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rename CFG_ macros to CONFIG_SYS
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1 /*
2 * (C) Copyright 2000
3 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4 *
5 * See file CREDITS for list of people who contributed to this
6 * project.
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License as
10 * published by the Free Software Foundation; either version 2 of
11 * the License, or (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
21 * MA 02111-1307 USA
22 *
23 * Hacked for the DB64360 board by Ingo.Assmus@keymile.com
24 * extra improvments by Brain Waite
25 * for cpci750 by reinhard.arlt@esd-electronics.com
26 */
27 #include <common.h>
28 #include <mpc8xx.h>
29 #include <malloc.h>
30 #include "../../Marvell/include/mv_gen_reg.h"
31 #include "../../Marvell/include/core.h"
32
33 #define I2C_DELAY 100
34 #undef DEBUG_I2C
35
36 #ifdef DEBUG_I2C
37 #define DP(x) x
38 #else
39 #define DP(x)
40 #endif
41
42 /* Assuming that there is only one master on the bus (us) */
43
44 static void i2c_init (int speed, int slaveaddr)
45 {
46 unsigned int n, m, freq, margin, power;
47 unsigned int actualN = 0, actualM = 0;
48 unsigned int minMargin = 0xffffffff;
49 unsigned int tclk = CONFIG_SYS_TCLK;
50 unsigned int i2cFreq = speed; /* 100000 max. Fast mode not supported */
51
52 DP (puts ("i2c_init\n"));
53 /* gtI2cMasterInit */
54 for (n = 0; n < 8; n++) {
55 for (m = 0; m < 16; m++) {
56 power = 2 << n; /* power = 2^(n+1) */
57 freq = tclk / (10 * (m + 1) * power);
58 if (i2cFreq > freq)
59 margin = i2cFreq - freq;
60 else
61 margin = freq - i2cFreq;
62 if (margin < minMargin) {
63 minMargin = margin;
64 actualN = n;
65 actualM = m;
66 }
67 }
68 }
69
70 DP (puts ("setup i2c bus\n"));
71
72 /* Setup bus */
73 /* gtI2cReset */
74 GT_REG_WRITE (I2C_SOFT_RESET, 0);
75 asm(" sync");
76 GT_REG_WRITE (I2C_CONTROL, 0);
77 asm(" sync");
78
79 DP (puts ("set baudrate\n"));
80
81 GT_REG_WRITE (I2C_STATUS_BAUDE_RATE, (actualM << 3) | actualN);
82 asm(" sync");
83
84 DP (puts ("udelay...\n"));
85
86 udelay (I2C_DELAY);
87
88 GT_REG_WRITE (I2C_CONTROL, (0x1 << 2) | (0x1 << 6));
89 asm(" sync");
90 }
91
92
93 static uchar i2c_select_device (uchar dev_addr, uchar read, int ten_bit)
94 {
95 unsigned int status, data, bits = 7;
96 unsigned int control;
97 int count = 0;
98
99 DP (puts ("i2c_select_device\n"));
100
101 /* Output slave address */
102
103 if (ten_bit) {
104 bits = 10;
105 }
106
107 GT_REG_READ (I2C_CONTROL, &control);
108 control |= (0x1 << 2);
109 GT_REG_WRITE (I2C_CONTROL, control);
110 asm(" sync");
111
112 GT_REG_READ (I2C_CONTROL, &control);
113 control |= (0x1 << 5); /* generate the I2C_START_BIT */
114 GT_REG_WRITE (I2C_CONTROL, control);
115 asm(" sync");
116 RESET_REG_BITS (I2C_CONTROL, (0x01 << 3));
117 asm(" sync");
118
119 GT_REG_READ (I2C_CONTROL, &status);
120 while ((status & 0x08) != 0x08) {
121 GT_REG_READ (I2C_CONTROL, &status);
122 }
123
124
125 count = 0;
126
127 GT_REG_READ (I2C_STATUS_BAUDE_RATE, &status);
128 while (((status & 0xff) != 0x08) && ((status & 0xff) != 0x10)){
129 if (count > 200) {
130 #ifdef DEBUG_I2C
131 printf ("Failed to set startbit: 0x%02x\n", status);
132 #endif
133 GT_REG_WRITE (I2C_CONTROL, (0x1 << 4)); /*stop */
134 asm(" sync");
135 return (status);
136 }
137 GT_REG_READ (I2C_STATUS_BAUDE_RATE, &status);
138 count++;
139 }
140
141 DP (puts ("i2c_select_device:write addr byte\n"));
142
143 /* assert the address */
144
145 data = (dev_addr << 1);
146 /* set the read bit */
147 data |= read;
148 GT_REG_WRITE (I2C_DATA, data);
149 asm(" sync");
150 RESET_REG_BITS (I2C_CONTROL, BIT3);
151 asm(" sync");
152
153 GT_REG_READ (I2C_CONTROL, &status);
154 while ((status & 0x08) != 0x08) {
155 GT_REG_READ (I2C_CONTROL, &status);
156 }
157
158 GT_REG_READ (I2C_STATUS_BAUDE_RATE, &status);
159 count = 0;
160 while (((status & 0xff) != 0x40) && ((status & 0xff) != 0x18)) {
161 if (count > 200) {
162 #ifdef DEBUG_I2C
163 printf ("Failed to write address: 0x%02x\n", status);
164 #endif
165 GT_REG_WRITE (I2C_CONTROL, (0x1 << 4)); /*stop */
166 return (status);
167 }
168 GT_REG_READ (I2C_STATUS_BAUDE_RATE, &status);
169 asm(" sync");
170 count++;
171 }
172
173 if (bits == 10) {
174 printf ("10 bit I2C addressing not yet implemented\n");
175 return (0xff);
176 }
177
178 return (0);
179 }
180
181 static uchar i2c_get_data (uchar * return_data, int len)
182 {
183
184 unsigned int data, status;
185 int count = 0;
186
187 DP (puts ("i2c_get_data\n"));
188
189 while (len) {
190
191 RESET_REG_BITS (I2C_CONTROL, BIT3);
192 asm(" sync");
193
194 /* Get and return the data */
195
196 GT_REG_READ (I2C_CONTROL, &status);
197 while ((status & 0x08) != 0x08) {
198 GT_REG_READ (I2C_CONTROL, &status);
199 }
200
201 GT_REG_READ (I2C_STATUS_BAUDE_RATE, &status);
202 count++;
203 while ((status & 0xff) != 0x50) {
204 if (count > 20) {
205 #ifdef DEBUG_I2C
206 printf ("Failed to get data len status: 0x%02x\n", status);
207 #endif
208 GT_REG_WRITE (I2C_CONTROL, (0x1 << 4)); /*stop */
209 asm(" sync");
210 return 0;
211 }
212 GT_REG_READ (I2C_STATUS_BAUDE_RATE, &status);
213 count++;
214 }
215 GT_REG_READ (I2C_DATA, &data);
216 len--;
217 *return_data = (uchar) data;
218 return_data++;
219
220 }
221 RESET_REG_BITS (I2C_CONTROL, BIT2 | BIT3);
222 asm(" sync");
223 count = 0;
224
225 GT_REG_READ (I2C_CONTROL, &status);
226 while ((status & 0x08) != 0x08) {
227 GT_REG_READ (I2C_CONTROL, &status);
228 }
229
230 while ((status & 0xff) != 0x58) {
231 if (count > 2000) {
232 GT_REG_WRITE (I2C_CONTROL, (0x1 << 4)); /*stop */
233 return (status);
234 }
235 GT_REG_READ (I2C_STATUS_BAUDE_RATE, &status);
236 count++;
237 }
238 GT_REG_WRITE (I2C_CONTROL, (0x1 << 4)); /* stop */
239 asm(" sync");
240 RESET_REG_BITS (I2C_CONTROL, (0x1 << 3));
241 asm(" sync");
242
243 return (0);
244 }
245
246
247 static uchar i2c_write_data (unsigned int *data, int len)
248 {
249 unsigned int status;
250 int count;
251 unsigned int temp;
252 unsigned int *temp_ptr = data;
253
254 DP (puts ("i2c_write_data\n"));
255
256 while (len) {
257 count = 0;
258 temp = (unsigned int) (*temp_ptr);
259 GT_REG_WRITE (I2C_DATA, temp);
260 asm(" sync");
261 RESET_REG_BITS (I2C_CONTROL, (0x1 << 3));
262 asm(" sync");
263
264 GT_REG_READ (I2C_CONTROL, &status);
265 while ((status & 0x08) != 0x08) {
266 GT_REG_READ (I2C_CONTROL, &status);
267 }
268
269 GT_REG_READ (I2C_STATUS_BAUDE_RATE, &status);
270 count++;
271 while ((status & 0xff) != 0x28) {
272 if (count > 200) {
273 GT_REG_WRITE (I2C_CONTROL, (0x1 << 4)); /*stop */
274 asm(" sync");
275 return (status);
276 }
277 GT_REG_READ (I2C_STATUS_BAUDE_RATE, &status);
278 count++;
279 }
280 len--;
281 temp_ptr++;
282 }
283 return (0);
284 }
285
286
287 static uchar i2c_write_byte (unsigned char *data, int len)
288 {
289 unsigned int status;
290 int count;
291 unsigned int temp;
292 unsigned char *temp_ptr = data;
293
294 DP (puts ("i2c_write_byte\n"));
295
296 while (len) {
297 count = 0;
298 /* Set and assert the data */
299 temp = *temp_ptr;
300 GT_REG_WRITE (I2C_DATA, temp);
301 asm(" sync");
302 RESET_REG_BITS (I2C_CONTROL, (0x1 << 3));
303 asm(" sync");
304
305
306 GT_REG_READ (I2C_CONTROL, &status);
307 while ((status & 0x08) != 0x08) {
308 GT_REG_READ (I2C_CONTROL, &status);
309 }
310
311 GT_REG_READ (I2C_STATUS_BAUDE_RATE, &status);
312 count++;
313 while ((status & 0xff) != 0x28) {
314 if (count > 200) {
315 GT_REG_WRITE (I2C_CONTROL, (0x1 << 4)); /*stop */
316 asm(" sync");
317 return (status);
318 }
319 GT_REG_READ (I2C_STATUS_BAUDE_RATE, &status);
320 count++;
321 }
322 len--;
323 temp_ptr++;
324 }
325 return (0);
326 }
327
328 static uchar
329 i2c_set_dev_offset (uchar dev_addr, unsigned int offset, int ten_bit,
330 int alen)
331 {
332 uchar status;
333 unsigned int table[2];
334
335 table[1] = (offset ) & 0x0ff; /* low byte */
336 table[0] = (offset >> 8) & 0x0ff; /* high byte */
337
338 DP (puts ("i2c_set_dev_offset\n"));
339
340 status = i2c_select_device (dev_addr, 0, ten_bit);
341 if (status) {
342 #ifdef DEBUG_I2C
343 22 printf ("Failed to select device setting offset: 0x%02x\n",
344 status);
345 #endif
346 return status;
347 }
348 /* check the address offset length */
349 if (alen == 0)
350 /* no address offset */
351 return (0);
352 else if (alen == 1) {
353 /* 1 byte address offset */
354 status = i2c_write_data (&offset, 1);
355 if (status) {
356 #ifdef DEBUG_I2C
357 printf ("Failed to write data: 0x%02x\n", status);
358 #endif
359 return status;
360 }
361 } else if (alen == 2) {
362 /* 2 bytes address offset */
363 status = i2c_write_data (table, 2);
364 if (status) {
365 #ifdef DEBUG_I2C
366 printf ("Failed to write data: 0x%02x\n", status);
367 #endif
368 return status;
369 }
370 } else {
371 /* address offset unknown or not supported */
372 printf ("Address length offset %d is not supported\n", alen);
373 return 1;
374 }
375 return 0; /* sucessful completion */
376 }
377
378 uchar
379 i2c_read (uchar dev_addr, unsigned int offset, int alen, uchar * data,
380 int len)
381 {
382 uchar status = 0;
383 unsigned int i2cFreq = CONFIG_SYS_I2C_SPEED;
384
385 DP (puts ("i2c_read\n"));
386
387 i2c_init (i2cFreq, 0); /* set the i2c frequency */
388
389 status = i2c_set_dev_offset (dev_addr, offset, 0, alen); /* send the slave address + offset */
390 if (status) {
391 #ifdef DEBUG_I2C
392 printf ("Failed to set slave address & offset: 0x%02x\n",
393 status);
394 #endif
395 return status;
396 }
397
398 status = i2c_select_device (dev_addr, 1, 0);
399 if (status) {
400 #ifdef DEBUG_I2C
401 printf ("Failed to select device for data read: 0x%02x\n",
402 status);
403 #endif
404 return status;
405 }
406
407 status = i2c_get_data (data, len);
408 if (status) {
409 #ifdef DEBUG_I2C
410 printf ("Data not read: 0x%02x\n", status);
411 #endif
412 return status;
413 }
414
415 return 0;
416 }
417
418
419 void i2c_stop (void)
420 {
421 GT_REG_WRITE (I2C_CONTROL, (0x1 << 4));
422 asm(" sync");
423 }
424
425
426 uchar
427 i2c_write (uchar dev_addr, unsigned int offset, int alen, uchar * data,
428 int len)
429 {
430 uchar status = 0;
431 unsigned int i2cFreq = CONFIG_SYS_I2C_SPEED;
432
433 DP (puts ("i2c_write\n"));
434
435 i2c_init (i2cFreq, 0); /* set the i2c frequency */
436
437 status = i2c_set_dev_offset (dev_addr, offset, 0, alen); /* send the slave address + offset */
438 if (status) {
439 #ifdef DEBUG_I2C
440 printf ("Failed to set slave address & offset: 0x%02x\n",
441 status);
442 #endif
443 return status;
444 }
445
446
447 status = i2c_write_byte (data, len); /* write the data */
448 if (status) {
449 #ifdef DEBUG_I2C
450 printf ("Data not written: 0x%02x\n", status);
451 #endif
452 return status;
453 }
454 /* issue a stop bit */
455 i2c_stop ();
456 return 0;
457 }
458
459
460 int i2c_probe (uchar chip)
461 {
462
463 #ifdef DEBUG_I2C
464 unsigned int i2c_status;
465 #endif
466 uchar status = 0;
467 unsigned int i2cFreq = CONFIG_SYS_I2C_SPEED;
468
469 DP (puts ("i2c_probe\n"));
470
471 i2c_init (i2cFreq, 0); /* set the i2c frequency */
472
473 status = i2c_set_dev_offset (chip, 0, 0, 0); /* send the slave address + no offset */
474 if (status) {
475 #ifdef DEBUG_I2C
476 printf ("Failed to set slave address: 0x%02x\n", status);
477 #endif
478 return (int) status;
479 }
480 #ifdef DEBUG_I2C
481 GT_REG_READ (I2C_STATUS_BAUDE_RATE, &i2c_status);
482 printf ("address %#x returned %#x\n", chip, i2c_status);
483 #endif
484 /* issue a stop bit */
485 i2c_stop ();
486 return 0; /* successful completion */
487 }