2 * Driver for the i2c controller on the Marvell line of host bridges for MIPS
3 * and PPC (e.g, gt642[46]0, mv643[46]0, mv644[46]0).
5 * Author: Mark A. Greer <mgreer@mvista.com>
7 * 2005 (c) MontaVista, Software, Inc. This file is licensed under
8 * the terms of the GNU General Public License version 2. This program
9 * is licensed "as is" without any warranty of any kind, whether express
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/spinlock.h>
15 #include <linux/i2c.h>
16 #include <linux/interrupt.h>
17 #include <linux/mv643xx.h>
18 #include <linux/platform_device.h>
22 /* Register defines */
23 #define MV64XXX_I2C_REG_SLAVE_ADDR 0x00
24 #define MV64XXX_I2C_REG_DATA 0x04
25 #define MV64XXX_I2C_REG_CONTROL 0x08
26 #define MV64XXX_I2C_REG_STATUS 0x0c
27 #define MV64XXX_I2C_REG_BAUD 0x0c
28 #define MV64XXX_I2C_REG_EXT_SLAVE_ADDR 0x10
29 #define MV64XXX_I2C_REG_SOFT_RESET 0x1c
31 #define MV64XXX_I2C_REG_CONTROL_ACK 0x00000004
32 #define MV64XXX_I2C_REG_CONTROL_IFLG 0x00000008
33 #define MV64XXX_I2C_REG_CONTROL_STOP 0x00000010
34 #define MV64XXX_I2C_REG_CONTROL_START 0x00000020
35 #define MV64XXX_I2C_REG_CONTROL_TWSIEN 0x00000040
36 #define MV64XXX_I2C_REG_CONTROL_INTEN 0x00000080
38 /* Ctlr status values */
39 #define MV64XXX_I2C_STATUS_BUS_ERR 0x00
40 #define MV64XXX_I2C_STATUS_MAST_START 0x08
41 #define MV64XXX_I2C_STATUS_MAST_REPEAT_START 0x10
42 #define MV64XXX_I2C_STATUS_MAST_WR_ADDR_ACK 0x18
43 #define MV64XXX_I2C_STATUS_MAST_WR_ADDR_NO_ACK 0x20
44 #define MV64XXX_I2C_STATUS_MAST_WR_ACK 0x28
45 #define MV64XXX_I2C_STATUS_MAST_WR_NO_ACK 0x30
46 #define MV64XXX_I2C_STATUS_MAST_LOST_ARB 0x38
47 #define MV64XXX_I2C_STATUS_MAST_RD_ADDR_ACK 0x40
48 #define MV64XXX_I2C_STATUS_MAST_RD_ADDR_NO_ACK 0x48
49 #define MV64XXX_I2C_STATUS_MAST_RD_DATA_ACK 0x50
50 #define MV64XXX_I2C_STATUS_MAST_RD_DATA_NO_ACK 0x58
51 #define MV64XXX_I2C_STATUS_MAST_WR_ADDR_2_ACK 0xd0
52 #define MV64XXX_I2C_STATUS_MAST_WR_ADDR_2_NO_ACK 0xd8
53 #define MV64XXX_I2C_STATUS_MAST_RD_ADDR_2_ACK 0xe0
54 #define MV64XXX_I2C_STATUS_MAST_RD_ADDR_2_NO_ACK 0xe8
55 #define MV64XXX_I2C_STATUS_NO_STATUS 0xf8
59 MV64XXX_I2C_STATE_INVALID
,
60 MV64XXX_I2C_STATE_IDLE
,
61 MV64XXX_I2C_STATE_WAITING_FOR_START_COND
,
62 MV64XXX_I2C_STATE_WAITING_FOR_ADDR_1_ACK
,
63 MV64XXX_I2C_STATE_WAITING_FOR_ADDR_2_ACK
,
64 MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_ACK
,
65 MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_DATA
,
70 MV64XXX_I2C_ACTION_INVALID
,
71 MV64XXX_I2C_ACTION_CONTINUE
,
72 MV64XXX_I2C_ACTION_SEND_START
,
73 MV64XXX_I2C_ACTION_SEND_ADDR_1
,
74 MV64XXX_I2C_ACTION_SEND_ADDR_2
,
75 MV64XXX_I2C_ACTION_SEND_DATA
,
76 MV64XXX_I2C_ACTION_RCV_DATA
,
77 MV64XXX_I2C_ACTION_RCV_DATA_STOP
,
78 MV64XXX_I2C_ACTION_SEND_STOP
,
81 struct mv64xxx_i2c_data
{
87 void __iomem
*reg_base
;
97 wait_queue_head_t waitq
;
100 struct i2c_adapter adapter
;
104 *****************************************************************************
106 * Finite State Machine & Interrupt Routines
108 *****************************************************************************
111 /* Reset hardware and initialize FSM */
113 mv64xxx_i2c_hw_init(struct mv64xxx_i2c_data
*drv_data
)
115 writel(0, drv_data
->reg_base
+ MV64XXX_I2C_REG_SOFT_RESET
);
116 writel((((drv_data
->freq_m
& 0xf) << 3) | (drv_data
->freq_n
& 0x7)),
117 drv_data
->reg_base
+ MV64XXX_I2C_REG_BAUD
);
118 writel(0, drv_data
->reg_base
+ MV64XXX_I2C_REG_SLAVE_ADDR
);
119 writel(0, drv_data
->reg_base
+ MV64XXX_I2C_REG_EXT_SLAVE_ADDR
);
120 writel(MV64XXX_I2C_REG_CONTROL_TWSIEN
| MV64XXX_I2C_REG_CONTROL_STOP
,
121 drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
);
122 drv_data
->state
= MV64XXX_I2C_STATE_IDLE
;
126 mv64xxx_i2c_fsm(struct mv64xxx_i2c_data
*drv_data
, u32 status
)
129 * If state is idle, then this is likely the remnants of an old
130 * operation that driver has given up on or the user has killed.
131 * If so, issue the stop condition and go to idle.
133 if (drv_data
->state
== MV64XXX_I2C_STATE_IDLE
) {
134 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_STOP
;
138 /* The status from the ctlr [mostly] tells us what to do next */
140 /* Start condition interrupt */
141 case MV64XXX_I2C_STATUS_MAST_START
: /* 0x08 */
142 case MV64XXX_I2C_STATUS_MAST_REPEAT_START
: /* 0x10 */
143 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_ADDR_1
;
144 drv_data
->state
= MV64XXX_I2C_STATE_WAITING_FOR_ADDR_1_ACK
;
147 /* Performing a write */
148 case MV64XXX_I2C_STATUS_MAST_WR_ADDR_ACK
: /* 0x18 */
149 if (drv_data
->msg
->flags
& I2C_M_TEN
) {
150 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_ADDR_2
;
152 MV64XXX_I2C_STATE_WAITING_FOR_ADDR_2_ACK
;
156 case MV64XXX_I2C_STATUS_MAST_WR_ADDR_2_ACK
: /* 0xd0 */
157 case MV64XXX_I2C_STATUS_MAST_WR_ACK
: /* 0x28 */
158 if ((drv_data
->bytes_left
== 0)
159 || (drv_data
->aborting
160 && (drv_data
->byte_posn
!= 0))) {
161 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_STOP
;
162 drv_data
->state
= MV64XXX_I2C_STATE_IDLE
;
164 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_DATA
;
166 MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_ACK
;
167 drv_data
->bytes_left
--;
171 /* Performing a read */
172 case MV64XXX_I2C_STATUS_MAST_RD_ADDR_ACK
: /* 40 */
173 if (drv_data
->msg
->flags
& I2C_M_TEN
) {
174 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_ADDR_2
;
176 MV64XXX_I2C_STATE_WAITING_FOR_ADDR_2_ACK
;
180 case MV64XXX_I2C_STATUS_MAST_RD_ADDR_2_ACK
: /* 0xe0 */
181 if (drv_data
->bytes_left
== 0) {
182 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_STOP
;
183 drv_data
->state
= MV64XXX_I2C_STATE_IDLE
;
187 case MV64XXX_I2C_STATUS_MAST_RD_DATA_ACK
: /* 0x50 */
188 if (status
!= MV64XXX_I2C_STATUS_MAST_RD_DATA_ACK
)
189 drv_data
->action
= MV64XXX_I2C_ACTION_CONTINUE
;
191 drv_data
->action
= MV64XXX_I2C_ACTION_RCV_DATA
;
192 drv_data
->bytes_left
--;
194 drv_data
->state
= MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_DATA
;
196 if ((drv_data
->bytes_left
== 1) || drv_data
->aborting
)
197 drv_data
->cntl_bits
&= ~MV64XXX_I2C_REG_CONTROL_ACK
;
200 case MV64XXX_I2C_STATUS_MAST_RD_DATA_NO_ACK
: /* 0x58 */
201 drv_data
->action
= MV64XXX_I2C_ACTION_RCV_DATA_STOP
;
202 drv_data
->state
= MV64XXX_I2C_STATE_IDLE
;
205 case MV64XXX_I2C_STATUS_MAST_WR_ADDR_NO_ACK
: /* 0x20 */
206 case MV64XXX_I2C_STATUS_MAST_WR_NO_ACK
: /* 30 */
207 case MV64XXX_I2C_STATUS_MAST_RD_ADDR_NO_ACK
: /* 48 */
208 /* Doesn't seem to be a device at other end */
209 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_STOP
;
210 drv_data
->state
= MV64XXX_I2C_STATE_IDLE
;
211 drv_data
->rc
= -ENODEV
;
215 dev_err(&drv_data
->adapter
.dev
,
216 "mv64xxx_i2c_fsm: Ctlr Error -- state: 0x%x, "
217 "status: 0x%x, addr: 0x%x, flags: 0x%x\n",
218 drv_data
->state
, status
, drv_data
->msg
->addr
,
219 drv_data
->msg
->flags
);
220 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_STOP
;
221 mv64xxx_i2c_hw_init(drv_data
);
227 mv64xxx_i2c_do_action(struct mv64xxx_i2c_data
*drv_data
)
229 switch(drv_data
->action
) {
230 case MV64XXX_I2C_ACTION_CONTINUE
:
231 writel(drv_data
->cntl_bits
,
232 drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
);
235 case MV64XXX_I2C_ACTION_SEND_START
:
236 writel(drv_data
->cntl_bits
| MV64XXX_I2C_REG_CONTROL_START
,
237 drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
);
240 case MV64XXX_I2C_ACTION_SEND_ADDR_1
:
241 writel(drv_data
->addr1
,
242 drv_data
->reg_base
+ MV64XXX_I2C_REG_DATA
);
243 writel(drv_data
->cntl_bits
,
244 drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
);
247 case MV64XXX_I2C_ACTION_SEND_ADDR_2
:
248 writel(drv_data
->addr2
,
249 drv_data
->reg_base
+ MV64XXX_I2C_REG_DATA
);
250 writel(drv_data
->cntl_bits
,
251 drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
);
254 case MV64XXX_I2C_ACTION_SEND_DATA
:
255 writel(drv_data
->msg
->buf
[drv_data
->byte_posn
++],
256 drv_data
->reg_base
+ MV64XXX_I2C_REG_DATA
);
257 writel(drv_data
->cntl_bits
,
258 drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
);
261 case MV64XXX_I2C_ACTION_RCV_DATA
:
262 drv_data
->msg
->buf
[drv_data
->byte_posn
++] =
263 readl(drv_data
->reg_base
+ MV64XXX_I2C_REG_DATA
);
264 writel(drv_data
->cntl_bits
,
265 drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
);
268 case MV64XXX_I2C_ACTION_RCV_DATA_STOP
:
269 drv_data
->msg
->buf
[drv_data
->byte_posn
++] =
270 readl(drv_data
->reg_base
+ MV64XXX_I2C_REG_DATA
);
271 drv_data
->cntl_bits
&= ~MV64XXX_I2C_REG_CONTROL_INTEN
;
272 writel(drv_data
->cntl_bits
| MV64XXX_I2C_REG_CONTROL_STOP
,
273 drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
);
275 wake_up_interruptible(&drv_data
->waitq
);
278 case MV64XXX_I2C_ACTION_INVALID
:
280 dev_err(&drv_data
->adapter
.dev
,
281 "mv64xxx_i2c_do_action: Invalid action: %d\n",
285 case MV64XXX_I2C_ACTION_SEND_STOP
:
286 drv_data
->cntl_bits
&= ~MV64XXX_I2C_REG_CONTROL_INTEN
;
287 writel(drv_data
->cntl_bits
| MV64XXX_I2C_REG_CONTROL_STOP
,
288 drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
);
290 wake_up_interruptible(&drv_data
->waitq
);
296 mv64xxx_i2c_intr(int irq
, void *dev_id
)
298 struct mv64xxx_i2c_data
*drv_data
= dev_id
;
303 spin_lock_irqsave(&drv_data
->lock
, flags
);
304 while (readl(drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
) &
305 MV64XXX_I2C_REG_CONTROL_IFLG
) {
306 status
= readl(drv_data
->reg_base
+ MV64XXX_I2C_REG_STATUS
);
307 mv64xxx_i2c_fsm(drv_data
, status
);
308 mv64xxx_i2c_do_action(drv_data
);
311 spin_unlock_irqrestore(&drv_data
->lock
, flags
);
317 *****************************************************************************
319 * I2C Msg Execution Routines
321 *****************************************************************************
324 mv64xxx_i2c_prepare_for_io(struct mv64xxx_i2c_data
*drv_data
,
330 drv_data
->byte_posn
= 0;
331 drv_data
->bytes_left
= msg
->len
;
332 drv_data
->aborting
= 0;
334 drv_data
->cntl_bits
= MV64XXX_I2C_REG_CONTROL_ACK
|
335 MV64XXX_I2C_REG_CONTROL_INTEN
| MV64XXX_I2C_REG_CONTROL_TWSIEN
;
337 if (msg
->flags
& I2C_M_RD
)
340 if (msg
->flags
& I2C_M_REV_DIR_ADDR
)
343 if (msg
->flags
& I2C_M_TEN
) {
344 drv_data
->addr1
= 0xf0 | (((u32
)msg
->addr
& 0x300) >> 7) | dir
;
345 drv_data
->addr2
= (u32
)msg
->addr
& 0xff;
347 drv_data
->addr1
= ((u32
)msg
->addr
& 0x7f) << 1 | dir
;
353 mv64xxx_i2c_wait_for_completion(struct mv64xxx_i2c_data
*drv_data
)
359 time_left
= wait_event_interruptible_timeout(drv_data
->waitq
,
360 !drv_data
->block
, msecs_to_jiffies(drv_data
->adapter
.timeout
));
362 spin_lock_irqsave(&drv_data
->lock
, flags
);
363 if (!time_left
) { /* Timed out */
364 drv_data
->rc
= -ETIMEDOUT
;
366 } else if (time_left
< 0) { /* Interrupted/Error */
367 drv_data
->rc
= time_left
; /* errno value */
371 if (abort
&& drv_data
->block
) {
372 drv_data
->aborting
= 1;
373 spin_unlock_irqrestore(&drv_data
->lock
, flags
);
375 time_left
= wait_event_timeout(drv_data
->waitq
,
377 msecs_to_jiffies(drv_data
->adapter
.timeout
));
379 if ((time_left
<= 0) && drv_data
->block
) {
380 drv_data
->state
= MV64XXX_I2C_STATE_IDLE
;
381 dev_err(&drv_data
->adapter
.dev
,
382 "mv64xxx: I2C bus locked, block: %d, "
383 "time_left: %d\n", drv_data
->block
,
385 mv64xxx_i2c_hw_init(drv_data
);
388 spin_unlock_irqrestore(&drv_data
->lock
, flags
);
392 mv64xxx_i2c_execute_msg(struct mv64xxx_i2c_data
*drv_data
, struct i2c_msg
*msg
)
396 spin_lock_irqsave(&drv_data
->lock
, flags
);
397 mv64xxx_i2c_prepare_for_io(drv_data
, msg
);
399 if (unlikely(msg
->flags
& I2C_M_NOSTART
)) { /* Skip start/addr phases */
400 if (drv_data
->msg
->flags
& I2C_M_RD
) {
401 /* No action to do, wait for slave to send a byte */
402 drv_data
->action
= MV64XXX_I2C_ACTION_CONTINUE
;
404 MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_DATA
;
406 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_DATA
;
408 MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_ACK
;
409 drv_data
->bytes_left
--;
412 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_START
;
413 drv_data
->state
= MV64XXX_I2C_STATE_WAITING_FOR_START_COND
;
417 mv64xxx_i2c_do_action(drv_data
);
418 spin_unlock_irqrestore(&drv_data
->lock
, flags
);
420 mv64xxx_i2c_wait_for_completion(drv_data
);
425 *****************************************************************************
427 * I2C Core Support Routines (Interface to higher level I2C code)
429 *****************************************************************************
432 mv64xxx_i2c_functionality(struct i2c_adapter
*adap
)
434 return I2C_FUNC_I2C
| I2C_FUNC_10BIT_ADDR
| I2C_FUNC_SMBUS_EMUL
;
438 mv64xxx_i2c_xfer(struct i2c_adapter
*adap
, struct i2c_msg msgs
[], int num
)
440 struct mv64xxx_i2c_data
*drv_data
= i2c_get_adapdata(adap
);
443 for (i
=0; i
<num
; i
++)
444 if ((rc
= mv64xxx_i2c_execute_msg(drv_data
, &msgs
[i
])) < 0)
450 static const struct i2c_algorithm mv64xxx_i2c_algo
= {
451 .master_xfer
= mv64xxx_i2c_xfer
,
452 .functionality
= mv64xxx_i2c_functionality
,
456 *****************************************************************************
458 * Driver Interface & Early Init Routines
460 *****************************************************************************
463 mv64xxx_i2c_map_regs(struct platform_device
*pd
,
464 struct mv64xxx_i2c_data
*drv_data
)
468 if ((r
= platform_get_resource(pd
, IORESOURCE_MEM
, 0)) &&
469 request_mem_region(r
->start
, MV64XXX_I2C_REG_BLOCK_SIZE
,
470 drv_data
->adapter
.name
)) {
472 drv_data
->reg_base
= ioremap(r
->start
,
473 MV64XXX_I2C_REG_BLOCK_SIZE
);
474 drv_data
->reg_base_p
= r
->start
;
481 static void __devexit
482 mv64xxx_i2c_unmap_regs(struct mv64xxx_i2c_data
*drv_data
)
484 if (drv_data
->reg_base
) {
485 iounmap(drv_data
->reg_base
);
486 release_mem_region(drv_data
->reg_base_p
,
487 MV64XXX_I2C_REG_BLOCK_SIZE
);
490 drv_data
->reg_base
= NULL
;
491 drv_data
->reg_base_p
= 0;
495 mv64xxx_i2c_probe(struct platform_device
*pd
)
497 struct mv64xxx_i2c_data
*drv_data
;
498 struct mv64xxx_i2c_pdata
*pdata
= pd
->dev
.platform_data
;
501 if ((pd
->id
!= 0) || !pdata
)
504 drv_data
= kzalloc(sizeof(struct mv64xxx_i2c_data
), GFP_KERNEL
);
508 if (mv64xxx_i2c_map_regs(pd
, drv_data
)) {
513 strlcpy(drv_data
->adapter
.name
, MV64XXX_I2C_CTLR_NAME
" adapter",
514 sizeof(drv_data
->adapter
.name
));
516 init_waitqueue_head(&drv_data
->waitq
);
517 spin_lock_init(&drv_data
->lock
);
519 drv_data
->freq_m
= pdata
->freq_m
;
520 drv_data
->freq_n
= pdata
->freq_n
;
521 drv_data
->irq
= platform_get_irq(pd
, 0);
522 if (drv_data
->irq
< 0) {
524 goto exit_unmap_regs
;
526 drv_data
->adapter
.dev
.parent
= &pd
->dev
;
527 drv_data
->adapter
.id
= I2C_HW_MV64XXX
;
528 drv_data
->adapter
.algo
= &mv64xxx_i2c_algo
;
529 drv_data
->adapter
.owner
= THIS_MODULE
;
530 drv_data
->adapter
.class = I2C_CLASS_HWMON
;
531 drv_data
->adapter
.timeout
= pdata
->timeout
;
532 drv_data
->adapter
.retries
= pdata
->retries
;
533 drv_data
->adapter
.nr
= pd
->id
;
534 platform_set_drvdata(pd
, drv_data
);
535 i2c_set_adapdata(&drv_data
->adapter
, drv_data
);
537 mv64xxx_i2c_hw_init(drv_data
);
539 if (request_irq(drv_data
->irq
, mv64xxx_i2c_intr
, 0,
540 MV64XXX_I2C_CTLR_NAME
, drv_data
)) {
541 dev_err(&drv_data
->adapter
.dev
,
542 "mv64xxx: Can't register intr handler irq: %d\n",
545 goto exit_unmap_regs
;
546 } else if ((rc
= i2c_add_numbered_adapter(&drv_data
->adapter
)) != 0) {
547 dev_err(&drv_data
->adapter
.dev
,
548 "mv64xxx: Can't add i2c adapter, rc: %d\n", -rc
);
555 free_irq(drv_data
->irq
, drv_data
);
557 mv64xxx_i2c_unmap_regs(drv_data
);
564 mv64xxx_i2c_remove(struct platform_device
*dev
)
566 struct mv64xxx_i2c_data
*drv_data
= platform_get_drvdata(dev
);
569 rc
= i2c_del_adapter(&drv_data
->adapter
);
570 free_irq(drv_data
->irq
, drv_data
);
571 mv64xxx_i2c_unmap_regs(drv_data
);
577 static struct platform_driver mv64xxx_i2c_driver
= {
578 .probe
= mv64xxx_i2c_probe
,
579 .remove
= mv64xxx_i2c_remove
,
581 .owner
= THIS_MODULE
,
582 .name
= MV64XXX_I2C_CTLR_NAME
,
587 mv64xxx_i2c_init(void)
589 return platform_driver_register(&mv64xxx_i2c_driver
);
593 mv64xxx_i2c_exit(void)
595 platform_driver_unregister(&mv64xxx_i2c_driver
);
598 module_init(mv64xxx_i2c_init
);
599 module_exit(mv64xxx_i2c_exit
);
601 MODULE_AUTHOR("Mark A. Greer <mgreer@mvista.com>");
602 MODULE_DESCRIPTION("Marvell mv64xxx host bridge i2c ctlr driver");
603 MODULE_LICENSE("GPL");