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__ */
104