1 /* SPDX-License-Identifier: GPL-2.0+ */
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.
8 * Gerald Van Baren, Custom IDEAS, vanbaren@cideas.com.
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.
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.
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 */
35 * struct dm_i2c_chip - information about an i2c chip
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.
40 * To obtain this structure, use dev_get_parent_platdata(dev) where dev is
41 * the chip to examine.
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)
61 * struct dm_i2c_bus- information about an i2c bus
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
67 * To obtain this structure, use dev_get_uclass_priv(bus) where bus is the
70 * @speed_hz: Bus speed in hertz (typically 100000)
71 * @max_transaction_bytes: Maximal size of single I2C transfer
75 int max_transaction_bytes;
79 * Not all of these flags are implemented in the U-Boot API
81 enum dm_i2c_msg_flags {
82 I2C_M_TEN = 0x0010, /* ten-bit chip address */
83 I2C_M_RD = 0x0001, /* read data, from slave to master */
84 I2C_M_STOP = 0x8000, /* send stop after this message */
85 I2C_M_NOSTART = 0x4000, /* no start before this message */
86 I2C_M_REV_DIR_ADDR = 0x2000, /* invert polarity of R/W bit */
87 I2C_M_IGNORE_NAK = 0x1000, /* continue after NAK */
88 I2C_M_NO_RD_ACK = 0x0800, /* skip the Ack bit on reads */
89 I2C_M_RECV_LEN = 0x0400, /* length is first received byte */
93 * struct i2c_msg - an I2C message
95 * @addr: Slave address
96 * @flags: Flags (see enum dm_i2c_msg_flags)
97 * @len: Length of buffer in bytes, may be 0 for a probe
98 * @buf: Buffer to send/receive, or NULL if no data
108 * struct i2c_msg_list - a list of I2C messages
110 * This is called i2c_rdwr_ioctl_data in Linux but the name does not seem
111 * appropriate in U-Boot.
113 * @msg: Pointer to i2c_msg array
114 * @nmsgs: Number of elements in the array
116 struct i2c_msg_list {
117 struct i2c_msg *msgs;
122 * dm_i2c_read() - read bytes from an I2C chip
124 * To obtain an I2C device (called a 'chip') given the I2C bus address you
125 * can use i2c_get_chip(). To obtain a bus by bus number use
126 * uclass_get_device_by_seq(UCLASS_I2C, <bus number>).
128 * To set the address length of a devce use i2c_set_addr_len(). It
131 * @dev: Chip to read from
132 * @offset: Offset within chip to start reading
133 * @buffer: Place to put data
134 * @len: Number of bytes to read
136 * @return 0 on success, -ve on failure
138 int dm_i2c_read(struct udevice *dev, uint offset, uint8_t *buffer, int len);
141 * dm_i2c_write() - write bytes to an I2C chip
143 * See notes for dm_i2c_read() above.
145 * @dev: Chip to write to
146 * @offset: Offset within chip to start writing
147 * @buffer: Buffer containing data to write
148 * @len: Number of bytes to write
150 * @return 0 on success, -ve on failure
152 int dm_i2c_write(struct udevice *dev, uint offset, const uint8_t *buffer,
156 * dm_i2c_probe() - probe a particular chip address
158 * This can be useful to check for the existence of a chip on the bus.
159 * It is typically implemented by writing the chip address to the bus
160 * and checking that the chip replies with an ACK.
163 * @chip_addr: 7-bit address to probe (10-bit and others are not supported)
164 * @chip_flags: Flags for the probe (see enum dm_i2c_chip_flags)
165 * @devp: Returns the device found, or NULL if none
166 * @return 0 if a chip was found at that address, -ve if not
168 int dm_i2c_probe(struct udevice *bus, uint chip_addr, uint chip_flags,
169 struct udevice **devp);
172 * dm_i2c_reg_read() - Read a value from an I2C register
174 * This reads a single value from the given address in an I2C chip
176 * @dev: Device to use for transfer
177 * @addr: Address to read from
178 * @return value read, or -ve on error
180 int dm_i2c_reg_read(struct udevice *dev, uint offset);
183 * dm_i2c_reg_write() - Write a value to an I2C register
185 * This writes a single value to the given address in an I2C chip
187 * @dev: Device to use for transfer
188 * @addr: Address to write to
189 * @val: Value to write (normally a byte)
190 * @return 0 on success, -ve on error
192 int dm_i2c_reg_write(struct udevice *dev, uint offset, unsigned int val);
195 * dm_i2c_xfer() - Transfer messages over I2C
197 * This transfers a raw message. It is best to use dm_i2c_reg_read/write()
200 * @dev: Device to use for transfer
201 * @msg: List of messages to transfer
202 * @nmsgs: Number of messages to transfer
203 * @return 0 on success, -ve on error
205 int dm_i2c_xfer(struct udevice *dev, struct i2c_msg *msg, int nmsgs);
208 * dm_i2c_set_bus_speed() - set the speed of a bus
210 * @bus: Bus to adjust
211 * @speed: Requested speed in Hz
212 * @return 0 if OK, -EINVAL for invalid values
214 int dm_i2c_set_bus_speed(struct udevice *bus, unsigned int speed);
217 * dm_i2c_get_bus_speed() - get the speed of a bus
220 * @return speed of selected I2C bus in Hz, -ve on error
222 int dm_i2c_get_bus_speed(struct udevice *bus);
225 * i2c_set_chip_flags() - set flags for a chip
227 * Typically addresses are 7 bits, but for 10-bit addresses you should set
228 * flags to DM_I2C_CHIP_10BIT. All accesses will then use 10-bit addressing.
230 * @dev: Chip to adjust
232 * @return 0 if OK, -EINVAL if value is unsupported, other -ve value on error
234 int i2c_set_chip_flags(struct udevice *dev, uint flags);
237 * i2c_get_chip_flags() - get flags for a chip
239 * @dev: Chip to check
240 * @flagsp: Place to put flags
241 * @return 0 if OK, other -ve value on error
243 int i2c_get_chip_flags(struct udevice *dev, uint *flagsp);
246 * i2c_set_offset_len() - set the offset length for a chip
248 * The offset used to access a chip may be up to 4 bytes long. Typically it
249 * is only 1 byte, which is enough for chips with 256 bytes of memory or
250 * registers. The default value is 1, but you can call this function to
253 * @offset_len: New offset length value (typically 1 or 2)
255 int i2c_set_chip_offset_len(struct udevice *dev, uint offset_len);
258 * i2c_get_offset_len() - get the offset length for a chip
260 * @return: Current offset length value (typically 1 or 2)
262 int i2c_get_chip_offset_len(struct udevice *dev);
265 * i2c_deblock() - recover a bus that is in an unknown state
267 * See the deblock() method in 'struct dm_i2c_ops' for full information
269 * @bus: Bus to recover
270 * @return 0 if OK, -ve on error
272 int i2c_deblock(struct udevice *bus);
274 #ifdef CONFIG_DM_I2C_COMPAT
276 * i2c_probe() - Compatibility function for driver model
278 * Calls dm_i2c_probe() on the current bus
280 int i2c_probe(uint8_t chip_addr);
283 * i2c_read() - Compatibility function for driver model
285 * Calls dm_i2c_read() with the device corresponding to @chip_addr, and offset
286 * set to @addr. @alen must match the current setting for the device.
288 int i2c_read(uint8_t chip_addr, unsigned int addr, int alen, uint8_t *buffer,
292 * i2c_write() - Compatibility function for driver model
294 * Calls dm_i2c_write() with the device corresponding to @chip_addr, and offset
295 * set to @addr. @alen must match the current setting for the device.
297 int i2c_write(uint8_t chip_addr, unsigned int addr, int alen, uint8_t *buffer,
301 * i2c_get_bus_num_fdt() - Compatibility function for driver model
303 * @return the bus number associated with the given device tree node
305 int i2c_get_bus_num_fdt(int node);
308 * i2c_get_bus_num() - Compatibility function for driver model
310 * @return the 'current' bus number
312 unsigned int i2c_get_bus_num(void);
315 * i2c_set_bus_num() - Compatibility function for driver model
317 * Sets the 'current' bus
319 int i2c_set_bus_num(unsigned int bus);
321 static inline void I2C_SET_BUS(unsigned int bus)
323 i2c_set_bus_num(bus);
326 static inline unsigned int I2C_GET_BUS(void)
328 return i2c_get_bus_num();
332 * i2c_init() - Compatibility function for driver model
334 * This function does nothing.
336 void i2c_init(int speed, int slaveaddr);
339 * board_i2c_init() - Compatibility function for driver model
341 * @param blob Device tree blbo
342 * @return the number of I2C bus
344 void board_i2c_init(const void *blob);
347 * Compatibility functions for driver model.
349 uint8_t i2c_reg_read(uint8_t addr, uint8_t reg);
350 void i2c_reg_write(uint8_t addr, uint8_t reg, uint8_t val);
355 * struct dm_i2c_ops - driver operations for I2C uclass
357 * Drivers should support these operations unless otherwise noted. These
358 * operations are intended to be used by uclass code, not directly from
363 * xfer() - transfer a list of I2C messages
365 * @bus: Bus to read from
366 * @msg: List of messages to transfer
367 * @nmsgs: Number of messages in the list
368 * @return 0 if OK, -EREMOTEIO if the slave did not ACK a byte,
369 * -ECOMM if the speed cannot be supported, -EPROTO if the chip
370 * flags cannot be supported, other -ve value on some other error
372 int (*xfer)(struct udevice *bus, struct i2c_msg *msg, int nmsgs);
375 * probe_chip() - probe for the presense of a chip address
377 * This function is optional. If omitted, the uclass will send a zero
378 * length message instead.
381 * @chip_addr: Chip address to probe
382 * @chip_flags: Probe flags (enum dm_i2c_chip_flags)
383 * @return 0 if chip was found, -EREMOTEIO if not, -ENOSYS to fall back
384 * to default probem other -ve value on error
386 int (*probe_chip)(struct udevice *bus, uint chip_addr, uint chip_flags);
389 * set_bus_speed() - set the speed of a bus (optional)
391 * The bus speed value will be updated by the uclass if this function
392 * does not return an error. This method is optional - if it is not
393 * provided then the driver can read the speed from
394 * dev_get_uclass_priv(bus)->speed_hz
396 * @bus: Bus to adjust
397 * @speed: Requested speed in Hz
398 * @return 0 if OK, -EINVAL for invalid values
400 int (*set_bus_speed)(struct udevice *bus, unsigned int speed);
403 * get_bus_speed() - get the speed of a bus (optional)
405 * Normally this can be provided by the uclass, but if you want your
406 * driver to check the bus speed by looking at the hardware, you can
407 * implement that here. This method is optional. This method would
408 * normally be expected to return dev_get_uclass_priv(bus)->speed_hz.
411 * @return speed of selected I2C bus in Hz, -ve on error
413 int (*get_bus_speed)(struct udevice *bus);
416 * set_flags() - set the flags for a chip (optional)
418 * This is generally implemented by the uclass, but drivers can
419 * check the value to ensure that unsupported options are not used.
420 * This method is optional. If provided, this method will always be
421 * called when the flags change.
423 * @dev: Chip to adjust
424 * @flags: New flags value
425 * @return 0 if OK, -EINVAL if value is unsupported
427 int (*set_flags)(struct udevice *dev, uint flags);
430 * deblock() - recover a bus that is in an unknown state
432 * I2C is a synchronous protocol and resets of the processor in the
433 * middle of an access can block the I2C Bus until a powerdown of
434 * the full unit is done. This is because slaves can be stuck
435 * waiting for addition bus transitions for a transaction that will
436 * never complete. Resetting the I2C master does not help. The only
437 * way is to force the bus through a series of transitions to make
438 * sure that all slaves are done with the transaction. This method
439 * performs this 'deblocking' if support by the driver.
441 * This method is optional.
443 int (*deblock)(struct udevice *bus);
446 #define i2c_get_ops(dev) ((struct dm_i2c_ops *)(dev)->driver->ops)
449 * struct i2c_mux_ops - operations for an I2C mux
451 * The current mux state is expected to be stored in the mux itself since
452 * it is the only thing that knows how to make things work. The mux can
453 * record the current state and then avoid switching unless it is necessary.
454 * So select() can be skipped if the mux is already in the correct state.
455 * Also deselect() can be made a nop if required.
459 * select() - select one of of I2C buses attached to a mux
461 * This will be called when there is no bus currently selected by the
462 * mux. This method does not need to deselect the old bus since
463 * deselect() will be already have been called if necessary.
466 * @bus: I2C bus to select
467 * @channel: Channel number correponding to the bus to select
468 * @return 0 if OK, -ve on error
470 int (*select)(struct udevice *mux, struct udevice *bus, uint channel);
473 * deselect() - select one of of I2C buses attached to a mux
475 * This is used to deselect the currently selected I2C bus.
478 * @bus: I2C bus to deselect
479 * @channel: Channel number correponding to the bus to deselect
480 * @return 0 if OK, -ve on error
482 int (*deselect)(struct udevice *mux, struct udevice *bus, uint channel);
485 #define i2c_mux_get_ops(dev) ((struct i2c_mux_ops *)(dev)->driver->ops)
488 * i2c_get_chip() - get a device to use to access a chip on a bus
490 * This returns the device for the given chip address. The device can then
491 * be used with calls to i2c_read(), i2c_write(), i2c_probe(), etc.
493 * @bus: Bus to examine
494 * @chip_addr: Chip address for the new device
495 * @offset_len: Length of a register offset in bytes (normally 1)
496 * @devp: Returns pointer to new device if found or -ENODEV if not
499 int i2c_get_chip(struct udevice *bus, uint chip_addr, uint offset_len,
500 struct udevice **devp);
503 * i2c_get_chip_for_busnum() - get a device to use to access a chip on
506 * This returns the device for the given chip address on a particular bus
509 * @busnum: Bus number to examine
510 * @chip_addr: Chip address for the new device
511 * @offset_len: Length of a register offset in bytes (normally 1)
512 * @devp: Returns pointer to new device if found or -ENODEV if not
515 int i2c_get_chip_for_busnum(int busnum, int chip_addr, uint offset_len,
516 struct udevice **devp);
519 * i2c_chip_ofdata_to_platdata() - Decode standard I2C platform data
521 * This decodes the chip address from a device tree node and puts it into
522 * its dm_i2c_chip structure. This should be called in your driver's
523 * ofdata_to_platdata() method.
525 * @blob: Device tree blob
526 * @node: Node offset to read from
527 * @spi: Place to put the decoded information
529 int i2c_chip_ofdata_to_platdata(struct udevice *dev, struct dm_i2c_chip *chip);
532 * i2c_dump_msgs() - Dump a list of I2C messages
534 * This may be useful for debugging.
536 * @msg: Message list to dump
537 * @nmsgs: Number of messages
539 void i2c_dump_msgs(struct i2c_msg *msg, int nmsgs);
542 * i2c_emul_find() - Find an emulator for an i2c sandbox device
544 * This looks at the device's 'emul' phandle
546 * @dev: Device to find an emulator for
547 * @emulp: Returns the associated emulator, if found *
548 * @return 0 if OK, -ENOENT or -ENODEV if not found
550 int i2c_emul_find(struct udevice *dev, struct udevice **emulp);
553 * i2c_emul_get_device() - Find the device being emulated
555 * Given an emulator this returns the associated device
557 * @emul: Emulator for the device
558 * @return device that @emul is emulating
560 struct udevice *i2c_emul_get_device(struct udevice *emul);
562 #ifndef CONFIG_DM_I2C
565 * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
567 * The implementation MUST NOT use static or global variables if the
568 * I2C routines are used to read SDRAM configuration information
569 * because this is done before the memories are initialized. Limited
570 * use of stack-based variables are OK (the initial stack size is
573 * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
577 * Configuration items.
579 #define I2C_RXTX_LEN 128 /* maximum tx/rx buffer length */
581 #if !defined(CONFIG_SYS_I2C_MAX_HOPS)
582 /* no muxes used bus = i2c adapters */
583 #define CONFIG_SYS_I2C_DIRECT_BUS 1
584 #define CONFIG_SYS_I2C_MAX_HOPS 0
585 #define CONFIG_SYS_NUM_I2C_BUSES ll_entry_count(struct i2c_adapter, i2c)
587 /* we use i2c muxes */
588 #undef CONFIG_SYS_I2C_DIRECT_BUS
591 /* define the I2C bus number for RTC and DTT if not already done */
592 #if !defined(CONFIG_SYS_RTC_BUS_NUM)
593 #define CONFIG_SYS_RTC_BUS_NUM 0
595 #if !defined(CONFIG_SYS_SPD_BUS_NUM)
596 #define CONFIG_SYS_SPD_BUS_NUM 0
600 void (*init)(struct i2c_adapter *adap, int speed,
602 int (*probe)(struct i2c_adapter *adap, uint8_t chip);
603 int (*read)(struct i2c_adapter *adap, uint8_t chip,
604 uint addr, int alen, uint8_t *buffer,
606 int (*write)(struct i2c_adapter *adap, uint8_t chip,
607 uint addr, int alen, uint8_t *buffer,
609 uint (*set_bus_speed)(struct i2c_adapter *adap,
619 #define U_BOOT_I2C_MKENT_COMPLETE(_init, _probe, _read, _write, \
620 _set_speed, _speed, _slaveaddr, _hwadapnr, _name) \
626 .set_bus_speed = _set_speed, \
628 .slaveaddr = _slaveaddr, \
630 .hwadapnr = _hwadapnr, \
634 #define U_BOOT_I2C_ADAP_COMPLETE(_name, _init, _probe, _read, _write, \
635 _set_speed, _speed, _slaveaddr, _hwadapnr) \
636 ll_entry_declare(struct i2c_adapter, _name, i2c) = \
637 U_BOOT_I2C_MKENT_COMPLETE(_init, _probe, _read, _write, \
638 _set_speed, _speed, _slaveaddr, _hwadapnr, _name);
640 struct i2c_adapter *i2c_get_adapter(int index);
642 #ifndef CONFIG_SYS_I2C_DIRECT_BUS
648 struct i2c_next_hop {
654 struct i2c_bus_hose {
656 struct i2c_next_hop next_hop[CONFIG_SYS_I2C_MAX_HOPS];
658 #define I2C_NULL_HOP {{-1, ""}, 0, 0}
659 extern struct i2c_bus_hose i2c_bus[];
661 #define I2C_ADAPTER(bus) i2c_bus[bus].adapter
663 #define I2C_ADAPTER(bus) bus
665 #define I2C_BUS gd->cur_i2c_bus
667 #define I2C_ADAP_NR(bus) i2c_get_adapter(I2C_ADAPTER(bus))
668 #define I2C_ADAP I2C_ADAP_NR(gd->cur_i2c_bus)
669 #define I2C_ADAP_HWNR (I2C_ADAP->hwadapnr)
671 #ifndef CONFIG_SYS_I2C_DIRECT_BUS
672 #define I2C_MUX_PCA9540_ID 1
673 #define I2C_MUX_PCA9540 {I2C_MUX_PCA9540_ID, "PCA9540B"}
674 #define I2C_MUX_PCA9542_ID 2
675 #define I2C_MUX_PCA9542 {I2C_MUX_PCA9542_ID, "PCA9542A"}
676 #define I2C_MUX_PCA9544_ID 3
677 #define I2C_MUX_PCA9544 {I2C_MUX_PCA9544_ID, "PCA9544A"}
678 #define I2C_MUX_PCA9547_ID 4
679 #define I2C_MUX_PCA9547 {I2C_MUX_PCA9547_ID, "PCA9547A"}
680 #define I2C_MUX_PCA9548_ID 5
681 #define I2C_MUX_PCA9548 {I2C_MUX_PCA9548_ID, "PCA9548"}
684 #ifndef I2C_SOFT_DECLARATIONS
685 # if (defined(CONFIG_AT91RM9200) || \
686 defined(CONFIG_AT91SAM9260) || defined(CONFIG_AT91SAM9261) || \
687 defined(CONFIG_AT91SAM9263))
688 # define I2C_SOFT_DECLARATIONS at91_pio_t *pio = (at91_pio_t *) ATMEL_BASE_PIOA;
690 # define I2C_SOFT_DECLARATIONS
695 * Many boards/controllers/drivers don't support an I2C slave interface so
696 * provide a default slave address for them for use in common code. A real
697 * value for CONFIG_SYS_I2C_SLAVE should be defined for any board which does
698 * support a slave interface.
700 #ifndef CONFIG_SYS_I2C_SLAVE
701 #define CONFIG_SYS_I2C_SLAVE 0xfe
705 * Initialization, must be called once on start up, may be called
706 * repeatedly to change the speed and slave addresses.
708 #ifdef CONFIG_SYS_I2C_EARLY_INIT
709 void i2c_early_init_f(void);
711 void i2c_init(int speed, int slaveaddr);
712 void i2c_init_board(void);
714 #ifdef CONFIG_SYS_I2C
718 * Returns index of currently active I2C bus. Zero-based.
720 unsigned int i2c_get_bus_num(void);
725 * Change the active I2C bus. Subsequent read/write calls will
728 * bus - bus index, zero based
730 * Returns: 0 on success, not 0 on failure
733 int i2c_set_bus_num(unsigned int bus);
738 * Initializes all I2C adapters in the system. All i2c_adap structures must
739 * be initialized beforehead with function pointers and data, including
740 * speed and slaveaddr. Returns 0 on success, non-0 on failure.
742 void i2c_init_all(void);
745 * Probe the given I2C chip address. Returns 0 if a chip responded,
748 int i2c_probe(uint8_t chip);
751 * Read/Write interface:
752 * chip: I2C chip address, range 0..127
753 * addr: Memory (register) address within the chip
754 * alen: Number of bytes to use for addr (typically 1, 2 for larger
755 * memories, 0 for register type devices with only one
757 * buffer: Where to read/write the data
758 * len: How many bytes to read/write
760 * Returns: 0 on success, not 0 on failure
762 int i2c_read(uint8_t chip, unsigned int addr, int alen,
763 uint8_t *buffer, int len);
765 int i2c_write(uint8_t chip, unsigned int addr, int alen,
766 uint8_t *buffer, int len);
769 * Utility routines to read/write registers.
771 uint8_t i2c_reg_read(uint8_t addr, uint8_t reg);
773 void i2c_reg_write(uint8_t addr, uint8_t reg, uint8_t val);
778 * Change the speed of the active I2C bus
780 * speed - bus speed in Hz
782 * Returns: new bus speed
785 unsigned int i2c_set_bus_speed(unsigned int speed);
790 * Returns speed of currently active I2C bus in Hz
793 unsigned int i2c_get_bus_speed(void);
798 * Probe the given I2C chip address. Returns 0 if a chip responded,
801 int i2c_probe(uchar chip);
804 * Read/Write interface:
805 * chip: I2C chip address, range 0..127
806 * addr: Memory (register) address within the chip
807 * alen: Number of bytes to use for addr (typically 1, 2 for larger
808 * memories, 0 for register type devices with only one
810 * buffer: Where to read/write the data
811 * len: How many bytes to read/write
813 * Returns: 0 on success, not 0 on failure
815 int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len);
816 int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len);
819 * Utility routines to read/write registers.
821 static inline u8 i2c_reg_read(u8 addr, u8 reg)
826 printf("%s: addr=0x%02x, reg=0x%02x\n", __func__, addr, reg);
829 i2c_read(addr, reg, 1, &buf, 1);
834 static inline void i2c_reg_write(u8 addr, u8 reg, u8 val)
837 printf("%s: addr=0x%02x, reg=0x%02x, val=0x%02x\n",
838 __func__, addr, reg, val);
841 i2c_write(addr, reg, 1, &val, 1);
845 * Functions for setting the current I2C bus and its speed
851 * Change the active I2C bus. Subsequent read/write calls will
854 * bus - bus index, zero based
856 * Returns: 0 on success, not 0 on failure
859 int i2c_set_bus_num(unsigned int bus);
864 * Returns index of currently active I2C bus. Zero-based.
867 unsigned int i2c_get_bus_num(void);
872 * Change the speed of the active I2C bus
874 * speed - bus speed in Hz
876 * Returns: 0 on success, not 0 on failure
879 int i2c_set_bus_speed(unsigned int);
884 * Returns speed of currently active I2C bus in Hz
887 unsigned int i2c_get_bus_speed(void);
888 #endif /* CONFIG_SYS_I2C */
891 * only for backwardcompatibility, should go away if we switched
892 * completely to new multibus support.
894 #if defined(CONFIG_SYS_I2C) || defined(CONFIG_I2C_MULTI_BUS)
895 # if !defined(CONFIG_SYS_MAX_I2C_BUS)
896 # define CONFIG_SYS_MAX_I2C_BUS 2
898 # define I2C_MULTI_BUS 1
900 # define CONFIG_SYS_MAX_I2C_BUS 1
901 # define I2C_MULTI_BUS 0
904 /* NOTE: These two functions MUST be always_inline to avoid code growth! */
905 static inline unsigned int I2C_GET_BUS(void) __attribute__((always_inline));
906 static inline unsigned int I2C_GET_BUS(void)
908 return I2C_MULTI_BUS ? i2c_get_bus_num() : 0;
911 static inline void I2C_SET_BUS(unsigned int bus) __attribute__((always_inline));
912 static inline void I2C_SET_BUS(unsigned int bus)
915 i2c_set_bus_num(bus);
918 /* Multi I2C definitions */
920 I2C_0, I2C_1, I2C_2, I2C_3, I2C_4, I2C_5, I2C_6, I2C_7,
921 I2C_8, I2C_9, I2C_10,
925 * Get FDT values for i2c bus.
927 * @param blob Device tree blbo
928 * @return the number of I2C bus
930 void board_i2c_init(const void *blob);
933 * Find the I2C bus number by given a FDT I2C node.
935 * @param blob Device tree blbo
936 * @param node FDT I2C node to find
937 * @return the number of I2C bus (zero based), or -1 on error
939 int i2c_get_bus_num_fdt(int node);
942 * Reset the I2C bus represented by the given a FDT I2C node.
944 * @param blob Device tree blbo
945 * @param node FDT I2C node to find
946 * @return 0 if port was reset, -1 if not found
948 int i2c_reset_port_fdt(const void *blob, int node);
950 #endif /* !CONFIG_DM_I2C */