2 * drivers/i2c/busses/i2c-mv64xxx.c
4 * Driver for the i2c controller on the Marvell line of host bridges for MIPS
5 * and PPC (e.g, gt642[46]0, mv643[46]0, mv644[46]0).
7 * Author: Mark A. Greer <mgreer@mvista.com>
9 * 2005 (c) MontaVista, Software, Inc. This file is licensed under
10 * the terms of the GNU General Public License version 2. This program
11 * is licensed "as is" without any warranty of any kind, whether express
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/spinlock.h>
17 #include <linux/i2c.h>
18 #include <linux/interrupt.h>
19 #include <linux/mv643xx.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
,
66 MV64XXX_I2C_STATE_ABORTING
,
71 MV64XXX_I2C_ACTION_INVALID
,
72 MV64XXX_I2C_ACTION_CONTINUE
,
73 MV64XXX_I2C_ACTION_SEND_START
,
74 MV64XXX_I2C_ACTION_SEND_ADDR_1
,
75 MV64XXX_I2C_ACTION_SEND_ADDR_2
,
76 MV64XXX_I2C_ACTION_SEND_DATA
,
77 MV64XXX_I2C_ACTION_RCV_DATA
,
78 MV64XXX_I2C_ACTION_RCV_DATA_STOP
,
79 MV64XXX_I2C_ACTION_SEND_STOP
,
82 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 mv64xxx_i2c_fsm(struct mv64xxx_i2c_data
*drv_data
, u32 status
)
114 * If state is idle, then this is likely the remnants of an old
115 * operation that driver has given up on or the user has killed.
116 * If so, issue the stop condition and go to idle.
118 if (drv_data
->state
== MV64XXX_I2C_STATE_IDLE
) {
119 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_STOP
;
123 if (drv_data
->state
== MV64XXX_I2C_STATE_ABORTING
) {
124 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_STOP
;
125 drv_data
->state
= MV64XXX_I2C_STATE_IDLE
;
129 /* The status from the ctlr [mostly] tells us what to do next */
131 /* Start condition interrupt */
132 case MV64XXX_I2C_STATUS_MAST_START
: /* 0x08 */
133 case MV64XXX_I2C_STATUS_MAST_REPEAT_START
: /* 0x10 */
134 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_ADDR_1
;
135 drv_data
->state
= MV64XXX_I2C_STATE_WAITING_FOR_ADDR_1_ACK
;
138 /* Performing a write */
139 case MV64XXX_I2C_STATUS_MAST_WR_ADDR_ACK
: /* 0x18 */
140 if (drv_data
->msg
->flags
& I2C_M_TEN
) {
141 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_ADDR_2
;
143 MV64XXX_I2C_STATE_WAITING_FOR_ADDR_2_ACK
;
147 case MV64XXX_I2C_STATUS_MAST_WR_ADDR_2_ACK
: /* 0xd0 */
148 case MV64XXX_I2C_STATUS_MAST_WR_ACK
: /* 0x28 */
149 if (drv_data
->bytes_left
> 0) {
150 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_DATA
;
152 MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_ACK
;
153 drv_data
->bytes_left
--;
155 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_STOP
;
156 drv_data
->state
= MV64XXX_I2C_STATE_IDLE
;
160 /* Performing a read */
161 case MV64XXX_I2C_STATUS_MAST_RD_ADDR_ACK
: /* 40 */
162 if (drv_data
->msg
->flags
& I2C_M_TEN
) {
163 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_ADDR_2
;
165 MV64XXX_I2C_STATE_WAITING_FOR_ADDR_2_ACK
;
169 case MV64XXX_I2C_STATUS_MAST_RD_ADDR_2_ACK
: /* 0xe0 */
170 if (drv_data
->bytes_left
== 0) {
171 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_STOP
;
172 drv_data
->state
= MV64XXX_I2C_STATE_IDLE
;
176 case MV64XXX_I2C_STATUS_MAST_RD_DATA_ACK
: /* 0x50 */
177 if (status
!= MV64XXX_I2C_STATUS_MAST_RD_DATA_ACK
)
178 drv_data
->action
= MV64XXX_I2C_ACTION_CONTINUE
;
180 drv_data
->action
= MV64XXX_I2C_ACTION_RCV_DATA
;
181 drv_data
->bytes_left
--;
183 drv_data
->state
= MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_DATA
;
185 if (drv_data
->bytes_left
== 1)
186 drv_data
->cntl_bits
&= ~MV64XXX_I2C_REG_CONTROL_ACK
;
189 case MV64XXX_I2C_STATUS_MAST_RD_DATA_NO_ACK
: /* 0x58 */
190 drv_data
->action
= MV64XXX_I2C_ACTION_RCV_DATA_STOP
;
191 drv_data
->state
= MV64XXX_I2C_STATE_IDLE
;
194 case MV64XXX_I2C_STATUS_MAST_WR_ADDR_NO_ACK
: /* 0x20 */
195 case MV64XXX_I2C_STATUS_MAST_WR_NO_ACK
: /* 30 */
196 case MV64XXX_I2C_STATUS_MAST_RD_ADDR_NO_ACK
: /* 48 */
197 /* Doesn't seem to be a device at other end */
198 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_STOP
;
199 drv_data
->state
= MV64XXX_I2C_STATE_IDLE
;
200 drv_data
->rc
= -ENODEV
;
204 dev_err(&drv_data
->adapter
.dev
,
205 "mv64xxx_i2c_fsm: Ctlr Error -- state: 0x%x, "
206 "status: 0x%x, addr: 0x%x, flags: 0x%x\n",
207 drv_data
->state
, status
, drv_data
->msg
->addr
,
208 drv_data
->msg
->flags
);
209 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_STOP
;
210 drv_data
->state
= MV64XXX_I2C_STATE_IDLE
;
216 mv64xxx_i2c_do_action(struct mv64xxx_i2c_data
*drv_data
)
218 switch(drv_data
->action
) {
219 case MV64XXX_I2C_ACTION_CONTINUE
:
220 writel(drv_data
->cntl_bits
,
221 drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
);
224 case MV64XXX_I2C_ACTION_SEND_START
:
225 writel(drv_data
->cntl_bits
| MV64XXX_I2C_REG_CONTROL_START
,
226 drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
);
229 case MV64XXX_I2C_ACTION_SEND_ADDR_1
:
230 writel(drv_data
->addr1
,
231 drv_data
->reg_base
+ MV64XXX_I2C_REG_DATA
);
232 writel(drv_data
->cntl_bits
,
233 drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
);
236 case MV64XXX_I2C_ACTION_SEND_ADDR_2
:
237 writel(drv_data
->addr2
,
238 drv_data
->reg_base
+ MV64XXX_I2C_REG_DATA
);
239 writel(drv_data
->cntl_bits
,
240 drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
);
243 case MV64XXX_I2C_ACTION_SEND_DATA
:
244 writel(drv_data
->msg
->buf
[drv_data
->byte_posn
++],
245 drv_data
->reg_base
+ MV64XXX_I2C_REG_DATA
);
246 writel(drv_data
->cntl_bits
,
247 drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
);
250 case MV64XXX_I2C_ACTION_RCV_DATA
:
251 drv_data
->msg
->buf
[drv_data
->byte_posn
++] =
252 readl(drv_data
->reg_base
+ MV64XXX_I2C_REG_DATA
);
253 writel(drv_data
->cntl_bits
,
254 drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
);
257 case MV64XXX_I2C_ACTION_RCV_DATA_STOP
:
258 drv_data
->msg
->buf
[drv_data
->byte_posn
++] =
259 readl(drv_data
->reg_base
+ MV64XXX_I2C_REG_DATA
);
260 drv_data
->cntl_bits
&= ~MV64XXX_I2C_REG_CONTROL_INTEN
;
261 writel(drv_data
->cntl_bits
| MV64XXX_I2C_REG_CONTROL_STOP
,
262 drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
);
264 wake_up_interruptible(&drv_data
->waitq
);
267 case MV64XXX_I2C_ACTION_INVALID
:
269 dev_err(&drv_data
->adapter
.dev
,
270 "mv64xxx_i2c_do_action: Invalid action: %d\n",
274 case MV64XXX_I2C_ACTION_SEND_STOP
:
275 drv_data
->cntl_bits
&= ~MV64XXX_I2C_REG_CONTROL_INTEN
;
276 writel(drv_data
->cntl_bits
| MV64XXX_I2C_REG_CONTROL_STOP
,
277 drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
);
279 wake_up_interruptible(&drv_data
->waitq
);
285 mv64xxx_i2c_intr(int irq
, void *dev_id
, struct pt_regs
*regs
)
287 struct mv64xxx_i2c_data
*drv_data
= dev_id
;
292 spin_lock_irqsave(&drv_data
->lock
, flags
);
293 while (readl(drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
) &
294 MV64XXX_I2C_REG_CONTROL_IFLG
) {
295 status
= readl(drv_data
->reg_base
+ MV64XXX_I2C_REG_STATUS
);
296 mv64xxx_i2c_fsm(drv_data
, status
);
297 mv64xxx_i2c_do_action(drv_data
);
300 spin_unlock_irqrestore(&drv_data
->lock
, flags
);
306 *****************************************************************************
308 * I2C Msg Execution Routines
310 *****************************************************************************
313 mv64xxx_i2c_prepare_for_io(struct mv64xxx_i2c_data
*drv_data
,
319 drv_data
->byte_posn
= 0;
320 drv_data
->bytes_left
= msg
->len
;
322 drv_data
->cntl_bits
= MV64XXX_I2C_REG_CONTROL_ACK
|
323 MV64XXX_I2C_REG_CONTROL_INTEN
| MV64XXX_I2C_REG_CONTROL_TWSIEN
;
325 if (msg
->flags
& I2C_M_RD
)
328 if (msg
->flags
& I2C_M_REV_DIR_ADDR
)
331 if (msg
->flags
& I2C_M_TEN
) {
332 drv_data
->addr1
= 0xf0 | (((u32
)msg
->addr
& 0x300) >> 7) | dir
;
333 drv_data
->addr2
= (u32
)msg
->addr
& 0xff;
335 drv_data
->addr1
= ((u32
)msg
->addr
& 0x7f) << 1 | dir
;
341 mv64xxx_i2c_wait_for_completion(struct mv64xxx_i2c_data
*drv_data
)
347 time_left
= wait_event_interruptible_timeout(drv_data
->waitq
,
348 !drv_data
->block
, msecs_to_jiffies(drv_data
->adapter
.timeout
));
350 spin_lock_irqsave(&drv_data
->lock
, flags
);
351 if (!time_left
) { /* Timed out */
352 drv_data
->rc
= -ETIMEDOUT
;
354 } else if (time_left
< 0) { /* Interrupted/Error */
355 drv_data
->rc
= time_left
; /* errno value */
359 if (abort
&& drv_data
->block
) {
360 drv_data
->state
= MV64XXX_I2C_STATE_ABORTING
;
361 spin_unlock_irqrestore(&drv_data
->lock
, flags
);
363 time_left
= wait_event_timeout(drv_data
->waitq
,
365 msecs_to_jiffies(drv_data
->adapter
.timeout
));
367 if (time_left
<= 0) {
368 drv_data
->state
= MV64XXX_I2C_STATE_IDLE
;
369 dev_err(&drv_data
->adapter
.dev
,
370 "mv64xxx: I2C bus locked\n");
373 spin_unlock_irqrestore(&drv_data
->lock
, flags
);
377 mv64xxx_i2c_execute_msg(struct mv64xxx_i2c_data
*drv_data
, struct i2c_msg
*msg
)
381 spin_lock_irqsave(&drv_data
->lock
, flags
);
382 mv64xxx_i2c_prepare_for_io(drv_data
, msg
);
384 if (unlikely(msg
->flags
& I2C_M_NOSTART
)) { /* Skip start/addr phases */
385 if (drv_data
->msg
->flags
& I2C_M_RD
) {
386 /* No action to do, wait for slave to send a byte */
387 drv_data
->action
= MV64XXX_I2C_ACTION_CONTINUE
;
389 MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_DATA
;
391 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_DATA
;
393 MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_ACK
;
394 drv_data
->bytes_left
--;
397 drv_data
->action
= MV64XXX_I2C_ACTION_SEND_START
;
398 drv_data
->state
= MV64XXX_I2C_STATE_WAITING_FOR_START_COND
;
402 mv64xxx_i2c_do_action(drv_data
);
403 spin_unlock_irqrestore(&drv_data
->lock
, flags
);
405 mv64xxx_i2c_wait_for_completion(drv_data
);
410 *****************************************************************************
412 * I2C Core Support Routines (Interface to higher level I2C code)
414 *****************************************************************************
417 mv64xxx_i2c_functionality(struct i2c_adapter
*adap
)
419 return I2C_FUNC_I2C
| I2C_FUNC_10BIT_ADDR
| I2C_FUNC_SMBUS_EMUL
;
423 mv64xxx_i2c_xfer(struct i2c_adapter
*adap
, struct i2c_msg msgs
[], int num
)
425 struct mv64xxx_i2c_data
*drv_data
= i2c_get_adapdata(adap
);
428 for (i
=0; i
<num
; i
++)
429 if ((rc
= mv64xxx_i2c_execute_msg(drv_data
, &msgs
[i
])) != 0)
435 static struct i2c_algorithm mv64xxx_i2c_algo
= {
436 .name
= MV64XXX_I2C_CTLR_NAME
" algorithm",
437 .id
= I2C_ALGO_MV64XXX
,
438 .master_xfer
= mv64xxx_i2c_xfer
,
439 .functionality
= mv64xxx_i2c_functionality
,
443 *****************************************************************************
445 * Driver Interface & Early Init Routines
447 *****************************************************************************
449 static void __devinit
450 mv64xxx_i2c_hw_init(struct mv64xxx_i2c_data
*drv_data
)
452 writel(0, drv_data
->reg_base
+ MV64XXX_I2C_REG_SOFT_RESET
);
453 writel((((drv_data
->freq_m
& 0xf) << 3) | (drv_data
->freq_n
& 0x7)),
454 drv_data
->reg_base
+ MV64XXX_I2C_REG_BAUD
);
455 writel(0, drv_data
->reg_base
+ MV64XXX_I2C_REG_SLAVE_ADDR
);
456 writel(0, drv_data
->reg_base
+ MV64XXX_I2C_REG_EXT_SLAVE_ADDR
);
457 writel(MV64XXX_I2C_REG_CONTROL_TWSIEN
| MV64XXX_I2C_REG_CONTROL_STOP
,
458 drv_data
->reg_base
+ MV64XXX_I2C_REG_CONTROL
);
459 drv_data
->state
= MV64XXX_I2C_STATE_IDLE
;
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 device
*dev
)
497 struct platform_device
*pd
= to_platform_device(dev
);
498 struct mv64xxx_i2c_data
*drv_data
;
499 struct mv64xxx_i2c_pdata
*pdata
= dev
->platform_data
;
502 if ((pd
->id
!= 0) || !pdata
)
505 drv_data
= kmalloc(sizeof(struct mv64xxx_i2c_data
), GFP_KERNEL
);
510 memset(drv_data
, 0, sizeof(struct mv64xxx_i2c_data
));
512 if (mv64xxx_i2c_map_regs(pd
, drv_data
)) {
517 strncpy(drv_data
->adapter
.name
, MV64XXX_I2C_CTLR_NAME
" adapter",
520 init_waitqueue_head(&drv_data
->waitq
);
521 spin_lock_init(&drv_data
->lock
);
523 drv_data
->freq_m
= pdata
->freq_m
;
524 drv_data
->freq_n
= pdata
->freq_n
;
525 drv_data
->irq
= platform_get_irq(pd
, 0);
526 drv_data
->adapter
.id
= I2C_ALGO_MV64XXX
| I2C_HW_MV64XXX
;
527 drv_data
->adapter
.algo
= &mv64xxx_i2c_algo
;
528 drv_data
->adapter
.owner
= THIS_MODULE
;
529 drv_data
->adapter
.class = I2C_CLASS_HWMON
;
530 drv_data
->adapter
.timeout
= pdata
->timeout
;
531 drv_data
->adapter
.retries
= pdata
->retries
;
532 dev_set_drvdata(dev
, drv_data
);
533 i2c_set_adapdata(&drv_data
->adapter
, drv_data
);
535 if (request_irq(drv_data
->irq
, mv64xxx_i2c_intr
, 0,
536 MV64XXX_I2C_CTLR_NAME
, drv_data
)) {
538 dev_err(dev
, "mv64xxx: Can't register intr handler "
539 "irq: %d\n", drv_data
->irq
);
541 goto exit_unmap_regs
;
542 } else if ((rc
= i2c_add_adapter(&drv_data
->adapter
)) != 0) {
543 dev_err(dev
, "mv64xxx: Can't add i2c adapter, rc: %d\n", -rc
);
547 mv64xxx_i2c_hw_init(drv_data
);
552 free_irq(drv_data
->irq
, drv_data
);
554 mv64xxx_i2c_unmap_regs(drv_data
);
561 mv64xxx_i2c_remove(struct device
*dev
)
563 struct mv64xxx_i2c_data
*drv_data
= dev_get_drvdata(dev
);
566 rc
= i2c_del_adapter(&drv_data
->adapter
);
567 free_irq(drv_data
->irq
, drv_data
);
568 mv64xxx_i2c_unmap_regs(drv_data
);
574 static struct device_driver mv64xxx_i2c_driver
= {
575 .name
= MV64XXX_I2C_CTLR_NAME
,
576 .bus
= &platform_bus_type
,
577 .probe
= mv64xxx_i2c_probe
,
578 .remove
= mv64xxx_i2c_remove
,
582 mv64xxx_i2c_init(void)
584 return driver_register(&mv64xxx_i2c_driver
);
588 mv64xxx_i2c_exit(void)
590 driver_unregister(&mv64xxx_i2c_driver
);
593 module_init(mv64xxx_i2c_init
);
594 module_exit(mv64xxx_i2c_exit
);
596 MODULE_AUTHOR("Mark A. Greer <mgreer@mvista.com>");
597 MODULE_DESCRIPTION("Marvell mv64xxx host bridge i2c ctlr driver");
598 MODULE_LICENSE("GPL");