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
55 #define CTL_MRR 0x00000400
56 #define CTL_MTR 0x00000200
57 #define CTL_CLK_M 0x000000ff
59 #define CLK_100K_DIV 84
60 #define CLK_400K_DIV 21
62 static inline void reg_write(struct pasemi_smbus
*smbus
, int reg
, int val
)
64 dev_dbg(&smbus
->dev
->dev
, "smbus write reg %lx val %08x\n",
65 smbus
->base
+ reg
, val
);
66 outl(val
, smbus
->base
+ reg
);
69 static inline int reg_read(struct pasemi_smbus
*smbus
, int reg
)
72 ret
= inl(smbus
->base
+ reg
);
73 dev_dbg(&smbus
->dev
->dev
, "smbus read reg %lx val %08x\n",
74 smbus
->base
+ reg
, ret
);
78 #define TXFIFO_WR(smbus, reg) reg_write((smbus), REG_MTXFIFO, (reg))
79 #define RXFIFO_RD(smbus) reg_read((smbus), REG_MRXFIFO)
81 static void pasemi_smb_clear(struct pasemi_smbus
*smbus
)
85 status
= reg_read(smbus
, REG_SMSTA
);
86 reg_write(smbus
, REG_SMSTA
, status
);
89 static unsigned int pasemi_smb_waitready(struct pasemi_smbus
*smbus
)
94 status
= reg_read(smbus
, REG_SMSTA
);
96 while (!(status
& SMSTA_XEN
) && timeout
--) {
98 status
= reg_read(smbus
, REG_SMSTA
);
102 dev_warn(&smbus
->dev
->dev
, "Timeout, status 0x%08x\n", status
);
103 reg_write(smbus
, REG_SMSTA
, status
);
108 reg_write(smbus
, REG_SMSTA
, SMSTA_XEN
);
113 static int pasemi_i2c_xfer_msg(struct i2c_adapter
*adapter
,
114 struct i2c_msg
*msg
, int stop
)
116 struct pasemi_smbus
*smbus
= adapter
->algo_data
;
120 read
= msg
->flags
& I2C_M_RD
? 1 : 0;
122 TXFIFO_WR(smbus
, MTXFIFO_START
| (msg
->addr
<< 1) | read
);
125 TXFIFO_WR(smbus
, msg
->len
| MTXFIFO_READ
|
126 (stop
? MTXFIFO_STOP
: 0));
128 err
= pasemi_smb_waitready(smbus
);
132 for (i
= 0; i
< msg
->len
; i
++) {
133 rd
= RXFIFO_RD(smbus
);
134 if (rd
& MRXFIFO_EMPTY
) {
138 msg
->buf
[i
] = rd
& MRXFIFO_DATA_M
;
141 for (i
= 0; i
< msg
->len
- 1; i
++)
142 TXFIFO_WR(smbus
, msg
->buf
[i
]);
144 TXFIFO_WR(smbus
, msg
->buf
[msg
->len
-1] |
145 (stop
? MTXFIFO_STOP
: 0));
151 reg_write(smbus
, REG_CTL
, (CTL_MTR
| CTL_MRR
|
152 (CLK_100K_DIV
& CTL_CLK_M
)));
156 static int pasemi_i2c_xfer(struct i2c_adapter
*adapter
,
157 struct i2c_msg
*msgs
, int num
)
159 struct pasemi_smbus
*smbus
= adapter
->algo_data
;
162 pasemi_smb_clear(smbus
);
166 for (i
= 0; i
< num
&& !ret
; i
++)
167 ret
= pasemi_i2c_xfer_msg(adapter
, &msgs
[i
], (i
== (num
- 1)));
169 return ret
? ret
: num
;
172 static int pasemi_smb_xfer(struct i2c_adapter
*adapter
,
173 u16 addr
, unsigned short flags
, char read_write
, u8 command
,
174 int size
, union i2c_smbus_data
*data
)
176 struct pasemi_smbus
*smbus
= adapter
->algo_data
;
181 /* All our ops take 8-bit shifted addresses */
183 read_flag
= read_write
== I2C_SMBUS_READ
;
185 pasemi_smb_clear(smbus
);
188 case I2C_SMBUS_QUICK
:
189 TXFIFO_WR(smbus
, addr
| read_flag
| MTXFIFO_START
|
193 TXFIFO_WR(smbus
, addr
| read_flag
| MTXFIFO_START
);
195 TXFIFO_WR(smbus
, 1 | MTXFIFO_STOP
| MTXFIFO_READ
);
197 TXFIFO_WR(smbus
, MTXFIFO_STOP
| command
);
199 case I2C_SMBUS_BYTE_DATA
:
200 TXFIFO_WR(smbus
, addr
| MTXFIFO_START
);
201 TXFIFO_WR(smbus
, command
);
203 TXFIFO_WR(smbus
, addr
| I2C_SMBUS_READ
| MTXFIFO_START
);
204 TXFIFO_WR(smbus
, 1 | MTXFIFO_READ
| MTXFIFO_STOP
);
206 TXFIFO_WR(smbus
, MTXFIFO_STOP
| data
->byte
);
209 case I2C_SMBUS_WORD_DATA
:
210 TXFIFO_WR(smbus
, addr
| MTXFIFO_START
);
211 TXFIFO_WR(smbus
, command
);
213 TXFIFO_WR(smbus
, addr
| I2C_SMBUS_READ
| MTXFIFO_START
);
214 TXFIFO_WR(smbus
, 2 | MTXFIFO_READ
| MTXFIFO_STOP
);
216 TXFIFO_WR(smbus
, data
->word
& MTXFIFO_DATA_M
);
217 TXFIFO_WR(smbus
, MTXFIFO_STOP
| (data
->word
>> 8));
220 case I2C_SMBUS_BLOCK_DATA
:
221 TXFIFO_WR(smbus
, addr
| MTXFIFO_START
);
222 TXFIFO_WR(smbus
, command
);
224 TXFIFO_WR(smbus
, addr
| I2C_SMBUS_READ
| MTXFIFO_START
);
225 TXFIFO_WR(smbus
, 1 | MTXFIFO_READ
);
226 rd
= RXFIFO_RD(smbus
);
227 len
= min_t(u8
, (rd
& MRXFIFO_DATA_M
),
228 I2C_SMBUS_BLOCK_MAX
);
229 TXFIFO_WR(smbus
, len
| MTXFIFO_READ
|
232 len
= min_t(u8
, data
->block
[0], I2C_SMBUS_BLOCK_MAX
);
233 TXFIFO_WR(smbus
, len
);
234 for (i
= 1; i
< len
; i
++)
235 TXFIFO_WR(smbus
, data
->block
[i
]);
236 TXFIFO_WR(smbus
, data
->block
[len
] | MTXFIFO_STOP
);
239 case I2C_SMBUS_PROC_CALL
:
240 read_write
= I2C_SMBUS_READ
;
241 TXFIFO_WR(smbus
, addr
| MTXFIFO_START
);
242 TXFIFO_WR(smbus
, command
);
243 TXFIFO_WR(smbus
, data
->word
& MTXFIFO_DATA_M
);
244 TXFIFO_WR(smbus
, (data
->word
>> 8) & MTXFIFO_DATA_M
);
245 TXFIFO_WR(smbus
, addr
| I2C_SMBUS_READ
| MTXFIFO_START
);
246 TXFIFO_WR(smbus
, 2 | MTXFIFO_STOP
| MTXFIFO_READ
);
248 case I2C_SMBUS_BLOCK_PROC_CALL
:
249 len
= min_t(u8
, data
->block
[0], I2C_SMBUS_BLOCK_MAX
- 1);
250 read_write
= I2C_SMBUS_READ
;
251 TXFIFO_WR(smbus
, addr
| MTXFIFO_START
);
252 TXFIFO_WR(smbus
, command
);
253 TXFIFO_WR(smbus
, len
);
254 for (i
= 1; i
<= len
; i
++)
255 TXFIFO_WR(smbus
, data
->block
[i
]);
256 TXFIFO_WR(smbus
, addr
| I2C_SMBUS_READ
);
257 TXFIFO_WR(smbus
, MTXFIFO_READ
| 1);
258 rd
= RXFIFO_RD(smbus
);
259 len
= min_t(u8
, (rd
& MRXFIFO_DATA_M
),
260 I2C_SMBUS_BLOCK_MAX
- len
);
261 TXFIFO_WR(smbus
, len
| MTXFIFO_READ
| MTXFIFO_STOP
);
265 dev_warn(&adapter
->dev
, "Unsupported transaction %d\n", size
);
269 err
= pasemi_smb_waitready(smbus
);
273 if (read_write
== I2C_SMBUS_WRITE
)
278 case I2C_SMBUS_BYTE_DATA
:
279 rd
= RXFIFO_RD(smbus
);
280 if (rd
& MRXFIFO_EMPTY
) {
284 data
->byte
= rd
& MRXFIFO_DATA_M
;
286 case I2C_SMBUS_WORD_DATA
:
287 case I2C_SMBUS_PROC_CALL
:
288 rd
= RXFIFO_RD(smbus
);
289 if (rd
& MRXFIFO_EMPTY
) {
293 data
->word
= rd
& MRXFIFO_DATA_M
;
294 rd
= RXFIFO_RD(smbus
);
295 if (rd
& MRXFIFO_EMPTY
) {
299 data
->word
|= (rd
& MRXFIFO_DATA_M
) << 8;
301 case I2C_SMBUS_BLOCK_DATA
:
302 case I2C_SMBUS_BLOCK_PROC_CALL
:
303 data
->block
[0] = len
;
304 for (i
= 1; i
<= len
; i
++) {
305 rd
= RXFIFO_RD(smbus
);
306 if (rd
& MRXFIFO_EMPTY
) {
310 data
->block
[i
] = rd
& MRXFIFO_DATA_M
;
318 reg_write(smbus
, REG_CTL
, (CTL_MTR
| CTL_MRR
|
319 (CLK_100K_DIV
& CTL_CLK_M
)));
323 static u32
pasemi_smb_func(struct i2c_adapter
*adapter
)
325 return I2C_FUNC_SMBUS_QUICK
| I2C_FUNC_SMBUS_BYTE
|
326 I2C_FUNC_SMBUS_BYTE_DATA
| I2C_FUNC_SMBUS_WORD_DATA
|
327 I2C_FUNC_SMBUS_BLOCK_DATA
| I2C_FUNC_SMBUS_PROC_CALL
|
328 I2C_FUNC_SMBUS_BLOCK_PROC_CALL
| I2C_FUNC_I2C
;
331 static const struct i2c_algorithm smbus_algorithm
= {
332 .master_xfer
= pasemi_i2c_xfer
,
333 .smbus_xfer
= pasemi_smb_xfer
,
334 .functionality
= pasemi_smb_func
,
337 static int __devinit
pasemi_smb_probe(struct pci_dev
*dev
,
338 const struct pci_device_id
*id
)
340 struct pasemi_smbus
*smbus
;
343 if (!(pci_resource_flags(dev
, 0) & IORESOURCE_IO
))
346 smbus
= kzalloc(sizeof(struct pasemi_smbus
), GFP_KERNEL
);
351 smbus
->base
= pci_resource_start(dev
, 0);
352 smbus
->size
= pci_resource_len(dev
, 0);
354 if (!request_region(smbus
->base
, smbus
->size
,
355 pasemi_smb_driver
.name
)) {
360 smbus
->adapter
.owner
= THIS_MODULE
;
361 snprintf(smbus
->adapter
.name
, sizeof(smbus
->adapter
.name
),
362 "PA Semi SMBus adapter at 0x%lx", smbus
->base
);
363 smbus
->adapter
.class = I2C_CLASS_HWMON
;
364 smbus
->adapter
.algo
= &smbus_algorithm
;
365 smbus
->adapter
.algo_data
= smbus
;
367 /* set up the driverfs linkage to our parent device */
368 smbus
->adapter
.dev
.parent
= &dev
->dev
;
370 reg_write(smbus
, REG_CTL
, (CTL_MTR
| CTL_MRR
|
371 (CLK_100K_DIV
& CTL_CLK_M
)));
373 error
= i2c_add_adapter(&smbus
->adapter
);
375 goto out_release_region
;
377 pci_set_drvdata(dev
, smbus
);
382 release_region(smbus
->base
, smbus
->size
);
388 static void __devexit
pasemi_smb_remove(struct pci_dev
*dev
)
390 struct pasemi_smbus
*smbus
= pci_get_drvdata(dev
);
392 i2c_del_adapter(&smbus
->adapter
);
393 release_region(smbus
->base
, smbus
->size
);
397 static struct pci_device_id pasemi_smb_ids
[] = {
398 { PCI_DEVICE(0x1959, 0xa003) },
402 MODULE_DEVICE_TABLE(pci
, pasemi_smb_ids
);
404 static struct pci_driver pasemi_smb_driver
= {
405 .name
= "i2c-pasemi",
406 .id_table
= pasemi_smb_ids
,
407 .probe
= pasemi_smb_probe
,
408 .remove
= __devexit_p(pasemi_smb_remove
),
411 static int __init
pasemi_smb_init(void)
413 return pci_register_driver(&pasemi_smb_driver
);
416 static void __exit
pasemi_smb_exit(void)
418 pci_unregister_driver(&pasemi_smb_driver
);
421 MODULE_LICENSE("GPL");
422 MODULE_AUTHOR ("Olof Johansson <olof@lixom.net>");
423 MODULE_DESCRIPTION("PA Semi PWRficient SMBus driver");
425 module_init(pasemi_smb_init
);
426 module_exit(pasemi_smb_exit
);