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>
27 #include <linux/slab.h>
30 static struct pci_driver pasemi_smb_driver
;
34 struct i2c_adapter adapter
;
39 /* Register offsets */
40 #define REG_MTXFIFO 0x00
41 #define REG_MRXFIFO 0x04
42 #define REG_SMSTA 0x14
46 #define MTXFIFO_READ 0x00000400
47 #define MTXFIFO_STOP 0x00000200
48 #define MTXFIFO_START 0x00000100
49 #define MTXFIFO_DATA_M 0x000000ff
51 #define MRXFIFO_EMPTY 0x00000100
52 #define MRXFIFO_DATA_M 0x000000ff
54 #define SMSTA_XEN 0x08000000
55 #define SMSTA_MTN 0x00200000
57 #define CTL_MRR 0x00000400
58 #define CTL_MTR 0x00000200
59 #define CTL_CLK_M 0x000000ff
61 #define CLK_100K_DIV 84
62 #define CLK_400K_DIV 21
64 static inline void reg_write(struct pasemi_smbus
*smbus
, int reg
, int val
)
66 dev_dbg(&smbus
->dev
->dev
, "smbus write reg %lx val %08x\n",
67 smbus
->base
+ reg
, val
);
68 outl(val
, smbus
->base
+ reg
);
71 static inline int reg_read(struct pasemi_smbus
*smbus
, int reg
)
74 ret
= inl(smbus
->base
+ reg
);
75 dev_dbg(&smbus
->dev
->dev
, "smbus read reg %lx val %08x\n",
76 smbus
->base
+ reg
, ret
);
80 #define TXFIFO_WR(smbus, reg) reg_write((smbus), REG_MTXFIFO, (reg))
81 #define RXFIFO_RD(smbus) reg_read((smbus), REG_MRXFIFO)
83 static void pasemi_smb_clear(struct pasemi_smbus
*smbus
)
87 status
= reg_read(smbus
, REG_SMSTA
);
88 reg_write(smbus
, REG_SMSTA
, status
);
91 static int pasemi_smb_waitready(struct pasemi_smbus
*smbus
)
96 status
= reg_read(smbus
, REG_SMSTA
);
98 while (!(status
& SMSTA_XEN
) && timeout
--) {
100 status
= reg_read(smbus
, REG_SMSTA
);
104 if (status
& SMSTA_MTN
)
108 dev_warn(&smbus
->dev
->dev
, "Timeout, status 0x%08x\n", status
);
109 reg_write(smbus
, REG_SMSTA
, status
);
114 reg_write(smbus
, REG_SMSTA
, SMSTA_XEN
);
119 static int pasemi_i2c_xfer_msg(struct i2c_adapter
*adapter
,
120 struct i2c_msg
*msg
, int stop
)
122 struct pasemi_smbus
*smbus
= adapter
->algo_data
;
126 read
= msg
->flags
& I2C_M_RD
? 1 : 0;
128 TXFIFO_WR(smbus
, MTXFIFO_START
| (msg
->addr
<< 1) | read
);
131 TXFIFO_WR(smbus
, msg
->len
| MTXFIFO_READ
|
132 (stop
? MTXFIFO_STOP
: 0));
134 err
= pasemi_smb_waitready(smbus
);
138 for (i
= 0; i
< msg
->len
; i
++) {
139 rd
= RXFIFO_RD(smbus
);
140 if (rd
& MRXFIFO_EMPTY
) {
144 msg
->buf
[i
] = rd
& MRXFIFO_DATA_M
;
147 for (i
= 0; i
< msg
->len
- 1; i
++)
148 TXFIFO_WR(smbus
, msg
->buf
[i
]);
150 TXFIFO_WR(smbus
, msg
->buf
[msg
->len
-1] |
151 (stop
? MTXFIFO_STOP
: 0));
157 reg_write(smbus
, REG_CTL
, (CTL_MTR
| CTL_MRR
|
158 (CLK_100K_DIV
& CTL_CLK_M
)));
162 static int pasemi_i2c_xfer(struct i2c_adapter
*adapter
,
163 struct i2c_msg
*msgs
, int num
)
165 struct pasemi_smbus
*smbus
= adapter
->algo_data
;
168 pasemi_smb_clear(smbus
);
172 for (i
= 0; i
< num
&& !ret
; i
++)
173 ret
= pasemi_i2c_xfer_msg(adapter
, &msgs
[i
], (i
== (num
- 1)));
175 return ret
? ret
: num
;
178 static int pasemi_smb_xfer(struct i2c_adapter
*adapter
,
179 u16 addr
, unsigned short flags
, char read_write
, u8 command
,
180 int size
, union i2c_smbus_data
*data
)
182 struct pasemi_smbus
*smbus
= adapter
->algo_data
;
187 /* All our ops take 8-bit shifted addresses */
189 read_flag
= read_write
== I2C_SMBUS_READ
;
191 pasemi_smb_clear(smbus
);
194 case I2C_SMBUS_QUICK
:
195 TXFIFO_WR(smbus
, addr
| read_flag
| MTXFIFO_START
|
199 TXFIFO_WR(smbus
, addr
| read_flag
| MTXFIFO_START
);
201 TXFIFO_WR(smbus
, 1 | MTXFIFO_STOP
| MTXFIFO_READ
);
203 TXFIFO_WR(smbus
, MTXFIFO_STOP
| command
);
205 case I2C_SMBUS_BYTE_DATA
:
206 TXFIFO_WR(smbus
, addr
| MTXFIFO_START
);
207 TXFIFO_WR(smbus
, command
);
209 TXFIFO_WR(smbus
, addr
| I2C_SMBUS_READ
| MTXFIFO_START
);
210 TXFIFO_WR(smbus
, 1 | MTXFIFO_READ
| MTXFIFO_STOP
);
212 TXFIFO_WR(smbus
, MTXFIFO_STOP
| data
->byte
);
215 case I2C_SMBUS_WORD_DATA
:
216 TXFIFO_WR(smbus
, addr
| MTXFIFO_START
);
217 TXFIFO_WR(smbus
, command
);
219 TXFIFO_WR(smbus
, addr
| I2C_SMBUS_READ
| MTXFIFO_START
);
220 TXFIFO_WR(smbus
, 2 | MTXFIFO_READ
| MTXFIFO_STOP
);
222 TXFIFO_WR(smbus
, data
->word
& MTXFIFO_DATA_M
);
223 TXFIFO_WR(smbus
, MTXFIFO_STOP
| (data
->word
>> 8));
226 case I2C_SMBUS_BLOCK_DATA
:
227 TXFIFO_WR(smbus
, addr
| MTXFIFO_START
);
228 TXFIFO_WR(smbus
, command
);
230 TXFIFO_WR(smbus
, addr
| I2C_SMBUS_READ
| MTXFIFO_START
);
231 TXFIFO_WR(smbus
, 1 | MTXFIFO_READ
);
232 rd
= RXFIFO_RD(smbus
);
233 len
= min_t(u8
, (rd
& MRXFIFO_DATA_M
),
234 I2C_SMBUS_BLOCK_MAX
);
235 TXFIFO_WR(smbus
, len
| MTXFIFO_READ
|
238 len
= min_t(u8
, data
->block
[0], I2C_SMBUS_BLOCK_MAX
);
239 TXFIFO_WR(smbus
, len
);
240 for (i
= 1; i
< len
; i
++)
241 TXFIFO_WR(smbus
, data
->block
[i
]);
242 TXFIFO_WR(smbus
, data
->block
[len
] | MTXFIFO_STOP
);
245 case I2C_SMBUS_PROC_CALL
:
246 read_write
= I2C_SMBUS_READ
;
247 TXFIFO_WR(smbus
, addr
| MTXFIFO_START
);
248 TXFIFO_WR(smbus
, command
);
249 TXFIFO_WR(smbus
, data
->word
& MTXFIFO_DATA_M
);
250 TXFIFO_WR(smbus
, (data
->word
>> 8) & MTXFIFO_DATA_M
);
251 TXFIFO_WR(smbus
, addr
| I2C_SMBUS_READ
| MTXFIFO_START
);
252 TXFIFO_WR(smbus
, 2 | MTXFIFO_STOP
| MTXFIFO_READ
);
254 case I2C_SMBUS_BLOCK_PROC_CALL
:
255 len
= min_t(u8
, data
->block
[0], I2C_SMBUS_BLOCK_MAX
- 1);
256 read_write
= I2C_SMBUS_READ
;
257 TXFIFO_WR(smbus
, addr
| MTXFIFO_START
);
258 TXFIFO_WR(smbus
, command
);
259 TXFIFO_WR(smbus
, len
);
260 for (i
= 1; i
<= len
; i
++)
261 TXFIFO_WR(smbus
, data
->block
[i
]);
262 TXFIFO_WR(smbus
, addr
| I2C_SMBUS_READ
);
263 TXFIFO_WR(smbus
, MTXFIFO_READ
| 1);
264 rd
= RXFIFO_RD(smbus
);
265 len
= min_t(u8
, (rd
& MRXFIFO_DATA_M
),
266 I2C_SMBUS_BLOCK_MAX
- len
);
267 TXFIFO_WR(smbus
, len
| MTXFIFO_READ
| MTXFIFO_STOP
);
271 dev_warn(&adapter
->dev
, "Unsupported transaction %d\n", size
);
275 err
= pasemi_smb_waitready(smbus
);
279 if (read_write
== I2C_SMBUS_WRITE
)
284 case I2C_SMBUS_BYTE_DATA
:
285 rd
= RXFIFO_RD(smbus
);
286 if (rd
& MRXFIFO_EMPTY
) {
290 data
->byte
= rd
& MRXFIFO_DATA_M
;
292 case I2C_SMBUS_WORD_DATA
:
293 case I2C_SMBUS_PROC_CALL
:
294 rd
= RXFIFO_RD(smbus
);
295 if (rd
& MRXFIFO_EMPTY
) {
299 data
->word
= rd
& MRXFIFO_DATA_M
;
300 rd
= RXFIFO_RD(smbus
);
301 if (rd
& MRXFIFO_EMPTY
) {
305 data
->word
|= (rd
& MRXFIFO_DATA_M
) << 8;
307 case I2C_SMBUS_BLOCK_DATA
:
308 case I2C_SMBUS_BLOCK_PROC_CALL
:
309 data
->block
[0] = len
;
310 for (i
= 1; i
<= len
; i
++) {
311 rd
= RXFIFO_RD(smbus
);
312 if (rd
& MRXFIFO_EMPTY
) {
316 data
->block
[i
] = rd
& MRXFIFO_DATA_M
;
324 reg_write(smbus
, REG_CTL
, (CTL_MTR
| CTL_MRR
|
325 (CLK_100K_DIV
& CTL_CLK_M
)));
329 static u32
pasemi_smb_func(struct i2c_adapter
*adapter
)
331 return I2C_FUNC_SMBUS_QUICK
| I2C_FUNC_SMBUS_BYTE
|
332 I2C_FUNC_SMBUS_BYTE_DATA
| I2C_FUNC_SMBUS_WORD_DATA
|
333 I2C_FUNC_SMBUS_BLOCK_DATA
| I2C_FUNC_SMBUS_PROC_CALL
|
334 I2C_FUNC_SMBUS_BLOCK_PROC_CALL
| I2C_FUNC_I2C
;
337 static const struct i2c_algorithm smbus_algorithm
= {
338 .master_xfer
= pasemi_i2c_xfer
,
339 .smbus_xfer
= pasemi_smb_xfer
,
340 .functionality
= pasemi_smb_func
,
343 static int pasemi_smb_probe(struct pci_dev
*dev
,
344 const struct pci_device_id
*id
)
346 struct pasemi_smbus
*smbus
;
349 if (!(pci_resource_flags(dev
, 0) & IORESOURCE_IO
))
352 smbus
= kzalloc(sizeof(struct pasemi_smbus
), GFP_KERNEL
);
357 smbus
->base
= pci_resource_start(dev
, 0);
358 smbus
->size
= pci_resource_len(dev
, 0);
360 if (!request_region(smbus
->base
, smbus
->size
,
361 pasemi_smb_driver
.name
)) {
366 smbus
->adapter
.owner
= THIS_MODULE
;
367 snprintf(smbus
->adapter
.name
, sizeof(smbus
->adapter
.name
),
368 "PA Semi SMBus adapter at 0x%lx", smbus
->base
);
369 smbus
->adapter
.class = I2C_CLASS_HWMON
| I2C_CLASS_SPD
;
370 smbus
->adapter
.algo
= &smbus_algorithm
;
371 smbus
->adapter
.algo_data
= smbus
;
372 smbus
->adapter
.nr
= PCI_FUNC(dev
->devfn
);
374 /* set up the sysfs linkage to our parent device */
375 smbus
->adapter
.dev
.parent
= &dev
->dev
;
377 reg_write(smbus
, REG_CTL
, (CTL_MTR
| CTL_MRR
|
378 (CLK_100K_DIV
& CTL_CLK_M
)));
380 error
= i2c_add_numbered_adapter(&smbus
->adapter
);
382 goto out_release_region
;
384 pci_set_drvdata(dev
, smbus
);
389 release_region(smbus
->base
, smbus
->size
);
395 static void pasemi_smb_remove(struct pci_dev
*dev
)
397 struct pasemi_smbus
*smbus
= pci_get_drvdata(dev
);
399 i2c_del_adapter(&smbus
->adapter
);
400 release_region(smbus
->base
, smbus
->size
);
404 static DEFINE_PCI_DEVICE_TABLE(pasemi_smb_ids
) = {
405 { PCI_DEVICE(0x1959, 0xa003) },
409 MODULE_DEVICE_TABLE(pci
, pasemi_smb_ids
);
411 static struct pci_driver pasemi_smb_driver
= {
412 .name
= "i2c-pasemi",
413 .id_table
= pasemi_smb_ids
,
414 .probe
= pasemi_smb_probe
,
415 .remove
= pasemi_smb_remove
,
418 module_pci_driver(pasemi_smb_driver
);
420 MODULE_LICENSE("GPL");
421 MODULE_AUTHOR ("Olof Johansson <olof@lixom.net>");
422 MODULE_DESCRIPTION("PA Semi PWRficient SMBus driver");