xref: /openbmc/u-boot/include/i2c.h (revision a3b36c84)
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  * For now there are essentially two parts to this file - driver model
22  * here at the top, and the older code below (with CONFIG_SYS_I2C being
23  * most recent). The plan is to migrate everything to driver model.
24  * The driver model structures and API are separate as they are different
25  * enough as to be incompatible for compilation purposes.
26  */
27 
28 enum dm_i2c_chip_flags {
29 	DM_I2C_CHIP_10BIT	= 1 << 0, /* Use 10-bit addressing */
30 	DM_I2C_CHIP_RD_ADDRESS	= 1 << 1, /* Send address for each read byte */
31 	DM_I2C_CHIP_WR_ADDRESS	= 1 << 2, /* Send address for each write byte */
32 };
33 
34 struct udevice;
35 /**
36  * struct dm_i2c_chip - information about an i2c chip
37  *
38  * An I2C chip is a device on the I2C bus. It sits at a particular address
39  * and normally supports 7-bit or 10-bit addressing.
40  *
41  * To obtain this structure, use dev_get_parent_platdata(dev) where dev is
42  * the chip to examine.
43  *
44  * @chip_addr:	Chip address on bus
45  * @offset_len: Length of offset in bytes. A single byte offset can
46  *		represent up to 256 bytes. A value larger than 1 may be
47  *		needed for larger devices.
48  * @flags:	Flags for this chip (dm_i2c_chip_flags)
49  * @emul: Emulator for this chip address (only used for emulation)
50  */
51 struct dm_i2c_chip {
52 	uint chip_addr;
53 	uint offset_len;
54 	uint flags;
55 #ifdef CONFIG_SANDBOX
56 	struct udevice *emul;
57 	bool test_mode;
58 #endif
59 };
60 
61 /**
62  * struct dm_i2c_bus- information about an i2c bus
63  *
64  * An I2C bus contains 0 or more chips on it, each at its own address. The
65  * bus can operate at different speeds (measured in Hz, typically 100KHz
66  * or 400KHz).
67  *
68  * To obtain this structure, use dev_get_uclass_priv(bus) where bus is the
69  * I2C bus udevice.
70  *
71  * @speed_hz: Bus speed in hertz (typically 100000)
72  */
73 struct dm_i2c_bus {
74 	int speed_hz;
75 };
76 
77 /*
78  * Not all of these flags are implemented in the U-Boot API
79  */
80 enum dm_i2c_msg_flags {
81 	I2C_M_TEN		= 0x0010, /* ten-bit chip address */
82 	I2C_M_RD		= 0x0001, /* read data, from slave to master */
83 	I2C_M_STOP		= 0x8000, /* send stop after this message */
84 	I2C_M_NOSTART		= 0x4000, /* no start before this message */
85 	I2C_M_REV_DIR_ADDR	= 0x2000, /* invert polarity of R/W bit */
86 	I2C_M_IGNORE_NAK	= 0x1000, /* continue after NAK */
87 	I2C_M_NO_RD_ACK		= 0x0800, /* skip the Ack bit on reads */
88 	I2C_M_RECV_LEN		= 0x0400, /* length is first received byte */
89 };
90 
91 /**
92  * struct i2c_msg - an I2C message
93  *
94  * @addr:	Slave address
95  * @flags:	Flags (see enum dm_i2c_msg_flags)
96  * @len:	Length of buffer in bytes, may be 0 for a probe
97  * @buf:	Buffer to send/receive, or NULL if no data
98  */
99 struct i2c_msg {
100 	uint addr;
101 	uint flags;
102 	uint len;
103 	u8 *buf;
104 };
105 
106 /**
107  * struct i2c_msg_list - a list of I2C messages
108  *
109  * This is called i2c_rdwr_ioctl_data in Linux but the name does not seem
110  * appropriate in U-Boot.
111  *
112  * @msg:	Pointer to i2c_msg array
113  * @nmsgs:	Number of elements in the array
114  */
115 struct i2c_msg_list {
116 	struct i2c_msg *msgs;
117 	uint nmsgs;
118 };
119 
120 /**
121  * dm_i2c_read() - read bytes from an I2C chip
122  *
123  * To obtain an I2C device (called a 'chip') given the I2C bus address you
124  * can use i2c_get_chip(). To obtain a bus by bus number use
125  * uclass_get_device_by_seq(UCLASS_I2C, <bus number>).
126  *
127  * To set the address length of a devce use i2c_set_addr_len(). It
128  * defaults to 1.
129  *
130  * @dev:	Chip to read from
131  * @offset:	Offset within chip to start reading
132  * @buffer:	Place to put data
133  * @len:	Number of bytes to read
134  *
135  * @return 0 on success, -ve on failure
136  */
137 int dm_i2c_read(struct udevice *dev, uint offset, uint8_t *buffer, int len);
138 
139 /**
140  * dm_i2c_write() - write bytes to an I2C chip
141  *
142  * See notes for dm_i2c_read() above.
143  *
144  * @dev:	Chip to write to
145  * @offset:	Offset within chip to start writing
146  * @buffer:	Buffer containing data to write
147  * @len:	Number of bytes to write
148  *
149  * @return 0 on success, -ve on failure
150  */
151 int dm_i2c_write(struct udevice *dev, uint offset, const uint8_t *buffer,
152 		 int len);
153 
154 /**
155  * dm_i2c_probe() - probe a particular chip address
156  *
157  * This can be useful to check for the existence of a chip on the bus.
158  * It is typically implemented by writing the chip address to the bus
159  * and checking that the chip replies with an ACK.
160  *
161  * @bus:	Bus to probe
162  * @chip_addr:	7-bit address to probe (10-bit and others are not supported)
163  * @chip_flags:	Flags for the probe (see enum dm_i2c_chip_flags)
164  * @devp:	Returns the device found, or NULL if none
165  * @return 0 if a chip was found at that address, -ve if not
166  */
167 int dm_i2c_probe(struct udevice *bus, uint chip_addr, uint chip_flags,
168 		 struct udevice **devp);
169 
170 /**
171  * dm_i2c_reg_read() - Read a value from an I2C register
172  *
173  * This reads a single value from the given address in an I2C chip
174  *
175  * @dev:	Device to use for transfer
176  * @addr:	Address to read from
177  * @return value read, or -ve on error
178  */
179 int dm_i2c_reg_read(struct udevice *dev, uint offset);
180 
181 /**
182  * dm_i2c_reg_write() - Write a value to an I2C register
183  *
184  * This writes a single value to the given address in an I2C chip
185  *
186  * @dev:	Device to use for transfer
187  * @addr:	Address to write to
188  * @val:	Value to write (normally a byte)
189  * @return 0 on success, -ve on error
190  */
191 int dm_i2c_reg_write(struct udevice *dev, uint offset, unsigned int val);
192 
193 /**
194  * dm_i2c_xfer() - Transfer messages over I2C
195  *
196  * This transfers a raw message. It is best to use dm_i2c_reg_read/write()
197  * instead.
198  *
199  * @dev:	Device to use for transfer
200  * @msg:	List of messages to transfer
201  * @nmsgs:	Number of messages to transfer
202  * @return 0 on success, -ve on error
203  */
204 int dm_i2c_xfer(struct udevice *dev, struct i2c_msg *msg, int nmsgs);
205 
206 /**
207  * dm_i2c_set_bus_speed() - set the speed of a bus
208  *
209  * @bus:	Bus to adjust
210  * @speed:	Requested speed in Hz
211  * @return 0 if OK, -EINVAL for invalid values
212  */
213 int dm_i2c_set_bus_speed(struct udevice *bus, unsigned int speed);
214 
215 /**
216  * dm_i2c_get_bus_speed() - get the speed of a bus
217  *
218  * @bus:	Bus to check
219  * @return speed of selected I2C bus in Hz, -ve on error
220  */
221 int dm_i2c_get_bus_speed(struct udevice *bus);
222 
223 /**
224  * i2c_set_chip_flags() - set flags for a chip
225  *
226  * Typically addresses are 7 bits, but for 10-bit addresses you should set
227  * flags to DM_I2C_CHIP_10BIT. All accesses will then use 10-bit addressing.
228  *
229  * @dev:	Chip to adjust
230  * @flags:	New flags
231  * @return 0 if OK, -EINVAL if value is unsupported, other -ve value on error
232  */
233 int i2c_set_chip_flags(struct udevice *dev, uint flags);
234 
235 /**
236  * i2c_get_chip_flags() - get flags for a chip
237  *
238  * @dev:	Chip to check
239  * @flagsp:	Place to put flags
240  * @return 0 if OK, other -ve value on error
241  */
242 int i2c_get_chip_flags(struct udevice *dev, uint *flagsp);
243 
244 /**
245  * i2c_set_offset_len() - set the offset length for a chip
246  *
247  * The offset used to access a chip may be up to 4 bytes long. Typically it
248  * is only 1 byte, which is enough for chips with 256 bytes of memory or
249  * registers. The default value is 1, but you can call this function to
250  * change it.
251  *
252  * @offset_len:	New offset length value (typically 1 or 2)
253  */
254 int i2c_set_chip_offset_len(struct udevice *dev, uint offset_len);
255 
256 /**
257  * i2c_get_offset_len() - get the offset length for a chip
258  *
259  * @return:	Current offset length value (typically 1 or 2)
260  */
261 int i2c_get_chip_offset_len(struct udevice *dev);
262 
263 /**
264  * i2c_deblock() - recover a bus that is in an unknown state
265  *
266  * See the deblock() method in 'struct dm_i2c_ops' for full information
267  *
268  * @bus:	Bus to recover
269  * @return 0 if OK, -ve on error
270  */
271 int i2c_deblock(struct udevice *bus);
272 
273 #ifdef CONFIG_DM_I2C_COMPAT
274 /**
275  * i2c_probe() - Compatibility function for driver model
276  *
277  * Calls dm_i2c_probe() on the current bus
278  */
279 int i2c_probe(uint8_t chip_addr);
280 
281 /**
282  * i2c_read() - Compatibility function for driver model
283  *
284  * Calls dm_i2c_read() with the device corresponding to @chip_addr, and offset
285  * set to @addr. @alen must match the current setting for the device.
286  */
287 int i2c_read(uint8_t chip_addr, unsigned int addr, int alen, uint8_t *buffer,
288 	     int len);
289 
290 /**
291  * i2c_write() - Compatibility function for driver model
292  *
293  * Calls dm_i2c_write() with the device corresponding to @chip_addr, and offset
294  * set to @addr. @alen must match the current setting for the device.
295  */
296 int i2c_write(uint8_t chip_addr, unsigned int addr, int alen, uint8_t *buffer,
297 	      int len);
298 
299 /**
300  * i2c_get_bus_num_fdt() - Compatibility function for driver model
301  *
302  * @return the bus number associated with the given device tree node
303  */
304 int i2c_get_bus_num_fdt(int node);
305 
306 /**
307  * i2c_get_bus_num() - Compatibility function for driver model
308  *
309  * @return the 'current' bus number
310  */
311 unsigned int i2c_get_bus_num(void);
312 
313 /**
314  * i2c_set_bus_num() - Compatibility function for driver model
315  *
316  * Sets the 'current' bus
317  */
318 int i2c_set_bus_num(unsigned int bus);
319 
320 static inline void I2C_SET_BUS(unsigned int bus)
321 {
322 	i2c_set_bus_num(bus);
323 }
324 
325 static inline unsigned int I2C_GET_BUS(void)
326 {
327 	return i2c_get_bus_num();
328 }
329 
330 /**
331  * i2c_init() - Compatibility function for driver model
332  *
333  * This function does nothing.
334  */
335 void i2c_init(int speed, int slaveaddr);
336 
337 /**
338  * board_i2c_init() - Compatibility function for driver model
339  *
340  * @param blob  Device tree blbo
341  * @return the number of I2C bus
342  */
343 void board_i2c_init(const void *blob);
344 
345 /*
346  * Compatibility functions for driver model.
347  */
348 uint8_t i2c_reg_read(uint8_t addr, uint8_t reg);
349 void i2c_reg_write(uint8_t addr, uint8_t reg, uint8_t val);
350 
351 #endif
352 
353 /**
354  * struct dm_i2c_ops - driver operations for I2C uclass
355  *
356  * Drivers should support these operations unless otherwise noted. These
357  * operations are intended to be used by uclass code, not directly from
358  * other code.
359  */
360 struct dm_i2c_ops {
361 	/**
362 	 * xfer() - transfer a list of I2C messages
363 	 *
364 	 * @bus:	Bus to read from
365 	 * @msg:	List of messages to transfer
366 	 * @nmsgs:	Number of messages in the list
367 	 * @return 0 if OK, -EREMOTEIO if the slave did not ACK a byte,
368 	 *	-ECOMM if the speed cannot be supported, -EPROTO if the chip
369 	 *	flags cannot be supported, other -ve value on some other error
370 	 */
371 	int (*xfer)(struct udevice *bus, struct i2c_msg *msg, int nmsgs);
372 
373 	/**
374 	 * probe_chip() - probe for the presense of a chip address
375 	 *
376 	 * This function is optional. If omitted, the uclass will send a zero
377 	 * length message instead.
378 	 *
379 	 * @bus:	Bus to probe
380 	 * @chip_addr:	Chip address to probe
381 	 * @chip_flags:	Probe flags (enum dm_i2c_chip_flags)
382 	 * @return 0 if chip was found, -EREMOTEIO if not, -ENOSYS to fall back
383 	 * to default probem other -ve value on error
384 	 */
385 	int (*probe_chip)(struct udevice *bus, uint chip_addr, uint chip_flags);
386 
387 	/**
388 	 * set_bus_speed() - set the speed of a bus (optional)
389 	 *
390 	 * The bus speed value will be updated by the uclass if this function
391 	 * does not return an error. This method is optional - if it is not
392 	 * provided then the driver can read the speed from
393 	 * dev_get_uclass_priv(bus)->speed_hz
394 	 *
395 	 * @bus:	Bus to adjust
396 	 * @speed:	Requested speed in Hz
397 	 * @return 0 if OK, -EINVAL for invalid values
398 	 */
399 	int (*set_bus_speed)(struct udevice *bus, unsigned int speed);
400 
401 	/**
402 	 * get_bus_speed() - get the speed of a bus (optional)
403 	 *
404 	 * Normally this can be provided by the uclass, but if you want your
405 	 * driver to check the bus speed by looking at the hardware, you can
406 	 * implement that here. This method is optional. This method would
407 	 * normally be expected to return dev_get_uclass_priv(bus)->speed_hz.
408 	 *
409 	 * @bus:	Bus to check
410 	 * @return speed of selected I2C bus in Hz, -ve on error
411 	 */
412 	int (*get_bus_speed)(struct udevice *bus);
413 
414 	/**
415 	 * set_flags() - set the flags for a chip (optional)
416 	 *
417 	 * This is generally implemented by the uclass, but drivers can
418 	 * check the value to ensure that unsupported options are not used.
419 	 * This method is optional. If provided, this method will always be
420 	 * called when the flags change.
421 	 *
422 	 * @dev:	Chip to adjust
423 	 * @flags:	New flags value
424 	 * @return 0 if OK, -EINVAL if value is unsupported
425 	 */
426 	int (*set_flags)(struct udevice *dev, uint flags);
427 
428 	/**
429 	 * deblock() - recover a bus that is in an unknown state
430 	 *
431 	 * I2C is a synchronous protocol and resets of the processor in the
432 	 * middle of an access can block the I2C Bus until a powerdown of
433 	 * the full unit is done. This is because slaves can be stuck
434 	 * waiting for addition bus transitions for a transaction that will
435 	 * never complete. Resetting the I2C master does not help. The only
436 	 * way is to force the bus through a series of transitions to make
437 	 * sure that all slaves are done with the transaction. This method
438 	 * performs this 'deblocking' if support by the driver.
439 	 *
440 	 * This method is optional.
441 	 */
442 	int (*deblock)(struct udevice *bus);
443 };
444 
445 #define i2c_get_ops(dev)	((struct dm_i2c_ops *)(dev)->driver->ops)
446 
447 /**
448  * struct i2c_mux_ops - operations for an I2C mux
449  *
450  * The current mux state is expected to be stored in the mux itself since
451  * it is the only thing that knows how to make things work. The mux can
452  * record the current state and then avoid switching unless it is necessary.
453  * So select() can be skipped if the mux is already in the correct state.
454  * Also deselect() can be made a nop if required.
455  */
456 struct i2c_mux_ops {
457 	/**
458 	 * select() - select one of of I2C buses attached to a mux
459 	 *
460 	 * This will be called when there is no bus currently selected by the
461 	 * mux. This method does not need to deselect the old bus since
462 	 * deselect() will be already have been called if necessary.
463 	 *
464 	 * @mux:	Mux device
465 	 * @bus:	I2C bus to select
466 	 * @channel:	Channel number correponding to the bus to select
467 	 * @return 0 if OK, -ve on error
468 	 */
469 	int (*select)(struct udevice *mux, struct udevice *bus, uint channel);
470 
471 	/**
472 	 * deselect() - select one of of I2C buses attached to a mux
473 	 *
474 	 * This is used to deselect the currently selected I2C bus.
475 	 *
476 	 * @mux:	Mux device
477 	 * @bus:	I2C bus to deselect
478 	 * @channel:	Channel number correponding to the bus to deselect
479 	 * @return 0 if OK, -ve on error
480 	 */
481 	int (*deselect)(struct udevice *mux, struct udevice *bus, uint channel);
482 };
483 
484 #define i2c_mux_get_ops(dev)	((struct i2c_mux_ops *)(dev)->driver->ops)
485 
486 /**
487  * i2c_get_chip() - get a device to use to access a chip on a bus
488  *
489  * This returns the device for the given chip address. The device can then
490  * be used with calls to i2c_read(), i2c_write(), i2c_probe(), etc.
491  *
492  * @bus:	Bus to examine
493  * @chip_addr:	Chip address for the new device
494  * @offset_len:	Length of a register offset in bytes (normally 1)
495  * @devp:	Returns pointer to new device if found or -ENODEV if not
496  *		found
497  */
498 int i2c_get_chip(struct udevice *bus, uint chip_addr, uint offset_len,
499 		 struct udevice **devp);
500 
501 /**
502  * i2c_get_chip_for_busnum() - get a device to use to access a chip on
503  *			       a bus number
504  *
505  * This returns the device for the given chip address on a particular bus
506  * number.
507  *
508  * @busnum:	Bus number to examine
509  * @chip_addr:	Chip address for the new device
510  * @offset_len:	Length of a register offset in bytes (normally 1)
511  * @devp:	Returns pointer to new device if found or -ENODEV if not
512  *		found
513  */
514 int i2c_get_chip_for_busnum(int busnum, int chip_addr, uint offset_len,
515 			    struct udevice **devp);
516 
517 /**
518  * i2c_chip_ofdata_to_platdata() - Decode standard I2C platform data
519  *
520  * This decodes the chip address from a device tree node and puts it into
521  * its dm_i2c_chip structure. This should be called in your driver's
522  * ofdata_to_platdata() method.
523  *
524  * @blob:	Device tree blob
525  * @node:	Node offset to read from
526  * @spi:	Place to put the decoded information
527  */
528 int i2c_chip_ofdata_to_platdata(struct udevice *dev, struct dm_i2c_chip *chip);
529 
530 /**
531  * i2c_dump_msgs() - Dump a list of I2C messages
532  *
533  * This may be useful for debugging.
534  *
535  * @msg:	Message list to dump
536  * @nmsgs:	Number of messages
537  */
538 void i2c_dump_msgs(struct i2c_msg *msg, int nmsgs);
539 
540 #ifndef CONFIG_DM_I2C
541 
542 /*
543  * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
544  *
545  * The implementation MUST NOT use static or global variables if the
546  * I2C routines are used to read SDRAM configuration information
547  * because this is done before the memories are initialized. Limited
548  * use of stack-based variables are OK (the initial stack size is
549  * limited).
550  *
551  * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
552  */
553 
554 /*
555  * Configuration items.
556  */
557 #define I2C_RXTX_LEN	128	/* maximum tx/rx buffer length */
558 
559 #if !defined(CONFIG_SYS_I2C_MAX_HOPS)
560 /* no muxes used bus = i2c adapters */
561 #define CONFIG_SYS_I2C_DIRECT_BUS	1
562 #define CONFIG_SYS_I2C_MAX_HOPS		0
563 #define CONFIG_SYS_NUM_I2C_BUSES	ll_entry_count(struct i2c_adapter, i2c)
564 #else
565 /* we use i2c muxes */
566 #undef CONFIG_SYS_I2C_DIRECT_BUS
567 #endif
568 
569 /* define the I2C bus number for RTC and DTT if not already done */
570 #if !defined(CONFIG_SYS_RTC_BUS_NUM)
571 #define CONFIG_SYS_RTC_BUS_NUM		0
572 #endif
573 #if !defined(CONFIG_SYS_SPD_BUS_NUM)
574 #define CONFIG_SYS_SPD_BUS_NUM		0
575 #endif
576 
577 struct i2c_adapter {
578 	void		(*init)(struct i2c_adapter *adap, int speed,
579 				int slaveaddr);
580 	int		(*probe)(struct i2c_adapter *adap, uint8_t chip);
581 	int		(*read)(struct i2c_adapter *adap, uint8_t chip,
582 				uint addr, int alen, uint8_t *buffer,
583 				int len);
584 	int		(*write)(struct i2c_adapter *adap, uint8_t chip,
585 				uint addr, int alen, uint8_t *buffer,
586 				int len);
587 	uint		(*set_bus_speed)(struct i2c_adapter *adap,
588 				uint speed);
589 	int		speed;
590 	int		waitdelay;
591 	int		slaveaddr;
592 	int		init_done;
593 	int		hwadapnr;
594 	char		*name;
595 };
596 
597 #define U_BOOT_I2C_MKENT_COMPLETE(_init, _probe, _read, _write, \
598 		_set_speed, _speed, _slaveaddr, _hwadapnr, _name) \
599 	{ \
600 		.init		=	_init, \
601 		.probe		=	_probe, \
602 		.read		=	_read, \
603 		.write		=	_write, \
604 		.set_bus_speed	=	_set_speed, \
605 		.speed		=	_speed, \
606 		.slaveaddr	=	_slaveaddr, \
607 		.init_done	=	0, \
608 		.hwadapnr	=	_hwadapnr, \
609 		.name		=	#_name \
610 };
611 
612 #define U_BOOT_I2C_ADAP_COMPLETE(_name, _init, _probe, _read, _write, \
613 			_set_speed, _speed, _slaveaddr, _hwadapnr) \
614 	ll_entry_declare(struct i2c_adapter, _name, i2c) = \
615 	U_BOOT_I2C_MKENT_COMPLETE(_init, _probe, _read, _write, \
616 		 _set_speed, _speed, _slaveaddr, _hwadapnr, _name);
617 
618 struct i2c_adapter *i2c_get_adapter(int index);
619 
620 #ifndef CONFIG_SYS_I2C_DIRECT_BUS
621 struct i2c_mux {
622 	int	id;
623 	char	name[16];
624 };
625 
626 struct i2c_next_hop {
627 	struct i2c_mux		mux;
628 	uint8_t		chip;
629 	uint8_t		channel;
630 };
631 
632 struct i2c_bus_hose {
633 	int	adapter;
634 	struct i2c_next_hop	next_hop[CONFIG_SYS_I2C_MAX_HOPS];
635 };
636 #define I2C_NULL_HOP	{{-1, ""}, 0, 0}
637 extern struct i2c_bus_hose	i2c_bus[];
638 
639 #define I2C_ADAPTER(bus)	i2c_bus[bus].adapter
640 #else
641 #define I2C_ADAPTER(bus)	bus
642 #endif
643 #define	I2C_BUS			gd->cur_i2c_bus
644 
645 #define	I2C_ADAP_NR(bus)	i2c_get_adapter(I2C_ADAPTER(bus))
646 #define	I2C_ADAP		I2C_ADAP_NR(gd->cur_i2c_bus)
647 #define I2C_ADAP_HWNR		(I2C_ADAP->hwadapnr)
648 
649 #ifndef CONFIG_SYS_I2C_DIRECT_BUS
650 #define I2C_MUX_PCA9540_ID	1
651 #define I2C_MUX_PCA9540		{I2C_MUX_PCA9540_ID, "PCA9540B"}
652 #define I2C_MUX_PCA9542_ID	2
653 #define I2C_MUX_PCA9542		{I2C_MUX_PCA9542_ID, "PCA9542A"}
654 #define I2C_MUX_PCA9544_ID	3
655 #define I2C_MUX_PCA9544		{I2C_MUX_PCA9544_ID, "PCA9544A"}
656 #define I2C_MUX_PCA9547_ID	4
657 #define I2C_MUX_PCA9547		{I2C_MUX_PCA9547_ID, "PCA9547A"}
658 #define I2C_MUX_PCA9548_ID	5
659 #define I2C_MUX_PCA9548		{I2C_MUX_PCA9548_ID, "PCA9548"}
660 #endif
661 
662 #ifndef I2C_SOFT_DECLARATIONS
663 # if (defined(CONFIG_AT91RM9200) || \
664 	defined(CONFIG_AT91SAM9260) ||  defined(CONFIG_AT91SAM9261) || \
665 	defined(CONFIG_AT91SAM9263))
666 #  define I2C_SOFT_DECLARATIONS	at91_pio_t *pio	= (at91_pio_t *) ATMEL_BASE_PIOA;
667 # else
668 #  define I2C_SOFT_DECLARATIONS
669 # endif
670 #endif
671 
672 /*
673  * Many boards/controllers/drivers don't support an I2C slave interface so
674  * provide a default slave address for them for use in common code.  A real
675  * value for CONFIG_SYS_I2C_SLAVE should be defined for any board which does
676  * support a slave interface.
677  */
678 #ifndef	CONFIG_SYS_I2C_SLAVE
679 #define	CONFIG_SYS_I2C_SLAVE	0xfe
680 #endif
681 
682 /*
683  * Initialization, must be called once on start up, may be called
684  * repeatedly to change the speed and slave addresses.
685  */
686 #ifdef CONFIG_SYS_I2C_EARLY_INIT
687 void i2c_early_init_f(void);
688 #endif
689 void i2c_init(int speed, int slaveaddr);
690 void i2c_init_board(void);
691 
692 #ifdef CONFIG_SYS_I2C
693 /*
694  * i2c_get_bus_num:
695  *
696  *  Returns index of currently active I2C bus.  Zero-based.
697  */
698 unsigned int i2c_get_bus_num(void);
699 
700 /*
701  * i2c_set_bus_num:
702  *
703  *  Change the active I2C bus.  Subsequent read/write calls will
704  *  go to this one.
705  *
706  *	bus - bus index, zero based
707  *
708  *	Returns: 0 on success, not 0 on failure
709  *
710  */
711 int i2c_set_bus_num(unsigned int bus);
712 
713 /*
714  * i2c_init_all():
715  *
716  * Initializes all I2C adapters in the system. All i2c_adap structures must
717  * be initialized beforehead with function pointers and data, including
718  * speed and slaveaddr. Returns 0 on success, non-0 on failure.
719  */
720 void i2c_init_all(void);
721 
722 /*
723  * Probe the given I2C chip address.  Returns 0 if a chip responded,
724  * not 0 on failure.
725  */
726 int i2c_probe(uint8_t chip);
727 
728 /*
729  * Read/Write interface:
730  *   chip:    I2C chip address, range 0..127
731  *   addr:    Memory (register) address within the chip
732  *   alen:    Number of bytes to use for addr (typically 1, 2 for larger
733  *              memories, 0 for register type devices with only one
734  *              register)
735  *   buffer:  Where to read/write the data
736  *   len:     How many bytes to read/write
737  *
738  *   Returns: 0 on success, not 0 on failure
739  */
740 int i2c_read(uint8_t chip, unsigned int addr, int alen,
741 				uint8_t *buffer, int len);
742 
743 int i2c_write(uint8_t chip, unsigned int addr, int alen,
744 				uint8_t *buffer, int len);
745 
746 /*
747  * Utility routines to read/write registers.
748  */
749 uint8_t i2c_reg_read(uint8_t addr, uint8_t reg);
750 
751 void i2c_reg_write(uint8_t addr, uint8_t reg, uint8_t val);
752 
753 /*
754  * i2c_set_bus_speed:
755  *
756  *  Change the speed of the active I2C bus
757  *
758  *	speed - bus speed in Hz
759  *
760  *	Returns: new bus speed
761  *
762  */
763 unsigned int i2c_set_bus_speed(unsigned int speed);
764 
765 /*
766  * i2c_get_bus_speed:
767  *
768  *  Returns speed of currently active I2C bus in Hz
769  */
770 
771 unsigned int i2c_get_bus_speed(void);
772 
773 #else
774 
775 /*
776  * Probe the given I2C chip address.  Returns 0 if a chip responded,
777  * not 0 on failure.
778  */
779 int i2c_probe(uchar chip);
780 
781 /*
782  * Read/Write interface:
783  *   chip:    I2C chip address, range 0..127
784  *   addr:    Memory (register) address within the chip
785  *   alen:    Number of bytes to use for addr (typically 1, 2 for larger
786  *              memories, 0 for register type devices with only one
787  *              register)
788  *   buffer:  Where to read/write the data
789  *   len:     How many bytes to read/write
790  *
791  *   Returns: 0 on success, not 0 on failure
792  */
793 int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len);
794 int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len);
795 
796 /*
797  * Utility routines to read/write registers.
798  */
799 static inline u8 i2c_reg_read(u8 addr, u8 reg)
800 {
801 	u8 buf;
802 
803 #ifdef DEBUG
804 	printf("%s: addr=0x%02x, reg=0x%02x\n", __func__, addr, reg);
805 #endif
806 
807 	i2c_read(addr, reg, 1, &buf, 1);
808 
809 	return buf;
810 }
811 
812 static inline void i2c_reg_write(u8 addr, u8 reg, u8 val)
813 {
814 #ifdef DEBUG
815 	printf("%s: addr=0x%02x, reg=0x%02x, val=0x%02x\n",
816 	       __func__, addr, reg, val);
817 #endif
818 
819 	i2c_write(addr, reg, 1, &val, 1);
820 }
821 
822 /*
823  * Functions for setting the current I2C bus and its speed
824  */
825 
826 /*
827  * i2c_set_bus_num:
828  *
829  *  Change the active I2C bus.  Subsequent read/write calls will
830  *  go to this one.
831  *
832  *	bus - bus index, zero based
833  *
834  *	Returns: 0 on success, not 0 on failure
835  *
836  */
837 int i2c_set_bus_num(unsigned int bus);
838 
839 /*
840  * i2c_get_bus_num:
841  *
842  *  Returns index of currently active I2C bus.  Zero-based.
843  */
844 
845 unsigned int i2c_get_bus_num(void);
846 
847 /*
848  * i2c_set_bus_speed:
849  *
850  *  Change the speed of the active I2C bus
851  *
852  *	speed - bus speed in Hz
853  *
854  *	Returns: 0 on success, not 0 on failure
855  *
856  */
857 int i2c_set_bus_speed(unsigned int);
858 
859 /*
860  * i2c_get_bus_speed:
861  *
862  *  Returns speed of currently active I2C bus in Hz
863  */
864 
865 unsigned int i2c_get_bus_speed(void);
866 #endif /* CONFIG_SYS_I2C */
867 
868 /*
869  * only for backwardcompatibility, should go away if we switched
870  * completely to new multibus support.
871  */
872 #if defined(CONFIG_SYS_I2C) || defined(CONFIG_I2C_MULTI_BUS)
873 # if !defined(CONFIG_SYS_MAX_I2C_BUS)
874 #  define CONFIG_SYS_MAX_I2C_BUS		2
875 # endif
876 # define I2C_MULTI_BUS				1
877 #else
878 # define CONFIG_SYS_MAX_I2C_BUS		1
879 # define I2C_MULTI_BUS				0
880 #endif
881 
882 /* NOTE: These two functions MUST be always_inline to avoid code growth! */
883 static inline unsigned int I2C_GET_BUS(void) __attribute__((always_inline));
884 static inline unsigned int I2C_GET_BUS(void)
885 {
886 	return I2C_MULTI_BUS ? i2c_get_bus_num() : 0;
887 }
888 
889 static inline void I2C_SET_BUS(unsigned int bus) __attribute__((always_inline));
890 static inline void I2C_SET_BUS(unsigned int bus)
891 {
892 	if (I2C_MULTI_BUS)
893 		i2c_set_bus_num(bus);
894 }
895 
896 /* Multi I2C definitions */
897 enum {
898 	I2C_0, I2C_1, I2C_2, I2C_3, I2C_4, I2C_5, I2C_6, I2C_7,
899 	I2C_8, I2C_9, I2C_10,
900 };
901 
902 /**
903  * Get FDT values for i2c bus.
904  *
905  * @param blob  Device tree blbo
906  * @return the number of I2C bus
907  */
908 void board_i2c_init(const void *blob);
909 
910 /**
911  * Find the I2C bus number by given a FDT I2C node.
912  *
913  * @param blob  Device tree blbo
914  * @param node  FDT I2C node to find
915  * @return the number of I2C bus (zero based), or -1 on error
916  */
917 int i2c_get_bus_num_fdt(int node);
918 
919 /**
920  * Reset the I2C bus represented by the given a FDT I2C node.
921  *
922  * @param blob  Device tree blbo
923  * @param node  FDT I2C node to find
924  * @return 0 if port was reset, -1 if not found
925  */
926 int i2c_reset_port_fdt(const void *blob, int node);
927 
928 #endif /* !CONFIG_DM_I2C */
929 
930 #endif	/* _I2C_H_ */
931