xref: /openbmc/u-boot/include/i2c.h (revision 5485cb62c04b070e20af88ed29742d6bbbe9396d)
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  * @chip_addr_offset_mask: Mask of offset bits within chip_addr. Used for
49  *			   devices which steal addresses as part of offset.
50  *			   If offset_len is zero, then the offset is encoded
51  *			   completely within the chip address itself.
52  *			   e.g. a devce with chip address of 0x2c with 512
53  *			   registers might use the bottom bit of the address
54  *			   to indicate which half of the address space is being
55  *			   accessed while still only using 1 byte offset.
56  *			   This means it will respond to  chip address 0x2c and
57  *			   0x2d.
58  *			   A real world example is the Atmel AT24C04. It's
59  *			   datasheet explains it's usage of this addressing
60  *			   mode.
61  * @emul: Emulator for this chip address (only used for emulation)
62  */
63 struct dm_i2c_chip {
64 	uint chip_addr;
65 	uint offset_len;
66 	uint flags;
67 	uint chip_addr_offset_mask;
68 #ifdef CONFIG_SANDBOX
69 	struct udevice *emul;
70 	bool test_mode;
71 #endif
72 };
73 
74 /**
75  * struct dm_i2c_bus- information about an i2c bus
76  *
77  * An I2C bus contains 0 or more chips on it, each at its own address. The
78  * bus can operate at different speeds (measured in Hz, typically 100KHz
79  * or 400KHz).
80  *
81  * To obtain this structure, use dev_get_uclass_priv(bus) where bus is the
82  * I2C bus udevice.
83  *
84  * @speed_hz: Bus speed in hertz (typically 100000)
85  */
86 struct dm_i2c_bus {
87 	int speed_hz;
88 };
89 
90 /*
91  * Not all of these flags are implemented in the U-Boot API
92  */
93 enum dm_i2c_msg_flags {
94 	I2C_M_TEN		= 0x0010, /* ten-bit chip address */
95 	I2C_M_RD		= 0x0001, /* read data, from slave to master */
96 	I2C_M_STOP		= 0x8000, /* send stop after this message */
97 	I2C_M_NOSTART		= 0x4000, /* no start before this message */
98 	I2C_M_REV_DIR_ADDR	= 0x2000, /* invert polarity of R/W bit */
99 	I2C_M_IGNORE_NAK	= 0x1000, /* continue after NAK */
100 	I2C_M_NO_RD_ACK		= 0x0800, /* skip the Ack bit on reads */
101 	I2C_M_RECV_LEN		= 0x0400, /* length is first received byte */
102 };
103 
104 /**
105  * struct i2c_msg - an I2C message
106  *
107  * @addr:	Slave address
108  * @flags:	Flags (see enum dm_i2c_msg_flags)
109  * @len:	Length of buffer in bytes, may be 0 for a probe
110  * @buf:	Buffer to send/receive, or NULL if no data
111  */
112 struct i2c_msg {
113 	uint addr;
114 	uint flags;
115 	uint len;
116 	u8 *buf;
117 };
118 
119 /**
120  * struct i2c_msg_list - a list of I2C messages
121  *
122  * This is called i2c_rdwr_ioctl_data in Linux but the name does not seem
123  * appropriate in U-Boot.
124  *
125  * @msg:	Pointer to i2c_msg array
126  * @nmsgs:	Number of elements in the array
127  */
128 struct i2c_msg_list {
129 	struct i2c_msg *msgs;
130 	uint nmsgs;
131 };
132 
133 /**
134  * dm_i2c_read() - read bytes from an I2C chip
135  *
136  * To obtain an I2C device (called a 'chip') given the I2C bus address you
137  * can use i2c_get_chip(). To obtain a bus by bus number use
138  * uclass_get_device_by_seq(UCLASS_I2C, <bus number>).
139  *
140  * To set the address length of a devce use i2c_set_addr_len(). It
141  * defaults to 1.
142  *
143  * @dev:	Chip to read from
144  * @offset:	Offset within chip to start reading
145  * @buffer:	Place to put data
146  * @len:	Number of bytes to read
147  *
148  * @return 0 on success, -ve on failure
149  */
150 int dm_i2c_read(struct udevice *dev, uint offset, uint8_t *buffer, int len);
151 
152 /**
153  * dm_i2c_write() - write bytes to an I2C chip
154  *
155  * See notes for dm_i2c_read() above.
156  *
157  * @dev:	Chip to write to
158  * @offset:	Offset within chip to start writing
159  * @buffer:	Buffer containing data to write
160  * @len:	Number of bytes to write
161  *
162  * @return 0 on success, -ve on failure
163  */
164 int dm_i2c_write(struct udevice *dev, uint offset, const uint8_t *buffer,
165 		 int len);
166 
167 /**
168  * dm_i2c_probe() - probe a particular chip address
169  *
170  * This can be useful to check for the existence of a chip on the bus.
171  * It is typically implemented by writing the chip address to the bus
172  * and checking that the chip replies with an ACK.
173  *
174  * @bus:	Bus to probe
175  * @chip_addr:	7-bit address to probe (10-bit and others are not supported)
176  * @chip_flags:	Flags for the probe (see enum dm_i2c_chip_flags)
177  * @devp:	Returns the device found, or NULL if none
178  * @return 0 if a chip was found at that address, -ve if not
179  */
180 int dm_i2c_probe(struct udevice *bus, uint chip_addr, uint chip_flags,
181 		 struct udevice **devp);
182 
183 /**
184  * dm_i2c_reg_read() - Read a value from an I2C register
185  *
186  * This reads a single value from the given address in an I2C chip
187  *
188  * @dev:	Device to use for transfer
189  * @addr:	Address to read from
190  * @return value read, or -ve on error
191  */
192 int dm_i2c_reg_read(struct udevice *dev, uint offset);
193 
194 /**
195  * dm_i2c_reg_write() - Write a value to an I2C register
196  *
197  * This writes a single value to the given address in an I2C chip
198  *
199  * @dev:	Device to use for transfer
200  * @addr:	Address to write to
201  * @val:	Value to write (normally a byte)
202  * @return 0 on success, -ve on error
203  */
204 int dm_i2c_reg_write(struct udevice *dev, uint offset, unsigned int val);
205 
206 /**
207  * dm_i2c_xfer() - Transfer messages over I2C
208  *
209  * This transfers a raw message. It is best to use dm_i2c_reg_read/write()
210  * instead.
211  *
212  * @dev:	Device to use for transfer
213  * @msg:	List of messages to transfer
214  * @nmsgs:	Number of messages to transfer
215  * @return 0 on success, -ve on error
216  */
217 int dm_i2c_xfer(struct udevice *dev, struct i2c_msg *msg, int nmsgs);
218 
219 /**
220  * dm_i2c_set_bus_speed() - set the speed of a bus
221  *
222  * @bus:	Bus to adjust
223  * @speed:	Requested speed in Hz
224  * @return 0 if OK, -EINVAL for invalid values
225  */
226 int dm_i2c_set_bus_speed(struct udevice *bus, unsigned int speed);
227 
228 /**
229  * dm_i2c_get_bus_speed() - get the speed of a bus
230  *
231  * @bus:	Bus to check
232  * @return speed of selected I2C bus in Hz, -ve on error
233  */
234 int dm_i2c_get_bus_speed(struct udevice *bus);
235 
236 /**
237  * i2c_set_chip_flags() - set flags for a chip
238  *
239  * Typically addresses are 7 bits, but for 10-bit addresses you should set
240  * flags to DM_I2C_CHIP_10BIT. All accesses will then use 10-bit addressing.
241  *
242  * @dev:	Chip to adjust
243  * @flags:	New flags
244  * @return 0 if OK, -EINVAL if value is unsupported, other -ve value on error
245  */
246 int i2c_set_chip_flags(struct udevice *dev, uint flags);
247 
248 /**
249  * i2c_get_chip_flags() - get flags for a chip
250  *
251  * @dev:	Chip to check
252  * @flagsp:	Place to put flags
253  * @return 0 if OK, other -ve value on error
254  */
255 int i2c_get_chip_flags(struct udevice *dev, uint *flagsp);
256 
257 /**
258  * i2c_set_offset_len() - set the offset length for a chip
259  *
260  * The offset used to access a chip may be up to 4 bytes long. Typically it
261  * is only 1 byte, which is enough for chips with 256 bytes of memory or
262  * registers. The default value is 1, but you can call this function to
263  * change it.
264  *
265  * @offset_len:	New offset length value (typically 1 or 2)
266  */
267 int i2c_set_chip_offset_len(struct udevice *dev, uint offset_len);
268 
269 /**
270  * i2c_get_offset_len() - get the offset length for a chip
271  *
272  * @return:	Current offset length value (typically 1 or 2)
273  */
274 int i2c_get_chip_offset_len(struct udevice *dev);
275 
276 /**
277  * i2c_set_chip_addr_offset_mask() - set mask of address bits usable by offset
278  *
279  * Some devices listen on multiple chip addresses to achieve larger offsets
280  * than their single or multiple byte offsets would allow for. You can use this
281  * function to set the bits that are valid to be used for offset overflow.
282  *
283  * @mask: The mask to be used for high offset bits within address
284  * @return 0 if OK, other -ve value on error
285  */
286 int i2c_set_chip_addr_offset_mask(struct udevice *dev, uint mask);
287 
288 /*
289  * i2c_get_chip_addr_offset_mask() - get mask of address bits usable by offset
290  *
291  * @return current chip addr offset mask
292  */
293 uint i2c_get_chip_addr_offset_mask(struct udevice *dev);
294 
295 /**
296  * i2c_deblock() - recover a bus that is in an unknown state
297  *
298  * See the deblock() method in 'struct dm_i2c_ops' for full information
299  *
300  * @bus:	Bus to recover
301  * @return 0 if OK, -ve on error
302  */
303 int i2c_deblock(struct udevice *bus);
304 
305 #ifdef CONFIG_DM_I2C_COMPAT
306 /**
307  * i2c_probe() - Compatibility function for driver model
308  *
309  * Calls dm_i2c_probe() on the current bus
310  */
311 int i2c_probe(uint8_t chip_addr);
312 
313 /**
314  * i2c_read() - Compatibility function for driver model
315  *
316  * Calls dm_i2c_read() with the device corresponding to @chip_addr, and offset
317  * set to @addr. @alen must match the current setting for the device.
318  */
319 int i2c_read(uint8_t chip_addr, unsigned int addr, int alen, uint8_t *buffer,
320 	     int len);
321 
322 /**
323  * i2c_write() - Compatibility function for driver model
324  *
325  * Calls dm_i2c_write() with the device corresponding to @chip_addr, and offset
326  * set to @addr. @alen must match the current setting for the device.
327  */
328 int i2c_write(uint8_t chip_addr, unsigned int addr, int alen, uint8_t *buffer,
329 	      int len);
330 
331 /**
332  * i2c_get_bus_num_fdt() - Compatibility function for driver model
333  *
334  * @return the bus number associated with the given device tree node
335  */
336 int i2c_get_bus_num_fdt(int node);
337 
338 /**
339  * i2c_get_bus_num() - Compatibility function for driver model
340  *
341  * @return the 'current' bus number
342  */
343 unsigned int i2c_get_bus_num(void);
344 
345 /**
346  * i2c_set_bus_num() - Compatibility function for driver model
347  *
348  * Sets the 'current' bus
349  */
350 int i2c_set_bus_num(unsigned int bus);
351 
I2C_SET_BUS(unsigned int bus)352 static inline void I2C_SET_BUS(unsigned int bus)
353 {
354 	i2c_set_bus_num(bus);
355 }
356 
I2C_GET_BUS(void)357 static inline unsigned int I2C_GET_BUS(void)
358 {
359 	return i2c_get_bus_num();
360 }
361 
362 /**
363  * i2c_init() - Compatibility function for driver model
364  *
365  * This function does nothing.
366  */
367 void i2c_init(int speed, int slaveaddr);
368 
369 /**
370  * board_i2c_init() - Compatibility function for driver model
371  *
372  * @param blob  Device tree blbo
373  * @return the number of I2C bus
374  */
375 void board_i2c_init(const void *blob);
376 
377 /*
378  * Compatibility functions for driver model.
379  */
380 uint8_t i2c_reg_read(uint8_t addr, uint8_t reg);
381 void i2c_reg_write(uint8_t addr, uint8_t reg, uint8_t val);
382 
383 #endif
384 
385 /**
386  * struct dm_i2c_ops - driver operations for I2C uclass
387  *
388  * Drivers should support these operations unless otherwise noted. These
389  * operations are intended to be used by uclass code, not directly from
390  * other code.
391  */
392 struct dm_i2c_ops {
393 	/**
394 	 * xfer() - transfer a list of I2C messages
395 	 *
396 	 * @bus:	Bus to read from
397 	 * @msg:	List of messages to transfer
398 	 * @nmsgs:	Number of messages in the list
399 	 * @return 0 if OK, -EREMOTEIO if the slave did not ACK a byte,
400 	 *	-ECOMM if the speed cannot be supported, -EPROTO if the chip
401 	 *	flags cannot be supported, other -ve value on some other error
402 	 */
403 	int (*xfer)(struct udevice *bus, struct i2c_msg *msg, int nmsgs);
404 
405 	/**
406 	 * probe_chip() - probe for the presense of a chip address
407 	 *
408 	 * This function is optional. If omitted, the uclass will send a zero
409 	 * length message instead.
410 	 *
411 	 * @bus:	Bus to probe
412 	 * @chip_addr:	Chip address to probe
413 	 * @chip_flags:	Probe flags (enum dm_i2c_chip_flags)
414 	 * @return 0 if chip was found, -EREMOTEIO if not, -ENOSYS to fall back
415 	 * to default probem other -ve value on error
416 	 */
417 	int (*probe_chip)(struct udevice *bus, uint chip_addr, uint chip_flags);
418 
419 	/**
420 	 * set_bus_speed() - set the speed of a bus (optional)
421 	 *
422 	 * The bus speed value will be updated by the uclass if this function
423 	 * does not return an error. This method is optional - if it is not
424 	 * provided then the driver can read the speed from
425 	 * dev_get_uclass_priv(bus)->speed_hz
426 	 *
427 	 * @bus:	Bus to adjust
428 	 * @speed:	Requested speed in Hz
429 	 * @return 0 if OK, -EINVAL for invalid values
430 	 */
431 	int (*set_bus_speed)(struct udevice *bus, unsigned int speed);
432 
433 	/**
434 	 * get_bus_speed() - get the speed of a bus (optional)
435 	 *
436 	 * Normally this can be provided by the uclass, but if you want your
437 	 * driver to check the bus speed by looking at the hardware, you can
438 	 * implement that here. This method is optional. This method would
439 	 * normally be expected to return dev_get_uclass_priv(bus)->speed_hz.
440 	 *
441 	 * @bus:	Bus to check
442 	 * @return speed of selected I2C bus in Hz, -ve on error
443 	 */
444 	int (*get_bus_speed)(struct udevice *bus);
445 
446 	/**
447 	 * set_flags() - set the flags for a chip (optional)
448 	 *
449 	 * This is generally implemented by the uclass, but drivers can
450 	 * check the value to ensure that unsupported options are not used.
451 	 * This method is optional. If provided, this method will always be
452 	 * called when the flags change.
453 	 *
454 	 * @dev:	Chip to adjust
455 	 * @flags:	New flags value
456 	 * @return 0 if OK, -EINVAL if value is unsupported
457 	 */
458 	int (*set_flags)(struct udevice *dev, uint flags);
459 
460 	/**
461 	 * deblock() - recover a bus that is in an unknown state
462 	 *
463 	 * I2C is a synchronous protocol and resets of the processor in the
464 	 * middle of an access can block the I2C Bus until a powerdown of
465 	 * the full unit is done. This is because slaves can be stuck
466 	 * waiting for addition bus transitions for a transaction that will
467 	 * never complete. Resetting the I2C master does not help. The only
468 	 * way is to force the bus through a series of transitions to make
469 	 * sure that all slaves are done with the transaction. This method
470 	 * performs this 'deblocking' if support by the driver.
471 	 *
472 	 * This method is optional.
473 	 */
474 	int (*deblock)(struct udevice *bus);
475 };
476 
477 #define i2c_get_ops(dev)	((struct dm_i2c_ops *)(dev)->driver->ops)
478 
479 /**
480  * struct i2c_mux_ops - operations for an I2C mux
481  *
482  * The current mux state is expected to be stored in the mux itself since
483  * it is the only thing that knows how to make things work. The mux can
484  * record the current state and then avoid switching unless it is necessary.
485  * So select() can be skipped if the mux is already in the correct state.
486  * Also deselect() can be made a nop if required.
487  */
488 struct i2c_mux_ops {
489 	/**
490 	 * select() - select one of of I2C buses attached to a mux
491 	 *
492 	 * This will be called when there is no bus currently selected by the
493 	 * mux. This method does not need to deselect the old bus since
494 	 * deselect() will be already have been called if necessary.
495 	 *
496 	 * @mux:	Mux device
497 	 * @bus:	I2C bus to select
498 	 * @channel:	Channel number correponding to the bus to select
499 	 * @return 0 if OK, -ve on error
500 	 */
501 	int (*select)(struct udevice *mux, struct udevice *bus, uint channel);
502 
503 	/**
504 	 * deselect() - select one of of I2C buses attached to a mux
505 	 *
506 	 * This is used to deselect the currently selected I2C bus.
507 	 *
508 	 * @mux:	Mux device
509 	 * @bus:	I2C bus to deselect
510 	 * @channel:	Channel number correponding to the bus to deselect
511 	 * @return 0 if OK, -ve on error
512 	 */
513 	int (*deselect)(struct udevice *mux, struct udevice *bus, uint channel);
514 };
515 
516 #define i2c_mux_get_ops(dev)	((struct i2c_mux_ops *)(dev)->driver->ops)
517 
518 /**
519  * i2c_get_chip() - get a device to use to access a chip on a bus
520  *
521  * This returns the device for the given chip address. The device can then
522  * be used with calls to i2c_read(), i2c_write(), i2c_probe(), etc.
523  *
524  * @bus:	Bus to examine
525  * @chip_addr:	Chip address for the new device
526  * @offset_len:	Length of a register offset in bytes (normally 1)
527  * @devp:	Returns pointer to new device if found or -ENODEV if not
528  *		found
529  */
530 int i2c_get_chip(struct udevice *bus, uint chip_addr, uint offset_len,
531 		 struct udevice **devp);
532 
533 /**
534  * i2c_get_chip_for_busnum() - get a device to use to access a chip on
535  *			       a bus number
536  *
537  * This returns the device for the given chip address on a particular bus
538  * number.
539  *
540  * @busnum:	Bus number to examine
541  * @chip_addr:	Chip address for the new device
542  * @offset_len:	Length of a register offset in bytes (normally 1)
543  * @devp:	Returns pointer to new device if found or -ENODEV if not
544  *		found
545  */
546 int i2c_get_chip_for_busnum(int busnum, int chip_addr, uint offset_len,
547 			    struct udevice **devp);
548 
549 /**
550  * i2c_chip_ofdata_to_platdata() - Decode standard I2C platform data
551  *
552  * This decodes the chip address from a device tree node and puts it into
553  * its dm_i2c_chip structure. This should be called in your driver's
554  * ofdata_to_platdata() method.
555  *
556  * @blob:	Device tree blob
557  * @node:	Node offset to read from
558  * @spi:	Place to put the decoded information
559  */
560 int i2c_chip_ofdata_to_platdata(struct udevice *dev, struct dm_i2c_chip *chip);
561 
562 /**
563  * i2c_dump_msgs() - Dump a list of I2C messages
564  *
565  * This may be useful for debugging.
566  *
567  * @msg:	Message list to dump
568  * @nmsgs:	Number of messages
569  */
570 void i2c_dump_msgs(struct i2c_msg *msg, int nmsgs);
571 
572 /**
573  * i2c_emul_find() - Find an emulator for an i2c sandbox device
574  *
575  * This looks at the device's 'emul' phandle
576  *
577  * @dev: Device to find an emulator for
578  * @emulp: Returns the associated emulator, if found *
579  * @return 0 if OK, -ENOENT or -ENODEV if not found
580  */
581 int i2c_emul_find(struct udevice *dev, struct udevice **emulp);
582 
583 /**
584  * i2c_emul_get_device() - Find the device being emulated
585  *
586  * Given an emulator this returns the associated device
587  *
588  * @emul: Emulator for the device
589  * @return device that @emul is emulating
590  */
591 struct udevice *i2c_emul_get_device(struct udevice *emul);
592 
593 #ifndef CONFIG_DM_I2C
594 
595 /*
596  * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
597  *
598  * The implementation MUST NOT use static or global variables if the
599  * I2C routines are used to read SDRAM configuration information
600  * because this is done before the memories are initialized. Limited
601  * use of stack-based variables are OK (the initial stack size is
602  * limited).
603  *
604  * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
605  */
606 
607 /*
608  * Configuration items.
609  */
610 #define I2C_RXTX_LEN	128	/* maximum tx/rx buffer length */
611 
612 #if !defined(CONFIG_SYS_I2C_MAX_HOPS)
613 /* no muxes used bus = i2c adapters */
614 #define CONFIG_SYS_I2C_DIRECT_BUS	1
615 #define CONFIG_SYS_I2C_MAX_HOPS		0
616 #define CONFIG_SYS_NUM_I2C_BUSES	ll_entry_count(struct i2c_adapter, i2c)
617 #else
618 /* we use i2c muxes */
619 #undef CONFIG_SYS_I2C_DIRECT_BUS
620 #endif
621 
622 /* define the I2C bus number for RTC and DTT if not already done */
623 #if !defined(CONFIG_SYS_RTC_BUS_NUM)
624 #define CONFIG_SYS_RTC_BUS_NUM		0
625 #endif
626 #if !defined(CONFIG_SYS_SPD_BUS_NUM)
627 #define CONFIG_SYS_SPD_BUS_NUM		0
628 #endif
629 
630 struct i2c_adapter {
631 	void		(*init)(struct i2c_adapter *adap, int speed,
632 				int slaveaddr);
633 	int		(*probe)(struct i2c_adapter *adap, uint8_t chip);
634 	int		(*read)(struct i2c_adapter *adap, uint8_t chip,
635 				uint addr, int alen, uint8_t *buffer,
636 				int len);
637 	int		(*write)(struct i2c_adapter *adap, uint8_t chip,
638 				uint addr, int alen, uint8_t *buffer,
639 				int len);
640 	uint		(*set_bus_speed)(struct i2c_adapter *adap,
641 				uint speed);
642 	int		speed;
643 	int		waitdelay;
644 	int		slaveaddr;
645 	int		init_done;
646 	int		hwadapnr;
647 	char		*name;
648 };
649 
650 #define U_BOOT_I2C_MKENT_COMPLETE(_init, _probe, _read, _write, \
651 		_set_speed, _speed, _slaveaddr, _hwadapnr, _name) \
652 	{ \
653 		.init		=	_init, \
654 		.probe		=	_probe, \
655 		.read		=	_read, \
656 		.write		=	_write, \
657 		.set_bus_speed	=	_set_speed, \
658 		.speed		=	_speed, \
659 		.slaveaddr	=	_slaveaddr, \
660 		.init_done	=	0, \
661 		.hwadapnr	=	_hwadapnr, \
662 		.name		=	#_name \
663 };
664 
665 #define U_BOOT_I2C_ADAP_COMPLETE(_name, _init, _probe, _read, _write, \
666 			_set_speed, _speed, _slaveaddr, _hwadapnr) \
667 	ll_entry_declare(struct i2c_adapter, _name, i2c) = \
668 	U_BOOT_I2C_MKENT_COMPLETE(_init, _probe, _read, _write, \
669 		 _set_speed, _speed, _slaveaddr, _hwadapnr, _name);
670 
671 struct i2c_adapter *i2c_get_adapter(int index);
672 
673 #ifndef CONFIG_SYS_I2C_DIRECT_BUS
674 struct i2c_mux {
675 	int	id;
676 	char	name[16];
677 };
678 
679 struct i2c_next_hop {
680 	struct i2c_mux		mux;
681 	uint8_t		chip;
682 	uint8_t		channel;
683 };
684 
685 struct i2c_bus_hose {
686 	int	adapter;
687 	struct i2c_next_hop	next_hop[CONFIG_SYS_I2C_MAX_HOPS];
688 };
689 #define I2C_NULL_HOP	{{-1, ""}, 0, 0}
690 extern struct i2c_bus_hose	i2c_bus[];
691 
692 #define I2C_ADAPTER(bus)	i2c_bus[bus].adapter
693 #else
694 #define I2C_ADAPTER(bus)	bus
695 #endif
696 #define	I2C_BUS			gd->cur_i2c_bus
697 
698 #define	I2C_ADAP_NR(bus)	i2c_get_adapter(I2C_ADAPTER(bus))
699 #define	I2C_ADAP		I2C_ADAP_NR(gd->cur_i2c_bus)
700 #define I2C_ADAP_HWNR		(I2C_ADAP->hwadapnr)
701 
702 #ifndef CONFIG_SYS_I2C_DIRECT_BUS
703 #define I2C_MUX_PCA9540_ID	1
704 #define I2C_MUX_PCA9540		{I2C_MUX_PCA9540_ID, "PCA9540B"}
705 #define I2C_MUX_PCA9542_ID	2
706 #define I2C_MUX_PCA9542		{I2C_MUX_PCA9542_ID, "PCA9542A"}
707 #define I2C_MUX_PCA9544_ID	3
708 #define I2C_MUX_PCA9544		{I2C_MUX_PCA9544_ID, "PCA9544A"}
709 #define I2C_MUX_PCA9547_ID	4
710 #define I2C_MUX_PCA9547		{I2C_MUX_PCA9547_ID, "PCA9547A"}
711 #define I2C_MUX_PCA9548_ID	5
712 #define I2C_MUX_PCA9548		{I2C_MUX_PCA9548_ID, "PCA9548"}
713 #endif
714 
715 #ifndef I2C_SOFT_DECLARATIONS
716 # if (defined(CONFIG_AT91RM9200) || \
717 	defined(CONFIG_AT91SAM9260) ||  defined(CONFIG_AT91SAM9261) || \
718 	defined(CONFIG_AT91SAM9263))
719 #  define I2C_SOFT_DECLARATIONS	at91_pio_t *pio	= (at91_pio_t *) ATMEL_BASE_PIOA;
720 # else
721 #  define I2C_SOFT_DECLARATIONS
722 # endif
723 #endif
724 
725 /*
726  * Many boards/controllers/drivers don't support an I2C slave interface so
727  * provide a default slave address for them for use in common code.  A real
728  * value for CONFIG_SYS_I2C_SLAVE should be defined for any board which does
729  * support a slave interface.
730  */
731 #ifndef	CONFIG_SYS_I2C_SLAVE
732 #define	CONFIG_SYS_I2C_SLAVE	0xfe
733 #endif
734 
735 /*
736  * Initialization, must be called once on start up, may be called
737  * repeatedly to change the speed and slave addresses.
738  */
739 #ifdef CONFIG_SYS_I2C_EARLY_INIT
740 void i2c_early_init_f(void);
741 #endif
742 void i2c_init(int speed, int slaveaddr);
743 void i2c_init_board(void);
744 
745 #ifdef CONFIG_SYS_I2C
746 /*
747  * i2c_get_bus_num:
748  *
749  *  Returns index of currently active I2C bus.  Zero-based.
750  */
751 unsigned int i2c_get_bus_num(void);
752 
753 /*
754  * i2c_set_bus_num:
755  *
756  *  Change the active I2C bus.  Subsequent read/write calls will
757  *  go to this one.
758  *
759  *	bus - bus index, zero based
760  *
761  *	Returns: 0 on success, not 0 on failure
762  *
763  */
764 int i2c_set_bus_num(unsigned int bus);
765 
766 /*
767  * i2c_init_all():
768  *
769  * Initializes all I2C adapters in the system. All i2c_adap structures must
770  * be initialized beforehead with function pointers and data, including
771  * speed and slaveaddr. Returns 0 on success, non-0 on failure.
772  */
773 void i2c_init_all(void);
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(uint8_t 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(uint8_t chip, unsigned int addr, int alen,
794 				uint8_t *buffer, int len);
795 
796 int i2c_write(uint8_t chip, unsigned int addr, int alen,
797 				uint8_t *buffer, int len);
798 
799 /*
800  * Utility routines to read/write registers.
801  */
802 uint8_t i2c_reg_read(uint8_t addr, uint8_t reg);
803 
804 void i2c_reg_write(uint8_t addr, uint8_t reg, uint8_t val);
805 
806 /*
807  * i2c_set_bus_speed:
808  *
809  *  Change the speed of the active I2C bus
810  *
811  *	speed - bus speed in Hz
812  *
813  *	Returns: new bus speed
814  *
815  */
816 unsigned int i2c_set_bus_speed(unsigned int speed);
817 
818 /*
819  * i2c_get_bus_speed:
820  *
821  *  Returns speed of currently active I2C bus in Hz
822  */
823 
824 unsigned int i2c_get_bus_speed(void);
825 
826 #else
827 
828 /*
829  * Probe the given I2C chip address.  Returns 0 if a chip responded,
830  * not 0 on failure.
831  */
832 int i2c_probe(uchar chip);
833 
834 /*
835  * Read/Write interface:
836  *   chip:    I2C chip address, range 0..127
837  *   addr:    Memory (register) address within the chip
838  *   alen:    Number of bytes to use for addr (typically 1, 2 for larger
839  *              memories, 0 for register type devices with only one
840  *              register)
841  *   buffer:  Where to read/write the data
842  *   len:     How many bytes to read/write
843  *
844  *   Returns: 0 on success, not 0 on failure
845  */
846 int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len);
847 int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len);
848 
849 /*
850  * Utility routines to read/write registers.
851  */
i2c_reg_read(u8 addr,u8 reg)852 static inline u8 i2c_reg_read(u8 addr, u8 reg)
853 {
854 	u8 buf;
855 
856 #ifdef DEBUG
857 	printf("%s: addr=0x%02x, reg=0x%02x\n", __func__, addr, reg);
858 #endif
859 
860 	i2c_read(addr, reg, 1, &buf, 1);
861 
862 	return buf;
863 }
864 
i2c_reg_write(u8 addr,u8 reg,u8 val)865 static inline void i2c_reg_write(u8 addr, u8 reg, u8 val)
866 {
867 #ifdef DEBUG
868 	printf("%s: addr=0x%02x, reg=0x%02x, val=0x%02x\n",
869 	       __func__, addr, reg, val);
870 #endif
871 
872 	i2c_write(addr, reg, 1, &val, 1);
873 }
874 
875 /*
876  * Functions for setting the current I2C bus and its speed
877  */
878 
879 /*
880  * i2c_set_bus_num:
881  *
882  *  Change the active I2C bus.  Subsequent read/write calls will
883  *  go to this one.
884  *
885  *	bus - bus index, zero based
886  *
887  *	Returns: 0 on success, not 0 on failure
888  *
889  */
890 int i2c_set_bus_num(unsigned int bus);
891 
892 /*
893  * i2c_get_bus_num:
894  *
895  *  Returns index of currently active I2C bus.  Zero-based.
896  */
897 
898 unsigned int i2c_get_bus_num(void);
899 
900 /*
901  * i2c_set_bus_speed:
902  *
903  *  Change the speed of the active I2C bus
904  *
905  *	speed - bus speed in Hz
906  *
907  *	Returns: 0 on success, not 0 on failure
908  *
909  */
910 int i2c_set_bus_speed(unsigned int);
911 
912 /*
913  * i2c_get_bus_speed:
914  *
915  *  Returns speed of currently active I2C bus in Hz
916  */
917 
918 unsigned int i2c_get_bus_speed(void);
919 #endif /* CONFIG_SYS_I2C */
920 
921 /*
922  * only for backwardcompatibility, should go away if we switched
923  * completely to new multibus support.
924  */
925 #if defined(CONFIG_SYS_I2C) || defined(CONFIG_I2C_MULTI_BUS)
926 # if !defined(CONFIG_SYS_MAX_I2C_BUS)
927 #  define CONFIG_SYS_MAX_I2C_BUS		2
928 # endif
929 # define I2C_MULTI_BUS				1
930 #else
931 # define CONFIG_SYS_MAX_I2C_BUS		1
932 # define I2C_MULTI_BUS				0
933 #endif
934 
935 /* NOTE: These two functions MUST be always_inline to avoid code growth! */
936 static inline unsigned int I2C_GET_BUS(void) __attribute__((always_inline));
I2C_GET_BUS(void)937 static inline unsigned int I2C_GET_BUS(void)
938 {
939 	return I2C_MULTI_BUS ? i2c_get_bus_num() : 0;
940 }
941 
942 static inline void I2C_SET_BUS(unsigned int bus) __attribute__((always_inline));
I2C_SET_BUS(unsigned int bus)943 static inline void I2C_SET_BUS(unsigned int bus)
944 {
945 	if (I2C_MULTI_BUS)
946 		i2c_set_bus_num(bus);
947 }
948 
949 /* Multi I2C definitions */
950 enum {
951 	I2C_0, I2C_1, I2C_2, I2C_3, I2C_4, I2C_5, I2C_6, I2C_7,
952 	I2C_8, I2C_9, I2C_10,
953 };
954 
955 /**
956  * Get FDT values for i2c bus.
957  *
958  * @param blob  Device tree blbo
959  * @return the number of I2C bus
960  */
961 void board_i2c_init(const void *blob);
962 
963 /**
964  * Find the I2C bus number by given a FDT I2C node.
965  *
966  * @param blob  Device tree blbo
967  * @param node  FDT I2C node to find
968  * @return the number of I2C bus (zero based), or -1 on error
969  */
970 int i2c_get_bus_num_fdt(int node);
971 
972 /**
973  * Reset the I2C bus represented by the given a FDT I2C node.
974  *
975  * @param blob  Device tree blbo
976  * @param node  FDT I2C node to find
977  * @return 0 if port was reset, -1 if not found
978  */
979 int i2c_reset_port_fdt(const void *blob, int node);
980 
981 #endif /* !CONFIG_DM_I2C */
982 
983 #endif	/* _I2C_H_ */
984