blob: 81520868797b84e8f3915a8c23360660c7291022 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 i2c-via.c - Part of lm_sensors, Linux kernel modules
3 for hardware monitoring
4
5 i2c Support for Via Technologies 82C586B South Bridge
6
7 Copyright (c) 1998, 1999 Kyösti Mälkki <kmalkki@cc.hut.fi>
8
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2 of the License, or
12 (at your option) any later version.
13
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
18
19 You should have received a copy of the GNU General Public License
20 along with this program; if not, write to the Free Software
21 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22*/
23
Linus Torvalds1da177e2005-04-16 15:20:36 -070024#include <linux/kernel.h>
25#include <linux/module.h>
26#include <linux/pci.h>
27#include <linux/ioport.h>
28#include <linux/init.h>
29#include <linux/i2c.h>
30#include <linux/i2c-algo-bit.h>
31#include <asm/io.h>
32
33/* Power management registers */
34#define PM_CFG_REVID 0x08 /* silicon revision code */
35#define PM_CFG_IOBASE0 0x20
36#define PM_CFG_IOBASE1 0x48
37
38#define I2C_DIR (pm_io_base+0x40)
39#define I2C_OUT (pm_io_base+0x42)
40#define I2C_IN (pm_io_base+0x44)
41#define I2C_SCL 0x02 /* clock bit in DIR/OUT/IN register */
42#define I2C_SDA 0x04
43
44/* io-region reservation */
45#define IOSPACE 0x06
Linus Torvalds1da177e2005-04-16 15:20:36 -070046
Jean Delvared6072f82005-09-25 16:37:04 +020047static struct pci_driver vt586b_driver;
Jean Delvare60507092005-09-25 16:23:07 +020048static u16 pm_io_base;
Linus Torvalds1da177e2005-04-16 15:20:36 -070049
50/*
51 It does not appear from the datasheet that the GPIO pins are
52 open drain. So a we set a low value by setting the direction to
53 output and a high value by setting the direction to input and
54 relying on the required I2C pullup. The data value is initialized
55 to 0 in via_init() and never changed.
56*/
57static void bit_via_setscl(void *data, int state)
58{
59 outb(state ? inb(I2C_DIR) & ~I2C_SCL : inb(I2C_DIR) | I2C_SCL, I2C_DIR);
60}
61
62static void bit_via_setsda(void *data, int state)
63{
64 outb(state ? inb(I2C_DIR) & ~I2C_SDA : inb(I2C_DIR) | I2C_SDA, I2C_DIR);
65}
66
67static int bit_via_getscl(void *data)
68{
69 return (0 != (inb(I2C_IN) & I2C_SCL));
70}
71
72static int bit_via_getsda(void *data)
73{
74 return (0 != (inb(I2C_IN) & I2C_SDA));
75}
76
77
78static struct i2c_algo_bit_data bit_data = {
79 .setsda = bit_via_setsda,
80 .setscl = bit_via_setscl,
81 .getsda = bit_via_getsda,
82 .getscl = bit_via_getscl,
83 .udelay = 5,
Linus Torvalds1da177e2005-04-16 15:20:36 -070084 .timeout = HZ
85};
86
87static struct i2c_adapter vt586b_adapter = {
88 .owner = THIS_MODULE,
Stephen Hemminger9ace5552007-02-13 22:09:01 +010089 .id = I2C_HW_B_VIA,
Linus Torvalds1da177e2005-04-16 15:20:36 -070090 .class = I2C_CLASS_HWMON,
91 .name = "VIA i2c",
92 .algo_data = &bit_data,
93};
94
95
96static struct pci_device_id vt586b_ids[] __devinitdata = {
97 { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C586_3) },
98 { 0, }
99};
100
101MODULE_DEVICE_TABLE (pci, vt586b_ids);
102
103static int __devinit vt586b_probe(struct pci_dev *dev, const struct pci_device_id *id)
104{
105 u16 base;
106 u8 rev;
107 int res;
108
109 if (pm_io_base) {
110 dev_err(&dev->dev, "i2c-via: Will only support one host\n");
111 return -ENODEV;
112 }
113
114 pci_read_config_byte(dev, PM_CFG_REVID, &rev);
115
116 switch (rev) {
117 case 0x00:
118 base = PM_CFG_IOBASE0;
119 break;
120 case 0x01:
121 case 0x10:
122 base = PM_CFG_IOBASE1;
123 break;
124
125 default:
126 base = PM_CFG_IOBASE1;
127 /* later revision */
128 }
129
130 pci_read_config_word(dev, base, &pm_io_base);
131 pm_io_base &= (0xff << 8);
132
Jean Delvared6072f82005-09-25 16:37:04 +0200133 if (!request_region(I2C_DIR, IOSPACE, vt586b_driver.name)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134 dev_err(&dev->dev, "IO 0x%x-0x%x already in use\n", I2C_DIR, I2C_DIR + IOSPACE);
135 return -ENODEV;
136 }
137
138 outb(inb(I2C_DIR) & ~(I2C_SDA | I2C_SCL), I2C_DIR);
139 outb(inb(I2C_OUT) & ~(I2C_SDA | I2C_SCL), I2C_OUT);
140
Robert P. J. Day405ae7d2007-02-17 19:13:42 +0100141 /* set up the sysfs linkage to our parent device */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700142 vt586b_adapter.dev.parent = &dev->dev;
143
144 res = i2c_bit_add_bus(&vt586b_adapter);
145 if ( res < 0 ) {
146 release_region(I2C_DIR, IOSPACE);
147 pm_io_base = 0;
148 return res;
149 }
150 return 0;
151}
152
153static void __devexit vt586b_remove(struct pci_dev *dev)
154{
Jean Delvare32697112006-12-10 21:21:33 +0100155 i2c_del_adapter(&vt586b_adapter);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156 release_region(I2C_DIR, IOSPACE);
157 pm_io_base = 0;
158}
159
160
161static struct pci_driver vt586b_driver = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700162 .name = "vt586b_smbus",
163 .id_table = vt586b_ids,
164 .probe = vt586b_probe,
165 .remove = __devexit_p(vt586b_remove),
166};
167
168static int __init i2c_vt586b_init(void)
169{
170 return pci_register_driver(&vt586b_driver);
171}
172
173static void __exit i2c_vt586b_exit(void)
174{
175 pci_unregister_driver(&vt586b_driver);
176}
177
178
179MODULE_AUTHOR("Kyösti Mälkki <kmalkki@cc.hut.fi>");
180MODULE_DESCRIPTION("i2c for Via vt82c586b southbridge");
181MODULE_LICENSE("GPL");
182
183module_init(i2c_vt586b_init);
184module_exit(i2c_vt586b_exit);