xref: /openbmc/u-boot/include/i2c.h (revision 4611d5ba)
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 #define I2C_MUX_PCA9548_ID	5
139 #define I2C_MUX_PCA9548		{I2C_MUX_PCA9548_ID, "PCA9548"}
140 #endif
141 
142 #ifndef I2C_SOFT_DECLARATIONS
143 # if defined(CONFIG_MPC8260)
144 #  define I2C_SOFT_DECLARATIONS volatile ioport_t *iop = ioport_addr((immap_t *)CONFIG_SYS_IMMR, I2C_PORT);
145 # elif defined(CONFIG_8xx)
146 #  define I2C_SOFT_DECLARATIONS	volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
147 
148 # elif (defined(CONFIG_AT91RM9200) || \
149 	defined(CONFIG_AT91SAM9260) ||  defined(CONFIG_AT91SAM9261) || \
150 	defined(CONFIG_AT91SAM9263)) && !defined(CONFIG_AT91_LEGACY)
151 #  define I2C_SOFT_DECLARATIONS	at91_pio_t *pio	= (at91_pio_t *) ATMEL_BASE_PIOA;
152 # else
153 #  define I2C_SOFT_DECLARATIONS
154 # endif
155 #endif
156 
157 #ifdef CONFIG_8xx
158 /* Set default value for the I2C bus speed on 8xx. In the
159  * future, we'll define these in all 8xx board config files.
160  */
161 #ifndef	CONFIG_SYS_I2C_SPEED
162 #define	CONFIG_SYS_I2C_SPEED	50000
163 #endif
164 #endif
165 
166 /*
167  * Many boards/controllers/drivers don't support an I2C slave interface so
168  * provide a default slave address for them for use in common code.  A real
169  * value for CONFIG_SYS_I2C_SLAVE should be defined for any board which does
170  * support a slave interface.
171  */
172 #ifndef	CONFIG_SYS_I2C_SLAVE
173 #define	CONFIG_SYS_I2C_SLAVE	0xfe
174 #endif
175 
176 /*
177  * Initialization, must be called once on start up, may be called
178  * repeatedly to change the speed and slave addresses.
179  */
180 void i2c_init(int speed, int slaveaddr);
181 void i2c_init_board(void);
182 #ifdef CONFIG_SYS_I2C_BOARD_LATE_INIT
183 void i2c_board_late_init(void);
184 #endif
185 
186 #ifdef CONFIG_SYS_I2C
187 /*
188  * i2c_get_bus_num:
189  *
190  *  Returns index of currently active I2C bus.  Zero-based.
191  */
192 unsigned int i2c_get_bus_num(void);
193 
194 /*
195  * i2c_set_bus_num:
196  *
197  *  Change the active I2C bus.  Subsequent read/write calls will
198  *  go to this one.
199  *
200  *	bus - bus index, zero based
201  *
202  *	Returns: 0 on success, not 0 on failure
203  *
204  */
205 int i2c_set_bus_num(unsigned int bus);
206 
207 /*
208  * i2c_init_all():
209  *
210  * Initializes all I2C adapters in the system. All i2c_adap structures must
211  * be initialized beforehead with function pointers and data, including
212  * speed and slaveaddr. Returns 0 on success, non-0 on failure.
213  */
214 void i2c_init_all(void);
215 
216 /*
217  * Probe the given I2C chip address.  Returns 0 if a chip responded,
218  * not 0 on failure.
219  */
220 int i2c_probe(uint8_t chip);
221 
222 /*
223  * Read/Write interface:
224  *   chip:    I2C chip address, range 0..127
225  *   addr:    Memory (register) address within the chip
226  *   alen:    Number of bytes to use for addr (typically 1, 2 for larger
227  *              memories, 0 for register type devices with only one
228  *              register)
229  *   buffer:  Where to read/write the data
230  *   len:     How many bytes to read/write
231  *
232  *   Returns: 0 on success, not 0 on failure
233  */
234 int i2c_read(uint8_t chip, unsigned int addr, int alen,
235 				uint8_t *buffer, int len);
236 
237 int i2c_write(uint8_t chip, unsigned int addr, int alen,
238 				uint8_t *buffer, int len);
239 
240 /*
241  * Utility routines to read/write registers.
242  */
243 uint8_t i2c_reg_read(uint8_t addr, uint8_t reg);
244 
245 void i2c_reg_write(uint8_t addr, uint8_t reg, uint8_t val);
246 
247 /*
248  * i2c_set_bus_speed:
249  *
250  *  Change the speed of the active I2C bus
251  *
252  *	speed - bus speed in Hz
253  *
254  *	Returns: new bus speed
255  *
256  */
257 unsigned int i2c_set_bus_speed(unsigned int speed);
258 
259 /*
260  * i2c_get_bus_speed:
261  *
262  *  Returns speed of currently active I2C bus in Hz
263  */
264 
265 unsigned int i2c_get_bus_speed(void);
266 
267 /*
268  * i2c_reloc_fixup:
269  *
270  * Adjusts I2C pointers after U-Boot is relocated to DRAM
271  */
272 void i2c_reloc_fixup(void);
273 #if defined(CONFIG_SYS_I2C_SOFT)
274 void i2c_soft_init(void);
275 void i2c_soft_active(void);
276 void i2c_soft_tristate(void);
277 int i2c_soft_read(void);
278 void i2c_soft_sda(int bit);
279 void i2c_soft_scl(int bit);
280 void i2c_soft_delay(void);
281 #endif
282 #else
283 
284 /*
285  * Probe the given I2C chip address.  Returns 0 if a chip responded,
286  * not 0 on failure.
287  */
288 int i2c_probe(uchar chip);
289 
290 /*
291  * Read/Write interface:
292  *   chip:    I2C chip address, range 0..127
293  *   addr:    Memory (register) address within the chip
294  *   alen:    Number of bytes to use for addr (typically 1, 2 for larger
295  *              memories, 0 for register type devices with only one
296  *              register)
297  *   buffer:  Where to read/write the data
298  *   len:     How many bytes to read/write
299  *
300  *   Returns: 0 on success, not 0 on failure
301  */
302 int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len);
303 int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len);
304 
305 /*
306  * Utility routines to read/write registers.
307  */
308 static inline u8 i2c_reg_read(u8 addr, u8 reg)
309 {
310 	u8 buf;
311 
312 #ifdef CONFIG_8xx
313 	/* MPC8xx needs this.  Maybe one day we can get rid of it. */
314 	i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
315 #endif
316 
317 #ifdef DEBUG
318 	printf("%s: addr=0x%02x, reg=0x%02x\n", __func__, addr, reg);
319 #endif
320 
321 	i2c_read(addr, reg, 1, &buf, 1);
322 
323 	return buf;
324 }
325 
326 static inline void i2c_reg_write(u8 addr, u8 reg, u8 val)
327 {
328 #ifdef CONFIG_8xx
329 	/* MPC8xx needs this.  Maybe one day we can get rid of it. */
330 	i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
331 #endif
332 
333 #ifdef DEBUG
334 	printf("%s: addr=0x%02x, reg=0x%02x, val=0x%02x\n",
335 	       __func__, addr, reg, val);
336 #endif
337 
338 	i2c_write(addr, reg, 1, &val, 1);
339 }
340 
341 /*
342  * Functions for setting the current I2C bus and its speed
343  */
344 
345 /*
346  * i2c_set_bus_num:
347  *
348  *  Change the active I2C bus.  Subsequent read/write calls will
349  *  go to this one.
350  *
351  *	bus - bus index, zero based
352  *
353  *	Returns: 0 on success, not 0 on failure
354  *
355  */
356 int i2c_set_bus_num(unsigned int bus);
357 
358 /*
359  * i2c_get_bus_num:
360  *
361  *  Returns index of currently active I2C bus.  Zero-based.
362  */
363 
364 unsigned int i2c_get_bus_num(void);
365 
366 /*
367  * i2c_set_bus_speed:
368  *
369  *  Change the speed of the active I2C bus
370  *
371  *	speed - bus speed in Hz
372  *
373  *	Returns: 0 on success, not 0 on failure
374  *
375  */
376 int i2c_set_bus_speed(unsigned int);
377 
378 /*
379  * i2c_get_bus_speed:
380  *
381  *  Returns speed of currently active I2C bus in Hz
382  */
383 
384 unsigned int i2c_get_bus_speed(void);
385 #endif /* CONFIG_SYS_I2C */
386 
387 /*
388  * only for backwardcompatibility, should go away if we switched
389  * completely to new multibus support.
390  */
391 #if defined(CONFIG_SYS_I2C) || defined(CONFIG_I2C_MULTI_BUS)
392 # if !defined(CONFIG_SYS_MAX_I2C_BUS)
393 #  define CONFIG_SYS_MAX_I2C_BUS		2
394 # endif
395 # define I2C_MULTI_BUS				1
396 #else
397 # define CONFIG_SYS_MAX_I2C_BUS		1
398 # define I2C_MULTI_BUS				0
399 #endif
400 
401 /* NOTE: These two functions MUST be always_inline to avoid code growth! */
402 static inline unsigned int I2C_GET_BUS(void) __attribute__((always_inline));
403 static inline unsigned int I2C_GET_BUS(void)
404 {
405 	return I2C_MULTI_BUS ? i2c_get_bus_num() : 0;
406 }
407 
408 static inline void I2C_SET_BUS(unsigned int bus) __attribute__((always_inline));
409 static inline void I2C_SET_BUS(unsigned int bus)
410 {
411 	if (I2C_MULTI_BUS)
412 		i2c_set_bus_num(bus);
413 }
414 
415 /* Multi I2C definitions */
416 enum {
417 	I2C_0, I2C_1, I2C_2, I2C_3, I2C_4, I2C_5, I2C_6, I2C_7,
418 	I2C_8, I2C_9, I2C_10,
419 };
420 
421 /* Multi I2C busses handling */
422 #ifdef CONFIG_SOFT_I2C_MULTI_BUS
423 extern int get_multi_scl_pin(void);
424 extern int get_multi_sda_pin(void);
425 extern int multi_i2c_init(void);
426 #endif
427 
428 /**
429  * Get FDT values for i2c bus.
430  *
431  * @param blob  Device tree blbo
432  * @return the number of I2C bus
433  */
434 void board_i2c_init(const void *blob);
435 
436 /**
437  * Find the I2C bus number by given a FDT I2C node.
438  *
439  * @param blob  Device tree blbo
440  * @param node  FDT I2C node to find
441  * @return the number of I2C bus (zero based), or -1 on error
442  */
443 int i2c_get_bus_num_fdt(int node);
444 
445 /**
446  * Reset the I2C bus represented by the given a FDT I2C node.
447  *
448  * @param blob  Device tree blbo
449  * @param node  FDT I2C node to find
450  * @return 0 if port was reset, -1 if not found
451  */
452 int i2c_reset_port_fdt(const void *blob, int node);
453 #endif	/* _I2C_H_ */
454