xref: /openbmc/u-boot/include/i2c.h (revision 5271dcf5)
1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3  * Copyright (C) 2009 Sergey Kubushyn <ksi@koi8.net>
4  * Copyright (C) 2009 - 2013 Heiko Schocher <hs@denx.de>
5  * Changes for multibus/multiadapter I2C support.
6  *
7  * (C) Copyright 2001
8  * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com.
9  *
10  * The original I2C interface was
11  *   (C) 2000 by Paolo Scaffardi (arsenio@tin.it)
12  *   AIRVENT SAM s.p.a - RIMINI(ITALY)
13  * but has been changed substantially.
14  */
15 
16 #ifndef _I2C_H_
17 #define _I2C_H_
18 
19 /*
20  * For now there are essentially two parts to this file - driver model
21  * here at the top, and the older code below (with CONFIG_SYS_I2C being
22  * most recent). The plan is to migrate everything to driver model.
23  * The driver model structures and API are separate as they are different
24  * enough as to be incompatible for compilation purposes.
25  */
26 
27 enum dm_i2c_chip_flags {
28 	DM_I2C_CHIP_10BIT	= 1 << 0, /* Use 10-bit addressing */
29 	DM_I2C_CHIP_RD_ADDRESS	= 1 << 1, /* Send address for each read byte */
30 	DM_I2C_CHIP_WR_ADDRESS	= 1 << 2, /* Send address for each write byte */
31 };
32 
33 struct udevice;
34 /**
35  * struct dm_i2c_chip - information about an i2c chip
36  *
37  * An I2C chip is a device on the I2C bus. It sits at a particular address
38  * and normally supports 7-bit or 10-bit addressing.
39  *
40  * To obtain this structure, use dev_get_parent_platdata(dev) where dev is
41  * the chip to examine.
42  *
43  * @chip_addr:	Chip address on bus
44  * @offset_len: Length of offset in bytes. A single byte offset can
45  *		represent up to 256 bytes. A value larger than 1 may be
46  *		needed for larger devices.
47  * @flags:	Flags for this chip (dm_i2c_chip_flags)
48  * @emul: Emulator for this chip address (only used for emulation)
49  */
50 struct dm_i2c_chip {
51 	uint chip_addr;
52 	uint offset_len;
53 	uint flags;
54 #ifdef CONFIG_SANDBOX
55 	struct udevice *emul;
56 	bool test_mode;
57 #endif
58 };
59 
60 /**
61  * struct dm_i2c_bus- information about an i2c bus
62  *
63  * An I2C bus contains 0 or more chips on it, each at its own address. The
64  * bus can operate at different speeds (measured in Hz, typically 100KHz
65  * or 400KHz).
66  *
67  * To obtain this structure, use dev_get_uclass_priv(bus) where bus is the
68  * I2C bus udevice.
69  *
70  * @speed_hz: Bus speed in hertz (typically 100000)
71  */
72 struct dm_i2c_bus {
73 	int speed_hz;
74 };
75 
76 /*
77  * Not all of these flags are implemented in the U-Boot API
78  */
79 enum dm_i2c_msg_flags {
80 	I2C_M_TEN		= 0x0010, /* ten-bit chip address */
81 	I2C_M_RD		= 0x0001, /* read data, from slave to master */
82 	I2C_M_STOP		= 0x8000, /* send stop after this message */
83 	I2C_M_NOSTART		= 0x4000, /* no start before this message */
84 	I2C_M_REV_DIR_ADDR	= 0x2000, /* invert polarity of R/W bit */
85 	I2C_M_IGNORE_NAK	= 0x1000, /* continue after NAK */
86 	I2C_M_NO_RD_ACK		= 0x0800, /* skip the Ack bit on reads */
87 	I2C_M_RECV_LEN		= 0x0400, /* length is first received byte */
88 };
89 
90 /**
91  * struct i2c_msg - an I2C message
92  *
93  * @addr:	Slave address
94  * @flags:	Flags (see enum dm_i2c_msg_flags)
95  * @len:	Length of buffer in bytes, may be 0 for a probe
96  * @buf:	Buffer to send/receive, or NULL if no data
97  */
98 struct i2c_msg {
99 	uint addr;
100 	uint flags;
101 	uint len;
102 	u8 *buf;
103 };
104 
105 /**
106  * struct i2c_msg_list - a list of I2C messages
107  *
108  * This is called i2c_rdwr_ioctl_data in Linux but the name does not seem
109  * appropriate in U-Boot.
110  *
111  * @msg:	Pointer to i2c_msg array
112  * @nmsgs:	Number of elements in the array
113  */
114 struct i2c_msg_list {
115 	struct i2c_msg *msgs;
116 	uint nmsgs;
117 };
118 
119 /**
120  * dm_i2c_read() - read bytes from an I2C chip
121  *
122  * To obtain an I2C device (called a 'chip') given the I2C bus address you
123  * can use i2c_get_chip(). To obtain a bus by bus number use
124  * uclass_get_device_by_seq(UCLASS_I2C, <bus number>).
125  *
126  * To set the address length of a devce use i2c_set_addr_len(). It
127  * defaults to 1.
128  *
129  * @dev:	Chip to read from
130  * @offset:	Offset within chip to start reading
131  * @buffer:	Place to put data
132  * @len:	Number of bytes to read
133  *
134  * @return 0 on success, -ve on failure
135  */
136 int dm_i2c_read(struct udevice *dev, uint offset, uint8_t *buffer, int len);
137 
138 /**
139  * dm_i2c_write() - write bytes to an I2C chip
140  *
141  * See notes for dm_i2c_read() above.
142  *
143  * @dev:	Chip to write to
144  * @offset:	Offset within chip to start writing
145  * @buffer:	Buffer containing data to write
146  * @len:	Number of bytes to write
147  *
148  * @return 0 on success, -ve on failure
149  */
150 int dm_i2c_write(struct udevice *dev, uint offset, const uint8_t *buffer,
151 		 int len);
152 
153 /**
154  * dm_i2c_probe() - probe a particular chip address
155  *
156  * This can be useful to check for the existence of a chip on the bus.
157  * It is typically implemented by writing the chip address to the bus
158  * and checking that the chip replies with an ACK.
159  *
160  * @bus:	Bus to probe
161  * @chip_addr:	7-bit address to probe (10-bit and others are not supported)
162  * @chip_flags:	Flags for the probe (see enum dm_i2c_chip_flags)
163  * @devp:	Returns the device found, or NULL if none
164  * @return 0 if a chip was found at that address, -ve if not
165  */
166 int dm_i2c_probe(struct udevice *bus, uint chip_addr, uint chip_flags,
167 		 struct udevice **devp);
168 
169 /**
170  * dm_i2c_reg_read() - Read a value from an I2C register
171  *
172  * This reads a single value from the given address in an I2C chip
173  *
174  * @dev:	Device to use for transfer
175  * @addr:	Address to read from
176  * @return value read, or -ve on error
177  */
178 int dm_i2c_reg_read(struct udevice *dev, uint offset);
179 
180 /**
181  * dm_i2c_reg_write() - Write a value to an I2C register
182  *
183  * This writes a single value to the given address in an I2C chip
184  *
185  * @dev:	Device to use for transfer
186  * @addr:	Address to write to
187  * @val:	Value to write (normally a byte)
188  * @return 0 on success, -ve on error
189  */
190 int dm_i2c_reg_write(struct udevice *dev, uint offset, unsigned int val);
191 
192 /**
193  * dm_i2c_xfer() - Transfer messages over I2C
194  *
195  * This transfers a raw message. It is best to use dm_i2c_reg_read/write()
196  * instead.
197  *
198  * @dev:	Device to use for transfer
199  * @msg:	List of messages to transfer
200  * @nmsgs:	Number of messages to transfer
201  * @return 0 on success, -ve on error
202  */
203 int dm_i2c_xfer(struct udevice *dev, struct i2c_msg *msg, int nmsgs);
204 
205 /**
206  * dm_i2c_set_bus_speed() - set the speed of a bus
207  *
208  * @bus:	Bus to adjust
209  * @speed:	Requested speed in Hz
210  * @return 0 if OK, -EINVAL for invalid values
211  */
212 int dm_i2c_set_bus_speed(struct udevice *bus, unsigned int speed);
213 
214 /**
215  * dm_i2c_get_bus_speed() - get the speed of a bus
216  *
217  * @bus:	Bus to check
218  * @return speed of selected I2C bus in Hz, -ve on error
219  */
220 int dm_i2c_get_bus_speed(struct udevice *bus);
221 
222 /**
223  * i2c_set_chip_flags() - set flags for a chip
224  *
225  * Typically addresses are 7 bits, but for 10-bit addresses you should set
226  * flags to DM_I2C_CHIP_10BIT. All accesses will then use 10-bit addressing.
227  *
228  * @dev:	Chip to adjust
229  * @flags:	New flags
230  * @return 0 if OK, -EINVAL if value is unsupported, other -ve value on error
231  */
232 int i2c_set_chip_flags(struct udevice *dev, uint flags);
233 
234 /**
235  * i2c_get_chip_flags() - get flags for a chip
236  *
237  * @dev:	Chip to check
238  * @flagsp:	Place to put flags
239  * @return 0 if OK, other -ve value on error
240  */
241 int i2c_get_chip_flags(struct udevice *dev, uint *flagsp);
242 
243 /**
244  * i2c_set_offset_len() - set the offset length for a chip
245  *
246  * The offset used to access a chip may be up to 4 bytes long. Typically it
247  * is only 1 byte, which is enough for chips with 256 bytes of memory or
248  * registers. The default value is 1, but you can call this function to
249  * change it.
250  *
251  * @offset_len:	New offset length value (typically 1 or 2)
252  */
253 int i2c_set_chip_offset_len(struct udevice *dev, uint offset_len);
254 
255 /**
256  * i2c_get_offset_len() - get the offset length for a chip
257  *
258  * @return:	Current offset length value (typically 1 or 2)
259  */
260 int i2c_get_chip_offset_len(struct udevice *dev);
261 
262 /**
263  * i2c_deblock() - recover a bus that is in an unknown state
264  *
265  * See the deblock() method in 'struct dm_i2c_ops' for full information
266  *
267  * @bus:	Bus to recover
268  * @return 0 if OK, -ve on error
269  */
270 int i2c_deblock(struct udevice *bus);
271 
272 #ifdef CONFIG_DM_I2C_COMPAT
273 /**
274  * i2c_probe() - Compatibility function for driver model
275  *
276  * Calls dm_i2c_probe() on the current bus
277  */
278 int i2c_probe(uint8_t chip_addr);
279 
280 /**
281  * i2c_read() - Compatibility function for driver model
282  *
283  * Calls dm_i2c_read() with the device corresponding to @chip_addr, and offset
284  * set to @addr. @alen must match the current setting for the device.
285  */
286 int i2c_read(uint8_t chip_addr, unsigned int addr, int alen, uint8_t *buffer,
287 	     int len);
288 
289 /**
290  * i2c_write() - Compatibility function for driver model
291  *
292  * Calls dm_i2c_write() with the device corresponding to @chip_addr, and offset
293  * set to @addr. @alen must match the current setting for the device.
294  */
295 int i2c_write(uint8_t chip_addr, unsigned int addr, int alen, uint8_t *buffer,
296 	      int len);
297 
298 /**
299  * i2c_get_bus_num_fdt() - Compatibility function for driver model
300  *
301  * @return the bus number associated with the given device tree node
302  */
303 int i2c_get_bus_num_fdt(int node);
304 
305 /**
306  * i2c_get_bus_num() - Compatibility function for driver model
307  *
308  * @return the 'current' bus number
309  */
310 unsigned int i2c_get_bus_num(void);
311 
312 /**
313  * i2c_set_bus_num() - Compatibility function for driver model
314  *
315  * Sets the 'current' bus
316  */
317 int i2c_set_bus_num(unsigned int bus);
318 
319 static inline void I2C_SET_BUS(unsigned int bus)
320 {
321 	i2c_set_bus_num(bus);
322 }
323 
324 static inline unsigned int I2C_GET_BUS(void)
325 {
326 	return i2c_get_bus_num();
327 }
328 
329 /**
330  * i2c_init() - Compatibility function for driver model
331  *
332  * This function does nothing.
333  */
334 void i2c_init(int speed, int slaveaddr);
335 
336 /**
337  * board_i2c_init() - Compatibility function for driver model
338  *
339  * @param blob  Device tree blbo
340  * @return the number of I2C bus
341  */
342 void board_i2c_init(const void *blob);
343 
344 /*
345  * Compatibility functions for driver model.
346  */
347 uint8_t i2c_reg_read(uint8_t addr, uint8_t reg);
348 void i2c_reg_write(uint8_t addr, uint8_t reg, uint8_t val);
349 
350 #endif
351 
352 /**
353  * struct dm_i2c_ops - driver operations for I2C uclass
354  *
355  * Drivers should support these operations unless otherwise noted. These
356  * operations are intended to be used by uclass code, not directly from
357  * other code.
358  */
359 struct dm_i2c_ops {
360 	/**
361 	 * xfer() - transfer a list of I2C messages
362 	 *
363 	 * @bus:	Bus to read from
364 	 * @msg:	List of messages to transfer
365 	 * @nmsgs:	Number of messages in the list
366 	 * @return 0 if OK, -EREMOTEIO if the slave did not ACK a byte,
367 	 *	-ECOMM if the speed cannot be supported, -EPROTO if the chip
368 	 *	flags cannot be supported, other -ve value on some other error
369 	 */
370 	int (*xfer)(struct udevice *bus, struct i2c_msg *msg, int nmsgs);
371 
372 	/**
373 	 * probe_chip() - probe for the presense of a chip address
374 	 *
375 	 * This function is optional. If omitted, the uclass will send a zero
376 	 * length message instead.
377 	 *
378 	 * @bus:	Bus to probe
379 	 * @chip_addr:	Chip address to probe
380 	 * @chip_flags:	Probe flags (enum dm_i2c_chip_flags)
381 	 * @return 0 if chip was found, -EREMOTEIO if not, -ENOSYS to fall back
382 	 * to default probem other -ve value on error
383 	 */
384 	int (*probe_chip)(struct udevice *bus, uint chip_addr, uint chip_flags);
385 
386 	/**
387 	 * set_bus_speed() - set the speed of a bus (optional)
388 	 *
389 	 * The bus speed value will be updated by the uclass if this function
390 	 * does not return an error. This method is optional - if it is not
391 	 * provided then the driver can read the speed from
392 	 * dev_get_uclass_priv(bus)->speed_hz
393 	 *
394 	 * @bus:	Bus to adjust
395 	 * @speed:	Requested speed in Hz
396 	 * @return 0 if OK, -EINVAL for invalid values
397 	 */
398 	int (*set_bus_speed)(struct udevice *bus, unsigned int speed);
399 
400 	/**
401 	 * get_bus_speed() - get the speed of a bus (optional)
402 	 *
403 	 * Normally this can be provided by the uclass, but if you want your
404 	 * driver to check the bus speed by looking at the hardware, you can
405 	 * implement that here. This method is optional. This method would
406 	 * normally be expected to return dev_get_uclass_priv(bus)->speed_hz.
407 	 *
408 	 * @bus:	Bus to check
409 	 * @return speed of selected I2C bus in Hz, -ve on error
410 	 */
411 	int (*get_bus_speed)(struct udevice *bus);
412 
413 	/**
414 	 * set_flags() - set the flags for a chip (optional)
415 	 *
416 	 * This is generally implemented by the uclass, but drivers can
417 	 * check the value to ensure that unsupported options are not used.
418 	 * This method is optional. If provided, this method will always be
419 	 * called when the flags change.
420 	 *
421 	 * @dev:	Chip to adjust
422 	 * @flags:	New flags value
423 	 * @return 0 if OK, -EINVAL if value is unsupported
424 	 */
425 	int (*set_flags)(struct udevice *dev, uint flags);
426 
427 	/**
428 	 * deblock() - recover a bus that is in an unknown state
429 	 *
430 	 * I2C is a synchronous protocol and resets of the processor in the
431 	 * middle of an access can block the I2C Bus until a powerdown of
432 	 * the full unit is done. This is because slaves can be stuck
433 	 * waiting for addition bus transitions for a transaction that will
434 	 * never complete. Resetting the I2C master does not help. The only
435 	 * way is to force the bus through a series of transitions to make
436 	 * sure that all slaves are done with the transaction. This method
437 	 * performs this 'deblocking' if support by the driver.
438 	 *
439 	 * This method is optional.
440 	 */
441 	int (*deblock)(struct udevice *bus);
442 };
443 
444 #define i2c_get_ops(dev)	((struct dm_i2c_ops *)(dev)->driver->ops)
445 
446 /**
447  * struct i2c_mux_ops - operations for an I2C mux
448  *
449  * The current mux state is expected to be stored in the mux itself since
450  * it is the only thing that knows how to make things work. The mux can
451  * record the current state and then avoid switching unless it is necessary.
452  * So select() can be skipped if the mux is already in the correct state.
453  * Also deselect() can be made a nop if required.
454  */
455 struct i2c_mux_ops {
456 	/**
457 	 * select() - select one of of I2C buses attached to a mux
458 	 *
459 	 * This will be called when there is no bus currently selected by the
460 	 * mux. This method does not need to deselect the old bus since
461 	 * deselect() will be already have been called if necessary.
462 	 *
463 	 * @mux:	Mux device
464 	 * @bus:	I2C bus to select
465 	 * @channel:	Channel number correponding to the bus to select
466 	 * @return 0 if OK, -ve on error
467 	 */
468 	int (*select)(struct udevice *mux, struct udevice *bus, uint channel);
469 
470 	/**
471 	 * deselect() - select one of of I2C buses attached to a mux
472 	 *
473 	 * This is used to deselect the currently selected I2C bus.
474 	 *
475 	 * @mux:	Mux device
476 	 * @bus:	I2C bus to deselect
477 	 * @channel:	Channel number correponding to the bus to deselect
478 	 * @return 0 if OK, -ve on error
479 	 */
480 	int (*deselect)(struct udevice *mux, struct udevice *bus, uint channel);
481 };
482 
483 #define i2c_mux_get_ops(dev)	((struct i2c_mux_ops *)(dev)->driver->ops)
484 
485 /**
486  * i2c_get_chip() - get a device to use to access a chip on a bus
487  *
488  * This returns the device for the given chip address. The device can then
489  * be used with calls to i2c_read(), i2c_write(), i2c_probe(), etc.
490  *
491  * @bus:	Bus to examine
492  * @chip_addr:	Chip address for the new device
493  * @offset_len:	Length of a register offset in bytes (normally 1)
494  * @devp:	Returns pointer to new device if found or -ENODEV if not
495  *		found
496  */
497 int i2c_get_chip(struct udevice *bus, uint chip_addr, uint offset_len,
498 		 struct udevice **devp);
499 
500 /**
501  * i2c_get_chip_for_busnum() - get a device to use to access a chip on
502  *			       a bus number
503  *
504  * This returns the device for the given chip address on a particular bus
505  * number.
506  *
507  * @busnum:	Bus number to examine
508  * @chip_addr:	Chip address for the new device
509  * @offset_len:	Length of a register offset in bytes (normally 1)
510  * @devp:	Returns pointer to new device if found or -ENODEV if not
511  *		found
512  */
513 int i2c_get_chip_for_busnum(int busnum, int chip_addr, uint offset_len,
514 			    struct udevice **devp);
515 
516 /**
517  * i2c_chip_ofdata_to_platdata() - Decode standard I2C platform data
518  *
519  * This decodes the chip address from a device tree node and puts it into
520  * its dm_i2c_chip structure. This should be called in your driver's
521  * ofdata_to_platdata() method.
522  *
523  * @blob:	Device tree blob
524  * @node:	Node offset to read from
525  * @spi:	Place to put the decoded information
526  */
527 int i2c_chip_ofdata_to_platdata(struct udevice *dev, struct dm_i2c_chip *chip);
528 
529 /**
530  * i2c_dump_msgs() - Dump a list of I2C messages
531  *
532  * This may be useful for debugging.
533  *
534  * @msg:	Message list to dump
535  * @nmsgs:	Number of messages
536  */
537 void i2c_dump_msgs(struct i2c_msg *msg, int nmsgs);
538 
539 /**
540  * i2c_emul_find() - Find an emulator for an i2c sandbox device
541  *
542  * This looks at the device's 'emul' phandle
543  *
544  * @dev: Device to find an emulator for
545  * @emulp: Returns the associated emulator, if found *
546  * @return 0 if OK, -ENOENT or -ENODEV if not found
547  */
548 int i2c_emul_find(struct udevice *dev, struct udevice **emulp);
549 
550 /**
551  * i2c_emul_get_device() - Find the device being emulated
552  *
553  * Given an emulator this returns the associated device
554  *
555  * @emul: Emulator for the device
556  * @return device that @emul is emulating
557  */
558 struct udevice *i2c_emul_get_device(struct udevice *emul);
559 
560 #ifndef CONFIG_DM_I2C
561 
562 /*
563  * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
564  *
565  * The implementation MUST NOT use static or global variables if the
566  * I2C routines are used to read SDRAM configuration information
567  * because this is done before the memories are initialized. Limited
568  * use of stack-based variables are OK (the initial stack size is
569  * limited).
570  *
571  * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
572  */
573 
574 /*
575  * Configuration items.
576  */
577 #define I2C_RXTX_LEN	128	/* maximum tx/rx buffer length */
578 
579 #if !defined(CONFIG_SYS_I2C_MAX_HOPS)
580 /* no muxes used bus = i2c adapters */
581 #define CONFIG_SYS_I2C_DIRECT_BUS	1
582 #define CONFIG_SYS_I2C_MAX_HOPS		0
583 #define CONFIG_SYS_NUM_I2C_BUSES	ll_entry_count(struct i2c_adapter, i2c)
584 #else
585 /* we use i2c muxes */
586 #undef CONFIG_SYS_I2C_DIRECT_BUS
587 #endif
588 
589 /* define the I2C bus number for RTC and DTT if not already done */
590 #if !defined(CONFIG_SYS_RTC_BUS_NUM)
591 #define CONFIG_SYS_RTC_BUS_NUM		0
592 #endif
593 #if !defined(CONFIG_SYS_SPD_BUS_NUM)
594 #define CONFIG_SYS_SPD_BUS_NUM		0
595 #endif
596 
597 struct i2c_adapter {
598 	void		(*init)(struct i2c_adapter *adap, int speed,
599 				int slaveaddr);
600 	int		(*probe)(struct i2c_adapter *adap, uint8_t chip);
601 	int		(*read)(struct i2c_adapter *adap, uint8_t chip,
602 				uint addr, int alen, uint8_t *buffer,
603 				int len);
604 	int		(*write)(struct i2c_adapter *adap, uint8_t chip,
605 				uint addr, int alen, uint8_t *buffer,
606 				int len);
607 	uint		(*set_bus_speed)(struct i2c_adapter *adap,
608 				uint speed);
609 	int		speed;
610 	int		waitdelay;
611 	int		slaveaddr;
612 	int		init_done;
613 	int		hwadapnr;
614 	char		*name;
615 };
616 
617 #define U_BOOT_I2C_MKENT_COMPLETE(_init, _probe, _read, _write, \
618 		_set_speed, _speed, _slaveaddr, _hwadapnr, _name) \
619 	{ \
620 		.init		=	_init, \
621 		.probe		=	_probe, \
622 		.read		=	_read, \
623 		.write		=	_write, \
624 		.set_bus_speed	=	_set_speed, \
625 		.speed		=	_speed, \
626 		.slaveaddr	=	_slaveaddr, \
627 		.init_done	=	0, \
628 		.hwadapnr	=	_hwadapnr, \
629 		.name		=	#_name \
630 };
631 
632 #define U_BOOT_I2C_ADAP_COMPLETE(_name, _init, _probe, _read, _write, \
633 			_set_speed, _speed, _slaveaddr, _hwadapnr) \
634 	ll_entry_declare(struct i2c_adapter, _name, i2c) = \
635 	U_BOOT_I2C_MKENT_COMPLETE(_init, _probe, _read, _write, \
636 		 _set_speed, _speed, _slaveaddr, _hwadapnr, _name);
637 
638 struct i2c_adapter *i2c_get_adapter(int index);
639 
640 #ifndef CONFIG_SYS_I2C_DIRECT_BUS
641 struct i2c_mux {
642 	int	id;
643 	char	name[16];
644 };
645 
646 struct i2c_next_hop {
647 	struct i2c_mux		mux;
648 	uint8_t		chip;
649 	uint8_t		channel;
650 };
651 
652 struct i2c_bus_hose {
653 	int	adapter;
654 	struct i2c_next_hop	next_hop[CONFIG_SYS_I2C_MAX_HOPS];
655 };
656 #define I2C_NULL_HOP	{{-1, ""}, 0, 0}
657 extern struct i2c_bus_hose	i2c_bus[];
658 
659 #define I2C_ADAPTER(bus)	i2c_bus[bus].adapter
660 #else
661 #define I2C_ADAPTER(bus)	bus
662 #endif
663 #define	I2C_BUS			gd->cur_i2c_bus
664 
665 #define	I2C_ADAP_NR(bus)	i2c_get_adapter(I2C_ADAPTER(bus))
666 #define	I2C_ADAP		I2C_ADAP_NR(gd->cur_i2c_bus)
667 #define I2C_ADAP_HWNR		(I2C_ADAP->hwadapnr)
668 
669 #ifndef CONFIG_SYS_I2C_DIRECT_BUS
670 #define I2C_MUX_PCA9540_ID	1
671 #define I2C_MUX_PCA9540		{I2C_MUX_PCA9540_ID, "PCA9540B"}
672 #define I2C_MUX_PCA9542_ID	2
673 #define I2C_MUX_PCA9542		{I2C_MUX_PCA9542_ID, "PCA9542A"}
674 #define I2C_MUX_PCA9544_ID	3
675 #define I2C_MUX_PCA9544		{I2C_MUX_PCA9544_ID, "PCA9544A"}
676 #define I2C_MUX_PCA9547_ID	4
677 #define I2C_MUX_PCA9547		{I2C_MUX_PCA9547_ID, "PCA9547A"}
678 #define I2C_MUX_PCA9548_ID	5
679 #define I2C_MUX_PCA9548		{I2C_MUX_PCA9548_ID, "PCA9548"}
680 #endif
681 
682 #ifndef I2C_SOFT_DECLARATIONS
683 # if (defined(CONFIG_AT91RM9200) || \
684 	defined(CONFIG_AT91SAM9260) ||  defined(CONFIG_AT91SAM9261) || \
685 	defined(CONFIG_AT91SAM9263))
686 #  define I2C_SOFT_DECLARATIONS	at91_pio_t *pio	= (at91_pio_t *) ATMEL_BASE_PIOA;
687 # else
688 #  define I2C_SOFT_DECLARATIONS
689 # endif
690 #endif
691 
692 /*
693  * Many boards/controllers/drivers don't support an I2C slave interface so
694  * provide a default slave address for them for use in common code.  A real
695  * value for CONFIG_SYS_I2C_SLAVE should be defined for any board which does
696  * support a slave interface.
697  */
698 #ifndef	CONFIG_SYS_I2C_SLAVE
699 #define	CONFIG_SYS_I2C_SLAVE	0xfe
700 #endif
701 
702 /*
703  * Initialization, must be called once on start up, may be called
704  * repeatedly to change the speed and slave addresses.
705  */
706 #ifdef CONFIG_SYS_I2C_EARLY_INIT
707 void i2c_early_init_f(void);
708 #endif
709 void i2c_init(int speed, int slaveaddr);
710 void i2c_init_board(void);
711 
712 #ifdef CONFIG_SYS_I2C
713 /*
714  * i2c_get_bus_num:
715  *
716  *  Returns index of currently active I2C bus.  Zero-based.
717  */
718 unsigned int i2c_get_bus_num(void);
719 
720 /*
721  * i2c_set_bus_num:
722  *
723  *  Change the active I2C bus.  Subsequent read/write calls will
724  *  go to this one.
725  *
726  *	bus - bus index, zero based
727  *
728  *	Returns: 0 on success, not 0 on failure
729  *
730  */
731 int i2c_set_bus_num(unsigned int bus);
732 
733 /*
734  * i2c_init_all():
735  *
736  * Initializes all I2C adapters in the system. All i2c_adap structures must
737  * be initialized beforehead with function pointers and data, including
738  * speed and slaveaddr. Returns 0 on success, non-0 on failure.
739  */
740 void i2c_init_all(void);
741 
742 /*
743  * Probe the given I2C chip address.  Returns 0 if a chip responded,
744  * not 0 on failure.
745  */
746 int i2c_probe(uint8_t chip);
747 
748 /*
749  * Read/Write interface:
750  *   chip:    I2C chip address, range 0..127
751  *   addr:    Memory (register) address within the chip
752  *   alen:    Number of bytes to use for addr (typically 1, 2 for larger
753  *              memories, 0 for register type devices with only one
754  *              register)
755  *   buffer:  Where to read/write the data
756  *   len:     How many bytes to read/write
757  *
758  *   Returns: 0 on success, not 0 on failure
759  */
760 int i2c_read(uint8_t chip, unsigned int addr, int alen,
761 				uint8_t *buffer, int len);
762 
763 int i2c_write(uint8_t chip, unsigned int addr, int alen,
764 				uint8_t *buffer, int len);
765 
766 /*
767  * Utility routines to read/write registers.
768  */
769 uint8_t i2c_reg_read(uint8_t addr, uint8_t reg);
770 
771 void i2c_reg_write(uint8_t addr, uint8_t reg, uint8_t val);
772 
773 /*
774  * i2c_set_bus_speed:
775  *
776  *  Change the speed of the active I2C bus
777  *
778  *	speed - bus speed in Hz
779  *
780  *	Returns: new bus speed
781  *
782  */
783 unsigned int i2c_set_bus_speed(unsigned int speed);
784 
785 /*
786  * i2c_get_bus_speed:
787  *
788  *  Returns speed of currently active I2C bus in Hz
789  */
790 
791 unsigned int i2c_get_bus_speed(void);
792 
793 #else
794 
795 /*
796  * Probe the given I2C chip address.  Returns 0 if a chip responded,
797  * not 0 on failure.
798  */
799 int i2c_probe(uchar chip);
800 
801 /*
802  * Read/Write interface:
803  *   chip:    I2C chip address, range 0..127
804  *   addr:    Memory (register) address within the chip
805  *   alen:    Number of bytes to use for addr (typically 1, 2 for larger
806  *              memories, 0 for register type devices with only one
807  *              register)
808  *   buffer:  Where to read/write the data
809  *   len:     How many bytes to read/write
810  *
811  *   Returns: 0 on success, not 0 on failure
812  */
813 int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len);
814 int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len);
815 
816 /*
817  * Utility routines to read/write registers.
818  */
819 static inline u8 i2c_reg_read(u8 addr, u8 reg)
820 {
821 	u8 buf;
822 
823 #ifdef DEBUG
824 	printf("%s: addr=0x%02x, reg=0x%02x\n", __func__, addr, reg);
825 #endif
826 
827 	i2c_read(addr, reg, 1, &buf, 1);
828 
829 	return buf;
830 }
831 
832 static inline void i2c_reg_write(u8 addr, u8 reg, u8 val)
833 {
834 #ifdef DEBUG
835 	printf("%s: addr=0x%02x, reg=0x%02x, val=0x%02x\n",
836 	       __func__, addr, reg, val);
837 #endif
838 
839 	i2c_write(addr, reg, 1, &val, 1);
840 }
841 
842 /*
843  * Functions for setting the current I2C bus and its speed
844  */
845 
846 /*
847  * i2c_set_bus_num:
848  *
849  *  Change the active I2C bus.  Subsequent read/write calls will
850  *  go to this one.
851  *
852  *	bus - bus index, zero based
853  *
854  *	Returns: 0 on success, not 0 on failure
855  *
856  */
857 int i2c_set_bus_num(unsigned int bus);
858 
859 /*
860  * i2c_get_bus_num:
861  *
862  *  Returns index of currently active I2C bus.  Zero-based.
863  */
864 
865 unsigned int i2c_get_bus_num(void);
866 
867 /*
868  * i2c_set_bus_speed:
869  *
870  *  Change the speed of the active I2C bus
871  *
872  *	speed - bus speed in Hz
873  *
874  *	Returns: 0 on success, not 0 on failure
875  *
876  */
877 int i2c_set_bus_speed(unsigned int);
878 
879 /*
880  * i2c_get_bus_speed:
881  *
882  *  Returns speed of currently active I2C bus in Hz
883  */
884 
885 unsigned int i2c_get_bus_speed(void);
886 #endif /* CONFIG_SYS_I2C */
887 
888 /*
889  * only for backwardcompatibility, should go away if we switched
890  * completely to new multibus support.
891  */
892 #if defined(CONFIG_SYS_I2C) || defined(CONFIG_I2C_MULTI_BUS)
893 # if !defined(CONFIG_SYS_MAX_I2C_BUS)
894 #  define CONFIG_SYS_MAX_I2C_BUS		2
895 # endif
896 # define I2C_MULTI_BUS				1
897 #else
898 # define CONFIG_SYS_MAX_I2C_BUS		1
899 # define I2C_MULTI_BUS				0
900 #endif
901 
902 /* NOTE: These two functions MUST be always_inline to avoid code growth! */
903 static inline unsigned int I2C_GET_BUS(void) __attribute__((always_inline));
904 static inline unsigned int I2C_GET_BUS(void)
905 {
906 	return I2C_MULTI_BUS ? i2c_get_bus_num() : 0;
907 }
908 
909 static inline void I2C_SET_BUS(unsigned int bus) __attribute__((always_inline));
910 static inline void I2C_SET_BUS(unsigned int bus)
911 {
912 	if (I2C_MULTI_BUS)
913 		i2c_set_bus_num(bus);
914 }
915 
916 /* Multi I2C definitions */
917 enum {
918 	I2C_0, I2C_1, I2C_2, I2C_3, I2C_4, I2C_5, I2C_6, I2C_7,
919 	I2C_8, I2C_9, I2C_10,
920 };
921 
922 /**
923  * Get FDT values for i2c bus.
924  *
925  * @param blob  Device tree blbo
926  * @return the number of I2C bus
927  */
928 void board_i2c_init(const void *blob);
929 
930 /**
931  * Find the I2C bus number by given a FDT I2C node.
932  *
933  * @param blob  Device tree blbo
934  * @param node  FDT I2C node to find
935  * @return the number of I2C bus (zero based), or -1 on error
936  */
937 int i2c_get_bus_num_fdt(int node);
938 
939 /**
940  * Reset the I2C bus represented by the given a FDT I2C node.
941  *
942  * @param blob  Device tree blbo
943  * @param node  FDT I2C node to find
944  * @return 0 if port was reset, -1 if not found
945  */
946 int i2c_reset_port_fdt(const void *blob, int node);
947 
948 #endif /* !CONFIG_DM_I2C */
949 
950 #endif	/* _I2C_H_ */
951