xref: /openbmc/linux/drivers/i2c/busses/i2c-mv64xxx.c (revision 565d76cb)
1 /*
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).
4  *
5  * Author: Mark A. Greer <mgreer@mvista.com>
6  *
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
10  * or implied.
11  */
12 #include <linux/kernel.h>
13 #include <linux/slab.h>
14 #include <linux/module.h>
15 #include <linux/spinlock.h>
16 #include <linux/i2c.h>
17 #include <linux/interrupt.h>
18 #include <linux/mv643xx_i2c.h>
19 #include <linux/platform_device.h>
20 #include <linux/io.h>
21 
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
30 
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
37 
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
56 
57 /* Driver states */
58 enum {
59 	MV64XXX_I2C_STATE_INVALID,
60 	MV64XXX_I2C_STATE_IDLE,
61 	MV64XXX_I2C_STATE_WAITING_FOR_START_COND,
62 	MV64XXX_I2C_STATE_WAITING_FOR_RESTART,
63 	MV64XXX_I2C_STATE_WAITING_FOR_ADDR_1_ACK,
64 	MV64XXX_I2C_STATE_WAITING_FOR_ADDR_2_ACK,
65 	MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_ACK,
66 	MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_DATA,
67 };
68 
69 /* Driver actions */
70 enum {
71 	MV64XXX_I2C_ACTION_INVALID,
72 	MV64XXX_I2C_ACTION_CONTINUE,
73 	MV64XXX_I2C_ACTION_SEND_START,
74 	MV64XXX_I2C_ACTION_SEND_RESTART,
75 	MV64XXX_I2C_ACTION_SEND_ADDR_1,
76 	MV64XXX_I2C_ACTION_SEND_ADDR_2,
77 	MV64XXX_I2C_ACTION_SEND_DATA,
78 	MV64XXX_I2C_ACTION_RCV_DATA,
79 	MV64XXX_I2C_ACTION_RCV_DATA_STOP,
80 	MV64XXX_I2C_ACTION_SEND_STOP,
81 };
82 
83 struct mv64xxx_i2c_data {
84 	int			irq;
85 	u32			state;
86 	u32			action;
87 	u32			aborting;
88 	u32			cntl_bits;
89 	void __iomem		*reg_base;
90 	u32			reg_base_p;
91 	u32			reg_size;
92 	u32			addr1;
93 	u32			addr2;
94 	u32			bytes_left;
95 	u32			byte_posn;
96 	u32			send_stop;
97 	u32			block;
98 	int			rc;
99 	u32			freq_m;
100 	u32			freq_n;
101 	wait_queue_head_t	waitq;
102 	spinlock_t		lock;
103 	struct i2c_msg		*msg;
104 	struct i2c_adapter	adapter;
105 };
106 
107 /*
108  *****************************************************************************
109  *
110  *	Finite State Machine & Interrupt Routines
111  *
112  *****************************************************************************
113  */
114 
115 /* Reset hardware and initialize FSM */
116 static void
117 mv64xxx_i2c_hw_init(struct mv64xxx_i2c_data *drv_data)
118 {
119 	writel(0, drv_data->reg_base + MV64XXX_I2C_REG_SOFT_RESET);
120 	writel((((drv_data->freq_m & 0xf) << 3) | (drv_data->freq_n & 0x7)),
121 		drv_data->reg_base + MV64XXX_I2C_REG_BAUD);
122 	writel(0, drv_data->reg_base + MV64XXX_I2C_REG_SLAVE_ADDR);
123 	writel(0, drv_data->reg_base + MV64XXX_I2C_REG_EXT_SLAVE_ADDR);
124 	writel(MV64XXX_I2C_REG_CONTROL_TWSIEN | MV64XXX_I2C_REG_CONTROL_STOP,
125 		drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
126 	drv_data->state = MV64XXX_I2C_STATE_IDLE;
127 }
128 
129 static void
130 mv64xxx_i2c_fsm(struct mv64xxx_i2c_data *drv_data, u32 status)
131 {
132 	/*
133 	 * If state is idle, then this is likely the remnants of an old
134 	 * operation that driver has given up on or the user has killed.
135 	 * If so, issue the stop condition and go to idle.
136 	 */
137 	if (drv_data->state == MV64XXX_I2C_STATE_IDLE) {
138 		drv_data->action = MV64XXX_I2C_ACTION_SEND_STOP;
139 		return;
140 	}
141 
142 	/* The status from the ctlr [mostly] tells us what to do next */
143 	switch (status) {
144 	/* Start condition interrupt */
145 	case MV64XXX_I2C_STATUS_MAST_START: /* 0x08 */
146 	case MV64XXX_I2C_STATUS_MAST_REPEAT_START: /* 0x10 */
147 		drv_data->action = MV64XXX_I2C_ACTION_SEND_ADDR_1;
148 		drv_data->state = MV64XXX_I2C_STATE_WAITING_FOR_ADDR_1_ACK;
149 		break;
150 
151 	/* Performing a write */
152 	case MV64XXX_I2C_STATUS_MAST_WR_ADDR_ACK: /* 0x18 */
153 		if (drv_data->msg->flags & I2C_M_TEN) {
154 			drv_data->action = MV64XXX_I2C_ACTION_SEND_ADDR_2;
155 			drv_data->state =
156 				MV64XXX_I2C_STATE_WAITING_FOR_ADDR_2_ACK;
157 			break;
158 		}
159 		/* FALLTHRU */
160 	case MV64XXX_I2C_STATUS_MAST_WR_ADDR_2_ACK: /* 0xd0 */
161 	case MV64XXX_I2C_STATUS_MAST_WR_ACK: /* 0x28 */
162 		if ((drv_data->bytes_left == 0)
163 				|| (drv_data->aborting
164 					&& (drv_data->byte_posn != 0))) {
165 			if (drv_data->send_stop) {
166 				drv_data->action = MV64XXX_I2C_ACTION_SEND_STOP;
167 				drv_data->state = MV64XXX_I2C_STATE_IDLE;
168 			} else {
169 				drv_data->action =
170 					MV64XXX_I2C_ACTION_SEND_RESTART;
171 				drv_data->state =
172 					MV64XXX_I2C_STATE_WAITING_FOR_RESTART;
173 			}
174 		} else {
175 			drv_data->action = MV64XXX_I2C_ACTION_SEND_DATA;
176 			drv_data->state =
177 				MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_ACK;
178 			drv_data->bytes_left--;
179 		}
180 		break;
181 
182 	/* Performing a read */
183 	case MV64XXX_I2C_STATUS_MAST_RD_ADDR_ACK: /* 40 */
184 		if (drv_data->msg->flags & I2C_M_TEN) {
185 			drv_data->action = MV64XXX_I2C_ACTION_SEND_ADDR_2;
186 			drv_data->state =
187 				MV64XXX_I2C_STATE_WAITING_FOR_ADDR_2_ACK;
188 			break;
189 		}
190 		/* FALLTHRU */
191 	case MV64XXX_I2C_STATUS_MAST_RD_ADDR_2_ACK: /* 0xe0 */
192 		if (drv_data->bytes_left == 0) {
193 			drv_data->action = MV64XXX_I2C_ACTION_SEND_STOP;
194 			drv_data->state = MV64XXX_I2C_STATE_IDLE;
195 			break;
196 		}
197 		/* FALLTHRU */
198 	case MV64XXX_I2C_STATUS_MAST_RD_DATA_ACK: /* 0x50 */
199 		if (status != MV64XXX_I2C_STATUS_MAST_RD_DATA_ACK)
200 			drv_data->action = MV64XXX_I2C_ACTION_CONTINUE;
201 		else {
202 			drv_data->action = MV64XXX_I2C_ACTION_RCV_DATA;
203 			drv_data->bytes_left--;
204 		}
205 		drv_data->state = MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_DATA;
206 
207 		if ((drv_data->bytes_left == 1) || drv_data->aborting)
208 			drv_data->cntl_bits &= ~MV64XXX_I2C_REG_CONTROL_ACK;
209 		break;
210 
211 	case MV64XXX_I2C_STATUS_MAST_RD_DATA_NO_ACK: /* 0x58 */
212 		drv_data->action = MV64XXX_I2C_ACTION_RCV_DATA_STOP;
213 		drv_data->state = MV64XXX_I2C_STATE_IDLE;
214 		break;
215 
216 	case MV64XXX_I2C_STATUS_MAST_WR_ADDR_NO_ACK: /* 0x20 */
217 	case MV64XXX_I2C_STATUS_MAST_WR_NO_ACK: /* 30 */
218 	case MV64XXX_I2C_STATUS_MAST_RD_ADDR_NO_ACK: /* 48 */
219 		/* Doesn't seem to be a device at other end */
220 		drv_data->action = MV64XXX_I2C_ACTION_SEND_STOP;
221 		drv_data->state = MV64XXX_I2C_STATE_IDLE;
222 		drv_data->rc = -ENODEV;
223 		break;
224 
225 	default:
226 		dev_err(&drv_data->adapter.dev,
227 			"mv64xxx_i2c_fsm: Ctlr Error -- state: 0x%x, "
228 			"status: 0x%x, addr: 0x%x, flags: 0x%x\n",
229 			 drv_data->state, status, drv_data->msg->addr,
230 			 drv_data->msg->flags);
231 		drv_data->action = MV64XXX_I2C_ACTION_SEND_STOP;
232 		mv64xxx_i2c_hw_init(drv_data);
233 		drv_data->rc = -EIO;
234 	}
235 }
236 
237 static void
238 mv64xxx_i2c_do_action(struct mv64xxx_i2c_data *drv_data)
239 {
240 	switch(drv_data->action) {
241 	case MV64XXX_I2C_ACTION_SEND_RESTART:
242 		drv_data->cntl_bits |= MV64XXX_I2C_REG_CONTROL_START;
243 		drv_data->cntl_bits &= ~MV64XXX_I2C_REG_CONTROL_INTEN;
244 		writel(drv_data->cntl_bits,
245 			drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
246 		drv_data->block = 0;
247 		wake_up_interruptible(&drv_data->waitq);
248 		break;
249 
250 	case MV64XXX_I2C_ACTION_CONTINUE:
251 		writel(drv_data->cntl_bits,
252 			drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
253 		break;
254 
255 	case MV64XXX_I2C_ACTION_SEND_START:
256 		writel(drv_data->cntl_bits | MV64XXX_I2C_REG_CONTROL_START,
257 			drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
258 		break;
259 
260 	case MV64XXX_I2C_ACTION_SEND_ADDR_1:
261 		writel(drv_data->addr1,
262 			drv_data->reg_base + MV64XXX_I2C_REG_DATA);
263 		writel(drv_data->cntl_bits,
264 			drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
265 		break;
266 
267 	case MV64XXX_I2C_ACTION_SEND_ADDR_2:
268 		writel(drv_data->addr2,
269 			drv_data->reg_base + MV64XXX_I2C_REG_DATA);
270 		writel(drv_data->cntl_bits,
271 			drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
272 		break;
273 
274 	case MV64XXX_I2C_ACTION_SEND_DATA:
275 		writel(drv_data->msg->buf[drv_data->byte_posn++],
276 			drv_data->reg_base + MV64XXX_I2C_REG_DATA);
277 		writel(drv_data->cntl_bits,
278 			drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
279 		break;
280 
281 	case MV64XXX_I2C_ACTION_RCV_DATA:
282 		drv_data->msg->buf[drv_data->byte_posn++] =
283 			readl(drv_data->reg_base + MV64XXX_I2C_REG_DATA);
284 		writel(drv_data->cntl_bits,
285 			drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
286 		break;
287 
288 	case MV64XXX_I2C_ACTION_RCV_DATA_STOP:
289 		drv_data->msg->buf[drv_data->byte_posn++] =
290 			readl(drv_data->reg_base + MV64XXX_I2C_REG_DATA);
291 		drv_data->cntl_bits &= ~MV64XXX_I2C_REG_CONTROL_INTEN;
292 		writel(drv_data->cntl_bits | MV64XXX_I2C_REG_CONTROL_STOP,
293 			drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
294 		drv_data->block = 0;
295 		wake_up_interruptible(&drv_data->waitq);
296 		break;
297 
298 	case MV64XXX_I2C_ACTION_INVALID:
299 	default:
300 		dev_err(&drv_data->adapter.dev,
301 			"mv64xxx_i2c_do_action: Invalid action: %d\n",
302 			drv_data->action);
303 		drv_data->rc = -EIO;
304 		/* FALLTHRU */
305 	case MV64XXX_I2C_ACTION_SEND_STOP:
306 		drv_data->cntl_bits &= ~MV64XXX_I2C_REG_CONTROL_INTEN;
307 		writel(drv_data->cntl_bits | MV64XXX_I2C_REG_CONTROL_STOP,
308 			drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
309 		drv_data->block = 0;
310 		wake_up_interruptible(&drv_data->waitq);
311 		break;
312 	}
313 }
314 
315 static irqreturn_t
316 mv64xxx_i2c_intr(int irq, void *dev_id)
317 {
318 	struct mv64xxx_i2c_data	*drv_data = dev_id;
319 	unsigned long	flags;
320 	u32		status;
321 	irqreturn_t	rc = IRQ_NONE;
322 
323 	spin_lock_irqsave(&drv_data->lock, flags);
324 	while (readl(drv_data->reg_base + MV64XXX_I2C_REG_CONTROL) &
325 						MV64XXX_I2C_REG_CONTROL_IFLG) {
326 		status = readl(drv_data->reg_base + MV64XXX_I2C_REG_STATUS);
327 		mv64xxx_i2c_fsm(drv_data, status);
328 		mv64xxx_i2c_do_action(drv_data);
329 		rc = IRQ_HANDLED;
330 	}
331 	spin_unlock_irqrestore(&drv_data->lock, flags);
332 
333 	return rc;
334 }
335 
336 /*
337  *****************************************************************************
338  *
339  *	I2C Msg Execution Routines
340  *
341  *****************************************************************************
342  */
343 static void
344 mv64xxx_i2c_prepare_for_io(struct mv64xxx_i2c_data *drv_data,
345 	struct i2c_msg *msg)
346 {
347 	u32	dir = 0;
348 
349 	drv_data->msg = msg;
350 	drv_data->byte_posn = 0;
351 	drv_data->bytes_left = msg->len;
352 	drv_data->aborting = 0;
353 	drv_data->rc = 0;
354 	drv_data->cntl_bits = MV64XXX_I2C_REG_CONTROL_ACK |
355 		MV64XXX_I2C_REG_CONTROL_INTEN | MV64XXX_I2C_REG_CONTROL_TWSIEN;
356 
357 	if (msg->flags & I2C_M_RD)
358 		dir = 1;
359 
360 	if (msg->flags & I2C_M_TEN) {
361 		drv_data->addr1 = 0xf0 | (((u32)msg->addr & 0x300) >> 7) | dir;
362 		drv_data->addr2 = (u32)msg->addr & 0xff;
363 	} else {
364 		drv_data->addr1 = ((u32)msg->addr & 0x7f) << 1 | dir;
365 		drv_data->addr2 = 0;
366 	}
367 }
368 
369 static void
370 mv64xxx_i2c_wait_for_completion(struct mv64xxx_i2c_data *drv_data)
371 {
372 	long		time_left;
373 	unsigned long	flags;
374 	char		abort = 0;
375 
376 	time_left = wait_event_interruptible_timeout(drv_data->waitq,
377 		!drv_data->block, drv_data->adapter.timeout);
378 
379 	spin_lock_irqsave(&drv_data->lock, flags);
380 	if (!time_left) { /* Timed out */
381 		drv_data->rc = -ETIMEDOUT;
382 		abort = 1;
383 	} else if (time_left < 0) { /* Interrupted/Error */
384 		drv_data->rc = time_left; /* errno value */
385 		abort = 1;
386 	}
387 
388 	if (abort && drv_data->block) {
389 		drv_data->aborting = 1;
390 		spin_unlock_irqrestore(&drv_data->lock, flags);
391 
392 		time_left = wait_event_timeout(drv_data->waitq,
393 			!drv_data->block, drv_data->adapter.timeout);
394 
395 		if ((time_left <= 0) && drv_data->block) {
396 			drv_data->state = MV64XXX_I2C_STATE_IDLE;
397 			dev_err(&drv_data->adapter.dev,
398 				"mv64xxx: I2C bus locked, block: %d, "
399 				"time_left: %d\n", drv_data->block,
400 				(int)time_left);
401 			mv64xxx_i2c_hw_init(drv_data);
402 		}
403 	} else
404 		spin_unlock_irqrestore(&drv_data->lock, flags);
405 }
406 
407 static int
408 mv64xxx_i2c_execute_msg(struct mv64xxx_i2c_data *drv_data, struct i2c_msg *msg,
409 				int is_first, int is_last)
410 {
411 	unsigned long	flags;
412 
413 	spin_lock_irqsave(&drv_data->lock, flags);
414 	mv64xxx_i2c_prepare_for_io(drv_data, msg);
415 
416 	if (unlikely(msg->flags & I2C_M_NOSTART)) { /* Skip start/addr phases */
417 		if (drv_data->msg->flags & I2C_M_RD) {
418 			/* No action to do, wait for slave to send a byte */
419 			drv_data->action = MV64XXX_I2C_ACTION_CONTINUE;
420 			drv_data->state =
421 				MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_DATA;
422 		} else {
423 			drv_data->action = MV64XXX_I2C_ACTION_SEND_DATA;
424 			drv_data->state =
425 				MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_ACK;
426 			drv_data->bytes_left--;
427 		}
428 	} else {
429 		if (is_first) {
430 			drv_data->action = MV64XXX_I2C_ACTION_SEND_START;
431 			drv_data->state =
432 				MV64XXX_I2C_STATE_WAITING_FOR_START_COND;
433 		} else {
434 			drv_data->action = MV64XXX_I2C_ACTION_SEND_ADDR_1;
435 			drv_data->state =
436 				MV64XXX_I2C_STATE_WAITING_FOR_ADDR_1_ACK;
437 		}
438 	}
439 
440 	drv_data->send_stop = is_last;
441 	drv_data->block = 1;
442 	mv64xxx_i2c_do_action(drv_data);
443 	spin_unlock_irqrestore(&drv_data->lock, flags);
444 
445 	mv64xxx_i2c_wait_for_completion(drv_data);
446 	return drv_data->rc;
447 }
448 
449 /*
450  *****************************************************************************
451  *
452  *	I2C Core Support Routines (Interface to higher level I2C code)
453  *
454  *****************************************************************************
455  */
456 static u32
457 mv64xxx_i2c_functionality(struct i2c_adapter *adap)
458 {
459 	return I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR | I2C_FUNC_SMBUS_EMUL;
460 }
461 
462 static int
463 mv64xxx_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
464 {
465 	struct mv64xxx_i2c_data *drv_data = i2c_get_adapdata(adap);
466 	int	i, rc;
467 
468 	for (i = 0; i < num; i++) {
469 		rc = mv64xxx_i2c_execute_msg(drv_data, &msgs[i],
470 						i == 0, i + 1 == num);
471 		if (rc < 0)
472 			return rc;
473 	}
474 
475 	return num;
476 }
477 
478 static const struct i2c_algorithm mv64xxx_i2c_algo = {
479 	.master_xfer = mv64xxx_i2c_xfer,
480 	.functionality = mv64xxx_i2c_functionality,
481 };
482 
483 /*
484  *****************************************************************************
485  *
486  *	Driver Interface & Early Init Routines
487  *
488  *****************************************************************************
489  */
490 static int __devinit
491 mv64xxx_i2c_map_regs(struct platform_device *pd,
492 	struct mv64xxx_i2c_data *drv_data)
493 {
494 	int size;
495 	struct resource	*r = platform_get_resource(pd, IORESOURCE_MEM, 0);
496 
497 	if (!r)
498 		return -ENODEV;
499 
500 	size = resource_size(r);
501 
502 	if (!request_mem_region(r->start, size, drv_data->adapter.name))
503 		return -EBUSY;
504 
505 	drv_data->reg_base = ioremap(r->start, size);
506 	drv_data->reg_base_p = r->start;
507 	drv_data->reg_size = size;
508 
509 	return 0;
510 }
511 
512 static void
513 mv64xxx_i2c_unmap_regs(struct mv64xxx_i2c_data *drv_data)
514 {
515 	if (drv_data->reg_base) {
516 		iounmap(drv_data->reg_base);
517 		release_mem_region(drv_data->reg_base_p, drv_data->reg_size);
518 	}
519 
520 	drv_data->reg_base = NULL;
521 	drv_data->reg_base_p = 0;
522 }
523 
524 static int __devinit
525 mv64xxx_i2c_probe(struct platform_device *pd)
526 {
527 	struct mv64xxx_i2c_data		*drv_data;
528 	struct mv64xxx_i2c_pdata	*pdata = pd->dev.platform_data;
529 	int	rc;
530 
531 	if ((pd->id != 0) || !pdata)
532 		return -ENODEV;
533 
534 	drv_data = kzalloc(sizeof(struct mv64xxx_i2c_data), GFP_KERNEL);
535 	if (!drv_data)
536 		return -ENOMEM;
537 
538 	if (mv64xxx_i2c_map_regs(pd, drv_data)) {
539 		rc = -ENODEV;
540 		goto exit_kfree;
541 	}
542 
543 	strlcpy(drv_data->adapter.name, MV64XXX_I2C_CTLR_NAME " adapter",
544 		sizeof(drv_data->adapter.name));
545 
546 	init_waitqueue_head(&drv_data->waitq);
547 	spin_lock_init(&drv_data->lock);
548 
549 	drv_data->freq_m = pdata->freq_m;
550 	drv_data->freq_n = pdata->freq_n;
551 	drv_data->irq = platform_get_irq(pd, 0);
552 	if (drv_data->irq < 0) {
553 		rc = -ENXIO;
554 		goto exit_unmap_regs;
555 	}
556 	drv_data->adapter.dev.parent = &pd->dev;
557 	drv_data->adapter.algo = &mv64xxx_i2c_algo;
558 	drv_data->adapter.owner = THIS_MODULE;
559 	drv_data->adapter.class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
560 	drv_data->adapter.timeout = msecs_to_jiffies(pdata->timeout);
561 	drv_data->adapter.nr = pd->id;
562 	platform_set_drvdata(pd, drv_data);
563 	i2c_set_adapdata(&drv_data->adapter, drv_data);
564 
565 	mv64xxx_i2c_hw_init(drv_data);
566 
567 	if (request_irq(drv_data->irq, mv64xxx_i2c_intr, 0,
568 			MV64XXX_I2C_CTLR_NAME, drv_data)) {
569 		dev_err(&drv_data->adapter.dev,
570 			"mv64xxx: Can't register intr handler irq: %d\n",
571 			drv_data->irq);
572 		rc = -EINVAL;
573 		goto exit_unmap_regs;
574 	} else if ((rc = i2c_add_numbered_adapter(&drv_data->adapter)) != 0) {
575 		dev_err(&drv_data->adapter.dev,
576 			"mv64xxx: Can't add i2c adapter, rc: %d\n", -rc);
577 		goto exit_free_irq;
578 	}
579 
580 	return 0;
581 
582 	exit_free_irq:
583 		free_irq(drv_data->irq, drv_data);
584 	exit_unmap_regs:
585 		mv64xxx_i2c_unmap_regs(drv_data);
586 	exit_kfree:
587 		kfree(drv_data);
588 	return rc;
589 }
590 
591 static int __devexit
592 mv64xxx_i2c_remove(struct platform_device *dev)
593 {
594 	struct mv64xxx_i2c_data		*drv_data = platform_get_drvdata(dev);
595 	int	rc;
596 
597 	rc = i2c_del_adapter(&drv_data->adapter);
598 	free_irq(drv_data->irq, drv_data);
599 	mv64xxx_i2c_unmap_regs(drv_data);
600 	kfree(drv_data);
601 
602 	return rc;
603 }
604 
605 static struct platform_driver mv64xxx_i2c_driver = {
606 	.probe	= mv64xxx_i2c_probe,
607 	.remove	= __devexit_p(mv64xxx_i2c_remove),
608 	.driver	= {
609 		.owner	= THIS_MODULE,
610 		.name	= MV64XXX_I2C_CTLR_NAME,
611 	},
612 };
613 
614 static int __init
615 mv64xxx_i2c_init(void)
616 {
617 	return platform_driver_register(&mv64xxx_i2c_driver);
618 }
619 
620 static void __exit
621 mv64xxx_i2c_exit(void)
622 {
623 	platform_driver_unregister(&mv64xxx_i2c_driver);
624 }
625 
626 module_init(mv64xxx_i2c_init);
627 module_exit(mv64xxx_i2c_exit);
628 
629 MODULE_AUTHOR("Mark A. Greer <mgreer@mvista.com>");
630 MODULE_DESCRIPTION("Marvell mv64xxx host bridge i2c ctlr driver");
631 MODULE_LICENSE("GPL");
632