2 sis96x.c - Part of lm_sensors, Linux kernel modules for hardware
5 Copyright (c) 2003 Mark M. Hoffman <mhoffman@lightlink.com>
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.
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.
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.
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.
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
32 We assume there can only be one SiS96x with one SMBus interface.
35 #include <linux/module.h>
36 #include <linux/pci.h>
37 #include <linux/kernel.h>
38 #include <linux/delay.h>
39 #include <linux/stddef.h>
40 #include <linux/ioport.h>
41 #include <linux/i2c.h>
42 #include <linux/init.h>
45 /* base address register in PCI config space */
46 #define SIS96x_BAR 0x04
48 /* SiS96x SMBus registers */
52 #define SMB_HOST_CNT 0x03
55 #define SMB_PCOUNT 0x06
56 #define SMB_COUNT 0x07
58 #define SMB_DEV_ADDR 0x10
63 /* register count for request_region */
64 #define SMB_IOSIZE 0x20
67 #define MAX_TIMEOUT 500
69 /* SiS96x SMBus constants */
70 #define SIS96x_QUICK 0x00
71 #define SIS96x_BYTE 0x01
72 #define SIS96x_BYTE_DATA 0x02
73 #define SIS96x_WORD_DATA 0x03
74 #define SIS96x_PROC_CALL 0x04
75 #define SIS96x_BLOCK_DATA 0x05
77 static struct pci_driver sis96x_driver
;
78 static struct i2c_adapter sis96x_adapter
;
79 static u16 sis96x_smbus_base
;
81 static inline u8
sis96x_read(u8 reg
)
83 return inb(sis96x_smbus_base
+ reg
) ;
86 static inline void sis96x_write(u8 reg
, u8 data
)
88 outb(data
, sis96x_smbus_base
+ reg
) ;
91 /* Execute a SMBus transaction.
92 int size is from SIS96x_QUICK to SIS96x_BLOCK_DATA
94 static int sis96x_transaction(int size
)
100 dev_dbg(&sis96x_adapter
.dev
, "SMBus transaction %d\n", size
);
102 /* Make sure the SMBus host is ready to start transmitting */
103 if (((temp
= sis96x_read(SMB_CNT
)) & 0x03) != 0x00) {
105 dev_dbg(&sis96x_adapter
.dev
, "SMBus busy (0x%02x). "
106 "Resetting...\n", temp
);
108 /* kill the transaction */
109 sis96x_write(SMB_HOST_CNT
, 0x20);
112 if (((temp
= sis96x_read(SMB_CNT
)) & 0x03) != 0x00) {
113 dev_dbg(&sis96x_adapter
.dev
, "Failed (0x%02x)\n", temp
);
116 dev_dbg(&sis96x_adapter
.dev
, "Successful\n");
120 /* Turn off timeout interrupts, set fast host clock */
121 sis96x_write(SMB_CNT
, 0x20);
123 /* clear all (sticky) status flags */
124 temp
= sis96x_read(SMB_STS
);
125 sis96x_write(SMB_STS
, temp
& 0x1e);
127 /* start the transaction by setting bit 4 and size bits */
128 sis96x_write(SMB_HOST_CNT
, 0x10 | (size
& 0x07));
130 /* We will always wait for a fraction of a second! */
133 temp
= sis96x_read(SMB_STS
);
134 } while (!(temp
& 0x0e) && (timeout
++ < MAX_TIMEOUT
));
136 /* If the SMBus is still busy, we give up */
137 if (timeout
>= MAX_TIMEOUT
) {
138 dev_dbg(&sis96x_adapter
.dev
, "SMBus Timeout! (0x%02x)\n", temp
);
142 /* device error - probably missing ACK */
144 dev_dbg(&sis96x_adapter
.dev
, "Failed bus transaction!\n");
150 dev_dbg(&sis96x_adapter
.dev
, "Bus collision!\n");
154 /* Finish up by resetting the bus */
155 sis96x_write(SMB_STS
, temp
);
156 if ((temp
= sis96x_read(SMB_STS
))) {
157 dev_dbg(&sis96x_adapter
.dev
, "Failed reset at "
158 "end of transaction! (0x%02x)\n", temp
);
164 /* Return negative errno on error. */
165 static s32
sis96x_access(struct i2c_adapter
* adap
, u16 addr
,
166 unsigned short flags
, char read_write
,
167 u8 command
, int size
, union i2c_smbus_data
* data
)
172 case I2C_SMBUS_QUICK
:
173 sis96x_write(SMB_ADDR
, ((addr
& 0x7f) << 1) | (read_write
& 0x01));
178 sis96x_write(SMB_ADDR
, ((addr
& 0x7f) << 1) | (read_write
& 0x01));
179 if (read_write
== I2C_SMBUS_WRITE
)
180 sis96x_write(SMB_CMD
, command
);
184 case I2C_SMBUS_BYTE_DATA
:
185 sis96x_write(SMB_ADDR
, ((addr
& 0x7f) << 1) | (read_write
& 0x01));
186 sis96x_write(SMB_CMD
, command
);
187 if (read_write
== I2C_SMBUS_WRITE
)
188 sis96x_write(SMB_BYTE
, data
->byte
);
189 size
= SIS96x_BYTE_DATA
;
192 case I2C_SMBUS_PROC_CALL
:
193 case I2C_SMBUS_WORD_DATA
:
194 sis96x_write(SMB_ADDR
, ((addr
& 0x7f) << 1) | (read_write
& 0x01));
195 sis96x_write(SMB_CMD
, command
);
196 if (read_write
== I2C_SMBUS_WRITE
) {
197 sis96x_write(SMB_BYTE
, data
->word
& 0xff);
198 sis96x_write(SMB_BYTE
+ 1, (data
->word
& 0xff00) >> 8);
200 size
= (size
== I2C_SMBUS_PROC_CALL
?
201 SIS96x_PROC_CALL
: SIS96x_WORD_DATA
);
204 case I2C_SMBUS_BLOCK_DATA
:
206 dev_info(&adap
->dev
, "SMBus block not implemented!\n");
211 dev_info(&adap
->dev
, "Unsupported SMBus operation\n");
215 status
= sis96x_transaction(size
);
219 if ((size
!= SIS96x_PROC_CALL
) &&
220 ((read_write
== I2C_SMBUS_WRITE
) || (size
== SIS96x_QUICK
)))
225 case SIS96x_BYTE_DATA
:
226 data
->byte
= sis96x_read(SMB_BYTE
);
229 case SIS96x_WORD_DATA
:
230 case SIS96x_PROC_CALL
:
231 data
->word
= sis96x_read(SMB_BYTE
) +
232 (sis96x_read(SMB_BYTE
+ 1) << 8);
238 static u32
sis96x_func(struct i2c_adapter
*adapter
)
240 return I2C_FUNC_SMBUS_QUICK
| I2C_FUNC_SMBUS_BYTE
|
241 I2C_FUNC_SMBUS_BYTE_DATA
| I2C_FUNC_SMBUS_WORD_DATA
|
242 I2C_FUNC_SMBUS_PROC_CALL
;
245 static const struct i2c_algorithm smbus_algorithm
= {
246 .smbus_xfer
= sis96x_access
,
247 .functionality
= sis96x_func
,
250 static struct i2c_adapter sis96x_adapter
= {
251 .owner
= THIS_MODULE
,
252 .id
= I2C_HW_SMBUS_SIS96X
,
253 .class = I2C_CLASS_HWMON
,
254 .algo
= &smbus_algorithm
,
257 static struct pci_device_id sis96x_ids
[] = {
258 { PCI_DEVICE(PCI_VENDOR_ID_SI
, PCI_DEVICE_ID_SI_SMBUS
) },
262 MODULE_DEVICE_TABLE (pci
, sis96x_ids
);
264 static int __devinit
sis96x_probe(struct pci_dev
*dev
,
265 const struct pci_device_id
*id
)
270 if (sis96x_smbus_base
) {
271 dev_err(&dev
->dev
, "Only one device supported.\n");
275 pci_read_config_word(dev
, PCI_CLASS_DEVICE
, &ww
);
276 if (PCI_CLASS_SERIAL_SMBUS
!= ww
) {
277 dev_err(&dev
->dev
, "Unsupported device class 0x%04x!\n", ww
);
281 sis96x_smbus_base
= pci_resource_start(dev
, SIS96x_BAR
);
282 if (!sis96x_smbus_base
) {
283 dev_err(&dev
->dev
, "SiS96x SMBus base address "
284 "not initialized!\n");
287 dev_info(&dev
->dev
, "SiS96x SMBus base address: 0x%04x\n",
290 /* Everything is happy, let's grab the memory and set things up. */
291 if (!request_region(sis96x_smbus_base
, SMB_IOSIZE
,
292 sis96x_driver
.name
)) {
293 dev_err(&dev
->dev
, "SMBus registers 0x%04x-0x%04x "
294 "already in use!\n", sis96x_smbus_base
,
295 sis96x_smbus_base
+ SMB_IOSIZE
- 1);
297 sis96x_smbus_base
= 0;
301 /* set up the sysfs linkage to our parent device */
302 sis96x_adapter
.dev
.parent
= &dev
->dev
;
304 snprintf(sis96x_adapter
.name
, sizeof(sis96x_adapter
.name
),
305 "SiS96x SMBus adapter at 0x%04x", sis96x_smbus_base
);
307 if ((retval
= i2c_add_adapter(&sis96x_adapter
))) {
308 dev_err(&dev
->dev
, "Couldn't register adapter!\n");
309 release_region(sis96x_smbus_base
, SMB_IOSIZE
);
310 sis96x_smbus_base
= 0;
316 static void __devexit
sis96x_remove(struct pci_dev
*dev
)
318 if (sis96x_smbus_base
) {
319 i2c_del_adapter(&sis96x_adapter
);
320 release_region(sis96x_smbus_base
, SMB_IOSIZE
);
321 sis96x_smbus_base
= 0;
325 static struct pci_driver sis96x_driver
= {
326 .name
= "sis96x_smbus",
327 .id_table
= sis96x_ids
,
328 .probe
= sis96x_probe
,
329 .remove
= __devexit_p(sis96x_remove
),
332 static int __init
i2c_sis96x_init(void)
334 return pci_register_driver(&sis96x_driver
);
337 static void __exit
i2c_sis96x_exit(void)
339 pci_unregister_driver(&sis96x_driver
);
342 MODULE_AUTHOR("Mark M. Hoffman <mhoffman@lightlink.com>");
343 MODULE_DESCRIPTION("SiS96x SMBus driver");
344 MODULE_LICENSE("GPL");
346 /* Register initialization functions using helper macros */
347 module_init(i2c_sis96x_init
);
348 module_exit(i2c_sis96x_exit
);