xref: /openbmc/u-boot/include/i2c.h (revision f3e9361771af69b12699c8e58b174d72f0bb545e)
1 /*
2  * Copyright (C) 2009 Sergey Kubushyn <ksi@koi8.net>
3  * Copyright (C) 2009 - 2013 Heiko Schocher <hs@denx.de>
4  * Changes for multibus/multiadapter I2C support.
5  *
6  * (C) Copyright 2001
7  * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com.
8  *
9  * See file CREDITS for list of people who contributed to this
10  * project.
11  *
12  * This program is free software; you can redistribute it and/or
13  * modify it under the terms of the GNU General Public License as
14  * published by the Free Software Foundation; either version 2 of
15  * the License, or (at your option) any later version.
16  *
17  * This program is distributed in the hope that it will be useful,
18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  * GNU General Public License for more details.
21  *
22  * You should have received a copy of the GNU General Public License
23  * along with this program; if not, write to the Free Software
24  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
25  * MA 02111-1307 USA
26  *
27  * The original I2C interface was
28  *   (C) 2000 by Paolo Scaffardi (arsenio@tin.it)
29  *   AIRVENT SAM s.p.a - RIMINI(ITALY)
30  * but has been changed substantially.
31  */
32 
33 #ifndef _I2C_H_
34 #define _I2C_H_
35 
36 /*
37  * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
38  *
39  * The implementation MUST NOT use static or global variables if the
40  * I2C routines are used to read SDRAM configuration information
41  * because this is done before the memories are initialized. Limited
42  * use of stack-based variables are OK (the initial stack size is
43  * limited).
44  *
45  * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
46  */
47 
48 /*
49  * Configuration items.
50  */
51 #define I2C_RXTX_LEN	128	/* maximum tx/rx buffer length */
52 
53 #if !defined(CONFIG_SYS_I2C_MAX_HOPS)
54 /* no muxes used bus = i2c adapters */
55 #define CONFIG_SYS_I2C_DIRECT_BUS	1
56 #define CONFIG_SYS_I2C_MAX_HOPS		0
57 #define CONFIG_SYS_NUM_I2C_BUSES	ll_entry_count(struct i2c_adapter, i2c)
58 #else
59 /* we use i2c muxes */
60 #undef CONFIG_SYS_I2C_DIRECT_BUS
61 #endif
62 
63 /* define the I2C bus number for RTC and DTT if not already done */
64 #if !defined(CONFIG_SYS_RTC_BUS_NUM)
65 #define CONFIG_SYS_RTC_BUS_NUM		0
66 #endif
67 #if !defined(CONFIG_SYS_DTT_BUS_NUM)
68 #define CONFIG_SYS_DTT_BUS_NUM		0
69 #endif
70 #if !defined(CONFIG_SYS_SPD_BUS_NUM)
71 #define CONFIG_SYS_SPD_BUS_NUM		0
72 #endif
73 
74 struct i2c_adapter {
75 	void		(*init)(struct i2c_adapter *adap, int speed,
76 				int slaveaddr);
77 	int		(*probe)(struct i2c_adapter *adap, uint8_t chip);
78 	int		(*read)(struct i2c_adapter *adap, uint8_t chip,
79 				uint addr, int alen, uint8_t *buffer,
80 				int len);
81 	int		(*write)(struct i2c_adapter *adap, uint8_t chip,
82 				uint addr, int alen, uint8_t *buffer,
83 				int len);
84 	uint		(*set_bus_speed)(struct i2c_adapter *adap,
85 				uint speed);
86 	int		speed;
87 	int		slaveaddr;
88 	int		init_done;
89 	int		hwadapnr;
90 	char		*name;
91 };
92 
93 #define U_BOOT_I2C_MKENT_COMPLETE(_init, _probe, _read, _write, \
94 		_set_speed, _speed, _slaveaddr, _hwadapnr, _name) \
95 	{ \
96 		.init		=	_init, \
97 		.probe		=	_probe, \
98 		.read		=	_read, \
99 		.write		=	_write, \
100 		.set_bus_speed	=	_set_speed, \
101 		.speed		=	_speed, \
102 		.slaveaddr	=	_slaveaddr, \
103 		.init_done	=	0, \
104 		.hwadapnr	=	_hwadapnr, \
105 		.name		=	#_name \
106 };
107 
108 #define U_BOOT_I2C_ADAP_COMPLETE(_name, _init, _probe, _read, _write, \
109 			_set_speed, _speed, _slaveaddr, _hwadapnr) \
110 	ll_entry_declare(struct i2c_adapter, _name, i2c) = \
111 	U_BOOT_I2C_MKENT_COMPLETE(_init, _probe, _read, _write, \
112 		 _set_speed, _speed, _slaveaddr, _hwadapnr, _name);
113 
114 struct i2c_adapter *i2c_get_adapter(int index);
115 
116 #ifndef CONFIG_SYS_I2C_DIRECT_BUS
117 struct i2c_mux {
118 	int	id;
119 	char	name[16];
120 };
121 
122 struct i2c_next_hop {
123 	struct i2c_mux		mux;
124 	uint8_t		chip;
125 	uint8_t		channel;
126 };
127 
128 struct i2c_bus_hose {
129 	int	adapter;
130 	struct i2c_next_hop	next_hop[CONFIG_SYS_I2C_MAX_HOPS];
131 };
132 #define I2C_NULL_HOP	{{-1, ""}, 0, 0}
133 extern struct i2c_bus_hose	i2c_bus[];
134 
135 #define I2C_ADAPTER(bus)	i2c_bus[bus].adapter
136 #else
137 #define I2C_ADAPTER(bus)	bus
138 #endif
139 #define	I2C_BUS			gd->cur_i2c_bus
140 
141 #define	I2C_ADAP_NR(bus)	i2c_get_adapter(I2C_ADAPTER(bus))
142 #define	I2C_ADAP		I2C_ADAP_NR(gd->cur_i2c_bus)
143 #define I2C_ADAP_HWNR		(I2C_ADAP->hwadapnr)
144 
145 #ifndef CONFIG_SYS_I2C_DIRECT_BUS
146 #define I2C_MUX_PCA9540_ID	1
147 #define I2C_MUX_PCA9540		{I2C_MUX_PCA9540_ID, "PCA9540B"}
148 #define I2C_MUX_PCA9542_ID	2
149 #define I2C_MUX_PCA9542		{I2C_MUX_PCA9542_ID, "PCA9542A"}
150 #define I2C_MUX_PCA9544_ID	3
151 #define I2C_MUX_PCA9544		{I2C_MUX_PCA9544_ID, "PCA9544A"}
152 #define I2C_MUX_PCA9547_ID	4
153 #define I2C_MUX_PCA9547		{I2C_MUX_PCA9547_ID, "PCA9547A"}
154 #endif
155 
156 #ifndef I2C_SOFT_DECLARATIONS
157 # if defined(CONFIG_MPC8260)
158 #  define I2C_SOFT_DECLARATIONS volatile ioport_t *iop = ioport_addr((immap_t *)CONFIG_SYS_IMMR, I2C_PORT);
159 # elif defined(CONFIG_8xx)
160 #  define I2C_SOFT_DECLARATIONS	volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
161 
162 # elif (defined(CONFIG_AT91RM9200) || \
163 	defined(CONFIG_AT91SAM9260) ||  defined(CONFIG_AT91SAM9261) || \
164 	defined(CONFIG_AT91SAM9263)) && !defined(CONFIG_AT91_LEGACY)
165 #  define I2C_SOFT_DECLARATIONS	at91_pio_t *pio	= (at91_pio_t *) ATMEL_BASE_PIOA;
166 # else
167 #  define I2C_SOFT_DECLARATIONS
168 # endif
169 #endif
170 
171 #ifdef CONFIG_8xx
172 /* Set default value for the I2C bus speed on 8xx. In the
173  * future, we'll define these in all 8xx board config files.
174  */
175 #ifndef	CONFIG_SYS_I2C_SPEED
176 #define	CONFIG_SYS_I2C_SPEED	50000
177 #endif
178 #endif
179 
180 /*
181  * Many boards/controllers/drivers don't support an I2C slave interface so
182  * provide a default slave address for them for use in common code.  A real
183  * value for CONFIG_SYS_I2C_SLAVE should be defined for any board which does
184  * support a slave interface.
185  */
186 #ifndef	CONFIG_SYS_I2C_SLAVE
187 #define	CONFIG_SYS_I2C_SLAVE	0xfe
188 #endif
189 
190 /*
191  * Initialization, must be called once on start up, may be called
192  * repeatedly to change the speed and slave addresses.
193  */
194 void i2c_init(int speed, int slaveaddr);
195 void i2c_init_board(void);
196 #ifdef CONFIG_SYS_I2C_BOARD_LATE_INIT
197 void i2c_board_late_init(void);
198 #endif
199 
200 #ifdef CONFIG_SYS_I2C
201 /*
202  * i2c_get_bus_num:
203  *
204  *  Returns index of currently active I2C bus.  Zero-based.
205  */
206 unsigned int i2c_get_bus_num(void);
207 
208 /*
209  * i2c_set_bus_num:
210  *
211  *  Change the active I2C bus.  Subsequent read/write calls will
212  *  go to this one.
213  *
214  *	bus - bus index, zero based
215  *
216  *	Returns: 0 on success, not 0 on failure
217  *
218  */
219 int i2c_set_bus_num(unsigned int bus);
220 
221 /*
222  * i2c_init_all():
223  *
224  * Initializes all I2C adapters in the system. All i2c_adap structures must
225  * be initialized beforehead with function pointers and data, including
226  * speed and slaveaddr. Returns 0 on success, non-0 on failure.
227  */
228 void i2c_init_all(void);
229 
230 /*
231  * Probe the given I2C chip address.  Returns 0 if a chip responded,
232  * not 0 on failure.
233  */
234 int i2c_probe(uint8_t chip);
235 
236 /*
237  * Read/Write interface:
238  *   chip:    I2C chip address, range 0..127
239  *   addr:    Memory (register) address within the chip
240  *   alen:    Number of bytes to use for addr (typically 1, 2 for larger
241  *              memories, 0 for register type devices with only one
242  *              register)
243  *   buffer:  Where to read/write the data
244  *   len:     How many bytes to read/write
245  *
246  *   Returns: 0 on success, not 0 on failure
247  */
248 int i2c_read(uint8_t chip, unsigned int addr, int alen,
249 				uint8_t *buffer, int len);
250 
251 int i2c_write(uint8_t chip, unsigned int addr, int alen,
252 				uint8_t *buffer, int len);
253 
254 /*
255  * Utility routines to read/write registers.
256  */
257 uint8_t i2c_reg_read(uint8_t addr, uint8_t reg);
258 
259 void i2c_reg_write(uint8_t addr, uint8_t reg, uint8_t val);
260 
261 /*
262  * i2c_set_bus_speed:
263  *
264  *  Change the speed of the active I2C bus
265  *
266  *	speed - bus speed in Hz
267  *
268  *	Returns: new bus speed
269  *
270  */
271 unsigned int i2c_set_bus_speed(unsigned int speed);
272 
273 /*
274  * i2c_get_bus_speed:
275  *
276  *  Returns speed of currently active I2C bus in Hz
277  */
278 
279 unsigned int i2c_get_bus_speed(void);
280 
281 /*
282  * i2c_reloc_fixup:
283  *
284  * Adjusts I2C pointers after U-Boot is relocated to DRAM
285  */
286 void i2c_reloc_fixup(void);
287 #if defined(CONFIG_SYS_I2C_SOFT)
288 void i2c_soft_init(void);
289 void i2c_soft_active(void);
290 void i2c_soft_tristate(void);
291 int i2c_soft_read(void);
292 void i2c_soft_sda(int bit);
293 void i2c_soft_scl(int bit);
294 void i2c_soft_delay(void);
295 #endif
296 #else
297 
298 /*
299  * Probe the given I2C chip address.  Returns 0 if a chip responded,
300  * not 0 on failure.
301  */
302 int i2c_probe(uchar chip);
303 
304 /*
305  * Read/Write interface:
306  *   chip:    I2C chip address, range 0..127
307  *   addr:    Memory (register) address within the chip
308  *   alen:    Number of bytes to use for addr (typically 1, 2 for larger
309  *              memories, 0 for register type devices with only one
310  *              register)
311  *   buffer:  Where to read/write the data
312  *   len:     How many bytes to read/write
313  *
314  *   Returns: 0 on success, not 0 on failure
315  */
316 int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len);
317 int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len);
318 
319 /*
320  * Utility routines to read/write registers.
321  */
322 static inline u8 i2c_reg_read(u8 addr, u8 reg)
323 {
324 	u8 buf;
325 
326 #ifdef CONFIG_8xx
327 	/* MPC8xx needs this.  Maybe one day we can get rid of it. */
328 	i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
329 #endif
330 
331 #ifdef DEBUG
332 	printf("%s: addr=0x%02x, reg=0x%02x\n", __func__, addr, reg);
333 #endif
334 
335 	i2c_read(addr, reg, 1, &buf, 1);
336 
337 	return buf;
338 }
339 
340 static inline void i2c_reg_write(u8 addr, u8 reg, u8 val)
341 {
342 #ifdef CONFIG_8xx
343 	/* MPC8xx needs this.  Maybe one day we can get rid of it. */
344 	i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
345 #endif
346 
347 #ifdef DEBUG
348 	printf("%s: addr=0x%02x, reg=0x%02x, val=0x%02x\n",
349 	       __func__, addr, reg, val);
350 #endif
351 
352 	i2c_write(addr, reg, 1, &val, 1);
353 }
354 
355 /*
356  * Functions for setting the current I2C bus and its speed
357  */
358 
359 /*
360  * i2c_set_bus_num:
361  *
362  *  Change the active I2C bus.  Subsequent read/write calls will
363  *  go to this one.
364  *
365  *	bus - bus index, zero based
366  *
367  *	Returns: 0 on success, not 0 on failure
368  *
369  */
370 int i2c_set_bus_num(unsigned int bus);
371 
372 /*
373  * i2c_get_bus_num:
374  *
375  *  Returns index of currently active I2C bus.  Zero-based.
376  */
377 
378 unsigned int i2c_get_bus_num(void);
379 
380 /*
381  * i2c_set_bus_speed:
382  *
383  *  Change the speed of the active I2C bus
384  *
385  *	speed - bus speed in Hz
386  *
387  *	Returns: 0 on success, not 0 on failure
388  *
389  */
390 int i2c_set_bus_speed(unsigned int);
391 
392 /*
393  * i2c_get_bus_speed:
394  *
395  *  Returns speed of currently active I2C bus in Hz
396  */
397 
398 unsigned int i2c_get_bus_speed(void);
399 #endif /* CONFIG_SYS_I2C */
400 
401 /*
402  * only for backwardcompatibility, should go away if we switched
403  * completely to new multibus support.
404  */
405 #if defined(CONFIG_SYS_I2C) || defined(CONFIG_I2C_MULTI_BUS)
406 # if !defined(CONFIG_SYS_MAX_I2C_BUS)
407 #  define CONFIG_SYS_MAX_I2C_BUS		2
408 # endif
409 # define I2C_MULTI_BUS				0
410 #else
411 # define CONFIG_SYS_MAX_I2C_BUS		1
412 # define I2C_MULTI_BUS				0
413 #endif
414 
415 /* NOTE: These two functions MUST be always_inline to avoid code growth! */
416 static inline unsigned int I2C_GET_BUS(void) __attribute__((always_inline));
417 static inline unsigned int I2C_GET_BUS(void)
418 {
419 	return I2C_MULTI_BUS ? i2c_get_bus_num() : 0;
420 }
421 
422 static inline void I2C_SET_BUS(unsigned int bus) __attribute__((always_inline));
423 static inline void I2C_SET_BUS(unsigned int bus)
424 {
425 	if (I2C_MULTI_BUS)
426 		i2c_set_bus_num(bus);
427 }
428 
429 /* Multi I2C definitions */
430 enum {
431 	I2C_0, I2C_1, I2C_2, I2C_3, I2C_4, I2C_5, I2C_6, I2C_7,
432 	I2C_8, I2C_9, I2C_10,
433 };
434 
435 /* Multi I2C busses handling */
436 #ifdef CONFIG_SOFT_I2C_MULTI_BUS
437 extern int get_multi_scl_pin(void);
438 extern int get_multi_sda_pin(void);
439 extern int multi_i2c_init(void);
440 #endif
441 
442 /**
443  * Get FDT values for i2c bus.
444  *
445  * @param blob  Device tree blbo
446  * @return the number of I2C bus
447  */
448 void board_i2c_init(const void *blob);
449 
450 /**
451  * Find the I2C bus number by given a FDT I2C node.
452  *
453  * @param blob  Device tree blbo
454  * @param node  FDT I2C node to find
455  * @return the number of I2C bus (zero based), or -1 on error
456  */
457 int i2c_get_bus_num_fdt(int node);
458 
459 /**
460  * Reset the I2C bus represented by the given a FDT I2C node.
461  *
462  * @param blob  Device tree blbo
463  * @param node  FDT I2C node to find
464  * @return 0 if port was reset, -1 if not found
465  */
466 int i2c_reset_port_fdt(const void *blob, int node);
467 #endif	/* _I2C_H_ */
468