xref: /openbmc/u-boot/include/i2c.h (revision 70ad375e)
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  * SPDX-License-Identifier:	GPL-2.0+
10  *
11  * The original I2C interface was
12  *   (C) 2000 by Paolo Scaffardi (arsenio@tin.it)
13  *   AIRVENT SAM s.p.a - RIMINI(ITALY)
14  * but has been changed substantially.
15  */
16 
17 #ifndef _I2C_H_
18 #define _I2C_H_
19 
20 /*
21  * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
22  *
23  * The implementation MUST NOT use static or global variables if the
24  * I2C routines are used to read SDRAM configuration information
25  * because this is done before the memories are initialized. Limited
26  * use of stack-based variables are OK (the initial stack size is
27  * limited).
28  *
29  * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
30  */
31 
32 /*
33  * Configuration items.
34  */
35 #define I2C_RXTX_LEN	128	/* maximum tx/rx buffer length */
36 
37 #if !defined(CONFIG_SYS_I2C_MAX_HOPS)
38 /* no muxes used bus = i2c adapters */
39 #define CONFIG_SYS_I2C_DIRECT_BUS	1
40 #define CONFIG_SYS_I2C_MAX_HOPS		0
41 #define CONFIG_SYS_NUM_I2C_BUSES	ll_entry_count(struct i2c_adapter, i2c)
42 #else
43 /* we use i2c muxes */
44 #undef CONFIG_SYS_I2C_DIRECT_BUS
45 #endif
46 
47 /* define the I2C bus number for RTC and DTT if not already done */
48 #if !defined(CONFIG_SYS_RTC_BUS_NUM)
49 #define CONFIG_SYS_RTC_BUS_NUM		0
50 #endif
51 #if !defined(CONFIG_SYS_DTT_BUS_NUM)
52 #define CONFIG_SYS_DTT_BUS_NUM		0
53 #endif
54 #if !defined(CONFIG_SYS_SPD_BUS_NUM)
55 #define CONFIG_SYS_SPD_BUS_NUM		0
56 #endif
57 
58 struct i2c_adapter {
59 	void		(*init)(struct i2c_adapter *adap, int speed,
60 				int slaveaddr);
61 	int		(*probe)(struct i2c_adapter *adap, uint8_t chip);
62 	int		(*read)(struct i2c_adapter *adap, uint8_t chip,
63 				uint addr, int alen, uint8_t *buffer,
64 				int len);
65 	int		(*write)(struct i2c_adapter *adap, uint8_t chip,
66 				uint addr, int alen, uint8_t *buffer,
67 				int len);
68 	uint		(*set_bus_speed)(struct i2c_adapter *adap,
69 				uint speed);
70 	int		speed;
71 	int		waitdelay;
72 	int		slaveaddr;
73 	int		init_done;
74 	int		hwadapnr;
75 	char		*name;
76 };
77 
78 #define U_BOOT_I2C_MKENT_COMPLETE(_init, _probe, _read, _write, \
79 		_set_speed, _speed, _slaveaddr, _hwadapnr, _name) \
80 	{ \
81 		.init		=	_init, \
82 		.probe		=	_probe, \
83 		.read		=	_read, \
84 		.write		=	_write, \
85 		.set_bus_speed	=	_set_speed, \
86 		.speed		=	_speed, \
87 		.slaveaddr	=	_slaveaddr, \
88 		.init_done	=	0, \
89 		.hwadapnr	=	_hwadapnr, \
90 		.name		=	#_name \
91 };
92 
93 #define U_BOOT_I2C_ADAP_COMPLETE(_name, _init, _probe, _read, _write, \
94 			_set_speed, _speed, _slaveaddr, _hwadapnr) \
95 	ll_entry_declare(struct i2c_adapter, _name, i2c) = \
96 	U_BOOT_I2C_MKENT_COMPLETE(_init, _probe, _read, _write, \
97 		 _set_speed, _speed, _slaveaddr, _hwadapnr, _name);
98 
99 struct i2c_adapter *i2c_get_adapter(int index);
100 
101 #ifndef CONFIG_SYS_I2C_DIRECT_BUS
102 struct i2c_mux {
103 	int	id;
104 	char	name[16];
105 };
106 
107 struct i2c_next_hop {
108 	struct i2c_mux		mux;
109 	uint8_t		chip;
110 	uint8_t		channel;
111 };
112 
113 struct i2c_bus_hose {
114 	int	adapter;
115 	struct i2c_next_hop	next_hop[CONFIG_SYS_I2C_MAX_HOPS];
116 };
117 #define I2C_NULL_HOP	{{-1, ""}, 0, 0}
118 extern struct i2c_bus_hose	i2c_bus[];
119 
120 #define I2C_ADAPTER(bus)	i2c_bus[bus].adapter
121 #else
122 #define I2C_ADAPTER(bus)	bus
123 #endif
124 #define	I2C_BUS			gd->cur_i2c_bus
125 
126 #define	I2C_ADAP_NR(bus)	i2c_get_adapter(I2C_ADAPTER(bus))
127 #define	I2C_ADAP		I2C_ADAP_NR(gd->cur_i2c_bus)
128 #define I2C_ADAP_HWNR		(I2C_ADAP->hwadapnr)
129 
130 #ifndef CONFIG_SYS_I2C_DIRECT_BUS
131 #define I2C_MUX_PCA9540_ID	1
132 #define I2C_MUX_PCA9540		{I2C_MUX_PCA9540_ID, "PCA9540B"}
133 #define I2C_MUX_PCA9542_ID	2
134 #define I2C_MUX_PCA9542		{I2C_MUX_PCA9542_ID, "PCA9542A"}
135 #define I2C_MUX_PCA9544_ID	3
136 #define I2C_MUX_PCA9544		{I2C_MUX_PCA9544_ID, "PCA9544A"}
137 #define I2C_MUX_PCA9547_ID	4
138 #define I2C_MUX_PCA9547		{I2C_MUX_PCA9547_ID, "PCA9547A"}
139 #define I2C_MUX_PCA9548_ID	5
140 #define I2C_MUX_PCA9548		{I2C_MUX_PCA9548_ID, "PCA9548"}
141 #endif
142 
143 #ifndef I2C_SOFT_DECLARATIONS
144 # if defined(CONFIG_MPC8260)
145 #  define I2C_SOFT_DECLARATIONS volatile ioport_t *iop = ioport_addr((immap_t *)CONFIG_SYS_IMMR, I2C_PORT);
146 # elif defined(CONFIG_8xx)
147 #  define I2C_SOFT_DECLARATIONS	volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
148 
149 # elif (defined(CONFIG_AT91RM9200) || \
150 	defined(CONFIG_AT91SAM9260) ||  defined(CONFIG_AT91SAM9261) || \
151 	defined(CONFIG_AT91SAM9263))
152 #  define I2C_SOFT_DECLARATIONS	at91_pio_t *pio	= (at91_pio_t *) ATMEL_BASE_PIOA;
153 # else
154 #  define I2C_SOFT_DECLARATIONS
155 # endif
156 #endif
157 
158 #ifdef CONFIG_8xx
159 /* Set default value for the I2C bus speed on 8xx. In the
160  * future, we'll define these in all 8xx board config files.
161  */
162 #ifndef	CONFIG_SYS_I2C_SPEED
163 #define	CONFIG_SYS_I2C_SPEED	50000
164 #endif
165 #endif
166 
167 /*
168  * Many boards/controllers/drivers don't support an I2C slave interface so
169  * provide a default slave address for them for use in common code.  A real
170  * value for CONFIG_SYS_I2C_SLAVE should be defined for any board which does
171  * support a slave interface.
172  */
173 #ifndef	CONFIG_SYS_I2C_SLAVE
174 #define	CONFIG_SYS_I2C_SLAVE	0xfe
175 #endif
176 
177 /*
178  * Initialization, must be called once on start up, may be called
179  * repeatedly to change the speed and slave addresses.
180  */
181 void i2c_init(int speed, int slaveaddr);
182 void i2c_init_board(void);
183 #ifdef CONFIG_SYS_I2C_BOARD_LATE_INIT
184 void i2c_board_late_init(void);
185 #endif
186 
187 #ifdef CONFIG_SYS_I2C
188 /*
189  * i2c_get_bus_num:
190  *
191  *  Returns index of currently active I2C bus.  Zero-based.
192  */
193 unsigned int i2c_get_bus_num(void);
194 
195 /*
196  * i2c_set_bus_num:
197  *
198  *  Change the active I2C bus.  Subsequent read/write calls will
199  *  go to this one.
200  *
201  *	bus - bus index, zero based
202  *
203  *	Returns: 0 on success, not 0 on failure
204  *
205  */
206 int i2c_set_bus_num(unsigned int bus);
207 
208 /*
209  * i2c_init_all():
210  *
211  * Initializes all I2C adapters in the system. All i2c_adap structures must
212  * be initialized beforehead with function pointers and data, including
213  * speed and slaveaddr. Returns 0 on success, non-0 on failure.
214  */
215 void i2c_init_all(void);
216 
217 /*
218  * Probe the given I2C chip address.  Returns 0 if a chip responded,
219  * not 0 on failure.
220  */
221 int i2c_probe(uint8_t chip);
222 
223 /*
224  * Read/Write interface:
225  *   chip:    I2C chip address, range 0..127
226  *   addr:    Memory (register) address within the chip
227  *   alen:    Number of bytes to use for addr (typically 1, 2 for larger
228  *              memories, 0 for register type devices with only one
229  *              register)
230  *   buffer:  Where to read/write the data
231  *   len:     How many bytes to read/write
232  *
233  *   Returns: 0 on success, not 0 on failure
234  */
235 int i2c_read(uint8_t chip, unsigned int addr, int alen,
236 				uint8_t *buffer, int len);
237 
238 int i2c_write(uint8_t chip, unsigned int addr, int alen,
239 				uint8_t *buffer, int len);
240 
241 /*
242  * Utility routines to read/write registers.
243  */
244 uint8_t i2c_reg_read(uint8_t addr, uint8_t reg);
245 
246 void i2c_reg_write(uint8_t addr, uint8_t reg, uint8_t val);
247 
248 /*
249  * i2c_set_bus_speed:
250  *
251  *  Change the speed of the active I2C bus
252  *
253  *	speed - bus speed in Hz
254  *
255  *	Returns: new bus speed
256  *
257  */
258 unsigned int i2c_set_bus_speed(unsigned int speed);
259 
260 /*
261  * i2c_get_bus_speed:
262  *
263  *  Returns speed of currently active I2C bus in Hz
264  */
265 
266 unsigned int i2c_get_bus_speed(void);
267 
268 /*
269  * i2c_reloc_fixup:
270  *
271  * Adjusts I2C pointers after U-Boot is relocated to DRAM
272  */
273 void i2c_reloc_fixup(void);
274 #if defined(CONFIG_SYS_I2C_SOFT)
275 void i2c_soft_init(void);
276 void i2c_soft_active(void);
277 void i2c_soft_tristate(void);
278 int i2c_soft_read(void);
279 void i2c_soft_sda(int bit);
280 void i2c_soft_scl(int bit);
281 void i2c_soft_delay(void);
282 #endif
283 #else
284 
285 /*
286  * Probe the given I2C chip address.  Returns 0 if a chip responded,
287  * not 0 on failure.
288  */
289 int i2c_probe(uchar chip);
290 
291 /*
292  * Read/Write interface:
293  *   chip:    I2C chip address, range 0..127
294  *   addr:    Memory (register) address within the chip
295  *   alen:    Number of bytes to use for addr (typically 1, 2 for larger
296  *              memories, 0 for register type devices with only one
297  *              register)
298  *   buffer:  Where to read/write the data
299  *   len:     How many bytes to read/write
300  *
301  *   Returns: 0 on success, not 0 on failure
302  */
303 int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len);
304 int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len);
305 
306 /*
307  * Utility routines to read/write registers.
308  */
309 static inline u8 i2c_reg_read(u8 addr, u8 reg)
310 {
311 	u8 buf;
312 
313 #ifdef CONFIG_8xx
314 	/* MPC8xx needs this.  Maybe one day we can get rid of it. */
315 	i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
316 #endif
317 
318 #ifdef DEBUG
319 	printf("%s: addr=0x%02x, reg=0x%02x\n", __func__, addr, reg);
320 #endif
321 
322 	i2c_read(addr, reg, 1, &buf, 1);
323 
324 	return buf;
325 }
326 
327 static inline void i2c_reg_write(u8 addr, u8 reg, u8 val)
328 {
329 #ifdef CONFIG_8xx
330 	/* MPC8xx needs this.  Maybe one day we can get rid of it. */
331 	i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
332 #endif
333 
334 #ifdef DEBUG
335 	printf("%s: addr=0x%02x, reg=0x%02x, val=0x%02x\n",
336 	       __func__, addr, reg, val);
337 #endif
338 
339 	i2c_write(addr, reg, 1, &val, 1);
340 }
341 
342 /*
343  * Functions for setting the current I2C bus and its speed
344  */
345 
346 /*
347  * i2c_set_bus_num:
348  *
349  *  Change the active I2C bus.  Subsequent read/write calls will
350  *  go to this one.
351  *
352  *	bus - bus index, zero based
353  *
354  *	Returns: 0 on success, not 0 on failure
355  *
356  */
357 int i2c_set_bus_num(unsigned int bus);
358 
359 /*
360  * i2c_get_bus_num:
361  *
362  *  Returns index of currently active I2C bus.  Zero-based.
363  */
364 
365 unsigned int i2c_get_bus_num(void);
366 
367 /*
368  * i2c_set_bus_speed:
369  *
370  *  Change the speed of the active I2C bus
371  *
372  *	speed - bus speed in Hz
373  *
374  *	Returns: 0 on success, not 0 on failure
375  *
376  */
377 int i2c_set_bus_speed(unsigned int);
378 
379 /*
380  * i2c_get_bus_speed:
381  *
382  *  Returns speed of currently active I2C bus in Hz
383  */
384 
385 unsigned int i2c_get_bus_speed(void);
386 #endif /* CONFIG_SYS_I2C */
387 
388 /*
389  * only for backwardcompatibility, should go away if we switched
390  * completely to new multibus support.
391  */
392 #if defined(CONFIG_SYS_I2C) || defined(CONFIG_I2C_MULTI_BUS)
393 # if !defined(CONFIG_SYS_MAX_I2C_BUS)
394 #  define CONFIG_SYS_MAX_I2C_BUS		2
395 # endif
396 # define I2C_MULTI_BUS				1
397 #else
398 # define CONFIG_SYS_MAX_I2C_BUS		1
399 # define I2C_MULTI_BUS				0
400 #endif
401 
402 /* NOTE: These two functions MUST be always_inline to avoid code growth! */
403 static inline unsigned int I2C_GET_BUS(void) __attribute__((always_inline));
404 static inline unsigned int I2C_GET_BUS(void)
405 {
406 	return I2C_MULTI_BUS ? i2c_get_bus_num() : 0;
407 }
408 
409 static inline void I2C_SET_BUS(unsigned int bus) __attribute__((always_inline));
410 static inline void I2C_SET_BUS(unsigned int bus)
411 {
412 	if (I2C_MULTI_BUS)
413 		i2c_set_bus_num(bus);
414 }
415 
416 /* Multi I2C definitions */
417 enum {
418 	I2C_0, I2C_1, I2C_2, I2C_3, I2C_4, I2C_5, I2C_6, I2C_7,
419 	I2C_8, I2C_9, I2C_10,
420 };
421 
422 /* Multi I2C busses handling */
423 #ifdef CONFIG_SOFT_I2C_MULTI_BUS
424 extern int get_multi_scl_pin(void);
425 extern int get_multi_sda_pin(void);
426 extern int multi_i2c_init(void);
427 #endif
428 
429 /**
430  * Get FDT values for i2c bus.
431  *
432  * @param blob  Device tree blbo
433  * @return the number of I2C bus
434  */
435 void board_i2c_init(const void *blob);
436 
437 /**
438  * Find the I2C bus number by given a FDT I2C node.
439  *
440  * @param blob  Device tree blbo
441  * @param node  FDT I2C node to find
442  * @return the number of I2C bus (zero based), or -1 on error
443  */
444 int i2c_get_bus_num_fdt(int node);
445 
446 /**
447  * Reset the I2C bus represented by the given a FDT I2C node.
448  *
449  * @param blob  Device tree blbo
450  * @param node  FDT I2C node to find
451  * @return 0 if port was reset, -1 if not found
452  */
453 int i2c_reset_port_fdt(const void *blob, int node);
454 #endif	/* _I2C_H_ */
455