xref: /openbmc/u-boot/include/i2c.h (revision 1a05b5f9)
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		slaveaddr;
72 	int		init_done;
73 	int		hwadapnr;
74 	char		*name;
75 };
76 
77 #define U_BOOT_I2C_MKENT_COMPLETE(_init, _probe, _read, _write, \
78 		_set_speed, _speed, _slaveaddr, _hwadapnr, _name) \
79 	{ \
80 		.init		=	_init, \
81 		.probe		=	_probe, \
82 		.read		=	_read, \
83 		.write		=	_write, \
84 		.set_bus_speed	=	_set_speed, \
85 		.speed		=	_speed, \
86 		.slaveaddr	=	_slaveaddr, \
87 		.init_done	=	0, \
88 		.hwadapnr	=	_hwadapnr, \
89 		.name		=	#_name \
90 };
91 
92 #define U_BOOT_I2C_ADAP_COMPLETE(_name, _init, _probe, _read, _write, \
93 			_set_speed, _speed, _slaveaddr, _hwadapnr) \
94 	ll_entry_declare(struct i2c_adapter, _name, i2c) = \
95 	U_BOOT_I2C_MKENT_COMPLETE(_init, _probe, _read, _write, \
96 		 _set_speed, _speed, _slaveaddr, _hwadapnr, _name);
97 
98 struct i2c_adapter *i2c_get_adapter(int index);
99 
100 #ifndef CONFIG_SYS_I2C_DIRECT_BUS
101 struct i2c_mux {
102 	int	id;
103 	char	name[16];
104 };
105 
106 struct i2c_next_hop {
107 	struct i2c_mux		mux;
108 	uint8_t		chip;
109 	uint8_t		channel;
110 };
111 
112 struct i2c_bus_hose {
113 	int	adapter;
114 	struct i2c_next_hop	next_hop[CONFIG_SYS_I2C_MAX_HOPS];
115 };
116 #define I2C_NULL_HOP	{{-1, ""}, 0, 0}
117 extern struct i2c_bus_hose	i2c_bus[];
118 
119 #define I2C_ADAPTER(bus)	i2c_bus[bus].adapter
120 #else
121 #define I2C_ADAPTER(bus)	bus
122 #endif
123 #define	I2C_BUS			gd->cur_i2c_bus
124 
125 #define	I2C_ADAP_NR(bus)	i2c_get_adapter(I2C_ADAPTER(bus))
126 #define	I2C_ADAP		I2C_ADAP_NR(gd->cur_i2c_bus)
127 #define I2C_ADAP_HWNR		(I2C_ADAP->hwadapnr)
128 
129 #ifndef CONFIG_SYS_I2C_DIRECT_BUS
130 #define I2C_MUX_PCA9540_ID	1
131 #define I2C_MUX_PCA9540		{I2C_MUX_PCA9540_ID, "PCA9540B"}
132 #define I2C_MUX_PCA9542_ID	2
133 #define I2C_MUX_PCA9542		{I2C_MUX_PCA9542_ID, "PCA9542A"}
134 #define I2C_MUX_PCA9544_ID	3
135 #define I2C_MUX_PCA9544		{I2C_MUX_PCA9544_ID, "PCA9544A"}
136 #define I2C_MUX_PCA9547_ID	4
137 #define I2C_MUX_PCA9547		{I2C_MUX_PCA9547_ID, "PCA9547A"}
138 #endif
139 
140 #ifndef I2C_SOFT_DECLARATIONS
141 # if defined(CONFIG_MPC8260)
142 #  define I2C_SOFT_DECLARATIONS volatile ioport_t *iop = ioport_addr((immap_t *)CONFIG_SYS_IMMR, I2C_PORT);
143 # elif defined(CONFIG_8xx)
144 #  define I2C_SOFT_DECLARATIONS	volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
145 
146 # elif (defined(CONFIG_AT91RM9200) || \
147 	defined(CONFIG_AT91SAM9260) ||  defined(CONFIG_AT91SAM9261) || \
148 	defined(CONFIG_AT91SAM9263)) && !defined(CONFIG_AT91_LEGACY)
149 #  define I2C_SOFT_DECLARATIONS	at91_pio_t *pio	= (at91_pio_t *) ATMEL_BASE_PIOA;
150 # else
151 #  define I2C_SOFT_DECLARATIONS
152 # endif
153 #endif
154 
155 #ifdef CONFIG_8xx
156 /* Set default value for the I2C bus speed on 8xx. In the
157  * future, we'll define these in all 8xx board config files.
158  */
159 #ifndef	CONFIG_SYS_I2C_SPEED
160 #define	CONFIG_SYS_I2C_SPEED	50000
161 #endif
162 #endif
163 
164 /*
165  * Many boards/controllers/drivers don't support an I2C slave interface so
166  * provide a default slave address for them for use in common code.  A real
167  * value for CONFIG_SYS_I2C_SLAVE should be defined for any board which does
168  * support a slave interface.
169  */
170 #ifndef	CONFIG_SYS_I2C_SLAVE
171 #define	CONFIG_SYS_I2C_SLAVE	0xfe
172 #endif
173 
174 /*
175  * Initialization, must be called once on start up, may be called
176  * repeatedly to change the speed and slave addresses.
177  */
178 void i2c_init(int speed, int slaveaddr);
179 void i2c_init_board(void);
180 #ifdef CONFIG_SYS_I2C_BOARD_LATE_INIT
181 void i2c_board_late_init(void);
182 #endif
183 
184 #ifdef CONFIG_SYS_I2C
185 /*
186  * i2c_get_bus_num:
187  *
188  *  Returns index of currently active I2C bus.  Zero-based.
189  */
190 unsigned int i2c_get_bus_num(void);
191 
192 /*
193  * i2c_set_bus_num:
194  *
195  *  Change the active I2C bus.  Subsequent read/write calls will
196  *  go to this one.
197  *
198  *	bus - bus index, zero based
199  *
200  *	Returns: 0 on success, not 0 on failure
201  *
202  */
203 int i2c_set_bus_num(unsigned int bus);
204 
205 /*
206  * i2c_init_all():
207  *
208  * Initializes all I2C adapters in the system. All i2c_adap structures must
209  * be initialized beforehead with function pointers and data, including
210  * speed and slaveaddr. Returns 0 on success, non-0 on failure.
211  */
212 void i2c_init_all(void);
213 
214 /*
215  * Probe the given I2C chip address.  Returns 0 if a chip responded,
216  * not 0 on failure.
217  */
218 int i2c_probe(uint8_t chip);
219 
220 /*
221  * Read/Write interface:
222  *   chip:    I2C chip address, range 0..127
223  *   addr:    Memory (register) address within the chip
224  *   alen:    Number of bytes to use for addr (typically 1, 2 for larger
225  *              memories, 0 for register type devices with only one
226  *              register)
227  *   buffer:  Where to read/write the data
228  *   len:     How many bytes to read/write
229  *
230  *   Returns: 0 on success, not 0 on failure
231  */
232 int i2c_read(uint8_t chip, unsigned int addr, int alen,
233 				uint8_t *buffer, int len);
234 
235 int i2c_write(uint8_t chip, unsigned int addr, int alen,
236 				uint8_t *buffer, int len);
237 
238 /*
239  * Utility routines to read/write registers.
240  */
241 uint8_t i2c_reg_read(uint8_t addr, uint8_t reg);
242 
243 void i2c_reg_write(uint8_t addr, uint8_t reg, uint8_t val);
244 
245 /*
246  * i2c_set_bus_speed:
247  *
248  *  Change the speed of the active I2C bus
249  *
250  *	speed - bus speed in Hz
251  *
252  *	Returns: new bus speed
253  *
254  */
255 unsigned int i2c_set_bus_speed(unsigned int speed);
256 
257 /*
258  * i2c_get_bus_speed:
259  *
260  *  Returns speed of currently active I2C bus in Hz
261  */
262 
263 unsigned int i2c_get_bus_speed(void);
264 
265 /*
266  * i2c_reloc_fixup:
267  *
268  * Adjusts I2C pointers after U-Boot is relocated to DRAM
269  */
270 void i2c_reloc_fixup(void);
271 #if defined(CONFIG_SYS_I2C_SOFT)
272 void i2c_soft_init(void);
273 void i2c_soft_active(void);
274 void i2c_soft_tristate(void);
275 int i2c_soft_read(void);
276 void i2c_soft_sda(int bit);
277 void i2c_soft_scl(int bit);
278 void i2c_soft_delay(void);
279 #endif
280 #else
281 
282 /*
283  * Probe the given I2C chip address.  Returns 0 if a chip responded,
284  * not 0 on failure.
285  */
286 int i2c_probe(uchar chip);
287 
288 /*
289  * Read/Write interface:
290  *   chip:    I2C chip address, range 0..127
291  *   addr:    Memory (register) address within the chip
292  *   alen:    Number of bytes to use for addr (typically 1, 2 for larger
293  *              memories, 0 for register type devices with only one
294  *              register)
295  *   buffer:  Where to read/write the data
296  *   len:     How many bytes to read/write
297  *
298  *   Returns: 0 on success, not 0 on failure
299  */
300 int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len);
301 int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len);
302 
303 /*
304  * Utility routines to read/write registers.
305  */
306 static inline u8 i2c_reg_read(u8 addr, u8 reg)
307 {
308 	u8 buf;
309 
310 #ifdef CONFIG_8xx
311 	/* MPC8xx needs this.  Maybe one day we can get rid of it. */
312 	i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
313 #endif
314 
315 #ifdef DEBUG
316 	printf("%s: addr=0x%02x, reg=0x%02x\n", __func__, addr, reg);
317 #endif
318 
319 	i2c_read(addr, reg, 1, &buf, 1);
320 
321 	return buf;
322 }
323 
324 static inline void i2c_reg_write(u8 addr, u8 reg, u8 val)
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, val=0x%02x\n",
333 	       __func__, addr, reg, val);
334 #endif
335 
336 	i2c_write(addr, reg, 1, &val, 1);
337 }
338 
339 /*
340  * Functions for setting the current I2C bus and its speed
341  */
342 
343 /*
344  * i2c_set_bus_num:
345  *
346  *  Change the active I2C bus.  Subsequent read/write calls will
347  *  go to this one.
348  *
349  *	bus - bus index, zero based
350  *
351  *	Returns: 0 on success, not 0 on failure
352  *
353  */
354 int i2c_set_bus_num(unsigned int bus);
355 
356 /*
357  * i2c_get_bus_num:
358  *
359  *  Returns index of currently active I2C bus.  Zero-based.
360  */
361 
362 unsigned int i2c_get_bus_num(void);
363 
364 /*
365  * i2c_set_bus_speed:
366  *
367  *  Change the speed of the active I2C bus
368  *
369  *	speed - bus speed in Hz
370  *
371  *	Returns: 0 on success, not 0 on failure
372  *
373  */
374 int i2c_set_bus_speed(unsigned int);
375 
376 /*
377  * i2c_get_bus_speed:
378  *
379  *  Returns speed of currently active I2C bus in Hz
380  */
381 
382 unsigned int i2c_get_bus_speed(void);
383 #endif /* CONFIG_SYS_I2C */
384 
385 /*
386  * only for backwardcompatibility, should go away if we switched
387  * completely to new multibus support.
388  */
389 #if defined(CONFIG_SYS_I2C) || defined(CONFIG_I2C_MULTI_BUS)
390 # if !defined(CONFIG_SYS_MAX_I2C_BUS)
391 #  define CONFIG_SYS_MAX_I2C_BUS		2
392 # endif
393 # define I2C_MULTI_BUS				1
394 #else
395 # define CONFIG_SYS_MAX_I2C_BUS		1
396 # define I2C_MULTI_BUS				0
397 #endif
398 
399 /* NOTE: These two functions MUST be always_inline to avoid code growth! */
400 static inline unsigned int I2C_GET_BUS(void) __attribute__((always_inline));
401 static inline unsigned int I2C_GET_BUS(void)
402 {
403 	return I2C_MULTI_BUS ? i2c_get_bus_num() : 0;
404 }
405 
406 static inline void I2C_SET_BUS(unsigned int bus) __attribute__((always_inline));
407 static inline void I2C_SET_BUS(unsigned int bus)
408 {
409 	if (I2C_MULTI_BUS)
410 		i2c_set_bus_num(bus);
411 }
412 
413 /* Multi I2C definitions */
414 enum {
415 	I2C_0, I2C_1, I2C_2, I2C_3, I2C_4, I2C_5, I2C_6, I2C_7,
416 	I2C_8, I2C_9, I2C_10,
417 };
418 
419 /* Multi I2C busses handling */
420 #ifdef CONFIG_SOFT_I2C_MULTI_BUS
421 extern int get_multi_scl_pin(void);
422 extern int get_multi_sda_pin(void);
423 extern int multi_i2c_init(void);
424 #endif
425 
426 /**
427  * Get FDT values for i2c bus.
428  *
429  * @param blob  Device tree blbo
430  * @return the number of I2C bus
431  */
432 void board_i2c_init(const void *blob);
433 
434 /**
435  * Find the I2C bus number by given a FDT I2C node.
436  *
437  * @param blob  Device tree blbo
438  * @param node  FDT I2C node to find
439  * @return the number of I2C bus (zero based), or -1 on error
440  */
441 int i2c_get_bus_num_fdt(int node);
442 
443 /**
444  * Reset the I2C bus represented by the given a FDT I2C node.
445  *
446  * @param blob  Device tree blbo
447  * @param node  FDT I2C node to find
448  * @return 0 if port was reset, -1 if not found
449  */
450 int i2c_reset_port_fdt(const void *blob, int node);
451 #endif	/* _I2C_H_ */
452