xref: /linux/drivers/mfd/88pm860x-i2c.c (revision d39d0ed196aa1685bb24771e92f78633c66ac9cb)
1 /*
2  * I2C driver for Marvell 88PM860x
3  *
4  * Copyright (C) 2009 Marvell International Ltd.
5  * 	Haojian Zhuang <haojian.zhuang@marvell.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/platform_device.h>
14 #include <linux/i2c.h>
15 #include <linux/mfd/88pm860x.h>
16 #include <linux/slab.h>
17 
18 static inline int pm860x_read_device(struct i2c_client *i2c,
19 				     int reg, int bytes, void *dest)
20 {
21 	unsigned char data;
22 	int ret;
23 
24 	data = (unsigned char)reg;
25 	ret = i2c_master_send(i2c, &data, 1);
26 	if (ret < 0)
27 		return ret;
28 
29 	ret = i2c_master_recv(i2c, dest, bytes);
30 	if (ret < 0)
31 		return ret;
32 	return 0;
33 }
34 
35 static inline int pm860x_write_device(struct i2c_client *i2c,
36 				      int reg, int bytes, void *src)
37 {
38 	unsigned char buf[bytes + 1];
39 	int ret;
40 
41 	buf[0] = (unsigned char)reg;
42 	memcpy(&buf[1], src, bytes);
43 
44 	ret = i2c_master_send(i2c, buf, bytes + 1);
45 	if (ret < 0)
46 		return ret;
47 	return 0;
48 }
49 
50 int pm860x_reg_read(struct i2c_client *i2c, int reg)
51 {
52 	struct pm860x_chip *chip = i2c_get_clientdata(i2c);
53 	unsigned char data;
54 	int ret;
55 
56 	mutex_lock(&chip->io_lock);
57 	ret = pm860x_read_device(i2c, reg, 1, &data);
58 	mutex_unlock(&chip->io_lock);
59 
60 	if (ret < 0)
61 		return ret;
62 	else
63 		return (int)data;
64 }
65 EXPORT_SYMBOL(pm860x_reg_read);
66 
67 int pm860x_reg_write(struct i2c_client *i2c, int reg,
68 		     unsigned char data)
69 {
70 	struct pm860x_chip *chip = i2c_get_clientdata(i2c);
71 	int ret;
72 
73 	mutex_lock(&chip->io_lock);
74 	ret = pm860x_write_device(i2c, reg, 1, &data);
75 	mutex_unlock(&chip->io_lock);
76 
77 	return ret;
78 }
79 EXPORT_SYMBOL(pm860x_reg_write);
80 
81 int pm860x_bulk_read(struct i2c_client *i2c, int reg,
82 		     int count, unsigned char *buf)
83 {
84 	struct pm860x_chip *chip = i2c_get_clientdata(i2c);
85 	int ret;
86 
87 	mutex_lock(&chip->io_lock);
88 	ret = pm860x_read_device(i2c, reg, count, buf);
89 	mutex_unlock(&chip->io_lock);
90 
91 	return ret;
92 }
93 EXPORT_SYMBOL(pm860x_bulk_read);
94 
95 int pm860x_bulk_write(struct i2c_client *i2c, int reg,
96 		      int count, unsigned char *buf)
97 {
98 	struct pm860x_chip *chip = i2c_get_clientdata(i2c);
99 	int ret;
100 
101 	mutex_lock(&chip->io_lock);
102 	ret = pm860x_write_device(i2c, reg, count, buf);
103 	mutex_unlock(&chip->io_lock);
104 
105 	return ret;
106 }
107 EXPORT_SYMBOL(pm860x_bulk_write);
108 
109 int pm860x_set_bits(struct i2c_client *i2c, int reg,
110 		    unsigned char mask, unsigned char data)
111 {
112 	struct pm860x_chip *chip = i2c_get_clientdata(i2c);
113 	unsigned char value;
114 	int ret;
115 
116 	mutex_lock(&chip->io_lock);
117 	ret = pm860x_read_device(i2c, reg, 1, &value);
118 	if (ret < 0)
119 		goto out;
120 	value &= ~mask;
121 	value |= data;
122 	ret = pm860x_write_device(i2c, reg, 1, &value);
123 out:
124 	mutex_unlock(&chip->io_lock);
125 	return ret;
126 }
127 EXPORT_SYMBOL(pm860x_set_bits);
128 
129 
130 static const struct i2c_device_id pm860x_id_table[] = {
131 	{ "88PM860x", 0 },
132 	{}
133 };
134 MODULE_DEVICE_TABLE(i2c, pm860x_id_table);
135 
136 static int verify_addr(struct i2c_client *i2c)
137 {
138 	unsigned short addr_8607[] = {0x30, 0x34};
139 	unsigned short addr_8606[] = {0x10, 0x11};
140 	int size, i;
141 
142 	if (i2c == NULL)
143 		return 0;
144 	size = ARRAY_SIZE(addr_8606);
145 	for (i = 0; i < size; i++) {
146 		if (i2c->addr == *(addr_8606 + i))
147 			return CHIP_PM8606;
148 	}
149 	size = ARRAY_SIZE(addr_8607);
150 	for (i = 0; i < size; i++) {
151 		if (i2c->addr == *(addr_8607 + i))
152 			return CHIP_PM8607;
153 	}
154 	return 0;
155 }
156 
157 static int __devinit pm860x_probe(struct i2c_client *client,
158 				  const struct i2c_device_id *id)
159 {
160 	struct pm860x_platform_data *pdata = client->dev.platform_data;
161 	struct pm860x_chip *chip;
162 
163 	if (!pdata) {
164 		pr_info("No platform data in %s!\n", __func__);
165 		return -EINVAL;
166 	}
167 
168 	chip = kzalloc(sizeof(struct pm860x_chip), GFP_KERNEL);
169 	if (chip == NULL)
170 		return -ENOMEM;
171 
172 	chip->id = verify_addr(client);
173 	chip->client = client;
174 	i2c_set_clientdata(client, chip);
175 	chip->dev = &client->dev;
176 	mutex_init(&chip->io_lock);
177 	dev_set_drvdata(chip->dev, chip);
178 
179 	/*
180 	 * Both client and companion client shares same platform driver.
181 	 * Driver distinguishes them by pdata->companion_addr.
182 	 * pdata->companion_addr is only assigned if companion chip exists.
183 	 * At the same time, the companion_addr shouldn't equal to client
184 	 * address.
185 	 */
186 	if (pdata->companion_addr && (pdata->companion_addr != client->addr)) {
187 		chip->companion_addr = pdata->companion_addr;
188 		chip->companion = i2c_new_dummy(chip->client->adapter,
189 						chip->companion_addr);
190 		i2c_set_clientdata(chip->companion, chip);
191 	}
192 
193 	pm860x_device_init(chip, pdata);
194 	return 0;
195 }
196 
197 static int __devexit pm860x_remove(struct i2c_client *client)
198 {
199 	struct pm860x_chip *chip = i2c_get_clientdata(client);
200 
201 	pm860x_device_exit(chip);
202 	i2c_unregister_device(chip->companion);
203 	kfree(chip);
204 	return 0;
205 }
206 
207 static struct i2c_driver pm860x_driver = {
208 	.driver	= {
209 		.name	= "88PM860x",
210 		.owner	= THIS_MODULE,
211 	},
212 	.probe		= pm860x_probe,
213 	.remove		= __devexit_p(pm860x_remove),
214 	.id_table	= pm860x_id_table,
215 };
216 
217 static int __init pm860x_i2c_init(void)
218 {
219 	int ret;
220 	ret = i2c_add_driver(&pm860x_driver);
221 	if (ret != 0)
222 		pr_err("Failed to register 88PM860x I2C driver: %d\n", ret);
223 	return ret;
224 }
225 subsys_initcall(pm860x_i2c_init);
226 
227 static void __exit pm860x_i2c_exit(void)
228 {
229 	i2c_del_driver(&pm860x_driver);
230 }
231 module_exit(pm860x_i2c_exit);
232 
233 MODULE_DESCRIPTION("I2C Driver for Marvell 88PM860x");
234 MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
235 MODULE_LICENSE("GPL");
236