2 * Copyright (C) 2006-2007 PA Semi, Inc
4 * SMBus host driver for PA Semi PWRficient
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 #include <linux/module.h>
21 #include <linux/pci.h>
22 #include <linux/kernel.h>
23 #include <linux/stddef.h>
24 #include <linux/sched.h>
25 #include <linux/i2c.h>
26 #include <linux/delay.h>
29 static struct pci_driver pasemi_smb_driver
;
33 struct i2c_adapter adapter
;
38 /* Register offsets */
39 #define REG_MTXFIFO 0x00
40 #define REG_MRXFIFO 0x04
41 #define REG_SMSTA 0x14
45 #define MTXFIFO_READ 0x00000400
46 #define MTXFIFO_STOP 0x00000200
47 #define MTXFIFO_START 0x00000100
48 #define MTXFIFO_DATA_M 0x000000ff
50 #define MRXFIFO_EMPTY 0x00000100
51 #define MRXFIFO_DATA_M 0x000000ff
53 #define SMSTA_XEN 0x08000000
54 #define SMSTA_MTN 0x00200000
56 #define CTL_MRR 0x00000400
57 #define CTL_MTR 0x00000200
58 #define CTL_CLK_M 0x000000ff
60 #define CLK_100K_DIV 84
61 #define CLK_400K_DIV 21
63 static inline void reg_write(struct pasemi_smbus
*smbus
, int reg
, int val
)
65 dev_dbg(&smbus
->dev
->dev
, "smbus write reg %lx val %08x\n",
66 smbus
->base
+ reg
, val
);
67 outl(val
, smbus
->base
+ reg
);
70 static inline int reg_read(struct pasemi_smbus
*smbus
, int reg
)
73 ret
= inl(smbus
->base
+ reg
);
74 dev_dbg(&smbus
->dev
->dev
, "smbus read reg %lx val %08x\n",
75 smbus
->base
+ reg
, ret
);
79 #define TXFIFO_WR(smbus, reg) reg_write((smbus), REG_MTXFIFO, (reg))
80 #define RXFIFO_RD(smbus) reg_read((smbus), REG_MRXFIFO)
82 static void pasemi_smb_clear(struct pasemi_smbus
*smbus
)
86 status
= reg_read(smbus
, REG_SMSTA
);
87 reg_write(smbus
, REG_SMSTA
, status
);
90 static unsigned int pasemi_smb_waitready(struct pasemi_smbus
*smbus
)
95 status
= reg_read(smbus
, REG_SMSTA
);
97 while (!(status
& SMSTA_XEN
) && timeout
--) {
99 status
= reg_read(smbus
, REG_SMSTA
);
103 if (status
& SMSTA_MTN
)
107 dev_warn(&smbus
->dev
->dev
, "Timeout, status 0x%08x\n", status
);
108 reg_write(smbus
, REG_SMSTA
, status
);
113 reg_write(smbus
, REG_SMSTA
, SMSTA_XEN
);
118 static int pasemi_i2c_xfer_msg(struct i2c_adapter
*adapter
,
119 struct i2c_msg
*msg
, int stop
)
121 struct pasemi_smbus
*smbus
= adapter
->algo_data
;
125 read
= msg
->flags
& I2C_M_RD
? 1 : 0;
127 TXFIFO_WR(smbus
, MTXFIFO_START
| (msg
->addr
<< 1) | read
);
130 TXFIFO_WR(smbus
, msg
->len
| MTXFIFO_READ
|
131 (stop
? MTXFIFO_STOP
: 0));
133 err
= pasemi_smb_waitready(smbus
);
137 for (i
= 0; i
< msg
->len
; i
++) {
138 rd
= RXFIFO_RD(smbus
);
139 if (rd
& MRXFIFO_EMPTY
) {
143 msg
->buf
[i
] = rd
& MRXFIFO_DATA_M
;
146 for (i
= 0; i
< msg
->len
- 1; i
++)
147 TXFIFO_WR(smbus
, msg
->buf
[i
]);
149 TXFIFO_WR(smbus
, msg
->buf
[msg
->len
-1] |
150 (stop
? MTXFIFO_STOP
: 0));
156 reg_write(smbus
, REG_CTL
, (CTL_MTR
| CTL_MRR
|
157 (CLK_100K_DIV
& CTL_CLK_M
)));
161 static int pasemi_i2c_xfer(struct i2c_adapter
*adapter
,
162 struct i2c_msg
*msgs
, int num
)
164 struct pasemi_smbus
*smbus
= adapter
->algo_data
;
167 pasemi_smb_clear(smbus
);
171 for (i
= 0; i
< num
&& !ret
; i
++)
172 ret
= pasemi_i2c_xfer_msg(adapter
, &msgs
[i
], (i
== (num
- 1)));
174 return ret
? ret
: num
;
177 static int pasemi_smb_xfer(struct i2c_adapter
*adapter
,
178 u16 addr
, unsigned short flags
, char read_write
, u8 command
,
179 int size
, union i2c_smbus_data
*data
)
181 struct pasemi_smbus
*smbus
= adapter
->algo_data
;
186 /* All our ops take 8-bit shifted addresses */
188 read_flag
= read_write
== I2C_SMBUS_READ
;
190 pasemi_smb_clear(smbus
);
193 case I2C_SMBUS_QUICK
:
194 TXFIFO_WR(smbus
, addr
| read_flag
| MTXFIFO_START
|
198 TXFIFO_WR(smbus
, addr
| read_flag
| MTXFIFO_START
);
200 TXFIFO_WR(smbus
, 1 | MTXFIFO_STOP
| MTXFIFO_READ
);
202 TXFIFO_WR(smbus
, MTXFIFO_STOP
| command
);
204 case I2C_SMBUS_BYTE_DATA
:
205 TXFIFO_WR(smbus
, addr
| MTXFIFO_START
);
206 TXFIFO_WR(smbus
, command
);
208 TXFIFO_WR(smbus
, addr
| I2C_SMBUS_READ
| MTXFIFO_START
);
209 TXFIFO_WR(smbus
, 1 | MTXFIFO_READ
| MTXFIFO_STOP
);
211 TXFIFO_WR(smbus
, MTXFIFO_STOP
| data
->byte
);
214 case I2C_SMBUS_WORD_DATA
:
215 TXFIFO_WR(smbus
, addr
| MTXFIFO_START
);
216 TXFIFO_WR(smbus
, command
);
218 TXFIFO_WR(smbus
, addr
| I2C_SMBUS_READ
| MTXFIFO_START
);
219 TXFIFO_WR(smbus
, 2 | MTXFIFO_READ
| MTXFIFO_STOP
);
221 TXFIFO_WR(smbus
, data
->word
& MTXFIFO_DATA_M
);
222 TXFIFO_WR(smbus
, MTXFIFO_STOP
| (data
->word
>> 8));
225 case I2C_SMBUS_BLOCK_DATA
:
226 TXFIFO_WR(smbus
, addr
| MTXFIFO_START
);
227 TXFIFO_WR(smbus
, command
);
229 TXFIFO_WR(smbus
, addr
| I2C_SMBUS_READ
| MTXFIFO_START
);
230 TXFIFO_WR(smbus
, 1 | MTXFIFO_READ
);
231 rd
= RXFIFO_RD(smbus
);
232 len
= min_t(u8
, (rd
& MRXFIFO_DATA_M
),
233 I2C_SMBUS_BLOCK_MAX
);
234 TXFIFO_WR(smbus
, len
| MTXFIFO_READ
|
237 len
= min_t(u8
, data
->block
[0], I2C_SMBUS_BLOCK_MAX
);
238 TXFIFO_WR(smbus
, len
);
239 for (i
= 1; i
< len
; i
++)
240 TXFIFO_WR(smbus
, data
->block
[i
]);
241 TXFIFO_WR(smbus
, data
->block
[len
] | MTXFIFO_STOP
);
244 case I2C_SMBUS_PROC_CALL
:
245 read_write
= I2C_SMBUS_READ
;
246 TXFIFO_WR(smbus
, addr
| MTXFIFO_START
);
247 TXFIFO_WR(smbus
, command
);
248 TXFIFO_WR(smbus
, data
->word
& MTXFIFO_DATA_M
);
249 TXFIFO_WR(smbus
, (data
->word
>> 8) & MTXFIFO_DATA_M
);
250 TXFIFO_WR(smbus
, addr
| I2C_SMBUS_READ
| MTXFIFO_START
);
251 TXFIFO_WR(smbus
, 2 | MTXFIFO_STOP
| MTXFIFO_READ
);
253 case I2C_SMBUS_BLOCK_PROC_CALL
:
254 len
= min_t(u8
, data
->block
[0], I2C_SMBUS_BLOCK_MAX
- 1);
255 read_write
= I2C_SMBUS_READ
;
256 TXFIFO_WR(smbus
, addr
| MTXFIFO_START
);
257 TXFIFO_WR(smbus
, command
);
258 TXFIFO_WR(smbus
, len
);
259 for (i
= 1; i
<= len
; i
++)
260 TXFIFO_WR(smbus
, data
->block
[i
]);
261 TXFIFO_WR(smbus
, addr
| I2C_SMBUS_READ
);
262 TXFIFO_WR(smbus
, MTXFIFO_READ
| 1);
263 rd
= RXFIFO_RD(smbus
);
264 len
= min_t(u8
, (rd
& MRXFIFO_DATA_M
),
265 I2C_SMBUS_BLOCK_MAX
- len
);
266 TXFIFO_WR(smbus
, len
| MTXFIFO_READ
| MTXFIFO_STOP
);
270 dev_warn(&adapter
->dev
, "Unsupported transaction %d\n", size
);
274 err
= pasemi_smb_waitready(smbus
);
278 if (read_write
== I2C_SMBUS_WRITE
)
283 case I2C_SMBUS_BYTE_DATA
:
284 rd
= RXFIFO_RD(smbus
);
285 if (rd
& MRXFIFO_EMPTY
) {
289 data
->byte
= rd
& MRXFIFO_DATA_M
;
291 case I2C_SMBUS_WORD_DATA
:
292 case I2C_SMBUS_PROC_CALL
:
293 rd
= RXFIFO_RD(smbus
);
294 if (rd
& MRXFIFO_EMPTY
) {
298 data
->word
= rd
& MRXFIFO_DATA_M
;
299 rd
= RXFIFO_RD(smbus
);
300 if (rd
& MRXFIFO_EMPTY
) {
304 data
->word
|= (rd
& MRXFIFO_DATA_M
) << 8;
306 case I2C_SMBUS_BLOCK_DATA
:
307 case I2C_SMBUS_BLOCK_PROC_CALL
:
308 data
->block
[0] = len
;
309 for (i
= 1; i
<= len
; i
++) {
310 rd
= RXFIFO_RD(smbus
);
311 if (rd
& MRXFIFO_EMPTY
) {
315 data
->block
[i
] = rd
& MRXFIFO_DATA_M
;
323 reg_write(smbus
, REG_CTL
, (CTL_MTR
| CTL_MRR
|
324 (CLK_100K_DIV
& CTL_CLK_M
)));
328 static u32
pasemi_smb_func(struct i2c_adapter
*adapter
)
330 return I2C_FUNC_SMBUS_QUICK
| I2C_FUNC_SMBUS_BYTE
|
331 I2C_FUNC_SMBUS_BYTE_DATA
| I2C_FUNC_SMBUS_WORD_DATA
|
332 I2C_FUNC_SMBUS_BLOCK_DATA
| I2C_FUNC_SMBUS_PROC_CALL
|
333 I2C_FUNC_SMBUS_BLOCK_PROC_CALL
| I2C_FUNC_I2C
;
336 static const struct i2c_algorithm smbus_algorithm
= {
337 .master_xfer
= pasemi_i2c_xfer
,
338 .smbus_xfer
= pasemi_smb_xfer
,
339 .functionality
= pasemi_smb_func
,
342 static int __devinit
pasemi_smb_probe(struct pci_dev
*dev
,
343 const struct pci_device_id
*id
)
345 struct pasemi_smbus
*smbus
;
348 if (!(pci_resource_flags(dev
, 0) & IORESOURCE_IO
))
351 smbus
= kzalloc(sizeof(struct pasemi_smbus
), GFP_KERNEL
);
356 smbus
->base
= pci_resource_start(dev
, 0);
357 smbus
->size
= pci_resource_len(dev
, 0);
359 if (!request_region(smbus
->base
, smbus
->size
,
360 pasemi_smb_driver
.name
)) {
365 smbus
->adapter
.owner
= THIS_MODULE
;
366 snprintf(smbus
->adapter
.name
, sizeof(smbus
->adapter
.name
),
367 "PA Semi SMBus adapter at 0x%lx", smbus
->base
);
368 smbus
->adapter
.class = I2C_CLASS_HWMON
;
369 smbus
->adapter
.algo
= &smbus_algorithm
;
370 smbus
->adapter
.algo_data
= smbus
;
371 smbus
->adapter
.nr
= PCI_FUNC(dev
->devfn
);
373 /* set up the sysfs linkage to our parent device */
374 smbus
->adapter
.dev
.parent
= &dev
->dev
;
376 reg_write(smbus
, REG_CTL
, (CTL_MTR
| CTL_MRR
|
377 (CLK_100K_DIV
& CTL_CLK_M
)));
379 error
= i2c_add_numbered_adapter(&smbus
->adapter
);
381 goto out_release_region
;
383 pci_set_drvdata(dev
, smbus
);
388 release_region(smbus
->base
, smbus
->size
);
394 static void __devexit
pasemi_smb_remove(struct pci_dev
*dev
)
396 struct pasemi_smbus
*smbus
= pci_get_drvdata(dev
);
398 i2c_del_adapter(&smbus
->adapter
);
399 release_region(smbus
->base
, smbus
->size
);
403 static struct pci_device_id pasemi_smb_ids
[] = {
404 { PCI_DEVICE(0x1959, 0xa003) },
408 MODULE_DEVICE_TABLE(pci
, pasemi_smb_ids
);
410 static struct pci_driver pasemi_smb_driver
= {
411 .name
= "i2c-pasemi",
412 .id_table
= pasemi_smb_ids
,
413 .probe
= pasemi_smb_probe
,
414 .remove
= __devexit_p(pasemi_smb_remove
),
417 static int __init
pasemi_smb_init(void)
419 return pci_register_driver(&pasemi_smb_driver
);
422 static void __exit
pasemi_smb_exit(void)
424 pci_unregister_driver(&pasemi_smb_driver
);
427 MODULE_LICENSE("GPL");
428 MODULE_AUTHOR ("Olof Johansson <olof@lixom.net>");
429 MODULE_DESCRIPTION("PA Semi PWRficient SMBus driver");
431 module_init(pasemi_smb_init
);
432 module_exit(pasemi_smb_exit
);