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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/i2c/busses/i2c-sis96x.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/i2c/busses/i2c-sis96x.c')
-rw-r--r--drivers/i2c/busses/i2c-sis96x.c358
1 files changed, 358 insertions, 0 deletions
diff --git a/drivers/i2c/busses/i2c-sis96x.c b/drivers/i2c/busses/i2c-sis96x.c
new file mode 100644
index 000000000000..3cac6d43bce5
--- /dev/null
+++ b/drivers/i2c/busses/i2c-sis96x.c
@@ -0,0 +1,358 @@
1/*
2 sis96x.c - Part of lm_sensors, Linux kernel modules for hardware
3 monitoring
4
5 Copyright (c) 2003 Mark M. Hoffman <mhoffman@lightlink.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 as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20*/
21
22/*
23 This module must be considered BETA unless and until
24 the chipset manufacturer releases a datasheet.
25 The register definitions are based on the SiS630.
26
27 This module relies on quirk_sis_96x_smbus (drivers/pci/quirks.c)
28 for just about every machine for which users have reported.
29 If this module isn't detecting your 96x south bridge, have a
30 look there.
31
32 We assume there can only be one SiS96x with one SMBus interface.
33*/
34
35#include <linux/config.h>
36#include <linux/module.h>
37#include <linux/pci.h>
38#include <linux/kernel.h>
39#include <linux/delay.h>
40#include <linux/stddef.h>
41#include <linux/sched.h>
42#include <linux/ioport.h>
43#include <linux/i2c.h>
44#include <linux/init.h>
45#include <asm/io.h>
46
47/*
48 HISTORY:
49 2003-05-11 1.0.0 Updated from lm_sensors project for kernel 2.5
50 (was i2c-sis645.c from lm_sensors 2.7.0)
51*/
52#define SIS96x_VERSION "1.0.0"
53
54/* base address register in PCI config space */
55#define SIS96x_BAR 0x04
56
57/* SiS96x SMBus registers */
58#define SMB_STS 0x00
59#define SMB_EN 0x01
60#define SMB_CNT 0x02
61#define SMB_HOST_CNT 0x03
62#define SMB_ADDR 0x04
63#define SMB_CMD 0x05
64#define SMB_PCOUNT 0x06
65#define SMB_COUNT 0x07
66#define SMB_BYTE 0x08
67#define SMB_DEV_ADDR 0x10
68#define SMB_DB0 0x11
69#define SMB_DB1 0x12
70#define SMB_SAA 0x13
71
72/* register count for request_region */
73#define SMB_IOSIZE 0x20
74
75/* Other settings */
76#define MAX_TIMEOUT 500
77
78/* SiS96x SMBus constants */
79#define SIS96x_QUICK 0x00
80#define SIS96x_BYTE 0x01
81#define SIS96x_BYTE_DATA 0x02
82#define SIS96x_WORD_DATA 0x03
83#define SIS96x_PROC_CALL 0x04
84#define SIS96x_BLOCK_DATA 0x05
85
86static struct i2c_adapter sis96x_adapter;
87static u16 sis96x_smbus_base = 0;
88
89static inline u8 sis96x_read(u8 reg)
90{
91 return inb(sis96x_smbus_base + reg) ;
92}
93
94static inline void sis96x_write(u8 reg, u8 data)
95{
96 outb(data, sis96x_smbus_base + reg) ;
97}
98
99/* Execute a SMBus transaction.
100 int size is from SIS96x_QUICK to SIS96x_BLOCK_DATA
101 */
102static int sis96x_transaction(int size)
103{
104 int temp;
105 int result = 0;
106 int timeout = 0;
107
108 dev_dbg(&sis96x_adapter.dev, "SMBus transaction %d\n", size);
109
110 /* Make sure the SMBus host is ready to start transmitting */
111 if (((temp = sis96x_read(SMB_CNT)) & 0x03) != 0x00) {
112
113 dev_dbg(&sis96x_adapter.dev, "SMBus busy (0x%02x). "
114 "Resetting...\n", temp);
115
116 /* kill the transaction */
117 sis96x_write(SMB_HOST_CNT, 0x20);
118
119 /* check it again */
120 if (((temp = sis96x_read(SMB_CNT)) & 0x03) != 0x00) {
121 dev_dbg(&sis96x_adapter.dev, "Failed (0x%02x)\n", temp);
122 return -1;
123 } else {
124 dev_dbg(&sis96x_adapter.dev, "Successful\n");
125 }
126 }
127
128 /* Turn off timeout interrupts, set fast host clock */
129 sis96x_write(SMB_CNT, 0x20);
130
131 /* clear all (sticky) status flags */
132 temp = sis96x_read(SMB_STS);
133 sis96x_write(SMB_STS, temp & 0x1e);
134
135 /* start the transaction by setting bit 4 and size bits */
136 sis96x_write(SMB_HOST_CNT, 0x10 | (size & 0x07));
137
138 /* We will always wait for a fraction of a second! */
139 do {
140 msleep(1);
141 temp = sis96x_read(SMB_STS);
142 } while (!(temp & 0x0e) && (timeout++ < MAX_TIMEOUT));
143
144 /* If the SMBus is still busy, we give up */
145 if (timeout >= MAX_TIMEOUT) {
146 dev_dbg(&sis96x_adapter.dev, "SMBus Timeout! (0x%02x)\n", temp);
147 result = -1;
148 }
149
150 /* device error - probably missing ACK */
151 if (temp & 0x02) {
152 dev_dbg(&sis96x_adapter.dev, "Failed bus transaction!\n");
153 result = -1;
154 }
155
156 /* bus collision */
157 if (temp & 0x04) {
158 dev_dbg(&sis96x_adapter.dev, "Bus collision!\n");
159 result = -1;
160 }
161
162 /* Finish up by resetting the bus */
163 sis96x_write(SMB_STS, temp);
164 if ((temp = sis96x_read(SMB_STS))) {
165 dev_dbg(&sis96x_adapter.dev, "Failed reset at "
166 "end of transaction! (0x%02x)\n", temp);
167 }
168
169 return result;
170}
171
172/* Return -1 on error. */
173static s32 sis96x_access(struct i2c_adapter * adap, u16 addr,
174 unsigned short flags, char read_write,
175 u8 command, int size, union i2c_smbus_data * data)
176{
177
178 switch (size) {
179 case I2C_SMBUS_QUICK:
180 sis96x_write(SMB_ADDR, ((addr & 0x7f) << 1) | (read_write & 0x01));
181 size = SIS96x_QUICK;
182 break;
183
184 case I2C_SMBUS_BYTE:
185 sis96x_write(SMB_ADDR, ((addr & 0x7f) << 1) | (read_write & 0x01));
186 if (read_write == I2C_SMBUS_WRITE)
187 sis96x_write(SMB_CMD, command);
188 size = SIS96x_BYTE;
189 break;
190
191 case I2C_SMBUS_BYTE_DATA:
192 sis96x_write(SMB_ADDR, ((addr & 0x7f) << 1) | (read_write & 0x01));
193 sis96x_write(SMB_CMD, command);
194 if (read_write == I2C_SMBUS_WRITE)
195 sis96x_write(SMB_BYTE, data->byte);
196 size = SIS96x_BYTE_DATA;
197 break;
198
199 case I2C_SMBUS_PROC_CALL:
200 case I2C_SMBUS_WORD_DATA:
201 sis96x_write(SMB_ADDR, ((addr & 0x7f) << 1) | (read_write & 0x01));
202 sis96x_write(SMB_CMD, command);
203 if (read_write == I2C_SMBUS_WRITE) {
204 sis96x_write(SMB_BYTE, data->word & 0xff);
205 sis96x_write(SMB_BYTE + 1, (data->word & 0xff00) >> 8);
206 }
207 size = (size == I2C_SMBUS_PROC_CALL ?
208 SIS96x_PROC_CALL : SIS96x_WORD_DATA);
209 break;
210
211 case I2C_SMBUS_BLOCK_DATA:
212 /* TO DO: */
213 dev_info(&adap->dev, "SMBus block not implemented!\n");
214 return -1;
215 break;
216
217 default:
218 dev_info(&adap->dev, "Unsupported I2C size\n");
219 return -1;
220 break;
221 }
222
223 if (sis96x_transaction(size))
224 return -1;
225
226 if ((size != SIS96x_PROC_CALL) &&
227 ((read_write == I2C_SMBUS_WRITE) || (size == SIS96x_QUICK)))
228 return 0;
229
230 switch (size) {
231 case SIS96x_BYTE:
232 case SIS96x_BYTE_DATA:
233 data->byte = sis96x_read(SMB_BYTE);
234 break;
235
236 case SIS96x_WORD_DATA:
237 case SIS96x_PROC_CALL:
238 data->word = sis96x_read(SMB_BYTE) +
239 (sis96x_read(SMB_BYTE + 1) << 8);
240 break;
241 }
242 return 0;
243}
244
245static u32 sis96x_func(struct i2c_adapter *adapter)
246{
247 return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
248 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
249 I2C_FUNC_SMBUS_PROC_CALL;
250}
251
252static struct i2c_algorithm smbus_algorithm = {
253 .name = "Non-I2C SMBus adapter",
254 .id = I2C_ALGO_SMBUS,
255 .smbus_xfer = sis96x_access,
256 .functionality = sis96x_func,
257};
258
259static struct i2c_adapter sis96x_adapter = {
260 .owner = THIS_MODULE,
261 .class = I2C_CLASS_HWMON,
262 .algo = &smbus_algorithm,
263 .name = "unset",
264};
265
266static struct pci_device_id sis96x_ids[] = {
267 { PCI_DEVICE(PCI_VENDOR_ID_SI, PCI_DEVICE_ID_SI_SMBUS) },
268 { 0, }
269};
270
271MODULE_DEVICE_TABLE (pci, sis96x_ids);
272
273static int __devinit sis96x_probe(struct pci_dev *dev,
274 const struct pci_device_id *id)
275{
276 u16 ww = 0;
277 int retval;
278
279 if (sis96x_smbus_base) {
280 dev_err(&dev->dev, "Only one device supported.\n");
281 return -EBUSY;
282 }
283
284 pci_read_config_word(dev, PCI_CLASS_DEVICE, &ww);
285 if (PCI_CLASS_SERIAL_SMBUS != ww) {
286 dev_err(&dev->dev, "Unsupported device class 0x%04x!\n", ww);
287 return -ENODEV;
288 }
289
290 sis96x_smbus_base = pci_resource_start(dev, SIS96x_BAR);
291 if (!sis96x_smbus_base) {
292 dev_err(&dev->dev, "SiS96x SMBus base address "
293 "not initialized!\n");
294 return -EINVAL;
295 }
296 dev_info(&dev->dev, "SiS96x SMBus base address: 0x%04x\n",
297 sis96x_smbus_base);
298
299 /* Everything is happy, let's grab the memory and set things up. */
300 if (!request_region(sis96x_smbus_base, SMB_IOSIZE, "sis96x-smbus")) {
301 dev_err(&dev->dev, "SMBus registers 0x%04x-0x%04x "
302 "already in use!\n", sis96x_smbus_base,
303 sis96x_smbus_base + SMB_IOSIZE - 1);
304
305 sis96x_smbus_base = 0;
306 return -EINVAL;
307 }
308
309 /* set up the driverfs linkage to our parent device */
310 sis96x_adapter.dev.parent = &dev->dev;
311
312 snprintf(sis96x_adapter.name, I2C_NAME_SIZE,
313 "SiS96x SMBus adapter at 0x%04x", sis96x_smbus_base);
314
315 if ((retval = i2c_add_adapter(&sis96x_adapter))) {
316 dev_err(&dev->dev, "Couldn't register adapter!\n");
317 release_region(sis96x_smbus_base, SMB_IOSIZE);
318 sis96x_smbus_base = 0;
319 }
320
321 return retval;
322}
323
324static void __devexit sis96x_remove(struct pci_dev *dev)
325{
326 if (sis96x_smbus_base) {
327 i2c_del_adapter(&sis96x_adapter);
328 release_region(sis96x_smbus_base, SMB_IOSIZE);
329 sis96x_smbus_base = 0;
330 }
331}
332
333static struct pci_driver sis96x_driver = {
334 .name = "sis96x_smbus",
335 .id_table = sis96x_ids,
336 .probe = sis96x_probe,
337 .remove = __devexit_p(sis96x_remove),
338};
339
340static int __init i2c_sis96x_init(void)
341{
342 printk(KERN_INFO "i2c-sis96x version %s\n", SIS96x_VERSION);
343 return pci_register_driver(&sis96x_driver);
344}
345
346static void __exit i2c_sis96x_exit(void)
347{
348 pci_unregister_driver(&sis96x_driver);
349}
350
351MODULE_AUTHOR("Mark M. Hoffman <mhoffman@lightlink.com>");
352MODULE_DESCRIPTION("SiS96x SMBus driver");
353MODULE_LICENSE("GPL");
354
355/* Register initialization functions using helper macros */
356module_init(i2c_sis96x_init);
357module_exit(i2c_sis96x_exit);
358