reg++;
		buf++;
	}

	return 0;
}

/*
 * Generic i2c master transfer entrypoint.
 *
 */
static int puv3_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *pmsg,
		int num)
{
	int i, ret;
	unsigned char swap;

	/* Disable i2c */
	writel(I2C_ENABLE_DISABLE, I2C_ENABLE);

	/* Set the work mode and speed*/
	writel(I2C_CON_MASTER | I2C_CON_SPEED_STD | I2C_CON_SLAVEDISABLE, I2C_CON);

	writel(pmsg->addr, I2C_TAR);

	/* Enable i2c */
	writel(I2C_ENABLE_ENABLE, I2C_ENABLE);

	dev_dbg(&adap->dev, "puv3_i2c_xfer: processing %d messages:\n", num);

	for (i = 0; i < num; i++) {
		dev_dbg(&adap->dev, " #%d: %sing %d byte%s %s 0x%02x\n", i,
			pmsg->flags & I2C_M_RD ? "read" : "writ",
			pmsg->len, pmsg->len > 1 ? "s" : "",
			pmsg->flags & I2C_M_RD ? "from" : "to",	pmsg->addr);

		if (pmsg->len && pmsg->buf) {	/* sanity check */
			if (pmsg->flags & I2C_M_RD)
				ret = xfer_read(adap, pmsg->buf, pmsg->len);
			else
				ret = xfer_write(adap, pmsg->buf, pmsg->len);

			if (ret)
				return ret;

		}
		dev_dbg(&adap->dev, "transfer complete\n");
		pmsg++;		/* next message */
	}

	/* XXX: fixup be16_to_cpu in bq27x00_battery.c */
	if (pmsg->addr == I2C_TAR_PWIC) {
		swap = pmsg->buf[0];
		pmsg->buf[0] = pmsg->buf[1];
		pmsg->buf[1] = swap;
	}

	return i;
}

/*
 * Return list of supported functionality.
 */
static u32 puv3_i2c_func(struct i2c_adapter *adapter)
{
	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
}

static struct i2c_algorithm puv3_i2c_algorithm = {
	.master_xfer	= puv3_i2c_xfer,
	.functionality	= puv3_i2c_func,
};

/*
 * Main initialization routine.
 */
static int puv3_i2c_probe(struct platform_device *pdev)
{
	struct i2c_adapter *adapter;
	struct resource *mem;
	int rc;

	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!mem)
		return -ENODEV;

	if (!request_mem_region(mem->start, resource_size(mem), "puv3_i2c"))
		return -EBUSY;

	adapter = kzalloc(sizeof(struct i2c_adapter), GFP_KERNEL);
	if (adapter == NULL) {
		dev_err(&pdev->dev, "can't allocate inteface!\n");
		rc = -ENOMEM;
		goto fail_nomem;
	}
	snprintf(adapter->name, sizeof(adapter->name), "PUV3-I2C at 0x%08x",
			mem->start);
	adapter->algo = &puv3_i2c_algorithm;
	adapter->class = I2C_CLASS_HWMON;
	adapter->dev.parent = &pdev->dev;

	platform_set_drvdata(pdev, adapter);

	adapter->nr = pdev->id;
	rc = i2c_add_numbered_adapter(adapter);
	if (rc) {
		dev_err(&pdev->dev, "Adapter '%s' registration failed\n",
				adapter->name);
		goto fail_add_adapter;
	}

	dev_info(&pdev->dev, "PKUnity v3 i2c bus adapter.\n");
	return 0;

fail_add_adapter:
	platform_set_drvdata(pdev, NULL);
	kfree(adapter);
fail_nomem:
	release_mem_region(mem->start, resource_size(mem));

	return rc;
}

static int puv3_i2c_remove(struct platform_device *pdev)
{
	struct i2c_adapter *adapter = platform_get_drvdata(pdev);
	struct resource *mem;
	int rc;

	rc = i2c_del_adapter(adapter);
	if (rc) {
		dev_err(&pdev->dev, "Adapter '%s' delete fail\n",
				adapter->name);
		return rc;
	}

	put_device(&pdev->dev);
	platform_set_drvdata(pdev, NULL);

	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	release_mem_region(mem->start, resource_size(mem));

	return rc;
}

#ifdef CONFIG_PM
static int puv3_i2c_suspend(struct device *dev)
{
	int poll_count;
	/* Disable the IIC */
	writel(I2C_ENABLE_DISABLE, I2C_ENABLE);
	for (poll_count = 0; poll_count < 50; poll_count++) {
		if (readl(I2C_ENSTATUS) & I2C_ENSTATUS_ENABLE)
			udelay(25);
	}

	return 0;
}

static SIMPLE_DEV_PM_OPS(puv3_i2c_pm, puv3_i2c_suspend, NULL);
#define PUV3_I2C_PM	(&puv3_i2c_pm)

#else
#define PUV3_I2C_PM	NULL
#endif

static struct platform_driver puv3_i2c_driver = {
	.probe		= puv3_i2c_probe,
	.remove		= puv3_i2c_remove,
	.driver		= {
		.name	= "PKUnity-v3-I2C",
		.owner	= THIS_MODULE,
		.pm	= PUV3_I2C_PM,
	}
};

module_platform_driver(puv3_i2c_driver);

MODULE_DESCRIPTION("PKUnity v3 I2C driver");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:puv3_i2c");
Commit	Line	Data
d10e4a66 G	1	/*
	2	* I2C driver for PKUnity-v3 SoC
	3	* Code specific to PKUnity SoC and UniCore ISA
	4	*
	5	* Maintained by GUAN Xue-tao <gxt@mprc.pku.edu.cn>
	6	* Copyright (C) 2001-2010 Guan Xuetao
	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/module.h>
	14	#include <linux/kernel.h>
	15	#include <linux/err.h>
	16	#include <linux/slab.h>
	17	#include <linux/types.h>
	18	#include <linux/delay.h>
	19	#include <linux/i2c.h>
	20	#include <linux/init.h>
	21	#include <linux/clk.h>
	22	#include <linux/platform_device.h>
	23	#include <linux/io.h>
	24	#include <mach/hardware.h>
	25
	26	/*
	27	* Poll the i2c status register until the specified bit is set.
	28	* Returns 0 if timed out (100 msec).
	29	*/
	30	static short poll_status(unsigned long bit)
	31	{
	32	int loop_cntr = 1000;
	33
	34	if (bit & I2C_STATUS_TFNF) {
	35	do {
	36	udelay(10);
	37	} while (!(readl(I2C_STATUS) & bit) && (--loop_cntr > 0));
	38	} else {
	39	/* RXRDY handler */
	40	do {
	41	if (readl(I2C_TAR) == I2C_TAR_EEPROM)
	42	msleep(20);
	43	else
	44	udelay(10);
	45	} while (!(readl(I2C_RXFLR) & 0xf) && (--loop_cntr > 0));
	46	}
	47
	48	return (loop_cntr > 0);
	49	}
	50
	51	static int xfer_read(struct i2c_adapter adap, unsigned char buf, int length)
	52	{
	53	int i2c_reg = *buf;
	54
	55	/* Read data */
	56	while (length--) {
	57	if (!poll_status(I2C_STATUS_TFNF)) {
	58	dev_dbg(&adap->dev, "Tx FIFO Not Full timeout\n");
	59	return -ETIMEDOUT;
	60	}
	61
	62	/* send addr */
	63	writel(i2c_reg \| I2C_DATACMD_WRITE, I2C_DATACMD);
	64
65	/* get ready to next write */
66	i2c_reg++;
67
68	/* send read CMD */
69	writel(I2C_DATACMD_READ, I2C_DATACMD);
70
71	/* wait until the Rx FIFO have available */
72	if (!poll_status(I2C_STATUS_RFNE)) {
73	dev_dbg(&adap->dev, "RXRDY timeout\n");
74	return -ETIMEDOUT;
75	}
76
77	/* read the data to buf */
78	*buf = (readl(I2C_DATACMD) & I2C_DATACMD_DAT_MASK);
79	buf++;
80	}
81
82	return 0;
83	}
84
85	static int xfer_write(struct i2c_adapter adap, unsigned char buf, int length)
86	{
87	int i2c_reg = *buf;
88
89	/* Do nothing but storing the reg_num to a static variable */
90	if (i2c_reg == -1) {
91	printk(KERN_WARNING "Error i2c reg\n");
92	return -ETIMEDOUT;
93	}
94
95	if (length == 1)
96	return 0;
97
98	buf++;
99	length--;
100	while (length--) {
101	/* send addr */
102	writel(i2c_reg \| I2C_DATACMD_WRITE, I2C_DATACMD);
103
104	/* send write CMD */
105	writel(*buf \| I2C_DATACMD_WRITE, I2C_DATACMD);
106
107	/* wait until the Rx FIFO have available */
108	msleep(20);
109
110	/* read the data to buf */
111	i2c_reg++;
112	buf++;
113	}
114
115	return 0;
116	}
117
118	/*
119	* Generic i2c master transfer entrypoint.
120	*
121	*/
122	static int puv3_i2c_xfer(struct i2c_adapter adap, struct i2c_msg pmsg,
123	int num)
124	{
125	int i, ret;
126	unsigned char swap;
127
128	/* Disable i2c */
129	writel(I2C_ENABLE_DISABLE, I2C_ENABLE);
130
131	/* Set the work mode and speed*/
132	writel(I2C_CON_MASTER \| I2C_CON_SPEED_STD \| I2C_CON_SLAVEDISABLE, I2C_CON);
133
134	writel(pmsg->addr, I2C_TAR);
135
136	/* Enable i2c */
137	writel(I2C_ENABLE_ENABLE, I2C_ENABLE);
138
139	dev_dbg(&adap->dev, "puv3_i2c_xfer: processing %d messages:\n", num);
140
141	for (i = 0; i < num; i++) {
142	dev_dbg(&adap->dev, " #%d: %sing %d byte%s %s 0x%02x\n", i,
143	pmsg->flags & I2C_M_RD ? "read" : "writ",
144	pmsg->len, pmsg->len > 1 ? "s" : "",
145	pmsg->flags & I2C_M_RD ? "from" : "to", pmsg->addr);
146
147	if (pmsg->len && pmsg->buf) { /* sanity check */
148	if (pmsg->flags & I2C_M_RD)
149	ret = xfer_read(adap, pmsg->buf, pmsg->len);
150	else
151	ret = xfer_write(adap, pmsg->buf, pmsg->len);
152
153	if (ret)
154	return ret;
155
156	}
157	dev_dbg(&adap->dev, "transfer complete\n");
158	pmsg++; /* next message */
159	}
160
161	/* XXX: fixup be16_to_cpu in bq27x00_battery.c */
162	if (pmsg->addr == I2C_TAR_PWIC) {
163	swap = pmsg->buf[0];
164	pmsg->buf[0] = pmsg->buf[1];
165	pmsg->buf[1] = swap;
166	}
167
168	return i;
169	}
170
171	/*
172	* Return list of supported functionality.
173	*/
174	static u32 puv3_i2c_func(struct i2c_adapter *adapter)
175	{
176	return I2C_FUNC_I2C \| I2C_FUNC_SMBUS_EMUL;
177	}
178
179	static struct i2c_algorithm puv3_i2c_algorithm = {
180	.master_xfer = puv3_i2c_xfer,
181	.functionality = puv3_i2c_func,
182	};
183
184	/*
185	* Main initialization routine.
186	*/
0b255e92	187	static int puv3_i2c_probe(struct platform_device *pdev)
d10e4a66 G	188	{
	189	struct i2c_adapter *adapter;
	190	struct resource *mem;
	191	int rc;
	192
	193	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	194	if (!mem)
	195	return -ENODEV;
	196
	197	if (!request_mem_region(mem->start, resource_size(mem), "puv3_i2c"))
	198	return -EBUSY;
	199
	200	adapter = kzalloc(sizeof(struct i2c_adapter), GFP_KERNEL);
	201	if (adapter == NULL) {
	202	dev_err(&pdev->dev, "can't allocate inteface!\n");
	203	rc = -ENOMEM;
	204	goto fail_nomem;
	205	}
	206	snprintf(adapter->name, sizeof(adapter->name), "PUV3-I2C at 0x%08x",
	207	mem->start);
	208	adapter->algo = &puv3_i2c_algorithm;
	209	adapter->class = I2C_CLASS_HWMON;
	210	adapter->dev.parent = &pdev->dev;
	211
	212	platform_set_drvdata(pdev, adapter);
	213
	214	adapter->nr = pdev->id;
	215	rc = i2c_add_numbered_adapter(adapter);
	216	if (rc) {
	217	dev_err(&pdev->dev, "Adapter '%s' registration failed\n",
	218	adapter->name);
	219	goto fail_add_adapter;
	220	}
	221
	222	dev_info(&pdev->dev, "PKUnity v3 i2c bus adapter.\n");
	223	return 0;
	224
	225	fail_add_adapter:
	226	platform_set_drvdata(pdev, NULL);
	227	kfree(adapter);
	228	fail_nomem:
	229	release_mem_region(mem->start, resource_size(mem));
	230
	231	return rc;
	232	}
	233
0b255e92	234	static int puv3_i2c_remove(struct platform_device *pdev)
d10e4a66 G	235	{
	236	struct i2c_adapter *adapter = platform_get_drvdata(pdev);
	237	struct resource *mem;
	238	int rc;
	239
	240	rc = i2c_del_adapter(adapter);
	241	if (rc) {
	242	dev_err(&pdev->dev, "Adapter '%s' delete fail\n",
	243	adapter->name);
	244	return rc;
	245	}
	246
	247	put_device(&pdev->dev);
	248	platform_set_drvdata(pdev, NULL);
	249
	250	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	251	release_mem_region(mem->start, resource_size(mem));
	252
	253	return rc;
	254	}
	255
	256	#ifdef CONFIG_PM
b9f1b45b	257	static int puv3_i2c_suspend(struct device *dev)
d10e4a66 G	258	{
	259	int poll_count;
	260	/* Disable the IIC */
	261	writel(I2C_ENABLE_DISABLE, I2C_ENABLE);
	262	for (poll_count = 0; poll_count < 50; poll_count++) {
	263	if (readl(I2C_ENSTATUS) & I2C_ENSTATUS_ENABLE)
	264	udelay(25);
	265	}
	266
	267	return 0;
	268	}
	269
b9f1b45b RW	270	static SIMPLE_DEV_PM_OPS(puv3_i2c_pm, puv3_i2c_suspend, NULL);
	271	#define PUV3_I2C_PM (&puv3_i2c_pm)
	272
d10e4a66	273	#else
b9f1b45b	274	#define PUV3_I2C_PM NULL
d10e4a66 G	275	#endif
d10e4a66 G	276
d10e4a66 G	277	static struct platform_driver puv3_i2c_driver = {
d10e4a66 G	278	.probe = puv3_i2c_probe,
0b255e92	279	.remove = puv3_i2c_remove,
d10e4a66 G	280	.driver = {
	281	.name = "PKUnity-v3-I2C",
	282	.owner = THIS_MODULE,
b9f1b45b	283	.pm = PUV3_I2C_PM,
d10e4a66 G	284	}
	285	};
	286
858af58f	287	module_platform_driver(puv3_i2c_driver);
d10e4a66 G	288
	289	MODULE_DESCRIPTION("PKUnity v3 I2C driver");
	290	MODULE_LICENSE("GPL v2");
858af58f	291	MODULE_ALIAS("platform:puv3_i2c");