xref: /linux/drivers/i2c/busses/i2c-mpc.c (revision 5d4a2e29fba5b2bef95b96a46b338ec4d76fa4fd)
1 /*
2  * (C) Copyright 2003-2004
3  * Humboldt Solutions Ltd, adrian@humboldt.co.uk.
4 
5  * This is a combined i2c adapter and algorithm driver for the
6  * MPC107/Tsi107 PowerPC northbridge and processors that include
7  * the same I2C unit (8240, 8245, 85xx).
8  *
9  * Release 0.8
10  *
11  * This file is licensed under the terms of the GNU General Public
12  * License version 2. This program is licensed "as is" without any
13  * warranty of any kind, whether express or implied.
14  */
15 
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/sched.h>
19 #include <linux/init.h>
20 #include <linux/of_platform.h>
21 #include <linux/of_i2c.h>
22 #include <linux/slab.h>
23 
24 #include <linux/io.h>
25 #include <linux/fsl_devices.h>
26 #include <linux/i2c.h>
27 #include <linux/interrupt.h>
28 #include <linux/delay.h>
29 
30 #include <asm/mpc52xx.h>
31 #include <sysdev/fsl_soc.h>
32 
33 #define DRV_NAME "mpc-i2c"
34 
35 #define MPC_I2C_CLOCK_LEGACY   0
36 #define MPC_I2C_CLOCK_PRESERVE (~0U)
37 
38 #define MPC_I2C_FDR   0x04
39 #define MPC_I2C_CR    0x08
40 #define MPC_I2C_SR    0x0c
41 #define MPC_I2C_DR    0x10
42 #define MPC_I2C_DFSRR 0x14
43 
44 #define CCR_MEN  0x80
45 #define CCR_MIEN 0x40
46 #define CCR_MSTA 0x20
47 #define CCR_MTX  0x10
48 #define CCR_TXAK 0x08
49 #define CCR_RSTA 0x04
50 
51 #define CSR_MCF  0x80
52 #define CSR_MAAS 0x40
53 #define CSR_MBB  0x20
54 #define CSR_MAL  0x10
55 #define CSR_SRW  0x04
56 #define CSR_MIF  0x02
57 #define CSR_RXAK 0x01
58 
59 struct mpc_i2c {
60 	struct device *dev;
61 	void __iomem *base;
62 	u32 interrupt;
63 	wait_queue_head_t queue;
64 	struct i2c_adapter adap;
65 	int irq;
66 };
67 
68 struct mpc_i2c_divider {
69 	u16 divider;
70 	u16 fdr;	/* including dfsrr */
71 };
72 
73 struct mpc_i2c_data {
74 	void (*setup)(struct device_node *node, struct mpc_i2c *i2c,
75 		      u32 clock, u32 prescaler);
76 	u32 prescaler;
77 };
78 
79 static inline void writeccr(struct mpc_i2c *i2c, u32 x)
80 {
81 	writeb(x, i2c->base + MPC_I2C_CR);
82 }
83 
84 static irqreturn_t mpc_i2c_isr(int irq, void *dev_id)
85 {
86 	struct mpc_i2c *i2c = dev_id;
87 	if (readb(i2c->base + MPC_I2C_SR) & CSR_MIF) {
88 		/* Read again to allow register to stabilise */
89 		i2c->interrupt = readb(i2c->base + MPC_I2C_SR);
90 		writeb(0, i2c->base + MPC_I2C_SR);
91 		wake_up(&i2c->queue);
92 	}
93 	return IRQ_HANDLED;
94 }
95 
96 /* Sometimes 9th clock pulse isn't generated, and slave doesn't release
97  * the bus, because it wants to send ACK.
98  * Following sequence of enabling/disabling and sending start/stop generates
99  * the pulse, so it's all OK.
100  */
101 static void mpc_i2c_fixup(struct mpc_i2c *i2c)
102 {
103 	writeccr(i2c, 0);
104 	udelay(30);
105 	writeccr(i2c, CCR_MEN);
106 	udelay(30);
107 	writeccr(i2c, CCR_MSTA | CCR_MTX);
108 	udelay(30);
109 	writeccr(i2c, CCR_MSTA | CCR_MTX | CCR_MEN);
110 	udelay(30);
111 	writeccr(i2c, CCR_MEN);
112 	udelay(30);
113 }
114 
115 static int i2c_wait(struct mpc_i2c *i2c, unsigned timeout, int writing)
116 {
117 	unsigned long orig_jiffies = jiffies;
118 	u32 x;
119 	int result = 0;
120 
121 	if (!i2c->irq) {
122 		while (!(readb(i2c->base + MPC_I2C_SR) & CSR_MIF)) {
123 			schedule();
124 			if (time_after(jiffies, orig_jiffies + timeout)) {
125 				dev_dbg(i2c->dev, "timeout\n");
126 				writeccr(i2c, 0);
127 				result = -EIO;
128 				break;
129 			}
130 		}
131 		x = readb(i2c->base + MPC_I2C_SR);
132 		writeb(0, i2c->base + MPC_I2C_SR);
133 	} else {
134 		/* Interrupt mode */
135 		result = wait_event_timeout(i2c->queue,
136 			(i2c->interrupt & CSR_MIF), timeout);
137 
138 		if (unlikely(!(i2c->interrupt & CSR_MIF))) {
139 			dev_dbg(i2c->dev, "wait timeout\n");
140 			writeccr(i2c, 0);
141 			result = -ETIMEDOUT;
142 		}
143 
144 		x = i2c->interrupt;
145 		i2c->interrupt = 0;
146 	}
147 
148 	if (result < 0)
149 		return result;
150 
151 	if (!(x & CSR_MCF)) {
152 		dev_dbg(i2c->dev, "unfinished\n");
153 		return -EIO;
154 	}
155 
156 	if (x & CSR_MAL) {
157 		dev_dbg(i2c->dev, "MAL\n");
158 		return -EIO;
159 	}
160 
161 	if (writing && (x & CSR_RXAK)) {
162 		dev_dbg(i2c->dev, "No RXAK\n");
163 		/* generate stop */
164 		writeccr(i2c, CCR_MEN);
165 		return -EIO;
166 	}
167 	return 0;
168 }
169 
170 #if defined(CONFIG_PPC_MPC52xx) || defined(CONFIG_PPC_MPC512x)
171 static const struct mpc_i2c_divider mpc_i2c_dividers_52xx[] __devinitconst = {
172 	{20, 0x20}, {22, 0x21}, {24, 0x22}, {26, 0x23},
173 	{28, 0x24}, {30, 0x01}, {32, 0x25}, {34, 0x02},
174 	{36, 0x26}, {40, 0x27}, {44, 0x04}, {48, 0x28},
175 	{52, 0x63}, {56, 0x29}, {60, 0x41}, {64, 0x2a},
176 	{68, 0x07}, {72, 0x2b}, {80, 0x2c}, {88, 0x09},
177 	{96, 0x2d}, {104, 0x0a}, {112, 0x2e}, {120, 0x81},
178 	{128, 0x2f}, {136, 0x47}, {144, 0x0c}, {160, 0x30},
179 	{176, 0x49}, {192, 0x31}, {208, 0x4a}, {224, 0x32},
180 	{240, 0x0f}, {256, 0x33}, {272, 0x87}, {288, 0x10},
181 	{320, 0x34}, {352, 0x89}, {384, 0x35}, {416, 0x8a},
182 	{448, 0x36}, {480, 0x13}, {512, 0x37}, {576, 0x14},
183 	{640, 0x38}, {768, 0x39}, {896, 0x3a}, {960, 0x17},
184 	{1024, 0x3b}, {1152, 0x18}, {1280, 0x3c}, {1536, 0x3d},
185 	{1792, 0x3e}, {1920, 0x1b}, {2048, 0x3f}, {2304, 0x1c},
186 	{2560, 0x1d}, {3072, 0x1e}, {3584, 0x7e}, {3840, 0x1f},
187 	{4096, 0x7f}, {4608, 0x5c}, {5120, 0x5d}, {6144, 0x5e},
188 	{7168, 0xbe}, {7680, 0x5f}, {8192, 0xbf}, {9216, 0x9c},
189 	{10240, 0x9d}, {12288, 0x9e}, {15360, 0x9f}
190 };
191 
192 static int __devinit mpc_i2c_get_fdr_52xx(struct device_node *node, u32 clock,
193 					  int prescaler)
194 {
195 	const struct mpc_i2c_divider *div = NULL;
196 	unsigned int pvr = mfspr(SPRN_PVR);
197 	u32 divider;
198 	int i;
199 
200 	if (clock == MPC_I2C_CLOCK_LEGACY)
201 		return -EINVAL;
202 
203 	/* Determine divider value */
204 	divider = mpc5xxx_get_bus_frequency(node) / clock;
205 
206 	/*
207 	 * We want to choose an FDR/DFSR that generates an I2C bus speed that
208 	 * is equal to or lower than the requested speed.
209 	 */
210 	for (i = 0; i < ARRAY_SIZE(mpc_i2c_dividers_52xx); i++) {
211 		div = &mpc_i2c_dividers_52xx[i];
212 		/* Old MPC5200 rev A CPUs do not support the high bits */
213 		if (div->fdr & 0xc0 && pvr == 0x80822011)
214 			continue;
215 		if (div->divider >= divider)
216 			break;
217 	}
218 
219 	return div ? (int)div->fdr : -EINVAL;
220 }
221 
222 static void __devinit mpc_i2c_setup_52xx(struct device_node *node,
223 					 struct mpc_i2c *i2c,
224 					 u32 clock, u32 prescaler)
225 {
226 	int ret, fdr;
227 
228 	if (clock == MPC_I2C_CLOCK_PRESERVE) {
229 		dev_dbg(i2c->dev, "using fdr %d\n",
230 			readb(i2c->base + MPC_I2C_FDR));
231 		return;
232 	}
233 
234 	ret = mpc_i2c_get_fdr_52xx(node, clock, prescaler);
235 	fdr = (ret >= 0) ? ret : 0x3f; /* backward compatibility */
236 
237 	writeb(fdr & 0xff, i2c->base + MPC_I2C_FDR);
238 
239 	if (ret >= 0)
240 		dev_info(i2c->dev, "clock %d Hz (fdr=%d)\n", clock, fdr);
241 }
242 #else /* !(CONFIG_PPC_MPC52xx || CONFIG_PPC_MPC512x) */
243 static void __devinit mpc_i2c_setup_52xx(struct device_node *node,
244 					 struct mpc_i2c *i2c,
245 					 u32 clock, u32 prescaler)
246 {
247 }
248 #endif /* CONFIG_PPC_MPC52xx || CONFIG_PPC_MPC512x */
249 
250 #ifdef CONFIG_PPC_MPC512x
251 static void __devinit mpc_i2c_setup_512x(struct device_node *node,
252 					 struct mpc_i2c *i2c,
253 					 u32 clock, u32 prescaler)
254 {
255 	struct device_node *node_ctrl;
256 	void __iomem *ctrl;
257 	const u32 *pval;
258 	u32 idx;
259 
260 	/* Enable I2C interrupts for mpc5121 */
261 	node_ctrl = of_find_compatible_node(NULL, NULL,
262 					    "fsl,mpc5121-i2c-ctrl");
263 	if (node_ctrl) {
264 		ctrl = of_iomap(node_ctrl, 0);
265 		if (ctrl) {
266 			/* Interrupt enable bits for i2c-0/1/2: bit 24/26/28 */
267 			pval = of_get_property(node, "reg", NULL);
268 			idx = (*pval & 0xff) / 0x20;
269 			setbits32(ctrl, 1 << (24 + idx * 2));
270 			iounmap(ctrl);
271 		}
272 		of_node_put(node_ctrl);
273 	}
274 
275 	/* The clock setup for the 52xx works also fine for the 512x */
276 	mpc_i2c_setup_52xx(node, i2c, clock, prescaler);
277 }
278 #else /* CONFIG_PPC_MPC512x */
279 static void __devinit mpc_i2c_setup_512x(struct device_node *node,
280 					 struct mpc_i2c *i2c,
281 					 u32 clock, u32 prescaler)
282 {
283 }
284 #endif /* CONFIG_PPC_MPC512x */
285 
286 #ifdef CONFIG_FSL_SOC
287 static const struct mpc_i2c_divider mpc_i2c_dividers_8xxx[] __devinitconst = {
288 	{160, 0x0120}, {192, 0x0121}, {224, 0x0122}, {256, 0x0123},
289 	{288, 0x0100}, {320, 0x0101}, {352, 0x0601}, {384, 0x0102},
290 	{416, 0x0602}, {448, 0x0126}, {480, 0x0103}, {512, 0x0127},
291 	{544, 0x0b03}, {576, 0x0104}, {608, 0x1603}, {640, 0x0105},
292 	{672, 0x2003}, {704, 0x0b05}, {736, 0x2b03}, {768, 0x0106},
293 	{800, 0x3603}, {832, 0x0b06}, {896, 0x012a}, {960, 0x0107},
294 	{1024, 0x012b}, {1088, 0x1607}, {1152, 0x0108}, {1216, 0x2b07},
295 	{1280, 0x0109}, {1408, 0x1609}, {1536, 0x010a}, {1664, 0x160a},
296 	{1792, 0x012e}, {1920, 0x010b}, {2048, 0x012f}, {2176, 0x2b0b},
297 	{2304, 0x010c}, {2560, 0x010d}, {2816, 0x2b0d}, {3072, 0x010e},
298 	{3328, 0x2b0e}, {3584, 0x0132}, {3840, 0x010f}, {4096, 0x0133},
299 	{4608, 0x0110}, {5120, 0x0111}, {6144, 0x0112}, {7168, 0x0136},
300 	{7680, 0x0113}, {8192, 0x0137}, {9216, 0x0114}, {10240, 0x0115},
301 	{12288, 0x0116}, {14336, 0x013a}, {15360, 0x0117}, {16384, 0x013b},
302 	{18432, 0x0118}, {20480, 0x0119}, {24576, 0x011a}, {28672, 0x013e},
303 	{30720, 0x011b}, {32768, 0x013f}, {36864, 0x011c}, {40960, 0x011d},
304 	{49152, 0x011e}, {61440, 0x011f}
305 };
306 
307 static u32 __devinit mpc_i2c_get_sec_cfg_8xxx(void)
308 {
309 	struct device_node *node = NULL;
310 	u32 __iomem *reg;
311 	u32 val = 0;
312 
313 	node = of_find_node_by_name(NULL, "global-utilities");
314 	if (node) {
315 		const u32 *prop = of_get_property(node, "reg", NULL);
316 		if (prop) {
317 			/*
318 			 * Map and check POR Device Status Register 2
319 			 * (PORDEVSR2) at 0xE0014
320 			 */
321 			reg = ioremap(get_immrbase() + *prop + 0x14, 0x4);
322 			if (!reg)
323 				printk(KERN_ERR
324 				       "Error: couldn't map PORDEVSR2\n");
325 			else
326 				val = in_be32(reg) & 0x00000080; /* sec-cfg */
327 			iounmap(reg);
328 		}
329 	}
330 	if (node)
331 		of_node_put(node);
332 
333 	return val;
334 }
335 
336 static int __devinit mpc_i2c_get_fdr_8xxx(struct device_node *node, u32 clock,
337 					  u32 prescaler)
338 {
339 	const struct mpc_i2c_divider *div = NULL;
340 	u32 divider;
341 	int i;
342 
343 	if (clock == MPC_I2C_CLOCK_LEGACY)
344 		return -EINVAL;
345 
346 	/* Determine proper divider value */
347 	if (of_device_is_compatible(node, "fsl,mpc8544-i2c"))
348 		prescaler = mpc_i2c_get_sec_cfg_8xxx() ? 3 : 2;
349 	if (!prescaler)
350 		prescaler = 1;
351 
352 	divider = fsl_get_sys_freq() / clock / prescaler;
353 
354 	pr_debug("I2C: src_clock=%d clock=%d divider=%d\n",
355 		 fsl_get_sys_freq(), clock, divider);
356 
357 	/*
358 	 * We want to choose an FDR/DFSR that generates an I2C bus speed that
359 	 * is equal to or lower than the requested speed.
360 	 */
361 	for (i = 0; i < ARRAY_SIZE(mpc_i2c_dividers_8xxx); i++) {
362 		div = &mpc_i2c_dividers_8xxx[i];
363 		if (div->divider >= divider)
364 			break;
365 	}
366 
367 	return div ? (int)div->fdr : -EINVAL;
368 }
369 
370 static void __devinit mpc_i2c_setup_8xxx(struct device_node *node,
371 					 struct mpc_i2c *i2c,
372 					 u32 clock, u32 prescaler)
373 {
374 	int ret, fdr;
375 
376 	if (clock == MPC_I2C_CLOCK_PRESERVE) {
377 		dev_dbg(i2c->dev, "using dfsrr %d, fdr %d\n",
378 			readb(i2c->base + MPC_I2C_DFSRR),
379 			readb(i2c->base + MPC_I2C_FDR));
380 		return;
381 	}
382 
383 	ret = mpc_i2c_get_fdr_8xxx(node, clock, prescaler);
384 	fdr = (ret >= 0) ? ret : 0x1031; /* backward compatibility */
385 
386 	writeb(fdr & 0xff, i2c->base + MPC_I2C_FDR);
387 	writeb((fdr >> 8) & 0xff, i2c->base + MPC_I2C_DFSRR);
388 
389 	if (ret >= 0)
390 		dev_info(i2c->dev, "clock %d Hz (dfsrr=%d fdr=%d)\n",
391 			 clock, fdr >> 8, fdr & 0xff);
392 }
393 
394 #else /* !CONFIG_FSL_SOC */
395 static void __devinit mpc_i2c_setup_8xxx(struct device_node *node,
396 					 struct mpc_i2c *i2c,
397 					 u32 clock, u32 prescaler)
398 {
399 }
400 #endif /* CONFIG_FSL_SOC */
401 
402 static void mpc_i2c_start(struct mpc_i2c *i2c)
403 {
404 	/* Clear arbitration */
405 	writeb(0, i2c->base + MPC_I2C_SR);
406 	/* Start with MEN */
407 	writeccr(i2c, CCR_MEN);
408 }
409 
410 static void mpc_i2c_stop(struct mpc_i2c *i2c)
411 {
412 	writeccr(i2c, CCR_MEN);
413 }
414 
415 static int mpc_write(struct mpc_i2c *i2c, int target,
416 		     const u8 *data, int length, int restart)
417 {
418 	int i, result;
419 	unsigned timeout = i2c->adap.timeout;
420 	u32 flags = restart ? CCR_RSTA : 0;
421 
422 	/* Start as master */
423 	writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_MTX | flags);
424 	/* Write target byte */
425 	writeb((target << 1), i2c->base + MPC_I2C_DR);
426 
427 	result = i2c_wait(i2c, timeout, 1);
428 	if (result < 0)
429 		return result;
430 
431 	for (i = 0; i < length; i++) {
432 		/* Write data byte */
433 		writeb(data[i], i2c->base + MPC_I2C_DR);
434 
435 		result = i2c_wait(i2c, timeout, 1);
436 		if (result < 0)
437 			return result;
438 	}
439 
440 	return 0;
441 }
442 
443 static int mpc_read(struct mpc_i2c *i2c, int target,
444 		    u8 *data, int length, int restart)
445 {
446 	unsigned timeout = i2c->adap.timeout;
447 	int i, result;
448 	u32 flags = restart ? CCR_RSTA : 0;
449 
450 	/* Switch to read - restart */
451 	writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_MTX | flags);
452 	/* Write target address byte - this time with the read flag set */
453 	writeb((target << 1) | 1, i2c->base + MPC_I2C_DR);
454 
455 	result = i2c_wait(i2c, timeout, 1);
456 	if (result < 0)
457 		return result;
458 
459 	if (length) {
460 		if (length == 1)
461 			writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_TXAK);
462 		else
463 			writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA);
464 		/* Dummy read */
465 		readb(i2c->base + MPC_I2C_DR);
466 	}
467 
468 	for (i = 0; i < length; i++) {
469 		result = i2c_wait(i2c, timeout, 0);
470 		if (result < 0)
471 			return result;
472 
473 		/* Generate txack on next to last byte */
474 		if (i == length - 2)
475 			writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_TXAK);
476 		/* Do not generate stop on last byte */
477 		if (i == length - 1)
478 			writeccr(i2c, CCR_MIEN | CCR_MEN | CCR_MSTA | CCR_MTX);
479 		data[i] = readb(i2c->base + MPC_I2C_DR);
480 	}
481 
482 	return length;
483 }
484 
485 static int mpc_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
486 {
487 	struct i2c_msg *pmsg;
488 	int i;
489 	int ret = 0;
490 	unsigned long orig_jiffies = jiffies;
491 	struct mpc_i2c *i2c = i2c_get_adapdata(adap);
492 
493 	mpc_i2c_start(i2c);
494 
495 	/* Allow bus up to 1s to become not busy */
496 	while (readb(i2c->base + MPC_I2C_SR) & CSR_MBB) {
497 		if (signal_pending(current)) {
498 			dev_dbg(i2c->dev, "Interrupted\n");
499 			writeccr(i2c, 0);
500 			return -EINTR;
501 		}
502 		if (time_after(jiffies, orig_jiffies + HZ)) {
503 			dev_dbg(i2c->dev, "timeout\n");
504 			if (readb(i2c->base + MPC_I2C_SR) ==
505 			    (CSR_MCF | CSR_MBB | CSR_RXAK))
506 				mpc_i2c_fixup(i2c);
507 			return -EIO;
508 		}
509 		schedule();
510 	}
511 
512 	for (i = 0; ret >= 0 && i < num; i++) {
513 		pmsg = &msgs[i];
514 		dev_dbg(i2c->dev,
515 			"Doing %s %d bytes to 0x%02x - %d of %d messages\n",
516 			pmsg->flags & I2C_M_RD ? "read" : "write",
517 			pmsg->len, pmsg->addr, i + 1, num);
518 		if (pmsg->flags & I2C_M_RD)
519 			ret =
520 			    mpc_read(i2c, pmsg->addr, pmsg->buf, pmsg->len, i);
521 		else
522 			ret =
523 			    mpc_write(i2c, pmsg->addr, pmsg->buf, pmsg->len, i);
524 	}
525 	mpc_i2c_stop(i2c);
526 	return (ret < 0) ? ret : num;
527 }
528 
529 static u32 mpc_functionality(struct i2c_adapter *adap)
530 {
531 	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
532 }
533 
534 static const struct i2c_algorithm mpc_algo = {
535 	.master_xfer = mpc_xfer,
536 	.functionality = mpc_functionality,
537 };
538 
539 static struct i2c_adapter mpc_ops = {
540 	.owner = THIS_MODULE,
541 	.name = "MPC adapter",
542 	.algo = &mpc_algo,
543 	.timeout = HZ,
544 };
545 
546 static int __devinit fsl_i2c_probe(struct of_device *op,
547 				   const struct of_device_id *match)
548 {
549 	struct mpc_i2c *i2c;
550 	const u32 *prop;
551 	u32 clock = MPC_I2C_CLOCK_LEGACY;
552 	int result = 0;
553 	int plen;
554 
555 	i2c = kzalloc(sizeof(*i2c), GFP_KERNEL);
556 	if (!i2c)
557 		return -ENOMEM;
558 
559 	i2c->dev = &op->dev; /* for debug and error output */
560 
561 	init_waitqueue_head(&i2c->queue);
562 
563 	i2c->base = of_iomap(op->dev.of_node, 0);
564 	if (!i2c->base) {
565 		dev_err(i2c->dev, "failed to map controller\n");
566 		result = -ENOMEM;
567 		goto fail_map;
568 	}
569 
570 	i2c->irq = irq_of_parse_and_map(op->dev.of_node, 0);
571 	if (i2c->irq) { /* no i2c->irq implies polling */
572 		result = request_irq(i2c->irq, mpc_i2c_isr,
573 				     IRQF_SHARED, "i2c-mpc", i2c);
574 		if (result < 0) {
575 			dev_err(i2c->dev, "failed to attach interrupt\n");
576 			goto fail_request;
577 		}
578 	}
579 
580 	if (of_get_property(op->dev.of_node, "fsl,preserve-clocking", NULL)) {
581 		clock = MPC_I2C_CLOCK_PRESERVE;
582 	} else {
583 		prop = of_get_property(op->dev.of_node, "clock-frequency",
584 					&plen);
585 		if (prop && plen == sizeof(u32))
586 			clock = *prop;
587 	}
588 
589 	if (match->data) {
590 		struct mpc_i2c_data *data = match->data;
591 		data->setup(op->dev.of_node, i2c, clock, data->prescaler);
592 	} else {
593 		/* Backwards compatibility */
594 		if (of_get_property(op->dev.of_node, "dfsrr", NULL))
595 			mpc_i2c_setup_8xxx(op->dev.of_node, i2c, clock, 0);
596 	}
597 
598 	dev_set_drvdata(&op->dev, i2c);
599 
600 	i2c->adap = mpc_ops;
601 	i2c_set_adapdata(&i2c->adap, i2c);
602 	i2c->adap.dev.parent = &op->dev;
603 
604 	result = i2c_add_adapter(&i2c->adap);
605 	if (result < 0) {
606 		dev_err(i2c->dev, "failed to add adapter\n");
607 		goto fail_add;
608 	}
609 	of_register_i2c_devices(&i2c->adap, op->dev.of_node);
610 
611 	return result;
612 
613  fail_add:
614 	dev_set_drvdata(&op->dev, NULL);
615 	free_irq(i2c->irq, i2c);
616  fail_request:
617 	irq_dispose_mapping(i2c->irq);
618 	iounmap(i2c->base);
619  fail_map:
620 	kfree(i2c);
621 	return result;
622 };
623 
624 static int __devexit fsl_i2c_remove(struct of_device *op)
625 {
626 	struct mpc_i2c *i2c = dev_get_drvdata(&op->dev);
627 
628 	i2c_del_adapter(&i2c->adap);
629 	dev_set_drvdata(&op->dev, NULL);
630 
631 	if (i2c->irq)
632 		free_irq(i2c->irq, i2c);
633 
634 	irq_dispose_mapping(i2c->irq);
635 	iounmap(i2c->base);
636 	kfree(i2c);
637 	return 0;
638 };
639 
640 static struct mpc_i2c_data mpc_i2c_data_512x __devinitdata = {
641 	.setup = mpc_i2c_setup_512x,
642 };
643 
644 static struct mpc_i2c_data mpc_i2c_data_52xx __devinitdata = {
645 	.setup = mpc_i2c_setup_52xx,
646 };
647 
648 static struct mpc_i2c_data mpc_i2c_data_8313 __devinitdata = {
649 	.setup = mpc_i2c_setup_8xxx,
650 };
651 
652 static struct mpc_i2c_data mpc_i2c_data_8543 __devinitdata = {
653 	.setup = mpc_i2c_setup_8xxx,
654 	.prescaler = 2,
655 };
656 
657 static struct mpc_i2c_data mpc_i2c_data_8544 __devinitdata = {
658 	.setup = mpc_i2c_setup_8xxx,
659 	.prescaler = 3,
660 };
661 
662 static const struct of_device_id mpc_i2c_of_match[] = {
663 	{.compatible = "mpc5200-i2c", .data = &mpc_i2c_data_52xx, },
664 	{.compatible = "fsl,mpc5200b-i2c", .data = &mpc_i2c_data_52xx, },
665 	{.compatible = "fsl,mpc5200-i2c", .data = &mpc_i2c_data_52xx, },
666 	{.compatible = "fsl,mpc5121-i2c", .data = &mpc_i2c_data_512x, },
667 	{.compatible = "fsl,mpc8313-i2c", .data = &mpc_i2c_data_8313, },
668 	{.compatible = "fsl,mpc8543-i2c", .data = &mpc_i2c_data_8543, },
669 	{.compatible = "fsl,mpc8544-i2c", .data = &mpc_i2c_data_8544, },
670 	/* Backward compatibility */
671 	{.compatible = "fsl-i2c", },
672 	{},
673 };
674 MODULE_DEVICE_TABLE(of, mpc_i2c_of_match);
675 
676 /* Structure for a device driver */
677 static struct of_platform_driver mpc_i2c_driver = {
678 	.probe		= fsl_i2c_probe,
679 	.remove		= __devexit_p(fsl_i2c_remove),
680 	.driver = {
681 		.owner = THIS_MODULE,
682 		.name = DRV_NAME,
683 		.of_match_table = mpc_i2c_of_match,
684 	},
685 };
686 
687 static int __init fsl_i2c_init(void)
688 {
689 	int rv;
690 
691 	rv = of_register_platform_driver(&mpc_i2c_driver);
692 	if (rv)
693 		printk(KERN_ERR DRV_NAME
694 		       " of_register_platform_driver failed (%i)\n", rv);
695 	return rv;
696 }
697 
698 static void __exit fsl_i2c_exit(void)
699 {
700 	of_unregister_platform_driver(&mpc_i2c_driver);
701 }
702 
703 module_init(fsl_i2c_init);
704 module_exit(fsl_i2c_exit);
705 
706 MODULE_AUTHOR("Adrian Cox <adrian@humboldt.co.uk>");
707 MODULE_DESCRIPTION("I2C-Bus adapter for MPC107 bridge and "
708 		   "MPC824x/83xx/85xx/86xx/512x/52xx processors");
709 MODULE_LICENSE("GPL");
710