]>
git.ipfire.org Git - people/ms/u-boot.git/blob - board/esd/cpci750/i2c.c
3 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5 * See file CREDITS for list of people who contributed to this
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.
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.
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,
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
30 #include "../../Marvell/include/mv_gen_reg.h"
31 #include "../../Marvell/include/core.h"
42 /* Assuming that there is only one master on the bus (us) */
44 static void i2c_init (int speed
, int slaveaddr
)
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 */
52 DP (puts ("i2c_init\n"));
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
);
59 margin
= i2cFreq
- freq
;
61 margin
= freq
- i2cFreq
;
62 if (margin
< minMargin
) {
70 DP (puts ("setup i2c bus\n"));
74 GT_REG_WRITE (I2C_SOFT_RESET
, 0);
76 GT_REG_WRITE (I2C_CONTROL
, 0);
79 DP (puts ("set baudrate\n"));
81 GT_REG_WRITE (I2C_STATUS_BAUDE_RATE
, (actualM
<< 3) | actualN
);
84 DP (puts ("udelay...\n"));
88 GT_REG_WRITE (I2C_CONTROL
, (0x1 << 2) | (0x1 << 6));
93 static uchar
i2c_select_device (uchar dev_addr
, uchar read
, int ten_bit
)
95 unsigned int status
, data
, bits
= 7;
99 DP (puts ("i2c_select_device\n"));
101 /* Output slave address */
107 GT_REG_READ (I2C_CONTROL
, &control
);
108 control
|= (0x1 << 2);
109 GT_REG_WRITE (I2C_CONTROL
, control
);
112 GT_REG_READ (I2C_CONTROL
, &control
);
113 control
|= (0x1 << 5); /* generate the I2C_START_BIT */
114 GT_REG_WRITE (I2C_CONTROL
, control
);
116 RESET_REG_BITS (I2C_CONTROL
, (0x01 << 3));
119 GT_REG_READ (I2C_CONTROL
, &status
);
120 while ((status
& 0x08) != 0x08) {
121 GT_REG_READ (I2C_CONTROL
, &status
);
127 GT_REG_READ (I2C_STATUS_BAUDE_RATE
, &status
);
128 while (((status
& 0xff) != 0x08) && ((status
& 0xff) != 0x10)){
131 printf ("Failed to set startbit: 0x%02x\n", status
);
133 GT_REG_WRITE (I2C_CONTROL
, (0x1 << 4)); /*stop */
137 GT_REG_READ (I2C_STATUS_BAUDE_RATE
, &status
);
141 DP (puts ("i2c_select_device:write addr byte\n"));
143 /* assert the address */
145 data
= (dev_addr
<< 1);
146 /* set the read bit */
148 GT_REG_WRITE (I2C_DATA
, data
);
150 RESET_REG_BITS (I2C_CONTROL
, BIT3
);
153 GT_REG_READ (I2C_CONTROL
, &status
);
154 while ((status
& 0x08) != 0x08) {
155 GT_REG_READ (I2C_CONTROL
, &status
);
158 GT_REG_READ (I2C_STATUS_BAUDE_RATE
, &status
);
160 while (((status
& 0xff) != 0x40) && ((status
& 0xff) != 0x18)) {
163 printf ("Failed to write address: 0x%02x\n", status
);
165 GT_REG_WRITE (I2C_CONTROL
, (0x1 << 4)); /*stop */
168 GT_REG_READ (I2C_STATUS_BAUDE_RATE
, &status
);
174 printf ("10 bit I2C addressing not yet implemented\n");
181 static uchar
i2c_get_data (uchar
* return_data
, int len
)
184 unsigned int data
, status
;
187 DP (puts ("i2c_get_data\n"));
191 RESET_REG_BITS (I2C_CONTROL
, BIT3
);
194 /* Get and return the data */
196 GT_REG_READ (I2C_CONTROL
, &status
);
197 while ((status
& 0x08) != 0x08) {
198 GT_REG_READ (I2C_CONTROL
, &status
);
201 GT_REG_READ (I2C_STATUS_BAUDE_RATE
, &status
);
203 while ((status
& 0xff) != 0x50) {
206 printf ("Failed to get data len status: 0x%02x\n", status
);
208 GT_REG_WRITE (I2C_CONTROL
, (0x1 << 4)); /*stop */
212 GT_REG_READ (I2C_STATUS_BAUDE_RATE
, &status
);
215 GT_REG_READ (I2C_DATA
, &data
);
217 *return_data
= (uchar
) data
;
221 RESET_REG_BITS (I2C_CONTROL
, BIT2
| BIT3
);
225 GT_REG_READ (I2C_CONTROL
, &status
);
226 while ((status
& 0x08) != 0x08) {
227 GT_REG_READ (I2C_CONTROL
, &status
);
230 while ((status
& 0xff) != 0x58) {
232 GT_REG_WRITE (I2C_CONTROL
, (0x1 << 4)); /*stop */
235 GT_REG_READ (I2C_STATUS_BAUDE_RATE
, &status
);
238 GT_REG_WRITE (I2C_CONTROL
, (0x1 << 4)); /* stop */
240 RESET_REG_BITS (I2C_CONTROL
, (0x1 << 3));
247 static uchar
i2c_write_data (unsigned int *data
, int len
)
252 unsigned int *temp_ptr
= data
;
254 DP (puts ("i2c_write_data\n"));
258 temp
= (unsigned int) (*temp_ptr
);
259 GT_REG_WRITE (I2C_DATA
, temp
);
261 RESET_REG_BITS (I2C_CONTROL
, (0x1 << 3));
264 GT_REG_READ (I2C_CONTROL
, &status
);
265 while ((status
& 0x08) != 0x08) {
266 GT_REG_READ (I2C_CONTROL
, &status
);
269 GT_REG_READ (I2C_STATUS_BAUDE_RATE
, &status
);
271 while ((status
& 0xff) != 0x28) {
273 GT_REG_WRITE (I2C_CONTROL
, (0x1 << 4)); /*stop */
277 GT_REG_READ (I2C_STATUS_BAUDE_RATE
, &status
);
287 static uchar
i2c_write_byte (unsigned char *data
, int len
)
292 unsigned char *temp_ptr
= data
;
294 DP (puts ("i2c_write_byte\n"));
298 /* Set and assert the data */
300 GT_REG_WRITE (I2C_DATA
, temp
);
302 RESET_REG_BITS (I2C_CONTROL
, (0x1 << 3));
306 GT_REG_READ (I2C_CONTROL
, &status
);
307 while ((status
& 0x08) != 0x08) {
308 GT_REG_READ (I2C_CONTROL
, &status
);
311 GT_REG_READ (I2C_STATUS_BAUDE_RATE
, &status
);
313 while ((status
& 0xff) != 0x28) {
315 GT_REG_WRITE (I2C_CONTROL
, (0x1 << 4)); /*stop */
319 GT_REG_READ (I2C_STATUS_BAUDE_RATE
, &status
);
329 i2c_set_dev_offset (uchar dev_addr
, unsigned int offset
, int ten_bit
,
333 unsigned int table
[2];
335 table
[1] = (offset
) & 0x0ff; /* low byte */
336 table
[0] = (offset
>> 8) & 0x0ff; /* high byte */
338 DP (puts ("i2c_set_dev_offset\n"));
340 status
= i2c_select_device (dev_addr
, 0, ten_bit
);
343 22 printf ("Failed to select device setting offset: 0x%02x\n",
348 /* check the address offset length */
350 /* no address offset */
352 else if (alen
== 1) {
353 /* 1 byte address offset */
354 status
= i2c_write_data (&offset
, 1);
357 printf ("Failed to write data: 0x%02x\n", status
);
361 } else if (alen
== 2) {
362 /* 2 bytes address offset */
363 status
= i2c_write_data (table
, 2);
366 printf ("Failed to write data: 0x%02x\n", status
);
371 /* address offset unknown or not supported */
372 printf ("Address length offset %d is not supported\n", alen
);
375 return 0; /* sucessful completion */
379 i2c_read (uchar dev_addr
, unsigned int offset
, int alen
, uchar
* data
,
383 unsigned int i2cFreq
= CONFIG_SYS_I2C_SPEED
;
385 DP (puts ("i2c_read\n"));
387 i2c_init (i2cFreq
, 0); /* set the i2c frequency */
389 status
= i2c_set_dev_offset (dev_addr
, offset
, 0, alen
); /* send the slave address + offset */
392 printf ("Failed to set slave address & offset: 0x%02x\n",
398 status
= i2c_select_device (dev_addr
, 1, 0);
401 printf ("Failed to select device for data read: 0x%02x\n",
407 status
= i2c_get_data (data
, len
);
410 printf ("Data not read: 0x%02x\n", status
);
421 GT_REG_WRITE (I2C_CONTROL
, (0x1 << 4));
427 i2c_write (uchar dev_addr
, unsigned int offset
, int alen
, uchar
* data
,
431 unsigned int i2cFreq
= CONFIG_SYS_I2C_SPEED
;
433 DP (puts ("i2c_write\n"));
435 i2c_init (i2cFreq
, 0); /* set the i2c frequency */
437 status
= i2c_set_dev_offset (dev_addr
, offset
, 0, alen
); /* send the slave address + offset */
440 printf ("Failed to set slave address & offset: 0x%02x\n",
447 status
= i2c_write_byte (data
, len
); /* write the data */
450 printf ("Data not written: 0x%02x\n", status
);
454 /* issue a stop bit */
460 int i2c_probe (uchar chip
)
464 unsigned int i2c_status
;
467 unsigned int i2cFreq
= CONFIG_SYS_I2C_SPEED
;
469 DP (puts ("i2c_probe\n"));
471 i2c_init (i2cFreq
, 0); /* set the i2c frequency */
473 status
= i2c_set_dev_offset (chip
, 0, 0, 0); /* send the slave address + no offset */
476 printf ("Failed to set slave address: 0x%02x\n", status
);
481 GT_REG_READ (I2C_STATUS_BAUDE_RATE
, &i2c_status
);
482 printf ("address %#x returned %#x\n", chip
, i2c_status
);
484 /* issue a stop bit */
486 return 0; /* successful completion */