2 * Driver for the i2c controller on the Marvell line of host bridges
3 * (e.g, gt642[46]0, mv643[46]0, mv644[46]0, and Orion SoC family).
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_i2c.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
;
98 wait_queue_head_t waitq
;
101 struct i2c_adapter adapter
;
105 *****************************************************************************
107 * Finite State Machine & Interrupt Routines
109 *****************************************************************************
112 /* Reset hardware and initialize FSM */
114 mv64xxx_i2c_hw_init(struct mv64xxx_i2c_data
*drv_data
)
116 writel(0, drv_data
->reg_base
+ MV64XXX_I2C_REG_SOFT_RESET
);
117 writel((((drv_data
->freq_m
& 0xf) << 3) | (drv_data
->freq_n
& 0x7)),
118 drv_data
->reg_base
+ MV64XXX_I2C_REG_BAUD
);
119 writel(0, drv_data
->reg_base
+ MV64XXX_I2C_REG_SLAVE_ADDR
);
120 writel(0, drv_data
->reg_base
+ MV64XXX_I2C_REG_EXT_SLAVE_ADDR
);
121 writel(MV64XXX_I2C_REG_CONTROL_TWSIEN
| MV64XXX_I2C_REG_CONTROL_STOP
,
122 drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
);
123 drv_data
->state
= MV64XXX_I2C_STATE_IDLE
;
127 mv64xxx_i2c_fsm(struct mv64xxx_i2c_data
*drv_data
, u32 status
)
130 * If state is idle, then this is likely the remnants of an old
131 * operation that driver has given up on or the user has killed.
132 * If so, issue the stop condition and go to idle.
134 if (drv_data
->state
== MV64XXX_I2C_STATE_IDLE
) {
135 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_STOP
;
139 /* The status from the ctlr [mostly] tells us what to do next */
141 /* Start condition interrupt */
142 case MV64XXX_I2C_STATUS_MAST_START
: /* 0x08 */
143 case MV64XXX_I2C_STATUS_MAST_REPEAT_START
: /* 0x10 */
144 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_ADDR_1
;
145 drv_data
->state
= MV64XXX_I2C_STATE_WAITING_FOR_ADDR_1_ACK
;
148 /* Performing a write */
149 case MV64XXX_I2C_STATUS_MAST_WR_ADDR_ACK
: /* 0x18 */
150 if (drv_data
->msg
->flags
& I2C_M_TEN
) {
151 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_ADDR_2
;
153 MV64XXX_I2C_STATE_WAITING_FOR_ADDR_2_ACK
;
157 case MV64XXX_I2C_STATUS_MAST_WR_ADDR_2_ACK
: /* 0xd0 */
158 case MV64XXX_I2C_STATUS_MAST_WR_ACK
: /* 0x28 */
159 if ((drv_data
->bytes_left
== 0)
160 || (drv_data
->aborting
161 && (drv_data
->byte_posn
!= 0))) {
162 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_STOP
;
163 drv_data
->state
= MV64XXX_I2C_STATE_IDLE
;
165 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_DATA
;
167 MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_ACK
;
168 drv_data
->bytes_left
--;
172 /* Performing a read */
173 case MV64XXX_I2C_STATUS_MAST_RD_ADDR_ACK
: /* 40 */
174 if (drv_data
->msg
->flags
& I2C_M_TEN
) {
175 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_ADDR_2
;
177 MV64XXX_I2C_STATE_WAITING_FOR_ADDR_2_ACK
;
181 case MV64XXX_I2C_STATUS_MAST_RD_ADDR_2_ACK
: /* 0xe0 */
182 if (drv_data
->bytes_left
== 0) {
183 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_STOP
;
184 drv_data
->state
= MV64XXX_I2C_STATE_IDLE
;
188 case MV64XXX_I2C_STATUS_MAST_RD_DATA_ACK
: /* 0x50 */
189 if (status
!= MV64XXX_I2C_STATUS_MAST_RD_DATA_ACK
)
190 drv_data
->action
= MV64XXX_I2C_ACTION_CONTINUE
;
192 drv_data
->action
= MV64XXX_I2C_ACTION_RCV_DATA
;
193 drv_data
->bytes_left
--;
195 drv_data
->state
= MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_DATA
;
197 if ((drv_data
->bytes_left
== 1) || drv_data
->aborting
)
198 drv_data
->cntl_bits
&= ~MV64XXX_I2C_REG_CONTROL_ACK
;
201 case MV64XXX_I2C_STATUS_MAST_RD_DATA_NO_ACK
: /* 0x58 */
202 drv_data
->action
= MV64XXX_I2C_ACTION_RCV_DATA_STOP
;
203 drv_data
->state
= MV64XXX_I2C_STATE_IDLE
;
206 case MV64XXX_I2C_STATUS_MAST_WR_ADDR_NO_ACK
: /* 0x20 */
207 case MV64XXX_I2C_STATUS_MAST_WR_NO_ACK
: /* 30 */
208 case MV64XXX_I2C_STATUS_MAST_RD_ADDR_NO_ACK
: /* 48 */
209 /* Doesn't seem to be a device at other end */
210 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_STOP
;
211 drv_data
->state
= MV64XXX_I2C_STATE_IDLE
;
212 drv_data
->rc
= -ENODEV
;
216 dev_err(&drv_data
->adapter
.dev
,
217 "mv64xxx_i2c_fsm: Ctlr Error -- state: 0x%x, "
218 "status: 0x%x, addr: 0x%x, flags: 0x%x\n",
219 drv_data
->state
, status
, drv_data
->msg
->addr
,
220 drv_data
->msg
->flags
);
221 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_STOP
;
222 mv64xxx_i2c_hw_init(drv_data
);
228 mv64xxx_i2c_do_action(struct mv64xxx_i2c_data
*drv_data
)
230 switch(drv_data
->action
) {
231 case MV64XXX_I2C_ACTION_CONTINUE
:
232 writel(drv_data
->cntl_bits
,
233 drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
);
236 case MV64XXX_I2C_ACTION_SEND_START
:
237 writel(drv_data
->cntl_bits
| MV64XXX_I2C_REG_CONTROL_START
,
238 drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
);
241 case MV64XXX_I2C_ACTION_SEND_ADDR_1
:
242 writel(drv_data
->addr1
,
243 drv_data
->reg_base
+ MV64XXX_I2C_REG_DATA
);
244 writel(drv_data
->cntl_bits
,
245 drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
);
248 case MV64XXX_I2C_ACTION_SEND_ADDR_2
:
249 writel(drv_data
->addr2
,
250 drv_data
->reg_base
+ MV64XXX_I2C_REG_DATA
);
251 writel(drv_data
->cntl_bits
,
252 drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
);
255 case MV64XXX_I2C_ACTION_SEND_DATA
:
256 writel(drv_data
->msg
->buf
[drv_data
->byte_posn
++],
257 drv_data
->reg_base
+ MV64XXX_I2C_REG_DATA
);
258 writel(drv_data
->cntl_bits
,
259 drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
);
262 case MV64XXX_I2C_ACTION_RCV_DATA
:
263 drv_data
->msg
->buf
[drv_data
->byte_posn
++] =
264 readl(drv_data
->reg_base
+ MV64XXX_I2C_REG_DATA
);
265 writel(drv_data
->cntl_bits
,
266 drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
);
269 case MV64XXX_I2C_ACTION_RCV_DATA_STOP
:
270 drv_data
->msg
->buf
[drv_data
->byte_posn
++] =
271 readl(drv_data
->reg_base
+ MV64XXX_I2C_REG_DATA
);
272 drv_data
->cntl_bits
&= ~MV64XXX_I2C_REG_CONTROL_INTEN
;
273 writel(drv_data
->cntl_bits
| MV64XXX_I2C_REG_CONTROL_STOP
,
274 drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
);
276 wake_up_interruptible(&drv_data
->waitq
);
279 case MV64XXX_I2C_ACTION_INVALID
:
281 dev_err(&drv_data
->adapter
.dev
,
282 "mv64xxx_i2c_do_action: Invalid action: %d\n",
286 case MV64XXX_I2C_ACTION_SEND_STOP
:
287 drv_data
->cntl_bits
&= ~MV64XXX_I2C_REG_CONTROL_INTEN
;
288 writel(drv_data
->cntl_bits
| MV64XXX_I2C_REG_CONTROL_STOP
,
289 drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
);
291 wake_up_interruptible(&drv_data
->waitq
);
297 mv64xxx_i2c_intr(int irq
, void *dev_id
)
299 struct mv64xxx_i2c_data
*drv_data
= dev_id
;
304 spin_lock_irqsave(&drv_data
->lock
, flags
);
305 while (readl(drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
) &
306 MV64XXX_I2C_REG_CONTROL_IFLG
) {
307 status
= readl(drv_data
->reg_base
+ MV64XXX_I2C_REG_STATUS
);
308 mv64xxx_i2c_fsm(drv_data
, status
);
309 mv64xxx_i2c_do_action(drv_data
);
312 spin_unlock_irqrestore(&drv_data
->lock
, flags
);
318 *****************************************************************************
320 * I2C Msg Execution Routines
322 *****************************************************************************
325 mv64xxx_i2c_prepare_for_io(struct mv64xxx_i2c_data
*drv_data
,
331 drv_data
->byte_posn
= 0;
332 drv_data
->bytes_left
= msg
->len
;
333 drv_data
->aborting
= 0;
335 drv_data
->cntl_bits
= MV64XXX_I2C_REG_CONTROL_ACK
|
336 MV64XXX_I2C_REG_CONTROL_INTEN
| MV64XXX_I2C_REG_CONTROL_TWSIEN
;
338 if (msg
->flags
& I2C_M_RD
)
341 if (msg
->flags
& I2C_M_REV_DIR_ADDR
)
344 if (msg
->flags
& I2C_M_TEN
) {
345 drv_data
->addr1
= 0xf0 | (((u32
)msg
->addr
& 0x300) >> 7) | dir
;
346 drv_data
->addr2
= (u32
)msg
->addr
& 0xff;
348 drv_data
->addr1
= ((u32
)msg
->addr
& 0x7f) << 1 | dir
;
354 mv64xxx_i2c_wait_for_completion(struct mv64xxx_i2c_data
*drv_data
)
360 time_left
= wait_event_interruptible_timeout(drv_data
->waitq
,
361 !drv_data
->block
, drv_data
->adapter
.timeout
);
363 spin_lock_irqsave(&drv_data
->lock
, flags
);
364 if (!time_left
) { /* Timed out */
365 drv_data
->rc
= -ETIMEDOUT
;
367 } else if (time_left
< 0) { /* Interrupted/Error */
368 drv_data
->rc
= time_left
; /* errno value */
372 if (abort
&& drv_data
->block
) {
373 drv_data
->aborting
= 1;
374 spin_unlock_irqrestore(&drv_data
->lock
, flags
);
376 time_left
= wait_event_timeout(drv_data
->waitq
,
377 !drv_data
->block
, 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
)
467 struct resource
*r
= platform_get_resource(pd
, IORESOURCE_MEM
, 0);
472 size
= resource_size(r
);
474 if (!request_mem_region(r
->start
, size
, drv_data
->adapter
.name
))
477 drv_data
->reg_base
= ioremap(r
->start
, size
);
478 drv_data
->reg_base_p
= r
->start
;
479 drv_data
->reg_size
= size
;
485 mv64xxx_i2c_unmap_regs(struct mv64xxx_i2c_data
*drv_data
)
487 if (drv_data
->reg_base
) {
488 iounmap(drv_data
->reg_base
);
489 release_mem_region(drv_data
->reg_base_p
, drv_data
->reg_size
);
492 drv_data
->reg_base
= NULL
;
493 drv_data
->reg_base_p
= 0;
497 mv64xxx_i2c_probe(struct platform_device
*pd
)
499 struct mv64xxx_i2c_data
*drv_data
;
500 struct mv64xxx_i2c_pdata
*pdata
= pd
->dev
.platform_data
;
503 if ((pd
->id
!= 0) || !pdata
)
506 drv_data
= kzalloc(sizeof(struct mv64xxx_i2c_data
), GFP_KERNEL
);
510 if (mv64xxx_i2c_map_regs(pd
, drv_data
)) {
515 strlcpy(drv_data
->adapter
.name
, MV64XXX_I2C_CTLR_NAME
" adapter",
516 sizeof(drv_data
->adapter
.name
));
518 init_waitqueue_head(&drv_data
->waitq
);
519 spin_lock_init(&drv_data
->lock
);
521 drv_data
->freq_m
= pdata
->freq_m
;
522 drv_data
->freq_n
= pdata
->freq_n
;
523 drv_data
->irq
= platform_get_irq(pd
, 0);
524 if (drv_data
->irq
< 0) {
526 goto exit_unmap_regs
;
528 drv_data
->adapter
.dev
.parent
= &pd
->dev
;
529 drv_data
->adapter
.algo
= &mv64xxx_i2c_algo
;
530 drv_data
->adapter
.owner
= THIS_MODULE
;
531 drv_data
->adapter
.class = I2C_CLASS_HWMON
| I2C_CLASS_SPD
;
532 drv_data
->adapter
.timeout
= msecs_to_jiffies(pdata
->timeout
);
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
= __devexit_p(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");