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// SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
/* Copyright 2013-2019 IBM Corp. */
#ifndef __I2C_H
#define __I2C_H
struct i2c_request;
struct i2c_bus {
struct list_node link;
struct dt_node *dt_node;
uint32_t opal_id;
int (*queue_req)(struct i2c_request *req);
uint64_t (*run_req)(struct i2c_request *req);
int (*check_quirk)(void *data, struct i2c_request *req, int *rc);
void *check_quirk_data;
};
/*
* I2C specific OPAL error codes:
*
* OPAL_I2C_TIMEOUT I2C request timed out
* OPAL_I2C_INVALID_CMD New command given when old not completed yet
* OPAL_I2C_LBUS_PARITY Local bus parity error
* OPAL_I2C_BKEND_OVERRUN Writing/reading into full/empty fifo respectively
* OPAL_I2C_BKEND_ACCESS Writing/reading more data than requested
* OPAL_I2C_ARBT_LOST I2C bus is held by some other master
* OPAL_I2C_NACK_RCVD Slave is not responding back with the ACK
* OPAL_I2C_STOP_ERR Did not able to send the STOP condtion on bus
*/
struct i2c_request {
struct list_node link;
struct i2c_bus *bus;
enum i2c_operation {
I2C_READ, /* RAW read from the device without offset */
I2C_WRITE, /* RAW write to the device without offset */
SMBUS_READ, /* SMBUS protocol read from the device */
SMBUS_WRITE, /* SMBUS protocol write to the device */
} op;
int result; /* OPAL i2c error code */
uint32_t dev_addr; /* Slave device address */
uint32_t offset_bytes; /* Internal device offset */
uint32_t offset; /* Internal device offset */
uint32_t rw_len; /* Length of the data request */
void *rw_buf; /* Data request buffer */
enum i2c_request_state {
i2c_req_new, /* un-initialised */
i2c_req_queued, /* waiting in the queue */
i2c_req_done, /* request has been completed */
} req_state;
void (*completion)( /* Completion callback */
int rc, struct i2c_request *req);
void *user_data; /* Client data */
int retries;
uint64_t timeout; /* in ms */
};
/* Generic i2c */
extern void i2c_add_bus(struct i2c_bus *bus);
extern struct i2c_bus *i2c_find_bus_by_id(uint32_t opal_id);
/* not generic, but useful */
struct i2c_bus *p8_i2c_find_bus_by_port(uint32_t chip_id, int eng, int port_id);
struct dt_node *p8_i2c_add_master_node(struct dt_node *xscom, int eng_id);
struct dt_node *__p8_i2c_add_port_node(struct dt_node *master, int port_id,
uint32_t bus_speed);
struct dt_node *p8_i2c_add_port_node(struct dt_node *xscom, int eng_id,
int port_id, uint32_t bus_freq);
struct i2c_bus *p8_i2c_add_bus(uint32_t chip_id, int eng_id, int port_id,
uint32_t bus_speed);
int64_t i2c_queue_req(struct i2c_request *req);
static inline uint64_t i2c_run_req(struct i2c_request *req)
{
if (req->bus->run_req)
return req->bus->run_req(req);
return 0;
}
static inline int i2c_check_quirk(struct i2c_request *req, int *rc)
{
if (req->bus->check_quirk)
return req->bus->check_quirk(req->bus->check_quirk_data, req, rc);
return 0;
}
/* I2C synchronous request API */
int64_t i2c_request_sync(struct i2c_request *req);
int64_t i2c_request_send(int bus_id, int dev_addr, int read_write,
uint32_t offset, uint32_t offset_bytes, void* buf,
size_t buflen, int timeout);
/* P8 implementation details */
extern void p8_i2c_init(void);
extern void p8_i2c_interrupt(uint32_t chip_id);
/* P9 I2C Ownership Change OCC interrupt handler */
extern void p9_i2c_bus_owner_change(u32 chip_id);
#endif /* __I2C_H */