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      1 /* SPDX-License-Identifier: GPL-2.0+ */
      2 /*
      3  * Copyright (C) 2009 Sergey Kubushyn <ksi (at) koi8.net>
      4  * Copyright (C) 2009 - 2013 Heiko Schocher <hs (at) denx.de>
      5  * Changes for multibus/multiadapter I2C support.
      6  *
      7  * (C) Copyright 2001
      8  * Gerald Van Baren, Custom IDEAS, vanbaren (at) cideas.com.
      9  *
     10  * The original I2C interface was
     11  *   (C) 2000 by Paolo Scaffardi (arsenio (at) 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 #ifndef CONFIG_DM_I2C
    540 
    541 /*
    542  * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
    543  *
    544  * The implementation MUST NOT use static or global variables if the
    545  * I2C routines are used to read SDRAM configuration information
    546  * because this is done before the memories are initialized. Limited
    547  * use of stack-based variables are OK (the initial stack size is
    548  * limited).
    549  *
    550  * WARNING WARNING WARNING WARNING WARNING WARNING WARNING WARNING
    551  */
    552 
    553 /*
    554  * Configuration items.
    555  */
    556 #define I2C_RXTX_LEN	128	/* maximum tx/rx buffer length */
    557 
    558 #if !defined(CONFIG_SYS_I2C_MAX_HOPS)
    559 /* no muxes used bus = i2c adapters */
    560 #define CONFIG_SYS_I2C_DIRECT_BUS	1
    561 #define CONFIG_SYS_I2C_MAX_HOPS		0
    562 #define CONFIG_SYS_NUM_I2C_BUSES	ll_entry_count(struct i2c_adapter, i2c)
    563 #else
    564 /* we use i2c muxes */
    565 #undef CONFIG_SYS_I2C_DIRECT_BUS
    566 #endif
    567 
    568 /* define the I2C bus number for RTC and DTT if not already done */
    569 #if !defined(CONFIG_SYS_RTC_BUS_NUM)
    570 #define CONFIG_SYS_RTC_BUS_NUM		0
    571 #endif
    572 #if !defined(CONFIG_SYS_SPD_BUS_NUM)
    573 #define CONFIG_SYS_SPD_BUS_NUM		0
    574 #endif
    575 
    576 struct i2c_adapter {
    577 	void		(*init)(struct i2c_adapter *adap, int speed,
    578 				int slaveaddr);
    579 	int		(*probe)(struct i2c_adapter *adap, uint8_t chip);
    580 	int		(*read)(struct i2c_adapter *adap, uint8_t chip,
    581 				uint addr, int alen, uint8_t *buffer,
    582 				int len);
    583 	int		(*write)(struct i2c_adapter *adap, uint8_t chip,
    584 				uint addr, int alen, uint8_t *buffer,
    585 				int len);
    586 	uint		(*set_bus_speed)(struct i2c_adapter *adap,
    587 				uint speed);
    588 	int		speed;
    589 	int		waitdelay;
    590 	int		slaveaddr;
    591 	int		init_done;
    592 	int		hwadapnr;
    593 	char		*name;
    594 };
    595 
    596 #define U_BOOT_I2C_MKENT_COMPLETE(_init, _probe, _read, _write, \
    597 		_set_speed, _speed, _slaveaddr, _hwadapnr, _name) \
    598 	{ \
    599 		.init		=	_init, \
    600 		.probe		=	_probe, \
    601 		.read		=	_read, \
    602 		.write		=	_write, \
    603 		.set_bus_speed	=	_set_speed, \
    604 		.speed		=	_speed, \
    605 		.slaveaddr	=	_slaveaddr, \
    606 		.init_done	=	0, \
    607 		.hwadapnr	=	_hwadapnr, \
    608 		.name		=	#_name \
    609 };
    610 
    611 #define U_BOOT_I2C_ADAP_COMPLETE(_name, _init, _probe, _read, _write, \
    612 			_set_speed, _speed, _slaveaddr, _hwadapnr) \
    613 	ll_entry_declare(struct i2c_adapter, _name, i2c) = \
    614 	U_BOOT_I2C_MKENT_COMPLETE(_init, _probe, _read, _write, \
    615 		 _set_speed, _speed, _slaveaddr, _hwadapnr, _name);
    616 
    617 struct i2c_adapter *i2c_get_adapter(int index);
    618 
    619 #ifndef CONFIG_SYS_I2C_DIRECT_BUS
    620 struct i2c_mux {
    621 	int	id;
    622 	char	name[16];
    623 };
    624 
    625 struct i2c_next_hop {
    626 	struct i2c_mux		mux;
    627 	uint8_t		chip;
    628 	uint8_t		channel;
    629 };
    630 
    631 struct i2c_bus_hose {
    632 	int	adapter;
    633 	struct i2c_next_hop	next_hop[CONFIG_SYS_I2C_MAX_HOPS];
    634 };
    635 #define I2C_NULL_HOP	{{-1, ""}, 0, 0}
    636 extern struct i2c_bus_hose	i2c_bus[];
    637 
    638 #define I2C_ADAPTER(bus)	i2c_bus[bus].adapter
    639 #else
    640 #define I2C_ADAPTER(bus)	bus
    641 #endif
    642 #define	I2C_BUS			gd->cur_i2c_bus
    643 
    644 #define	I2C_ADAP_NR(bus)	i2c_get_adapter(I2C_ADAPTER(bus))
    645 #define	I2C_ADAP		I2C_ADAP_NR(gd->cur_i2c_bus)
    646 #define I2C_ADAP_HWNR		(I2C_ADAP->hwadapnr)
    647 
    648 #ifndef CONFIG_SYS_I2C_DIRECT_BUS
    649 #define I2C_MUX_PCA9540_ID	1
    650 #define I2C_MUX_PCA9540		{I2C_MUX_PCA9540_ID, "PCA9540B"}
    651 #define I2C_MUX_PCA9542_ID	2
    652 #define I2C_MUX_PCA9542		{I2C_MUX_PCA9542_ID, "PCA9542A"}
    653 #define I2C_MUX_PCA9544_ID	3
    654 #define I2C_MUX_PCA9544		{I2C_MUX_PCA9544_ID, "PCA9544A"}
    655 #define I2C_MUX_PCA9547_ID	4
    656 #define I2C_MUX_PCA9547		{I2C_MUX_PCA9547_ID, "PCA9547A"}
    657 #define I2C_MUX_PCA9548_ID	5
    658 #define I2C_MUX_PCA9548		{I2C_MUX_PCA9548_ID, "PCA9548"}
    659 #endif
    660 
    661 #ifndef I2C_SOFT_DECLARATIONS
    662 # if (defined(CONFIG_AT91RM9200) || \
    663 	defined(CONFIG_AT91SAM9260) ||  defined(CONFIG_AT91SAM9261) || \
    664 	defined(CONFIG_AT91SAM9263))
    665 #  define I2C_SOFT_DECLARATIONS	at91_pio_t *pio	= (at91_pio_t *) ATMEL_BASE_PIOA;
    666 # else
    667 #  define I2C_SOFT_DECLARATIONS
    668 # endif
    669 #endif
    670 
    671 /*
    672  * Many boards/controllers/drivers don't support an I2C slave interface so
    673  * provide a default slave address for them for use in common code.  A real
    674  * value for CONFIG_SYS_I2C_SLAVE should be defined for any board which does
    675  * support a slave interface.
    676  */
    677 #ifndef	CONFIG_SYS_I2C_SLAVE
    678 #define	CONFIG_SYS_I2C_SLAVE	0xfe
    679 #endif
    680 
    681 /*
    682  * Initialization, must be called once on start up, may be called
    683  * repeatedly to change the speed and slave addresses.
    684  */
    685 #ifdef CONFIG_SYS_I2C_EARLY_INIT
    686 void i2c_early_init_f(void);
    687 #endif
    688 void i2c_init(int speed, int slaveaddr);
    689 void i2c_init_board(void);
    690 
    691 #ifdef CONFIG_SYS_I2C
    692 /*
    693  * i2c_get_bus_num:
    694  *
    695  *  Returns index of currently active I2C bus.  Zero-based.
    696  */
    697 unsigned int i2c_get_bus_num(void);
    698 
    699 /*
    700  * i2c_set_bus_num:
    701  *
    702  *  Change the active I2C bus.  Subsequent read/write calls will
    703  *  go to this one.
    704  *
    705  *	bus - bus index, zero based
    706  *
    707  *	Returns: 0 on success, not 0 on failure
    708  *
    709  */
    710 int i2c_set_bus_num(unsigned int bus);
    711 
    712 /*
    713  * i2c_init_all():
    714  *
    715  * Initializes all I2C adapters in the system. All i2c_adap structures must
    716  * be initialized beforehead with function pointers and data, including
    717  * speed and slaveaddr. Returns 0 on success, non-0 on failure.
    718  */
    719 void i2c_init_all(void);
    720 
    721 /*
    722  * Probe the given I2C chip address.  Returns 0 if a chip responded,
    723  * not 0 on failure.
    724  */
    725 int i2c_probe(uint8_t chip);
    726 
    727 /*
    728  * Read/Write interface:
    729  *   chip:    I2C chip address, range 0..127
    730  *   addr:    Memory (register) address within the chip
    731  *   alen:    Number of bytes to use for addr (typically 1, 2 for larger
    732  *              memories, 0 for register type devices with only one
    733  *              register)
    734  *   buffer:  Where to read/write the data
    735  *   len:     How many bytes to read/write
    736  *
    737  *   Returns: 0 on success, not 0 on failure
    738  */
    739 int i2c_read(uint8_t chip, unsigned int addr, int alen,
    740 				uint8_t *buffer, int len);
    741 
    742 int i2c_write(uint8_t chip, unsigned int addr, int alen,
    743 				uint8_t *buffer, int len);
    744 
    745 /*
    746  * Utility routines to read/write registers.
    747  */
    748 uint8_t i2c_reg_read(uint8_t addr, uint8_t reg);
    749 
    750 void i2c_reg_write(uint8_t addr, uint8_t reg, uint8_t val);
    751 
    752 /*
    753  * i2c_set_bus_speed:
    754  *
    755  *  Change the speed of the active I2C bus
    756  *
    757  *	speed - bus speed in Hz
    758  *
    759  *	Returns: new bus speed
    760  *
    761  */
    762 unsigned int i2c_set_bus_speed(unsigned int speed);
    763 
    764 /*
    765  * i2c_get_bus_speed:
    766  *
    767  *  Returns speed of currently active I2C bus in Hz
    768  */
    769 
    770 unsigned int i2c_get_bus_speed(void);
    771 
    772 #else
    773 
    774 /*
    775  * Probe the given I2C chip address.  Returns 0 if a chip responded,
    776  * not 0 on failure.
    777  */
    778 int i2c_probe(uchar chip);
    779 
    780 /*
    781  * Read/Write interface:
    782  *   chip:    I2C chip address, range 0..127
    783  *   addr:    Memory (register) address within the chip
    784  *   alen:    Number of bytes to use for addr (typically 1, 2 for larger
    785  *              memories, 0 for register type devices with only one
    786  *              register)
    787  *   buffer:  Where to read/write the data
    788  *   len:     How many bytes to read/write
    789  *
    790  *   Returns: 0 on success, not 0 on failure
    791  */
    792 int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len);
    793 int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len);
    794 
    795 /*
    796  * Utility routines to read/write registers.
    797  */
    798 static inline u8 i2c_reg_read(u8 addr, u8 reg)
    799 {
    800 	u8 buf;
    801 
    802 #ifdef DEBUG
    803 	printf("%s: addr=0x%02x, reg=0x%02x\n", __func__, addr, reg);
    804 #endif
    805 
    806 	i2c_read(addr, reg, 1, &buf, 1);
    807 
    808 	return buf;
    809 }
    810 
    811 static inline void i2c_reg_write(u8 addr, u8 reg, u8 val)
    812 {
    813 #ifdef DEBUG
    814 	printf("%s: addr=0x%02x, reg=0x%02x, val=0x%02x\n",
    815 	       __func__, addr, reg, val);
    816 #endif
    817 
    818 	i2c_write(addr, reg, 1, &val, 1);
    819 }
    820 
    821 /*
    822  * Functions for setting the current I2C bus and its speed
    823  */
    824 
    825 /*
    826  * i2c_set_bus_num:
    827  *
    828  *  Change the active I2C bus.  Subsequent read/write calls will
    829  *  go to this one.
    830  *
    831  *	bus - bus index, zero based
    832  *
    833  *	Returns: 0 on success, not 0 on failure
    834  *
    835  */
    836 int i2c_set_bus_num(unsigned int bus);
    837 
    838 /*
    839  * i2c_get_bus_num:
    840  *
    841  *  Returns index of currently active I2C bus.  Zero-based.
    842  */
    843 
    844 unsigned int i2c_get_bus_num(void);
    845 
    846 /*
    847  * i2c_set_bus_speed:
    848  *
    849  *  Change the speed of the active I2C bus
    850  *
    851  *	speed - bus speed in Hz
    852  *
    853  *	Returns: 0 on success, not 0 on failure
    854  *
    855  */
    856 int i2c_set_bus_speed(unsigned int);
    857 
    858 /*
    859  * i2c_get_bus_speed:
    860  *
    861  *  Returns speed of currently active I2C bus in Hz
    862  */
    863 
    864 unsigned int i2c_get_bus_speed(void);
    865 #endif /* CONFIG_SYS_I2C */
    866 
    867 /*
    868  * only for backwardcompatibility, should go away if we switched
    869  * completely to new multibus support.
    870  */
    871 #if defined(CONFIG_SYS_I2C) || defined(CONFIG_I2C_MULTI_BUS)
    872 # if !defined(CONFIG_SYS_MAX_I2C_BUS)
    873 #  define CONFIG_SYS_MAX_I2C_BUS		2
    874 # endif
    875 # define I2C_MULTI_BUS				1
    876 #else
    877 # define CONFIG_SYS_MAX_I2C_BUS		1
    878 # define I2C_MULTI_BUS				0
    879 #endif
    880 
    881 /* NOTE: These two functions MUST be always_inline to avoid code growth! */
    882 static inline unsigned int I2C_GET_BUS(void) __attribute__((always_inline));
    883 static inline unsigned int I2C_GET_BUS(void)
    884 {
    885 	return I2C_MULTI_BUS ? i2c_get_bus_num() : 0;
    886 }
    887 
    888 static inline void I2C_SET_BUS(unsigned int bus) __attribute__((always_inline));
    889 static inline void I2C_SET_BUS(unsigned int bus)
    890 {
    891 	if (I2C_MULTI_BUS)
    892 		i2c_set_bus_num(bus);
    893 }
    894 
    895 /* Multi I2C definitions */
    896 enum {
    897 	I2C_0, I2C_1, I2C_2, I2C_3, I2C_4, I2C_5, I2C_6, I2C_7,
    898 	I2C_8, I2C_9, I2C_10,
    899 };
    900 
    901 /**
    902  * Get FDT values for i2c bus.
    903  *
    904  * @param blob  Device tree blbo
    905  * @return the number of I2C bus
    906  */
    907 void board_i2c_init(const void *blob);
    908 
    909 /**
    910  * Find the I2C bus number by given a FDT I2C node.
    911  *
    912  * @param blob  Device tree blbo
    913  * @param node  FDT I2C node to find
    914  * @return the number of I2C bus (zero based), or -1 on error
    915  */
    916 int i2c_get_bus_num_fdt(int node);
    917 
    918 /**
    919  * Reset the I2C bus represented by the given a FDT I2C node.
    920  *
    921  * @param blob  Device tree blbo
    922  * @param node  FDT I2C node to find
    923  * @return 0 if port was reset, -1 if not found
    924  */
    925 int i2c_reset_port_fdt(const void *blob, int node);
    926 
    927 #endif /* !CONFIG_DM_I2C */
    928 
    929 #endif	/* _I2C_H_ */
    930