ddbridge-i2c.h

  1/* SPDX-License-Identifier: GPL-2.0 */
  2/*
  3 * ddbridge-i2c.h: Digital Devices bridge i2c driver
  4 *
  5 * Copyright (C) 2010-2017 Digital Devices GmbH
  6 *                         Ralph Metzler <rjkm@metzlerbros.de>
  7 *                         Marcus Metzler <mocm@metzlerbros.de>
  8 */
  9
 10#ifndef __DDBRIDGE_I2C_H__
 11#define __DDBRIDGE_I2C_H__
 12
 13#include <linux/i2c.h>
 14
 15#include "ddbridge.h"
 16
 17/******************************************************************************/
 18
 19void ddb_i2c_release(struct ddb *dev);
 20int ddb_i2c_init(struct ddb *dev);
 21
 22/******************************************************************************/
 23
 24static int __maybe_unused i2c_io(struct i2c_adapter *adapter, u8 adr,
 25				 u8 *wbuf, u32 wlen, u8 *rbuf, u32 rlen)
 26{
 27	struct i2c_msg msgs[2] = { { .addr = adr,  .flags = 0,
 28				     .buf  = wbuf, .len   = wlen },
 29				   { .addr = adr,  .flags = I2C_M_RD,
 30				     .buf  = rbuf, .len   = rlen } };
 31
 32	return (i2c_transfer(adapter, msgs, 2) == 2) ? 0 : -1;
 33}
 34
 35static int __maybe_unused i2c_write(struct i2c_adapter *adap, u8 adr,
 36				    u8 *data, int len)
 37{
 38	struct i2c_msg msg = { .addr = adr, .flags = 0,
 39			       .buf = data, .len = len };
 40
 41	return (i2c_transfer(adap, &msg, 1) == 1) ? 0 : -1;
 42}
 43
 44static int __maybe_unused i2c_read(struct i2c_adapter *adapter, u8 adr, u8 *val)
 45{
 46	struct i2c_msg msgs[1] = { { .addr = adr, .flags = I2C_M_RD,
 47				     .buf  = val, .len   = 1 } };
 48
 49	return (i2c_transfer(adapter, msgs, 1) == 1) ? 0 : -1;
 50}
 51
 52static int __maybe_unused i2c_read_regs(struct i2c_adapter *adapter,
 53					u8 adr, u8 reg, u8 *val, u8 len)
 54{
 55	struct i2c_msg msgs[2] = { { .addr = adr,  .flags = 0,
 56				     .buf  = &reg, .len   = 1 },
 57				   { .addr = adr,  .flags = I2C_M_RD,
 58				     .buf  = val,  .len   = len } };
 59
 60	return (i2c_transfer(adapter, msgs, 2) == 2) ? 0 : -1;
 61}
 62
 63static int __maybe_unused i2c_read_regs16(struct i2c_adapter *adapter,
 64					  u8 adr, u16 reg, u8 *val, u8 len)
 65{
 66	u8 msg[2] = { reg >> 8, reg & 0xff };
 67	struct i2c_msg msgs[2] = { { .addr = adr, .flags = 0,
 68				     .buf  = msg, .len   = 2 },
 69				   { .addr = adr, .flags = I2C_M_RD,
 70				     .buf  = val, .len   = len } };
 71
 72	return (i2c_transfer(adapter, msgs, 2) == 2) ? 0 : -1;
 73}
 74
 75static int __maybe_unused i2c_write_reg16(struct i2c_adapter *adap,
 76					  u8 adr, u16 reg, u8 val)
 77{
 78	u8 msg[3] = { reg >> 8, reg & 0xff, val };
 79
 80	return i2c_write(adap, adr, msg, 3);
 81}
 82
 83static int __maybe_unused i2c_write_reg(struct i2c_adapter *adap,
 84					u8 adr, u8 reg, u8 val)
 85{
 86	u8 msg[2] = { reg, val };
 87
 88	return i2c_write(adap, adr, msg, 2);
 89}
 90
 91static int __maybe_unused i2c_read_reg16(struct i2c_adapter *adapter,
 92					 u8 adr, u16 reg, u8 *val)
 93{
 94	return i2c_read_regs16(adapter, adr, reg, val, 1);
 95}
 96
 97static int __maybe_unused i2c_read_reg(struct i2c_adapter *adapter,
 98				       u8 adr, u8 reg, u8 *val)
 99{
100	return i2c_read_regs(adapter, adr, reg, val, 1);
101}
102
103#endif /* __DDBRIDGE_I2C_H__ */