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Merge remote-tracking branches 'spi/topic/spidev-test', 'spi/topic/ti-qspi', 'spi...
[deliverable/linux.git] / drivers / i2c / busses / i2c-cpm.c
1 /*
2 * Freescale CPM1/CPM2 I2C interface.
3 * Copyright (c) 1999 Dan Malek (dmalek@jlc.net).
4 *
5 * moved into proper i2c interface;
6 * Brad Parker (brad@heeltoe.com)
7 *
8 * Parts from dbox2_i2c.c (cvs.tuxbox.org)
9 * (C) 2000-2001 Felix Domke (tmbinc@gmx.net), Gillem (htoa@gmx.net)
10 *
11 * (C) 2007 Montavista Software, Inc.
12 * Vitaly Bordug <vitb@kernel.crashing.org>
13 *
14 * Converted to of_platform_device. Renamed to i2c-cpm.c.
15 * (C) 2007,2008 Jochen Friedrich <jochen@scram.de>
16 *
17 * This program is free software; you can redistribute it and/or modify
18 * it under the terms of the GNU General Public License as published by
19 * the Free Software Foundation; either version 2 of the License, or
20 * (at your option) any later version.
21 *
22 * This program is distributed in the hope that it will be useful,
23 * but WITHOUT ANY WARRANTY; without even the implied warranty of
24 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
25 * GNU General Public License for more details.
26 */
27
28 #include <linux/kernel.h>
29 #include <linux/module.h>
30 #include <linux/delay.h>
31 #include <linux/slab.h>
32 #include <linux/interrupt.h>
33 #include <linux/errno.h>
34 #include <linux/stddef.h>
35 #include <linux/i2c.h>
36 #include <linux/io.h>
37 #include <linux/dma-mapping.h>
38 #include <linux/of_address.h>
39 #include <linux/of_device.h>
40 #include <linux/of_irq.h>
41 #include <linux/of_platform.h>
42 #include <sysdev/fsl_soc.h>
43 #include <asm/cpm.h>
44
45 /* Try to define this if you have an older CPU (earlier than rev D4) */
46 /* However, better use a GPIO based bitbang driver in this case :/ */
47 #undef I2C_CHIP_ERRATA
48
49 #define CPM_MAX_READ 513
50 #define CPM_MAXBD 4
51
52 #define I2C_EB (0x10) /* Big endian mode */
53 #define I2C_EB_CPM2 (0x30) /* Big endian mode, memory snoop */
54
55 #define DPRAM_BASE ((u8 __iomem __force *)cpm_muram_addr(0))
56
57 /* I2C parameter RAM. */
58 struct i2c_ram {
59 ushort rbase; /* Rx Buffer descriptor base address */
60 ushort tbase; /* Tx Buffer descriptor base address */
61 u_char rfcr; /* Rx function code */
62 u_char tfcr; /* Tx function code */
63 ushort mrblr; /* Max receive buffer length */
64 uint rstate; /* Internal */
65 uint rdp; /* Internal */
66 ushort rbptr; /* Rx Buffer descriptor pointer */
67 ushort rbc; /* Internal */
68 uint rxtmp; /* Internal */
69 uint tstate; /* Internal */
70 uint tdp; /* Internal */
71 ushort tbptr; /* Tx Buffer descriptor pointer */
72 ushort tbc; /* Internal */
73 uint txtmp; /* Internal */
74 char res1[4]; /* Reserved */
75 ushort rpbase; /* Relocation pointer */
76 char res2[2]; /* Reserved */
77 };
78
79 #define I2COM_START 0x80
80 #define I2COM_MASTER 0x01
81 #define I2CER_TXE 0x10
82 #define I2CER_BUSY 0x04
83 #define I2CER_TXB 0x02
84 #define I2CER_RXB 0x01
85 #define I2MOD_EN 0x01
86
87 /* I2C Registers */
88 struct i2c_reg {
89 u8 i2mod;
90 u8 res1[3];
91 u8 i2add;
92 u8 res2[3];
93 u8 i2brg;
94 u8 res3[3];
95 u8 i2com;
96 u8 res4[3];
97 u8 i2cer;
98 u8 res5[3];
99 u8 i2cmr;
100 };
101
102 struct cpm_i2c {
103 char *base;
104 struct platform_device *ofdev;
105 struct i2c_adapter adap;
106 uint dp_addr;
107 int version; /* CPM1=1, CPM2=2 */
108 int irq;
109 int cp_command;
110 int freq;
111 struct i2c_reg __iomem *i2c_reg;
112 struct i2c_ram __iomem *i2c_ram;
113 u16 i2c_addr;
114 wait_queue_head_t i2c_wait;
115 cbd_t __iomem *tbase;
116 cbd_t __iomem *rbase;
117 u_char *txbuf[CPM_MAXBD];
118 u_char *rxbuf[CPM_MAXBD];
119 dma_addr_t txdma[CPM_MAXBD];
120 dma_addr_t rxdma[CPM_MAXBD];
121 };
122
123 static irqreturn_t cpm_i2c_interrupt(int irq, void *dev_id)
124 {
125 struct cpm_i2c *cpm;
126 struct i2c_reg __iomem *i2c_reg;
127 struct i2c_adapter *adap = dev_id;
128 int i;
129
130 cpm = i2c_get_adapdata(dev_id);
131 i2c_reg = cpm->i2c_reg;
132
133 /* Clear interrupt. */
134 i = in_8(&i2c_reg->i2cer);
135 out_8(&i2c_reg->i2cer, i);
136
137 dev_dbg(&adap->dev, "Interrupt: %x\n", i);
138
139 wake_up(&cpm->i2c_wait);
140
141 return i ? IRQ_HANDLED : IRQ_NONE;
142 }
143
144 static void cpm_reset_i2c_params(struct cpm_i2c *cpm)
145 {
146 struct i2c_ram __iomem *i2c_ram = cpm->i2c_ram;
147
148 /* Set up the I2C parameters in the parameter ram. */
149 out_be16(&i2c_ram->tbase, (u8 __iomem *)cpm->tbase - DPRAM_BASE);
150 out_be16(&i2c_ram->rbase, (u8 __iomem *)cpm->rbase - DPRAM_BASE);
151
152 if (cpm->version == 1) {
153 out_8(&i2c_ram->tfcr, I2C_EB);
154 out_8(&i2c_ram->rfcr, I2C_EB);
155 } else {
156 out_8(&i2c_ram->tfcr, I2C_EB_CPM2);
157 out_8(&i2c_ram->rfcr, I2C_EB_CPM2);
158 }
159
160 out_be16(&i2c_ram->mrblr, CPM_MAX_READ);
161
162 out_be32(&i2c_ram->rstate, 0);
163 out_be32(&i2c_ram->rdp, 0);
164 out_be16(&i2c_ram->rbptr, 0);
165 out_be16(&i2c_ram->rbc, 0);
166 out_be32(&i2c_ram->rxtmp, 0);
167 out_be32(&i2c_ram->tstate, 0);
168 out_be32(&i2c_ram->tdp, 0);
169 out_be16(&i2c_ram->tbptr, 0);
170 out_be16(&i2c_ram->tbc, 0);
171 out_be32(&i2c_ram->txtmp, 0);
172 }
173
174 static void cpm_i2c_force_close(struct i2c_adapter *adap)
175 {
176 struct cpm_i2c *cpm = i2c_get_adapdata(adap);
177 struct i2c_reg __iomem *i2c_reg = cpm->i2c_reg;
178
179 dev_dbg(&adap->dev, "cpm_i2c_force_close()\n");
180
181 cpm_command(cpm->cp_command, CPM_CR_CLOSE_RX_BD);
182
183 out_8(&i2c_reg->i2cmr, 0x00); /* Disable all interrupts */
184 out_8(&i2c_reg->i2cer, 0xff);
185 }
186
187 static void cpm_i2c_parse_message(struct i2c_adapter *adap,
188 struct i2c_msg *pmsg, int num, int tx, int rx)
189 {
190 cbd_t __iomem *tbdf;
191 cbd_t __iomem *rbdf;
192 u_char addr;
193 u_char *tb;
194 u_char *rb;
195 struct cpm_i2c *cpm = i2c_get_adapdata(adap);
196
197 tbdf = cpm->tbase + tx;
198 rbdf = cpm->rbase + rx;
199
200 addr = i2c_8bit_addr_from_msg(pmsg);
201
202 tb = cpm->txbuf[tx];
203 rb = cpm->rxbuf[rx];
204
205 /* Align read buffer */
206 rb = (u_char *) (((ulong) rb + 1) & ~1);
207
208 tb[0] = addr; /* Device address byte w/rw flag */
209
210 out_be16(&tbdf->cbd_datlen, pmsg->len + 1);
211 out_be16(&tbdf->cbd_sc, 0);
212
213 if (!(pmsg->flags & I2C_M_NOSTART))
214 setbits16(&tbdf->cbd_sc, BD_I2C_START);
215
216 if (tx + 1 == num)
217 setbits16(&tbdf->cbd_sc, BD_SC_LAST | BD_SC_WRAP);
218
219 if (pmsg->flags & I2C_M_RD) {
220 /*
221 * To read, we need an empty buffer of the proper length.
222 * All that is used is the first byte for address, the remainder
223 * is just used for timing (and doesn't really have to exist).
224 */
225
226 dev_dbg(&adap->dev, "cpm_i2c_read(abyte=0x%x)\n", addr);
227
228 out_be16(&rbdf->cbd_datlen, 0);
229 out_be16(&rbdf->cbd_sc, BD_SC_EMPTY | BD_SC_INTRPT);
230
231 if (rx + 1 == CPM_MAXBD)
232 setbits16(&rbdf->cbd_sc, BD_SC_WRAP);
233
234 eieio();
235 setbits16(&tbdf->cbd_sc, BD_SC_READY);
236 } else {
237 dev_dbg(&adap->dev, "cpm_i2c_write(abyte=0x%x)\n", addr);
238
239 memcpy(tb+1, pmsg->buf, pmsg->len);
240
241 eieio();
242 setbits16(&tbdf->cbd_sc, BD_SC_READY | BD_SC_INTRPT);
243 }
244 }
245
246 static int cpm_i2c_check_message(struct i2c_adapter *adap,
247 struct i2c_msg *pmsg, int tx, int rx)
248 {
249 cbd_t __iomem *tbdf;
250 cbd_t __iomem *rbdf;
251 u_char *tb;
252 u_char *rb;
253 struct cpm_i2c *cpm = i2c_get_adapdata(adap);
254
255 tbdf = cpm->tbase + tx;
256 rbdf = cpm->rbase + rx;
257
258 tb = cpm->txbuf[tx];
259 rb = cpm->rxbuf[rx];
260
261 /* Align read buffer */
262 rb = (u_char *) (((uint) rb + 1) & ~1);
263
264 eieio();
265 if (pmsg->flags & I2C_M_RD) {
266 dev_dbg(&adap->dev, "tx sc 0x%04x, rx sc 0x%04x\n",
267 in_be16(&tbdf->cbd_sc), in_be16(&rbdf->cbd_sc));
268
269 if (in_be16(&tbdf->cbd_sc) & BD_SC_NAK) {
270 dev_dbg(&adap->dev, "I2C read; No ack\n");
271 return -ENXIO;
272 }
273 if (in_be16(&rbdf->cbd_sc) & BD_SC_EMPTY) {
274 dev_err(&adap->dev,
275 "I2C read; complete but rbuf empty\n");
276 return -EREMOTEIO;
277 }
278 if (in_be16(&rbdf->cbd_sc) & BD_SC_OV) {
279 dev_err(&adap->dev, "I2C read; Overrun\n");
280 return -EREMOTEIO;
281 }
282 memcpy(pmsg->buf, rb, pmsg->len);
283 } else {
284 dev_dbg(&adap->dev, "tx sc %d 0x%04x\n", tx,
285 in_be16(&tbdf->cbd_sc));
286
287 if (in_be16(&tbdf->cbd_sc) & BD_SC_NAK) {
288 dev_dbg(&adap->dev, "I2C write; No ack\n");
289 return -ENXIO;
290 }
291 if (in_be16(&tbdf->cbd_sc) & BD_SC_UN) {
292 dev_err(&adap->dev, "I2C write; Underrun\n");
293 return -EIO;
294 }
295 if (in_be16(&tbdf->cbd_sc) & BD_SC_CL) {
296 dev_err(&adap->dev, "I2C write; Collision\n");
297 return -EIO;
298 }
299 }
300 return 0;
301 }
302
303 static int cpm_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
304 {
305 struct cpm_i2c *cpm = i2c_get_adapdata(adap);
306 struct i2c_reg __iomem *i2c_reg = cpm->i2c_reg;
307 struct i2c_ram __iomem *i2c_ram = cpm->i2c_ram;
308 struct i2c_msg *pmsg;
309 int ret;
310 int tptr;
311 int rptr;
312 cbd_t __iomem *tbdf;
313 cbd_t __iomem *rbdf;
314
315 /* Reset to use first buffer */
316 out_be16(&i2c_ram->rbptr, in_be16(&i2c_ram->rbase));
317 out_be16(&i2c_ram->tbptr, in_be16(&i2c_ram->tbase));
318
319 tbdf = cpm->tbase;
320 rbdf = cpm->rbase;
321
322 tptr = 0;
323 rptr = 0;
324
325 /*
326 * If there was a collision in the last i2c transaction,
327 * Set I2COM_MASTER as it was cleared during collision.
328 */
329 if (in_be16(&tbdf->cbd_sc) & BD_SC_CL) {
330 out_8(&cpm->i2c_reg->i2com, I2COM_MASTER);
331 }
332
333 while (tptr < num) {
334 pmsg = &msgs[tptr];
335 dev_dbg(&adap->dev, "R: %d T: %d\n", rptr, tptr);
336
337 cpm_i2c_parse_message(adap, pmsg, num, tptr, rptr);
338 if (pmsg->flags & I2C_M_RD)
339 rptr++;
340 tptr++;
341 }
342 /* Start transfer now */
343 /* Enable RX/TX/Error interupts */
344 out_8(&i2c_reg->i2cmr, I2CER_TXE | I2CER_TXB | I2CER_RXB);
345 out_8(&i2c_reg->i2cer, 0xff); /* Clear interrupt status */
346 /* Chip bug, set enable here */
347 setbits8(&i2c_reg->i2mod, I2MOD_EN); /* Enable */
348 /* Begin transmission */
349 setbits8(&i2c_reg->i2com, I2COM_START);
350
351 tptr = 0;
352 rptr = 0;
353
354 while (tptr < num) {
355 /* Check for outstanding messages */
356 dev_dbg(&adap->dev, "test ready.\n");
357 pmsg = &msgs[tptr];
358 if (pmsg->flags & I2C_M_RD)
359 ret = wait_event_timeout(cpm->i2c_wait,
360 (in_be16(&tbdf[tptr].cbd_sc) & BD_SC_NAK) ||
361 !(in_be16(&rbdf[rptr].cbd_sc) & BD_SC_EMPTY),
362 1 * HZ);
363 else
364 ret = wait_event_timeout(cpm->i2c_wait,
365 !(in_be16(&tbdf[tptr].cbd_sc) & BD_SC_READY),
366 1 * HZ);
367 if (ret == 0) {
368 ret = -EREMOTEIO;
369 dev_err(&adap->dev, "I2C transfer: timeout\n");
370 goto out_err;
371 }
372 if (ret > 0) {
373 dev_dbg(&adap->dev, "ready.\n");
374 ret = cpm_i2c_check_message(adap, pmsg, tptr, rptr);
375 tptr++;
376 if (pmsg->flags & I2C_M_RD)
377 rptr++;
378 if (ret)
379 goto out_err;
380 }
381 }
382 #ifdef I2C_CHIP_ERRATA
383 /*
384 * Chip errata, clear enable. This is not needed on rev D4 CPUs.
385 * Disabling I2C too early may cause too short stop condition
386 */
387 udelay(4);
388 clrbits8(&i2c_reg->i2mod, I2MOD_EN);
389 #endif
390 return (num);
391
392 out_err:
393 cpm_i2c_force_close(adap);
394 #ifdef I2C_CHIP_ERRATA
395 /*
396 * Chip errata, clear enable. This is not needed on rev D4 CPUs.
397 */
398 clrbits8(&i2c_reg->i2mod, I2MOD_EN);
399 #endif
400 return ret;
401 }
402
403 static u32 cpm_i2c_func(struct i2c_adapter *adap)
404 {
405 return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
406 }
407
408 /* -----exported algorithm data: ------------------------------------- */
409
410 static const struct i2c_algorithm cpm_i2c_algo = {
411 .master_xfer = cpm_i2c_xfer,
412 .functionality = cpm_i2c_func,
413 };
414
415 /* CPM_MAX_READ is also limiting writes according to the code! */
416 static struct i2c_adapter_quirks cpm_i2c_quirks = {
417 .max_num_msgs = CPM_MAXBD,
418 .max_read_len = CPM_MAX_READ,
419 .max_write_len = CPM_MAX_READ,
420 };
421
422 static const struct i2c_adapter cpm_ops = {
423 .owner = THIS_MODULE,
424 .name = "i2c-cpm",
425 .algo = &cpm_i2c_algo,
426 .quirks = &cpm_i2c_quirks,
427 };
428
429 static int cpm_i2c_setup(struct cpm_i2c *cpm)
430 {
431 struct platform_device *ofdev = cpm->ofdev;
432 const u32 *data;
433 int len, ret, i;
434 void __iomem *i2c_base;
435 cbd_t __iomem *tbdf;
436 cbd_t __iomem *rbdf;
437 unsigned char brg;
438
439 dev_dbg(&cpm->ofdev->dev, "cpm_i2c_setup()\n");
440
441 init_waitqueue_head(&cpm->i2c_wait);
442
443 cpm->irq = irq_of_parse_and_map(ofdev->dev.of_node, 0);
444 if (!cpm->irq)
445 return -EINVAL;
446
447 /* Install interrupt handler. */
448 ret = request_irq(cpm->irq, cpm_i2c_interrupt, 0, "cpm_i2c",
449 &cpm->adap);
450 if (ret)
451 return ret;
452
453 /* I2C parameter RAM */
454 i2c_base = of_iomap(ofdev->dev.of_node, 1);
455 if (i2c_base == NULL) {
456 ret = -EINVAL;
457 goto out_irq;
458 }
459
460 if (of_device_is_compatible(ofdev->dev.of_node, "fsl,cpm1-i2c")) {
461
462 /* Check for and use a microcode relocation patch. */
463 cpm->i2c_ram = i2c_base;
464 cpm->i2c_addr = in_be16(&cpm->i2c_ram->rpbase);
465
466 /*
467 * Maybe should use cpm_muram_alloc instead of hardcoding
468 * this in micropatch.c
469 */
470 if (cpm->i2c_addr) {
471 cpm->i2c_ram = cpm_muram_addr(cpm->i2c_addr);
472 iounmap(i2c_base);
473 }
474
475 cpm->version = 1;
476
477 } else if (of_device_is_compatible(ofdev->dev.of_node, "fsl,cpm2-i2c")) {
478 cpm->i2c_addr = cpm_muram_alloc(sizeof(struct i2c_ram), 64);
479 cpm->i2c_ram = cpm_muram_addr(cpm->i2c_addr);
480 out_be16(i2c_base, cpm->i2c_addr);
481 iounmap(i2c_base);
482
483 cpm->version = 2;
484
485 } else {
486 iounmap(i2c_base);
487 ret = -EINVAL;
488 goto out_irq;
489 }
490
491 /* I2C control/status registers */
492 cpm->i2c_reg = of_iomap(ofdev->dev.of_node, 0);
493 if (cpm->i2c_reg == NULL) {
494 ret = -EINVAL;
495 goto out_ram;
496 }
497
498 data = of_get_property(ofdev->dev.of_node, "fsl,cpm-command", &len);
499 if (!data || len != 4) {
500 ret = -EINVAL;
501 goto out_reg;
502 }
503 cpm->cp_command = *data;
504
505 data = of_get_property(ofdev->dev.of_node, "linux,i2c-class", &len);
506 if (data && len == 4)
507 cpm->adap.class = *data;
508
509 data = of_get_property(ofdev->dev.of_node, "clock-frequency", &len);
510 if (data && len == 4)
511 cpm->freq = *data;
512 else
513 cpm->freq = 60000; /* use 60kHz i2c clock by default */
514
515 /*
516 * Allocate space for CPM_MAXBD transmit and receive buffer
517 * descriptors in the DP ram.
518 */
519 cpm->dp_addr = cpm_muram_alloc(sizeof(cbd_t) * 2 * CPM_MAXBD, 8);
520 if (!cpm->dp_addr) {
521 ret = -ENOMEM;
522 goto out_reg;
523 }
524
525 cpm->tbase = cpm_muram_addr(cpm->dp_addr);
526 cpm->rbase = cpm_muram_addr(cpm->dp_addr + sizeof(cbd_t) * CPM_MAXBD);
527
528 /* Allocate TX and RX buffers */
529
530 tbdf = cpm->tbase;
531 rbdf = cpm->rbase;
532
533 for (i = 0; i < CPM_MAXBD; i++) {
534 cpm->rxbuf[i] = dma_alloc_coherent(&cpm->ofdev->dev,
535 CPM_MAX_READ + 1,
536 &cpm->rxdma[i], GFP_KERNEL);
537 if (!cpm->rxbuf[i]) {
538 ret = -ENOMEM;
539 goto out_muram;
540 }
541 out_be32(&rbdf[i].cbd_bufaddr, ((cpm->rxdma[i] + 1) & ~1));
542
543 cpm->txbuf[i] = (unsigned char *)dma_alloc_coherent(&cpm->ofdev->dev, CPM_MAX_READ + 1, &cpm->txdma[i], GFP_KERNEL);
544 if (!cpm->txbuf[i]) {
545 ret = -ENOMEM;
546 goto out_muram;
547 }
548 out_be32(&tbdf[i].cbd_bufaddr, cpm->txdma[i]);
549 }
550
551 /* Initialize Tx/Rx parameters. */
552
553 cpm_reset_i2c_params(cpm);
554
555 dev_dbg(&cpm->ofdev->dev, "i2c_ram 0x%p, i2c_addr 0x%04x, freq %d\n",
556 cpm->i2c_ram, cpm->i2c_addr, cpm->freq);
557 dev_dbg(&cpm->ofdev->dev, "tbase 0x%04x, rbase 0x%04x\n",
558 (u8 __iomem *)cpm->tbase - DPRAM_BASE,
559 (u8 __iomem *)cpm->rbase - DPRAM_BASE);
560
561 cpm_command(cpm->cp_command, CPM_CR_INIT_TRX);
562
563 /*
564 * Select an invalid address. Just make sure we don't use loopback mode
565 */
566 out_8(&cpm->i2c_reg->i2add, 0x7f << 1);
567
568 /*
569 * PDIV is set to 00 in i2mod, so brgclk/32 is used as input to the
570 * i2c baud rate generator. This is divided by 2 x (DIV + 3) to get
571 * the actual i2c bus frequency.
572 */
573 brg = get_brgfreq() / (32 * 2 * cpm->freq) - 3;
574 out_8(&cpm->i2c_reg->i2brg, brg);
575
576 out_8(&cpm->i2c_reg->i2mod, 0x00);
577 out_8(&cpm->i2c_reg->i2com, I2COM_MASTER); /* Master mode */
578
579 /* Disable interrupts. */
580 out_8(&cpm->i2c_reg->i2cmr, 0);
581 out_8(&cpm->i2c_reg->i2cer, 0xff);
582
583 return 0;
584
585 out_muram:
586 for (i = 0; i < CPM_MAXBD; i++) {
587 if (cpm->rxbuf[i])
588 dma_free_coherent(&cpm->ofdev->dev, CPM_MAX_READ + 1,
589 cpm->rxbuf[i], cpm->rxdma[i]);
590 if (cpm->txbuf[i])
591 dma_free_coherent(&cpm->ofdev->dev, CPM_MAX_READ + 1,
592 cpm->txbuf[i], cpm->txdma[i]);
593 }
594 cpm_muram_free(cpm->dp_addr);
595 out_reg:
596 iounmap(cpm->i2c_reg);
597 out_ram:
598 if ((cpm->version == 1) && (!cpm->i2c_addr))
599 iounmap(cpm->i2c_ram);
600 if (cpm->version == 2)
601 cpm_muram_free(cpm->i2c_addr);
602 out_irq:
603 free_irq(cpm->irq, &cpm->adap);
604 return ret;
605 }
606
607 static void cpm_i2c_shutdown(struct cpm_i2c *cpm)
608 {
609 int i;
610
611 /* Shut down I2C. */
612 clrbits8(&cpm->i2c_reg->i2mod, I2MOD_EN);
613
614 /* Disable interrupts */
615 out_8(&cpm->i2c_reg->i2cmr, 0);
616 out_8(&cpm->i2c_reg->i2cer, 0xff);
617
618 free_irq(cpm->irq, &cpm->adap);
619
620 /* Free all memory */
621 for (i = 0; i < CPM_MAXBD; i++) {
622 dma_free_coherent(&cpm->ofdev->dev, CPM_MAX_READ + 1,
623 cpm->rxbuf[i], cpm->rxdma[i]);
624 dma_free_coherent(&cpm->ofdev->dev, CPM_MAX_READ + 1,
625 cpm->txbuf[i], cpm->txdma[i]);
626 }
627
628 cpm_muram_free(cpm->dp_addr);
629 iounmap(cpm->i2c_reg);
630
631 if ((cpm->version == 1) && (!cpm->i2c_addr))
632 iounmap(cpm->i2c_ram);
633 if (cpm->version == 2)
634 cpm_muram_free(cpm->i2c_addr);
635 }
636
637 static int cpm_i2c_probe(struct platform_device *ofdev)
638 {
639 int result, len;
640 struct cpm_i2c *cpm;
641 const u32 *data;
642
643 cpm = kzalloc(sizeof(struct cpm_i2c), GFP_KERNEL);
644 if (!cpm)
645 return -ENOMEM;
646
647 cpm->ofdev = ofdev;
648
649 platform_set_drvdata(ofdev, cpm);
650
651 cpm->adap = cpm_ops;
652 i2c_set_adapdata(&cpm->adap, cpm);
653 cpm->adap.dev.parent = &ofdev->dev;
654 cpm->adap.dev.of_node = of_node_get(ofdev->dev.of_node);
655
656 result = cpm_i2c_setup(cpm);
657 if (result) {
658 dev_err(&ofdev->dev, "Unable to init hardware\n");
659 goto out_free;
660 }
661
662 /* register new adapter to i2c module... */
663
664 data = of_get_property(ofdev->dev.of_node, "linux,i2c-index", &len);
665 cpm->adap.nr = (data && len == 4) ? be32_to_cpup(data) : -1;
666 result = i2c_add_numbered_adapter(&cpm->adap);
667
668 if (result < 0) {
669 dev_err(&ofdev->dev, "Unable to register with I2C\n");
670 goto out_shut;
671 }
672
673 dev_dbg(&ofdev->dev, "hw routines for %s registered.\n",
674 cpm->adap.name);
675
676 return 0;
677 out_shut:
678 cpm_i2c_shutdown(cpm);
679 out_free:
680 kfree(cpm);
681
682 return result;
683 }
684
685 static int cpm_i2c_remove(struct platform_device *ofdev)
686 {
687 struct cpm_i2c *cpm = platform_get_drvdata(ofdev);
688
689 i2c_del_adapter(&cpm->adap);
690
691 cpm_i2c_shutdown(cpm);
692
693 kfree(cpm);
694
695 return 0;
696 }
697
698 static const struct of_device_id cpm_i2c_match[] = {
699 {
700 .compatible = "fsl,cpm1-i2c",
701 },
702 {
703 .compatible = "fsl,cpm2-i2c",
704 },
705 {},
706 };
707
708 MODULE_DEVICE_TABLE(of, cpm_i2c_match);
709
710 static struct platform_driver cpm_i2c_driver = {
711 .probe = cpm_i2c_probe,
712 .remove = cpm_i2c_remove,
713 .driver = {
714 .name = "fsl-i2c-cpm",
715 .of_match_table = cpm_i2c_match,
716 },
717 };
718
719 module_platform_driver(cpm_i2c_driver);
720
721 MODULE_AUTHOR("Jochen Friedrich <jochen@scram.de>");
722 MODULE_DESCRIPTION("I2C-Bus adapter routines for CPM boards");
723 MODULE_LICENSE("GPL");
Linux kernel - Deliverables
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