xref: /rk3399_rockchip-uboot/drivers/i2c/i2c_core.c (revision 83d271b5ffc19e98098861dd21e940cf53545a43)
1 /*
2  * Copyright (C) 2009 Sergey Kubushyn <ksi@koi8.net>
3  *
4  * (C) Copyright 2012
5  * Heiko Schocher, DENX Software Engineering, hs@denx.de.
6  *
7  * Multibus/multiadapter I2C core functions (wrappers)
8  *
9  * SPDX-License-Identifier:	GPL-2.0+
10  */
11 #include <common.h>
12 #include <i2c.h>
13 
14 struct i2c_adapter *i2c_get_adapter(int index)
15 {
16 	struct i2c_adapter *i2c_adap_p = ll_entry_start(struct i2c_adapter,
17 						i2c);
18 	int max = ll_entry_count(struct i2c_adapter, i2c);
19 	int i;
20 
21 	if (index >= max) {
22 		printf("Error, wrong i2c adapter %d max %d possible\n",
23 		       index, max);
24 		return i2c_adap_p;
25 	}
26 	if (index == 0)
27 		return i2c_adap_p;
28 
29 	for (i = 0; i < index; i++)
30 		i2c_adap_p++;
31 
32 	return i2c_adap_p;
33 }
34 
35 #if !defined(CONFIG_SYS_I2C_DIRECT_BUS)
36 struct i2c_bus_hose i2c_bus[CONFIG_SYS_NUM_I2C_BUSES] =
37 			CONFIG_SYS_I2C_BUSES;
38 #endif
39 
40 DECLARE_GLOBAL_DATA_PTR;
41 
42 void i2c_reloc_fixup(void)
43 {
44 #if defined(CONFIG_NEEDS_MANUAL_RELOC)
45 	struct i2c_adapter *i2c_adap_p = ll_entry_start(struct i2c_adapter,
46 						i2c);
47 	struct i2c_adapter *tmp = i2c_adap_p;
48 	int max = ll_entry_count(struct i2c_adapter, i2c);
49 	int		i;
50 	unsigned long	addr;
51 
52 	if (gd->reloc_off == 0)
53 		return;
54 
55 	for (i = 0; i < max; i++) {
56 		/* i2c_init() */
57 		addr = (unsigned long)i2c_adap_p->init;
58 		addr += gd->reloc_off;
59 		i2c_adap_p->init = (void (*)(int, int))addr;
60 		/* i2c_probe() */
61 		addr = (unsigned long)i2c_adap_p->probe;
62 		addr += gd->reloc_off;
63 		i2c_adap_p->probe = (int (*)(uint8_t))addr;
64 		/* i2c_read() */
65 		addr = (unsigned long)i2c_adap_p->read;
66 		addr += gd->reloc_off;
67 		i2c_adap_p->read = (int (*)(uint8_t, uint, int, uint8_t *,
68 					int))addr;
69 		/* i2c_write() */
70 		addr = (unsigned long)i2c_adap_p->write;
71 		addr += gd->reloc_off;
72 		i2c_adap_p->write = (int (*)(uint8_t, uint, int, uint8_t *,
73 					int))addr;
74 		/* i2c_set_bus_speed() */
75 		addr = (unsigned long)i2c_adap_p->set_bus_speed;
76 		addr += gd->reloc_off;
77 		i2c_adap_p->set_bus_speed = (uint (*)(uint))addr;
78 		/* name */
79 		addr = (unsigned long)i2c_adap_p->name;
80 		addr += gd->reloc_off;
81 		i2c_adap_p->name = (char *)addr;
82 		tmp++;
83 		i2c_adap_p = tmp;
84 	}
85 #endif
86 }
87 
88 #ifndef CONFIG_SYS_I2C_DIRECT_BUS
89 /*
90  * i2c_mux_set()
91  * -------------
92  *
93  * This turns on the given channel on I2C multiplexer chip connected to
94  * a given I2C adapter directly or via other multiplexers. In the latter
95  * case the entire multiplexer chain must be initialized first starting
96  * with the one connected directly to the adapter. When disabling a chain
97  * muxes must be programmed in reverse order, starting with the one
98  * farthest from the adapter.
99  *
100  * mux_id is the multiplexer chip type from defined in i2c.h. So far only
101  * NXP (Philips) PCA954x multiplexers are supported. Switches are NOT
102  * supported (anybody uses them?)
103  */
104 
105 static int i2c_mux_set(struct i2c_adapter *adap, int mux_id, int chip,
106 			int channel)
107 {
108 	uint8_t	buf;
109 	int ret;
110 
111 	/* channel < 0 - turn off the mux */
112 	if (channel < 0) {
113 		buf = 0;
114 		ret = adap->write(adap, chip, 0, 0, &buf, 1);
115 		if (ret)
116 			printf("%s: Could not turn off the mux.\n", __func__);
117 		return ret;
118 	}
119 
120 	switch (mux_id) {
121 	case I2C_MUX_PCA9540_ID:
122 	case I2C_MUX_PCA9542_ID:
123 		if (channel > 1)
124 			return -1;
125 		buf = (uint8_t)((channel & 0x01) | (1 << 2));
126 		break;
127 	case I2C_MUX_PCA9544_ID:
128 		if (channel > 3)
129 			return -1;
130 		buf = (uint8_t)((channel & 0x03) | (1 << 2));
131 		break;
132 	case I2C_MUX_PCA9547_ID:
133 		if (channel > 7)
134 			return -1;
135 		buf = (uint8_t)((channel & 0x07) | (1 << 3));
136 		break;
137 	case I2C_MUX_PCA9548_ID:
138 		if (channel > 7)
139 			return -1;
140 		buf = (uint8_t)(0x01 << channel);
141 		break;
142 	default:
143 		printf("%s: wrong mux id: %d\n", __func__, mux_id);
144 		return -1;
145 	}
146 
147 	ret = adap->write(adap, chip, 0, 0, &buf, 1);
148 	if (ret)
149 		printf("%s: could not set mux: id: %d chip: %x channel: %d\n",
150 		       __func__, mux_id, chip, channel);
151 	return ret;
152 }
153 
154 static int i2c_mux_set_all(void)
155 {
156 	struct i2c_bus_hose *i2c_bus_tmp = &i2c_bus[I2C_BUS];
157 	int i;
158 
159 	/* Connect requested bus if behind muxes */
160 	if (i2c_bus_tmp->next_hop[0].chip != 0) {
161 		/* Set all muxes along the path to that bus */
162 		for (i = 0; i < CONFIG_SYS_I2C_MAX_HOPS; i++) {
163 			int	ret;
164 
165 			if (i2c_bus_tmp->next_hop[i].chip == 0)
166 				break;
167 
168 			ret = i2c_mux_set(I2C_ADAP,
169 					i2c_bus_tmp->next_hop[i].mux.id,
170 					i2c_bus_tmp->next_hop[i].chip,
171 					i2c_bus_tmp->next_hop[i].channel);
172 			if (ret != 0)
173 				return ret;
174 		}
175 	}
176 	return 0;
177 }
178 
179 static int i2c_mux_disconnet_all(void)
180 {
181 	struct	i2c_bus_hose *i2c_bus_tmp = &i2c_bus[I2C_BUS];
182 	int	i;
183 	uint8_t	buf;
184 
185 	if (I2C_ADAP->init_done == 0)
186 		return 0;
187 
188 	/* Disconnect current bus (turn off muxes if any) */
189 	if ((i2c_bus_tmp->next_hop[0].chip != 0) &&
190 	    (I2C_ADAP->init_done != 0)) {
191 		i = CONFIG_SYS_I2C_MAX_HOPS;
192 		do {
193 			uint8_t	chip;
194 			int ret;
195 
196 			chip = i2c_bus_tmp->next_hop[--i].chip;
197 			if (chip == 0)
198 				continue;
199 
200 			ret = I2C_ADAP->write(I2C_ADAP, chip, 0, 0, &buf, 1);
201 			if (ret != 0) {
202 				printf("i2c: mux diconnect error\n");
203 				return ret;
204 			}
205 		} while (i > 0);
206 	}
207 
208 	return 0;
209 }
210 #endif
211 
212 /*
213  * i2c_init_bus():
214  * ---------------
215  *
216  * Initializes one bus. Will initialize the parent adapter. No current bus
217  * changes, no mux (if any) setup.
218  */
219 static void i2c_init_bus(unsigned int bus_no, int speed, int slaveaddr)
220 {
221 	if (bus_no >= CONFIG_SYS_NUM_I2C_BUSES)
222 		return;
223 
224 	I2C_ADAP->init(I2C_ADAP, speed, slaveaddr);
225 
226 	if (gd->flags & GD_FLG_RELOC) {
227 		I2C_ADAP->init_done = 1;
228 		I2C_ADAP->speed = speed;
229 		I2C_ADAP->slaveaddr = slaveaddr;
230 	}
231 }
232 
233 /* implement possible board specific board init */
234 static void __def_i2c_init_board(void)
235 {
236 }
237 void i2c_init_board(void)
238 	__attribute__((weak, alias("__def_i2c_init_board")));
239 
240 /*
241  * i2c_init_all():
242  *
243  * not longer needed, will deleted. Actual init the SPD_BUS
244  * for compatibility.
245  * i2c_adap[] must be initialized beforehead with function pointers and
246  * data, including speed and slaveaddr.
247  */
248 void i2c_init_all(void)
249 {
250 	i2c_init_board();
251 	i2c_set_bus_num(CONFIG_SYS_SPD_BUS_NUM);
252 	return;
253 }
254 
255 /*
256  * i2c_get_bus_num():
257  * ------------------
258  *
259  *  Returns index of currently active I2C bus.  Zero-based.
260  */
261 unsigned int i2c_get_bus_num(void)
262 {
263 	return gd->cur_i2c_bus;
264 }
265 
266 /*
267  * i2c_set_bus_num():
268  * ------------------
269  *
270  *  Change the active I2C bus. Subsequent read/write calls will
271  *  go to this one. Sets all of the muxes in a proper condition
272  *  if that bus is behind muxes.
273  *  If previously selected bus is behind the muxes turns off all the
274  *  muxes along the path to that bus.
275  *
276  *	bus - bus index, zero based
277  *
278  *	Returns: 0 on success, not 0 on failure
279  */
280 int i2c_set_bus_num(unsigned int bus)
281 {
282 	int max;
283 
284 	if ((bus == I2C_BUS) && (I2C_ADAP->init_done > 0))
285 		return 0;
286 
287 #ifndef CONFIG_SYS_I2C_DIRECT_BUS
288 	if (bus >= CONFIG_SYS_NUM_I2C_BUSES)
289 		return -1;
290 #endif
291 
292 	max = ll_entry_count(struct i2c_adapter, i2c);
293 	if (I2C_ADAPTER(bus) >= max) {
294 		printf("Error, wrong i2c adapter %d max %d possible\n",
295 		       I2C_ADAPTER(bus), max);
296 		return -2;
297 	}
298 
299 #ifndef CONFIG_SYS_I2C_DIRECT_BUS
300 	i2c_mux_disconnet_all();
301 #endif
302 
303 	gd->cur_i2c_bus = bus;
304 	if (I2C_ADAP->init_done == 0)
305 		i2c_init_bus(bus, I2C_ADAP->speed, I2C_ADAP->slaveaddr);
306 
307 #ifndef CONFIG_SYS_I2C_DIRECT_BUS
308 	i2c_mux_set_all();
309 #endif
310 	return 0;
311 }
312 
313 /*
314  * Probe the given I2C chip address.  Returns 0 if a chip responded,
315  * not 0 on failure.
316  */
317 int i2c_probe(uint8_t chip)
318 {
319 	return I2C_ADAP->probe(I2C_ADAP, chip);
320 }
321 
322 /*
323  * Read/Write interface:
324  *   chip:    I2C chip address, range 0..127
325  *   addr:    Memory (register) address within the chip
326  *   alen:    Number of bytes to use for addr (typically 1, 2 for larger
327  *              memories, 0 for register type devices with only one
328  *              register)
329  *   buffer:  Where to read/write the data
330  *   len:     How many bytes to read/write
331  *
332  *   Returns: 0 on success, not 0 on failure
333  */
334 int i2c_read(uint8_t chip, unsigned int addr, int alen,
335 				uint8_t *buffer, int len)
336 {
337 	return I2C_ADAP->read(I2C_ADAP, chip, addr, alen, buffer, len);
338 }
339 
340 int i2c_write(uint8_t chip, unsigned int addr, int alen,
341 				uint8_t *buffer, int len)
342 {
343 	return I2C_ADAP->write(I2C_ADAP, chip, addr, alen, buffer, len);
344 }
345 
346 unsigned int i2c_set_bus_speed(unsigned int speed)
347 {
348 	unsigned int ret;
349 
350 	if (I2C_ADAP->set_bus_speed == NULL)
351 		return 0;
352 	ret = I2C_ADAP->set_bus_speed(I2C_ADAP, speed);
353 	if (gd->flags & GD_FLG_RELOC)
354 		I2C_ADAP->speed = ret;
355 
356 	return ret;
357 }
358 
359 unsigned int i2c_get_bus_speed(void)
360 {
361 	struct i2c_adapter *cur = I2C_ADAP;
362 	return cur->speed;
363 }
364 
365 uint8_t i2c_reg_read(uint8_t addr, uint8_t reg)
366 {
367 	uint8_t buf;
368 
369 #ifdef CONFIG_8xx
370 	/* MPC8xx needs this.  Maybe one day we can get rid of it. */
371 	/* maybe it is now the time for it ... */
372 	i2c_set_bus_num(i2c_get_bus_num());
373 #endif
374 	i2c_read(addr, reg, 1, &buf, 1);
375 
376 #ifdef DEBUG
377 	printf("%s: bus=%d addr=0x%02x, reg=0x%02x, val=0x%02x\n",
378 	       __func__, i2c_get_bus_num(), addr, reg, buf);
379 #endif
380 
381 	return buf;
382 }
383 
384 void i2c_reg_write(uint8_t addr, uint8_t reg, uint8_t val)
385 {
386 #ifdef CONFIG_8xx
387 	/* MPC8xx needs this.  Maybe one day we can get rid of it. */
388 	/* maybe it is now the time for it ... */
389 	i2c_set_bus_num(i2c_get_bus_num());
390 #endif
391 
392 #ifdef DEBUG
393 	printf("%s: bus=%d addr=0x%02x, reg=0x%02x, val=0x%02x\n",
394 	       __func__, i2c_get_bus_num(), addr, reg, val);
395 #endif
396 
397 	i2c_write(addr, reg, 1, &val, 1);
398 }
399 
400 void __i2c_init(int speed, int slaveaddr)
401 {
402 	i2c_init_bus(i2c_get_bus_num(), speed, slaveaddr);
403 }
404 void i2c_init(int speed, int slaveaddr)
405 	__attribute__((weak, alias("__i2c_init")));
406