xref: /rk3399_rockchip-uboot/include/i2c.h (revision ba3864f8037f58dd1f46cad3b76adc0a84bd33b3)
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 #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  * dm_i2c_read() - read bytes from an I2C chip
78  *
79  * To obtain an I2C device (called a 'chip') given the I2C bus address you
80  * can use i2c_get_chip(). To obtain a bus by bus number use
81  * uclass_get_device_by_seq(UCLASS_I2C, <bus number>).
82  *
83  * To set the address length of a devce use i2c_set_addr_len(). It
84  * defaults to 1.
85  *
86  * @dev:	Chip to read from
87  * @offset:	Offset within chip to start reading
88  * @buffer:	Place to put data
89  * @len:	Number of bytes to read
90  *
91  * @return 0 on success, -ve on failure
92  */
93 int dm_i2c_read(struct udevice *dev, uint offset, uint8_t *buffer, int len);
94 
95 /**
96  * dm_i2c_write() - write bytes to an I2C chip
97  *
98  * See notes for dm_i2c_read() above.
99  *
100  * @dev:	Chip to write to
101  * @offset:	Offset within chip to start writing
102  * @buffer:	Buffer containing data to write
103  * @len:	Number of bytes to write
104  *
105  * @return 0 on success, -ve on failure
106  */
107 int dm_i2c_write(struct udevice *dev, uint offset, const uint8_t *buffer,
108 		 int len);
109 
110 /**
111  * dm_i2c_probe() - probe a particular chip address
112  *
113  * This can be useful to check for the existence of a chip on the bus.
114  * It is typically implemented by writing the chip address to the bus
115  * and checking that the chip replies with an ACK.
116  *
117  * @bus:	Bus to probe
118  * @chip_addr:	7-bit address to probe (10-bit and others are not supported)
119  * @chip_flags:	Flags for the probe (see enum dm_i2c_chip_flags)
120  * @devp:	Returns the device found, or NULL if none
121  * @return 0 if a chip was found at that address, -ve if not
122  */
123 int dm_i2c_probe(struct udevice *bus, uint chip_addr, uint chip_flags,
124 		 struct udevice **devp);
125 
126 /**
127  * dm_i2c_reg_read() - Read a value from an I2C register
128  *
129  * This reads a single value from the given address in an I2C chip
130  *
131  * @addr:	Address to read from
132  * @return value read, or -ve on error
133  */
134 int dm_i2c_reg_read(struct udevice *dev, uint offset);
135 
136 /**
137  * dm_i2c_reg_write() - Write a value to an I2C register
138  *
139  * This writes a single value to the given address in an I2C chip
140  *
141  * @addr:	Address to write to
142  * @val:	Value to write (normally a byte)
143  * @return 0 on success, -ve on error
144  */
145 int dm_i2c_reg_write(struct udevice *dev, uint offset, unsigned int val);
146 
147 /**
148  * dm_i2c_set_bus_speed() - set the speed of a bus
149  *
150  * @bus:	Bus to adjust
151  * @speed:	Requested speed in Hz
152  * @return 0 if OK, -EINVAL for invalid values
153  */
154 int dm_i2c_set_bus_speed(struct udevice *bus, unsigned int speed);
155 
156 /**
157  * dm_i2c_get_bus_speed() - get the speed of a bus
158  *
159  * @bus:	Bus to check
160  * @return speed of selected I2C bus in Hz, -ve on error
161  */
162 int dm_i2c_get_bus_speed(struct udevice *bus);
163 
164 /**
165  * i2c_set_chip_flags() - set flags for a chip
166  *
167  * Typically addresses are 7 bits, but for 10-bit addresses you should set
168  * flags to DM_I2C_CHIP_10BIT. All accesses will then use 10-bit addressing.
169  *
170  * @dev:	Chip to adjust
171  * @flags:	New flags
172  * @return 0 if OK, -EINVAL if value is unsupported, other -ve value on error
173  */
174 int i2c_set_chip_flags(struct udevice *dev, uint flags);
175 
176 /**
177  * i2c_get_chip_flags() - get flags for a chip
178  *
179  * @dev:	Chip to check
180  * @flagsp:	Place to put flags
181  * @return 0 if OK, other -ve value on error
182  */
183 int i2c_get_chip_flags(struct udevice *dev, uint *flagsp);
184 
185 /**
186  * i2c_set_offset_len() - set the offset length for a chip
187  *
188  * The offset used to access a chip may be up to 4 bytes long. Typically it
189  * is only 1 byte, which is enough for chips with 256 bytes of memory or
190  * registers. The default value is 1, but you can call this function to
191  * change it.
192  *
193  * @offset_len:	New offset length value (typically 1 or 2)
194  */
195 
196 int i2c_set_chip_offset_len(struct udevice *dev, uint offset_len);
197 /**
198  * i2c_deblock() - recover a bus that is in an unknown state
199  *
200  * See the deblock() method in 'struct dm_i2c_ops' for full information
201  *
202  * @bus:	Bus to recover
203  * @return 0 if OK, -ve on error
204  */
205 int i2c_deblock(struct udevice *bus);
206 
207 #ifdef CONFIG_DM_I2C_COMPAT
208 /**
209  * i2c_probe() - Compatibility function for driver model
210  *
211  * Calls dm_i2c_probe() on the current bus
212  */
213 int i2c_probe(uint8_t chip_addr);
214 
215 /**
216  * i2c_read() - Compatibility function for driver model
217  *
218  * Calls dm_i2c_read() with the device corresponding to @chip_addr, and offset
219  * set to @addr. @alen must match the current setting for the device.
220  */
221 int i2c_read(uint8_t chip_addr, unsigned int addr, int alen, uint8_t *buffer,
222 	     int len);
223 
224 /**
225  * i2c_write() - Compatibility function for driver model
226  *
227  * Calls dm_i2c_write() with the device corresponding to @chip_addr, and offset
228  * set to @addr. @alen must match the current setting for the device.
229  */
230 int i2c_write(uint8_t chip_addr, unsigned int addr, int alen, uint8_t *buffer,
231 	      int len);
232 
233 /**
234  * i2c_get_bus_num_fdt() - Compatibility function for driver model
235  *
236  * @return the bus number associated with the given device tree node
237  */
238 int i2c_get_bus_num_fdt(int node);
239 
240 /**
241  * i2c_get_bus_num() - Compatibility function for driver model
242  *
243  * @return the 'current' bus number
244  */
245 unsigned int i2c_get_bus_num(void);
246 
247 /**
248  * i2c_set_bus_num() - Compatibility function for driver model
249  *
250  * Sets the 'current' bus
251  */
252 int i2c_set_bus_num(unsigned int bus);
253 
254 static inline void I2C_SET_BUS(unsigned int bus)
255 {
256 	i2c_set_bus_num(bus);
257 }
258 
259 static inline unsigned int I2C_GET_BUS(void)
260 {
261 	return i2c_get_bus_num();
262 }
263 
264 /**
265  * i2c_init() - Compatibility function for driver model
266  *
267  * This function does nothing.
268  */
269 void i2c_init(int speed, int slaveaddr);
270 
271 /**
272  * board_i2c_init() - Compatibility function for driver model
273  *
274  * @param blob  Device tree blbo
275  * @return the number of I2C bus
276  */
277 void board_i2c_init(const void *blob);
278 
279 #endif
280 
281 /*
282  * Not all of these flags are implemented in the U-Boot API
283  */
284 enum dm_i2c_msg_flags {
285 	I2C_M_TEN		= 0x0010, /* ten-bit chip address */
286 	I2C_M_RD		= 0x0001, /* read data, from slave to master */
287 	I2C_M_STOP		= 0x8000, /* send stop after this message */
288 	I2C_M_NOSTART		= 0x4000, /* no start before this message */
289 	I2C_M_REV_DIR_ADDR	= 0x2000, /* invert polarity of R/W bit */
290 	I2C_M_IGNORE_NAK	= 0x1000, /* continue after NAK */
291 	I2C_M_NO_RD_ACK		= 0x0800, /* skip the Ack bit on reads */
292 	I2C_M_RECV_LEN		= 0x0400, /* length is first received byte */
293 };
294 
295 /**
296  * struct i2c_msg - an I2C message
297  *
298  * @addr:	Slave address
299  * @flags:	Flags (see enum dm_i2c_msg_flags)
300  * @len:	Length of buffer in bytes, may be 0 for a probe
301  * @buf:	Buffer to send/receive, or NULL if no data
302  */
303 struct i2c_msg {
304 	uint addr;
305 	uint flags;
306 	uint len;
307 	u8 *buf;
308 };
309 
310 /**
311  * struct i2c_msg_list - a list of I2C messages
312  *
313  * This is called i2c_rdwr_ioctl_data in Linux but the name does not seem
314  * appropriate in U-Boot.
315  *
316  * @msg:	Pointer to i2c_msg array
317  * @nmsgs:	Number of elements in the array
318  */
319 struct i2c_msg_list {
320 	struct i2c_msg *msgs;
321 	uint nmsgs;
322 };
323 
324 /**
325  * struct dm_i2c_ops - driver operations for I2C uclass
326  *
327  * Drivers should support these operations unless otherwise noted. These
328  * operations are intended to be used by uclass code, not directly from
329  * other code.
330  */
331 struct dm_i2c_ops {
332 	/**
333 	 * xfer() - transfer a list of I2C messages
334 	 *
335 	 * @bus:	Bus to read from
336 	 * @msg:	List of messages to transfer
337 	 * @nmsgs:	Number of messages in the list
338 	 * @return 0 if OK, -EREMOTEIO if the slave did not ACK a byte,
339 	 *	-ECOMM if the speed cannot be supported, -EPROTO if the chip
340 	 *	flags cannot be supported, other -ve value on some other error
341 	 */
342 	int (*xfer)(struct udevice *bus, struct i2c_msg *msg, int nmsgs);
343 
344 	/**
345 	 * probe_chip() - probe for the presense of a chip address
346 	 *
347 	 * This function is optional. If omitted, the uclass will send a zero
348 	 * length message instead.
349 	 *
350 	 * @bus:	Bus to probe
351 	 * @chip_addr:	Chip address to probe
352 	 * @chip_flags:	Probe flags (enum dm_i2c_chip_flags)
353 	 * @return 0 if chip was found, -EREMOTEIO if not, -ENOSYS to fall back
354 	 * to default probem other -ve value on error
355 	 */
356 	int (*probe_chip)(struct udevice *bus, uint chip_addr, uint chip_flags);
357 
358 	/**
359 	 * set_bus_speed() - set the speed of a bus (optional)
360 	 *
361 	 * The bus speed value will be updated by the uclass if this function
362 	 * does not return an error. This method is optional - if it is not
363 	 * provided then the driver can read the speed from
364 	 * dev_get_uclass_priv(bus)->speed_hz
365 	 *
366 	 * @bus:	Bus to adjust
367 	 * @speed:	Requested speed in Hz
368 	 * @return 0 if OK, -EINVAL for invalid values
369 	 */
370 	int (*set_bus_speed)(struct udevice *bus, unsigned int speed);
371 
372 	/**
373 	 * get_bus_speed() - get the speed of a bus (optional)
374 	 *
375 	 * Normally this can be provided by the uclass, but if you want your
376 	 * driver to check the bus speed by looking at the hardware, you can
377 	 * implement that here. This method is optional. This method would
378 	 * normally be expected to return dev_get_uclass_priv(bus)->speed_hz.
379 	 *
380 	 * @bus:	Bus to check
381 	 * @return speed of selected I2C bus in Hz, -ve on error
382 	 */
383 	int (*get_bus_speed)(struct udevice *bus);
384 
385 	/**
386 	 * set_flags() - set the flags for a chip (optional)
387 	 *
388 	 * This is generally implemented by the uclass, but drivers can
389 	 * check the value to ensure that unsupported options are not used.
390 	 * This method is optional. If provided, this method will always be
391 	 * called when the flags change.
392 	 *
393 	 * @dev:	Chip to adjust
394 	 * @flags:	New flags value
395 	 * @return 0 if OK, -EINVAL if value is unsupported
396 	 */
397 	int (*set_flags)(struct udevice *dev, uint flags);
398 
399 	/**
400 	 * deblock() - recover a bus that is in an unknown state
401 	 *
402 	 * I2C is a synchronous protocol and resets of the processor in the
403 	 * middle of an access can block the I2C Bus until a powerdown of
404 	 * the full unit is done. This is because slaves can be stuck
405 	 * waiting for addition bus transitions for a transaction that will
406 	 * never complete. Resetting the I2C master does not help. The only
407 	 * way is to force the bus through a series of transitions to make
408 	 * sure that all slaves are done with the transaction. This method
409 	 * performs this 'deblocking' if support by the driver.
410 	 *
411 	 * This method is optional.
412 	 */
413 	int (*deblock)(struct udevice *bus);
414 };
415 
416 #define i2c_get_ops(dev)	((struct dm_i2c_ops *)(dev)->driver->ops)
417 
418 /**
419  * i2c_get_chip() - get a device to use to access a chip on a bus
420  *
421  * This returns the device for the given chip address. The device can then
422  * be used with calls to i2c_read(), i2c_write(), i2c_probe(), etc.
423  *
424  * @bus:	Bus to examine
425  * @chip_addr:	Chip address for the new device
426  * @offset_len:	Length of a register offset in bytes (normally 1)
427  * @devp:	Returns pointer to new device if found or -ENODEV if not
428  *		found
429  */
430 int i2c_get_chip(struct udevice *bus, uint chip_addr, uint offset_len,
431 		 struct udevice **devp);
432 
433 /**
434  * i2c_get_chip() - get a device to use to access a chip on a bus number
435  *
436  * This returns the device for the given chip address on a particular bus
437  * number.
438  *
439  * @busnum:	Bus number to examine
440  * @chip_addr:	Chip address for the new device
441  * @offset_len:	Length of a register offset in bytes (normally 1)
442  * @devp:	Returns pointer to new device if found or -ENODEV if not
443  *		found
444  */
445 int i2c_get_chip_for_busnum(int busnum, int chip_addr, uint offset_len,
446 			    struct udevice **devp);
447 
448 /**
449  * i2c_chip_ofdata_to_platdata() - Decode standard I2C platform data
450  *
451  * This decodes the chip address from a device tree node and puts it into
452  * its dm_i2c_chip structure. This should be called in your driver's
453  * ofdata_to_platdata() method.
454  *
455  * @blob:	Device tree blob
456  * @node:	Node offset to read from
457  * @spi:	Place to put the decoded information
458  */
459 int i2c_chip_ofdata_to_platdata(const void *blob, int node,
460 				struct dm_i2c_chip *chip);
461 
462 #ifndef CONFIG_DM_I2C
463 
464 /*
465  * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
466  *
467  * The implementation MUST NOT use static or global variables if the
468  * I2C routines are used to read SDRAM configuration information
469  * because this is done before the memories are initialized. Limited
470  * use of stack-based variables are OK (the initial stack size is
471  * limited).
472  *
473  * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
474  */
475 
476 /*
477  * Configuration items.
478  */
479 #define I2C_RXTX_LEN	128	/* maximum tx/rx buffer length */
480 
481 #if !defined(CONFIG_SYS_I2C_MAX_HOPS)
482 /* no muxes used bus = i2c adapters */
483 #define CONFIG_SYS_I2C_DIRECT_BUS	1
484 #define CONFIG_SYS_I2C_MAX_HOPS		0
485 #define CONFIG_SYS_NUM_I2C_BUSES	ll_entry_count(struct i2c_adapter, i2c)
486 #else
487 /* we use i2c muxes */
488 #undef CONFIG_SYS_I2C_DIRECT_BUS
489 #endif
490 
491 /* define the I2C bus number for RTC and DTT if not already done */
492 #if !defined(CONFIG_SYS_RTC_BUS_NUM)
493 #define CONFIG_SYS_RTC_BUS_NUM		0
494 #endif
495 #if !defined(CONFIG_SYS_DTT_BUS_NUM)
496 #define CONFIG_SYS_DTT_BUS_NUM		0
497 #endif
498 #if !defined(CONFIG_SYS_SPD_BUS_NUM)
499 #define CONFIG_SYS_SPD_BUS_NUM		0
500 #endif
501 
502 struct i2c_adapter {
503 	void		(*init)(struct i2c_adapter *adap, int speed,
504 				int slaveaddr);
505 	int		(*probe)(struct i2c_adapter *adap, uint8_t chip);
506 	int		(*read)(struct i2c_adapter *adap, uint8_t chip,
507 				uint addr, int alen, uint8_t *buffer,
508 				int len);
509 	int		(*write)(struct i2c_adapter *adap, uint8_t chip,
510 				uint addr, int alen, uint8_t *buffer,
511 				int len);
512 	uint		(*set_bus_speed)(struct i2c_adapter *adap,
513 				uint speed);
514 	int		speed;
515 	int		waitdelay;
516 	int		slaveaddr;
517 	int		init_done;
518 	int		hwadapnr;
519 	char		*name;
520 };
521 
522 #define U_BOOT_I2C_MKENT_COMPLETE(_init, _probe, _read, _write, \
523 		_set_speed, _speed, _slaveaddr, _hwadapnr, _name) \
524 	{ \
525 		.init		=	_init, \
526 		.probe		=	_probe, \
527 		.read		=	_read, \
528 		.write		=	_write, \
529 		.set_bus_speed	=	_set_speed, \
530 		.speed		=	_speed, \
531 		.slaveaddr	=	_slaveaddr, \
532 		.init_done	=	0, \
533 		.hwadapnr	=	_hwadapnr, \
534 		.name		=	#_name \
535 };
536 
537 #define U_BOOT_I2C_ADAP_COMPLETE(_name, _init, _probe, _read, _write, \
538 			_set_speed, _speed, _slaveaddr, _hwadapnr) \
539 	ll_entry_declare(struct i2c_adapter, _name, i2c) = \
540 	U_BOOT_I2C_MKENT_COMPLETE(_init, _probe, _read, _write, \
541 		 _set_speed, _speed, _slaveaddr, _hwadapnr, _name);
542 
543 struct i2c_adapter *i2c_get_adapter(int index);
544 
545 #ifndef CONFIG_SYS_I2C_DIRECT_BUS
546 struct i2c_mux {
547 	int	id;
548 	char	name[16];
549 };
550 
551 struct i2c_next_hop {
552 	struct i2c_mux		mux;
553 	uint8_t		chip;
554 	uint8_t		channel;
555 };
556 
557 struct i2c_bus_hose {
558 	int	adapter;
559 	struct i2c_next_hop	next_hop[CONFIG_SYS_I2C_MAX_HOPS];
560 };
561 #define I2C_NULL_HOP	{{-1, ""}, 0, 0}
562 extern struct i2c_bus_hose	i2c_bus[];
563 
564 #define I2C_ADAPTER(bus)	i2c_bus[bus].adapter
565 #else
566 #define I2C_ADAPTER(bus)	bus
567 #endif
568 #define	I2C_BUS			gd->cur_i2c_bus
569 
570 #define	I2C_ADAP_NR(bus)	i2c_get_adapter(I2C_ADAPTER(bus))
571 #define	I2C_ADAP		I2C_ADAP_NR(gd->cur_i2c_bus)
572 #define I2C_ADAP_HWNR		(I2C_ADAP->hwadapnr)
573 
574 #ifndef CONFIG_SYS_I2C_DIRECT_BUS
575 #define I2C_MUX_PCA9540_ID	1
576 #define I2C_MUX_PCA9540		{I2C_MUX_PCA9540_ID, "PCA9540B"}
577 #define I2C_MUX_PCA9542_ID	2
578 #define I2C_MUX_PCA9542		{I2C_MUX_PCA9542_ID, "PCA9542A"}
579 #define I2C_MUX_PCA9544_ID	3
580 #define I2C_MUX_PCA9544		{I2C_MUX_PCA9544_ID, "PCA9544A"}
581 #define I2C_MUX_PCA9547_ID	4
582 #define I2C_MUX_PCA9547		{I2C_MUX_PCA9547_ID, "PCA9547A"}
583 #define I2C_MUX_PCA9548_ID	5
584 #define I2C_MUX_PCA9548		{I2C_MUX_PCA9548_ID, "PCA9548"}
585 #endif
586 
587 #ifndef I2C_SOFT_DECLARATIONS
588 # if defined(CONFIG_MPC8260)
589 #  define I2C_SOFT_DECLARATIONS volatile ioport_t *iop = ioport_addr((immap_t *)CONFIG_SYS_IMMR, I2C_PORT);
590 # elif defined(CONFIG_8xx)
591 #  define I2C_SOFT_DECLARATIONS	volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
592 
593 # elif (defined(CONFIG_AT91RM9200) || \
594 	defined(CONFIG_AT91SAM9260) ||  defined(CONFIG_AT91SAM9261) || \
595 	defined(CONFIG_AT91SAM9263))
596 #  define I2C_SOFT_DECLARATIONS	at91_pio_t *pio	= (at91_pio_t *) ATMEL_BASE_PIOA;
597 # else
598 #  define I2C_SOFT_DECLARATIONS
599 # endif
600 #endif
601 
602 #ifdef CONFIG_8xx
603 /* Set default value for the I2C bus speed on 8xx. In the
604  * future, we'll define these in all 8xx board config files.
605  */
606 #ifndef	CONFIG_SYS_I2C_SPEED
607 #define	CONFIG_SYS_I2C_SPEED	50000
608 #endif
609 #endif
610 
611 /*
612  * Many boards/controllers/drivers don't support an I2C slave interface so
613  * provide a default slave address for them for use in common code.  A real
614  * value for CONFIG_SYS_I2C_SLAVE should be defined for any board which does
615  * support a slave interface.
616  */
617 #ifndef	CONFIG_SYS_I2C_SLAVE
618 #define	CONFIG_SYS_I2C_SLAVE	0xfe
619 #endif
620 
621 /*
622  * Initialization, must be called once on start up, may be called
623  * repeatedly to change the speed and slave addresses.
624  */
625 void i2c_init(int speed, int slaveaddr);
626 void i2c_init_board(void);
627 #ifdef CONFIG_SYS_I2C_BOARD_LATE_INIT
628 void i2c_board_late_init(void);
629 #endif
630 
631 #ifdef CONFIG_SYS_I2C
632 /*
633  * i2c_get_bus_num:
634  *
635  *  Returns index of currently active I2C bus.  Zero-based.
636  */
637 unsigned int i2c_get_bus_num(void);
638 
639 /*
640  * i2c_set_bus_num:
641  *
642  *  Change the active I2C bus.  Subsequent read/write calls will
643  *  go to this one.
644  *
645  *	bus - bus index, zero based
646  *
647  *	Returns: 0 on success, not 0 on failure
648  *
649  */
650 int i2c_set_bus_num(unsigned int bus);
651 
652 /*
653  * i2c_init_all():
654  *
655  * Initializes all I2C adapters in the system. All i2c_adap structures must
656  * be initialized beforehead with function pointers and data, including
657  * speed and slaveaddr. Returns 0 on success, non-0 on failure.
658  */
659 void i2c_init_all(void);
660 
661 /*
662  * Probe the given I2C chip address.  Returns 0 if a chip responded,
663  * not 0 on failure.
664  */
665 int i2c_probe(uint8_t chip);
666 
667 /*
668  * Read/Write interface:
669  *   chip:    I2C chip address, range 0..127
670  *   addr:    Memory (register) address within the chip
671  *   alen:    Number of bytes to use for addr (typically 1, 2 for larger
672  *              memories, 0 for register type devices with only one
673  *              register)
674  *   buffer:  Where to read/write the data
675  *   len:     How many bytes to read/write
676  *
677  *   Returns: 0 on success, not 0 on failure
678  */
679 int i2c_read(uint8_t chip, unsigned int addr, int alen,
680 				uint8_t *buffer, int len);
681 
682 int i2c_write(uint8_t chip, unsigned int addr, int alen,
683 				uint8_t *buffer, int len);
684 
685 /*
686  * Utility routines to read/write registers.
687  */
688 uint8_t i2c_reg_read(uint8_t addr, uint8_t reg);
689 
690 void i2c_reg_write(uint8_t addr, uint8_t reg, uint8_t val);
691 
692 /*
693  * i2c_set_bus_speed:
694  *
695  *  Change the speed of the active I2C bus
696  *
697  *	speed - bus speed in Hz
698  *
699  *	Returns: new bus speed
700  *
701  */
702 unsigned int i2c_set_bus_speed(unsigned int speed);
703 
704 /*
705  * i2c_get_bus_speed:
706  *
707  *  Returns speed of currently active I2C bus in Hz
708  */
709 
710 unsigned int i2c_get_bus_speed(void);
711 
712 /*
713  * i2c_reloc_fixup:
714  *
715  * Adjusts I2C pointers after U-Boot is relocated to DRAM
716  */
717 void i2c_reloc_fixup(void);
718 #if defined(CONFIG_SYS_I2C_SOFT)
719 void i2c_soft_init(void);
720 void i2c_soft_active(void);
721 void i2c_soft_tristate(void);
722 int i2c_soft_read(void);
723 void i2c_soft_sda(int bit);
724 void i2c_soft_scl(int bit);
725 void i2c_soft_delay(void);
726 #endif
727 #else
728 
729 /*
730  * Probe the given I2C chip address.  Returns 0 if a chip responded,
731  * not 0 on failure.
732  */
733 int i2c_probe(uchar chip);
734 
735 /*
736  * Read/Write interface:
737  *   chip:    I2C chip address, range 0..127
738  *   addr:    Memory (register) address within the chip
739  *   alen:    Number of bytes to use for addr (typically 1, 2 for larger
740  *              memories, 0 for register type devices with only one
741  *              register)
742  *   buffer:  Where to read/write the data
743  *   len:     How many bytes to read/write
744  *
745  *   Returns: 0 on success, not 0 on failure
746  */
747 int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len);
748 int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len);
749 
750 /*
751  * Utility routines to read/write registers.
752  */
753 static inline u8 i2c_reg_read(u8 addr, u8 reg)
754 {
755 	u8 buf;
756 
757 #ifdef CONFIG_8xx
758 	/* MPC8xx needs this.  Maybe one day we can get rid of it. */
759 	i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
760 #endif
761 
762 #ifdef DEBUG
763 	printf("%s: addr=0x%02x, reg=0x%02x\n", __func__, addr, reg);
764 #endif
765 
766 	i2c_read(addr, reg, 1, &buf, 1);
767 
768 	return buf;
769 }
770 
771 static inline void i2c_reg_write(u8 addr, u8 reg, u8 val)
772 {
773 #ifdef CONFIG_8xx
774 	/* MPC8xx needs this.  Maybe one day we can get rid of it. */
775 	i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
776 #endif
777 
778 #ifdef DEBUG
779 	printf("%s: addr=0x%02x, reg=0x%02x, val=0x%02x\n",
780 	       __func__, addr, reg, val);
781 #endif
782 
783 	i2c_write(addr, reg, 1, &val, 1);
784 }
785 
786 /*
787  * Functions for setting the current I2C bus and its speed
788  */
789 
790 /*
791  * i2c_set_bus_num:
792  *
793  *  Change the active I2C bus.  Subsequent read/write calls will
794  *  go to this one.
795  *
796  *	bus - bus index, zero based
797  *
798  *	Returns: 0 on success, not 0 on failure
799  *
800  */
801 int i2c_set_bus_num(unsigned int bus);
802 
803 /*
804  * i2c_get_bus_num:
805  *
806  *  Returns index of currently active I2C bus.  Zero-based.
807  */
808 
809 unsigned int i2c_get_bus_num(void);
810 
811 /*
812  * i2c_set_bus_speed:
813  *
814  *  Change the speed of the active I2C bus
815  *
816  *	speed - bus speed in Hz
817  *
818  *	Returns: 0 on success, not 0 on failure
819  *
820  */
821 int i2c_set_bus_speed(unsigned int);
822 
823 /*
824  * i2c_get_bus_speed:
825  *
826  *  Returns speed of currently active I2C bus in Hz
827  */
828 
829 unsigned int i2c_get_bus_speed(void);
830 #endif /* CONFIG_SYS_I2C */
831 
832 /*
833  * only for backwardcompatibility, should go away if we switched
834  * completely to new multibus support.
835  */
836 #if defined(CONFIG_SYS_I2C) || defined(CONFIG_I2C_MULTI_BUS)
837 # if !defined(CONFIG_SYS_MAX_I2C_BUS)
838 #  define CONFIG_SYS_MAX_I2C_BUS		2
839 # endif
840 # define I2C_MULTI_BUS				1
841 #else
842 # define CONFIG_SYS_MAX_I2C_BUS		1
843 # define I2C_MULTI_BUS				0
844 #endif
845 
846 /* NOTE: These two functions MUST be always_inline to avoid code growth! */
847 static inline unsigned int I2C_GET_BUS(void) __attribute__((always_inline));
848 static inline unsigned int I2C_GET_BUS(void)
849 {
850 	return I2C_MULTI_BUS ? i2c_get_bus_num() : 0;
851 }
852 
853 static inline void I2C_SET_BUS(unsigned int bus) __attribute__((always_inline));
854 static inline void I2C_SET_BUS(unsigned int bus)
855 {
856 	if (I2C_MULTI_BUS)
857 		i2c_set_bus_num(bus);
858 }
859 
860 /* Multi I2C definitions */
861 enum {
862 	I2C_0, I2C_1, I2C_2, I2C_3, I2C_4, I2C_5, I2C_6, I2C_7,
863 	I2C_8, I2C_9, I2C_10,
864 };
865 
866 /* Multi I2C busses handling */
867 #ifdef CONFIG_SOFT_I2C_MULTI_BUS
868 extern int get_multi_scl_pin(void);
869 extern int get_multi_sda_pin(void);
870 extern int multi_i2c_init(void);
871 #endif
872 
873 /**
874  * Get FDT values for i2c bus.
875  *
876  * @param blob  Device tree blbo
877  * @return the number of I2C bus
878  */
879 void board_i2c_init(const void *blob);
880 
881 /**
882  * Find the I2C bus number by given a FDT I2C node.
883  *
884  * @param blob  Device tree blbo
885  * @param node  FDT I2C node to find
886  * @return the number of I2C bus (zero based), or -1 on error
887  */
888 int i2c_get_bus_num_fdt(int node);
889 
890 /**
891  * Reset the I2C bus represented by the given a FDT I2C node.
892  *
893  * @param blob  Device tree blbo
894  * @param node  FDT I2C node to find
895  * @return 0 if port was reset, -1 if not found
896  */
897 int i2c_reset_port_fdt(const void *blob, int node);
898 
899 #endif /* !CONFIG_DM_I2C */
900 
901 #endif	/* _I2C_H_ */
902