xref: /openbmc/u-boot/drivers/misc/ds4510.c (revision 6bb46790)
1 /*
2  * Copyright 2008 Extreme Engineering Solutions, Inc.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License
6  * Version 2 as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11  * GNU General Public License for more details.
12  *
13  * You should have received a copy of the GNU General Public License
14  * along with this program; if not, write to the Free Software
15  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
16  * MA 02111-1307 USA
17  */
18 
19 /*
20  * Driver for DS4510, a CPU supervisor with integrated EEPROM, SRAM,
21  * and 4 programmable non-volatile GPIO pins.
22  */
23 
24 #include <common.h>
25 #include <i2c.h>
26 #include <command.h>
27 #include <ds4510.h>
28 
29 /* Default to an address that hopefully won't corrupt other i2c devices */
30 #ifndef CONFIG_SYS_I2C_DS4510_ADDR
31 #define CONFIG_SYS_I2C_DS4510_ADDR	(~0)
32 #endif
33 
34 enum {
35 	DS4510_CMD_INFO,
36 	DS4510_CMD_DEVICE,
37 	DS4510_CMD_NV,
38 	DS4510_CMD_RSTDELAY,
39 	DS4510_CMD_OUTPUT,
40 	DS4510_CMD_INPUT,
41 	DS4510_CMD_PULLUP,
42 	DS4510_CMD_EEPROM,
43 	DS4510_CMD_SEEPROM,
44 	DS4510_CMD_SRAM,
45 };
46 
47 /*
48  * Write to DS4510, taking page boundaries into account
49  */
50 int ds4510_mem_write(uint8_t chip, int offset, uint8_t *buf, int count)
51 {
52 	int wrlen;
53 	int i = 0;
54 
55 	do {
56 		wrlen = DS4510_EEPROM_PAGE_SIZE -
57 			DS4510_EEPROM_PAGE_OFFSET(offset);
58 		if (count < wrlen)
59 			wrlen = count;
60 		if (i2c_write(chip, offset, 1, &buf[i], wrlen))
61 			return -1;
62 
63 		/*
64 		 * This delay isn't needed for SRAM writes but shouldn't delay
65 		 * things too much, so do it unconditionally for simplicity
66 		 */
67 		udelay(DS4510_EEPROM_PAGE_WRITE_DELAY_MS * 1000);
68 		count -= wrlen;
69 		offset += wrlen;
70 		i += wrlen;
71 	} while (count > 0);
72 
73 	return 0;
74 }
75 
76 /*
77  * General read from DS4510
78  */
79 int ds4510_mem_read(uint8_t chip, int offset, uint8_t *buf, int count)
80 {
81 	return i2c_read(chip, offset, 1, buf, count);
82 }
83 
84 /*
85  * Write SEE bit in config register.
86  * nv = 0 - Writes to SEEPROM registers behave like EEPROM
87  * nv = 1 - Writes to SEEPROM registers behave like SRAM
88  */
89 int ds4510_see_write(uint8_t chip, uint8_t nv)
90 {
91 	uint8_t data;
92 
93 	if (i2c_read(chip, DS4510_CFG, 1, &data, 1))
94 		return -1;
95 
96 	if (nv)	/* Treat SEEPROM bits as EEPROM */
97 		data &= ~DS4510_CFG_SEE;
98 	else	/* Treat SEEPROM bits as SRAM */
99 		data |= DS4510_CFG_SEE;
100 
101 	return ds4510_mem_write(chip, DS4510_CFG, &data, 1);
102 }
103 
104 /*
105  * Write de-assertion of reset signal delay
106  */
107 int ds4510_rstdelay_write(uint8_t chip, uint8_t delay)
108 {
109 	uint8_t data;
110 
111 	if (i2c_read(chip, DS4510_RSTDELAY, 1, &data, 1))
112 		return -1;
113 
114 	data &= ~DS4510_RSTDELAY_MASK;
115 	data |= delay & DS4510_RSTDELAY_MASK;
116 
117 	return ds4510_mem_write(chip, DS4510_RSTDELAY, &data, 1);
118 }
119 
120 /*
121  * Write pullup characteristics of IO pins
122  */
123 int ds4510_pullup_write(uint8_t chip, uint8_t val)
124 {
125 	val &= DS4510_IO_MASK;
126 
127 	return ds4510_mem_write(chip, DS4510_PULLUP, (uint8_t *)&val, 1);
128 }
129 
130 /*
131  * Read pullup characteristics of IO pins
132  */
133 int ds4510_pullup_read(uint8_t chip)
134 {
135 	uint8_t val;
136 
137 	if (i2c_read(chip, DS4510_PULLUP, 1, &val, 1))
138 		return -1;
139 
140 	return val & DS4510_IO_MASK;
141 }
142 
143 /*
144  * Write drive level of IO pins
145  */
146 int ds4510_gpio_write(uint8_t chip, uint8_t val)
147 {
148 	uint8_t data;
149 	int i;
150 
151 	for (i = 0; i < DS4510_NUM_IO; i++) {
152 		if (i2c_read(chip, DS4510_IO0 - i, 1, &data, 1))
153 			return -1;
154 
155 		if (val & (0x1 << i))
156 			data |= 0x1;
157 		else
158 			data &= ~0x1;
159 
160 		if (ds4510_mem_write(chip, DS4510_IO0 - i, &data, 1))
161 			return -1;
162 	}
163 
164 	return 0;
165 }
166 
167 /*
168  * Read drive level of IO pins
169  */
170 int ds4510_gpio_read(uint8_t chip)
171 {
172 	uint8_t data;
173 	int val = 0;
174 	int i;
175 
176 	for (i = 0; i < DS4510_NUM_IO; i++) {
177 		if (i2c_read(chip, DS4510_IO0 - i, 1, &data, 1))
178 			return -1;
179 
180 		if (data & 1)
181 			val |= (1 << i);
182 	}
183 
184 	return val;
185 }
186 
187 /*
188  * Read physical level of IO pins
189  */
190 int ds4510_gpio_read_val(uint8_t chip)
191 {
192 	uint8_t val;
193 
194 	if (i2c_read(chip, DS4510_IO_STATUS, 1, &val, 1))
195 		return -1;
196 
197 	return val & DS4510_IO_MASK;
198 }
199 
200 #ifdef CONFIG_CMD_DS4510
201 #ifdef CONFIG_CMD_DS4510_INFO
202 /*
203  * Display DS4510 information
204  */
205 static int ds4510_info(uint8_t chip)
206 {
207 	int i;
208 	int tmp;
209 	uint8_t data;
210 
211 	printf("DS4510 @ 0x%x:\n\n", chip);
212 
213 	if (i2c_read(chip, DS4510_RSTDELAY, 1, &data, 1))
214 		return -1;
215 	printf("rstdelay = 0x%x\n\n", data & DS4510_RSTDELAY_MASK);
216 
217 	if (i2c_read(chip, DS4510_CFG, 1, &data, 1))
218 		return -1;
219 	printf("config   = 0x%x\n", data);
220 	printf(" /ready  = %d\n", data & DS4510_CFG_READY ? 1 : 0);
221 	printf(" trip pt = %d\n", data & DS4510_CFG_TRIP_POINT ? 1 : 0);
222 	printf(" rst sts = %d\n", data & DS4510_CFG_RESET ? 1 : 0);
223 	printf(" /see    = %d\n", data & DS4510_CFG_SEE ? 1 : 0);
224 	printf(" swrst   = %d\n\n", data & DS4510_CFG_SWRST ? 1 : 0);
225 
226 	printf("gpio pins: 3210\n");
227 	printf("---------------\n");
228 	printf("pullup     ");
229 
230 	tmp = ds4510_pullup_read(chip);
231 	if (tmp == -1)
232 		return tmp;
233 	for (i = DS4510_NUM_IO - 1; i >= 0; i--)
234 		printf("%d", (tmp & (1 << i)) ? 1 : 0);
235 	printf("\n");
236 
237 	printf("driven     ");
238 	tmp = ds4510_gpio_read(chip);
239 	if (tmp == -1)
240 		return -1;
241 	for (i = DS4510_NUM_IO - 1; i >= 0; i--)
242 		printf("%d", (tmp & (1 << i)) ? 1 : 0);
243 	printf("\n");
244 
245 	printf("read       ");
246 	tmp = ds4510_gpio_read_val(chip);
247 	if (tmp == -1)
248 		return -1;
249 	for (i = DS4510_NUM_IO - 1; i >= 0; i--)
250 		printf("%d", (tmp & (1 << i)) ? 1 : 0);
251 	printf("\n");
252 
253 	return 0;
254 }
255 #endif /* CONFIG_CMD_DS4510_INFO */
256 
257 cmd_tbl_t cmd_ds4510[] = {
258 	U_BOOT_CMD_MKENT(device, 3, 0, (void *)DS4510_CMD_DEVICE, "", ""),
259 	U_BOOT_CMD_MKENT(nv, 3, 0, (void *)DS4510_CMD_NV, "", ""),
260 	U_BOOT_CMD_MKENT(output, 4, 0, (void *)DS4510_CMD_OUTPUT, "", ""),
261 	U_BOOT_CMD_MKENT(input, 3, 0, (void *)DS4510_CMD_INPUT, "", ""),
262 	U_BOOT_CMD_MKENT(pullup, 4, 0, (void *)DS4510_CMD_PULLUP, "", ""),
263 #ifdef CONFIG_CMD_DS4510_INFO
264 	U_BOOT_CMD_MKENT(info, 2, 0, (void *)DS4510_CMD_INFO, "", ""),
265 #endif
266 #ifdef CONFIG_CMD_DS4510_RST
267 	U_BOOT_CMD_MKENT(rstdelay, 3, 0, (void *)DS4510_CMD_RSTDELAY, "", ""),
268 #endif
269 #ifdef CONFIG_CMD_DS4510_MEM
270 	U_BOOT_CMD_MKENT(eeprom, 6, 0, (void *)DS4510_CMD_EEPROM, "", ""),
271 	U_BOOT_CMD_MKENT(seeprom, 6, 0, (void *)DS4510_CMD_SEEPROM, "", ""),
272 	U_BOOT_CMD_MKENT(sram, 6, 0, (void *)DS4510_CMD_SRAM, "", ""),
273 #endif
274 };
275 
276 int do_ds4510(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
277 {
278 	static uint8_t chip = CONFIG_SYS_I2C_DS4510_ADDR;
279 	cmd_tbl_t *c;
280 	ulong ul_arg2 = 0;
281 	ulong ul_arg3 = 0;
282 	int tmp;
283 #ifdef CONFIG_CMD_DS4510_MEM
284 	ulong addr;
285 	ulong off;
286 	ulong cnt;
287 	int end;
288 	int (*rw_func)(uint8_t, int, uint8_t *, int);
289 #endif
290 
291 	c = find_cmd_tbl(argv[1], cmd_ds4510, ARRAY_SIZE(cmd_ds4510));
292 
293 	/* All commands but "device" require 'maxargs' arguments */
294 	if (!c || !((argc == (c->maxargs)) ||
295 		(((int)c->cmd == DS4510_CMD_DEVICE) &&
296 		 (argc == (c->maxargs - 1))))) {
297 		cmd_usage(cmdtp);
298 		return 1;
299 	}
300 
301 	/* arg2 used as chip addr and pin number */
302 	if (argc > 2)
303 		ul_arg2 = simple_strtoul(argv[2], NULL, 16);
304 
305 	/* arg3 used as output/pullup value */
306 	if (argc > 3)
307 		ul_arg3 = simple_strtoul(argv[3], NULL, 16);
308 
309 	switch ((int)c->cmd) {
310 	case DS4510_CMD_DEVICE:
311 		if (argc == 3)
312 			chip = ul_arg2;
313 		printf("Current device address: 0x%x\n", chip);
314 		return 0;
315 	case DS4510_CMD_NV:
316 		return ds4510_see_write(chip, ul_arg2);
317 	case DS4510_CMD_OUTPUT:
318 		tmp = ds4510_gpio_read(chip);
319 		if (tmp == -1)
320 			return -1;
321 		if (ul_arg3)
322 			tmp |= (1 << ul_arg2);
323 		else
324 			tmp &= ~(1 << ul_arg2);
325 		return ds4510_gpio_write(chip, tmp);
326 	case DS4510_CMD_INPUT:
327 		tmp = ds4510_gpio_read_val(chip);
328 		if (tmp == -1)
329 			return -1;
330 		return (tmp & (1 << ul_arg2)) != 0;
331 	case DS4510_CMD_PULLUP:
332 		tmp = ds4510_pullup_read(chip);
333 		if (tmp == -1)
334 			return -1;
335 		if (ul_arg3)
336 			tmp |= (1 << ul_arg2);
337 		else
338 			tmp &= ~(1 << ul_arg2);
339 		return ds4510_pullup_write(chip, tmp);
340 #ifdef CONFIG_CMD_DS4510_INFO
341 	case DS4510_CMD_INFO:
342 		return ds4510_info(chip);
343 #endif
344 #ifdef CONFIG_CMD_DS4510_RST
345 	case DS4510_CMD_RSTDELAY:
346 		return ds4510_rstdelay_write(chip, ul_arg2);
347 #endif
348 #ifdef CONFIG_CMD_DS4510_MEM
349 	case DS4510_CMD_EEPROM:
350 		end = DS4510_EEPROM + DS4510_EEPROM_SIZE;
351 		off = DS4510_EEPROM;
352 		break;
353 	case DS4510_CMD_SEEPROM:
354 		end = DS4510_SEEPROM + DS4510_SEEPROM_SIZE;
355 		off = DS4510_SEEPROM;
356 		break;
357 	case DS4510_CMD_SRAM:
358 		end = DS4510_SRAM + DS4510_SRAM_SIZE;
359 		off = DS4510_SRAM;
360 		break;
361 #endif
362 	default:
363 		/* We should never get here... */
364 		return 1;
365 	}
366 
367 #ifdef CONFIG_CMD_DS4510_MEM
368 	/* Only eeprom, seeprom, and sram commands should make it here */
369 	if (strcmp(argv[2], "read") == 0) {
370 		rw_func = ds4510_mem_read;
371 	} else if (strcmp(argv[2], "write") == 0) {
372 		rw_func = ds4510_mem_write;
373 	} else {
374 		cmd_usage(cmdtp);
375 		return 1;
376 	}
377 
378 	addr = simple_strtoul(argv[3], NULL, 16);
379 	off += simple_strtoul(argv[4], NULL, 16);
380 	cnt = simple_strtoul(argv[5], NULL, 16);
381 
382 	if ((off + cnt) > end) {
383 		printf("ERROR: invalid len\n");
384 		return -1;
385 	}
386 
387 	return rw_func(chip, off, (uint8_t *)addr, cnt);
388 #endif
389 }
390 
391 U_BOOT_CMD(
392 	ds4510,	6,	1,	do_ds4510,
393 	"ds4510 eeprom/seeprom/sram/gpio access",
394 	"device [dev]\n"
395 	"	- show or set current device address\n"
396 #ifdef CONFIG_CMD_DS4510_INFO
397 	"ds4510 info\n"
398 	"	- display ds4510 info\n"
399 #endif
400 	"ds4510 output pin 0|1\n"
401 	"	- set pin low or high-Z\n"
402 	"ds4510 input pin\n"
403 	"	- read value of pin\n"
404 	"ds4510 pullup pin 0|1\n"
405 	"	- disable/enable pullup on specified pin\n"
406 	"ds4510 nv 0|1\n"
407 	"	- make gpio and seeprom writes volatile/non-volatile"
408 #ifdef CONFIG_CMD_DS4510_RST
409 	"\n"
410 	"ds4510 rstdelay 0-3\n"
411 	"	- set reset output delay"
412 #endif
413 #ifdef CONFIG_CMD_DS4510_MEM
414 	"\n"
415 	"ds4510 eeprom read addr off cnt\n"
416 	"ds4510 eeprom write addr off cnt\n"
417 	"	- read/write 'cnt' bytes at EEPROM offset 'off'\n"
418 	"ds4510 seeprom read addr off cnt\n"
419 	"ds4510 seeprom write addr off cnt\n"
420 	"	- read/write 'cnt' bytes at SRAM-shadowed EEPROM offset 'off'\n"
421 	"ds4510 sram read addr off cnt\n"
422 	"ds4510 sram write addr off cnt\n"
423 	"	- read/write 'cnt' bytes at SRAM offset 'off'"
424 #endif
425 );
426 #endif /* CONFIG_CMD_DS4510 */
427