1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * I2C driver for Marvell 88PM860x
4 *
5 * Copyright (C) 2009 Marvell International Ltd.
6 *
7 * Author: Haojian Zhuang <haojian.zhuang@marvell.com>
8 */
9#include <linux/kernel.h>
10#include <linux/module.h>
11#include <linux/i2c.h>
12#include <linux/regmap.h>
13#include <linux/mfd/88pm860x.h>
14
15int pm860x_reg_read(struct i2c_client *i2c, int reg)
16{
17 struct pm860x_chip *chip = i2c_get_clientdata(client: i2c);
18 struct regmap *map = (i2c == chip->client) ? chip->regmap
19 : chip->regmap_companion;
20 unsigned int data;
21 int ret;
22
23 ret = regmap_read(map, reg, val: &data);
24 if (ret < 0)
25 return ret;
26 else
27 return (int)data;
28}
29EXPORT_SYMBOL(pm860x_reg_read);
30
31int pm860x_reg_write(struct i2c_client *i2c, int reg,
32 unsigned char data)
33{
34 struct pm860x_chip *chip = i2c_get_clientdata(client: i2c);
35 struct regmap *map = (i2c == chip->client) ? chip->regmap
36 : chip->regmap_companion;
37 int ret;
38
39 ret = regmap_write(map, reg, val: data);
40 return ret;
41}
42EXPORT_SYMBOL(pm860x_reg_write);
43
44int pm860x_bulk_read(struct i2c_client *i2c, int reg,
45 int count, unsigned char *buf)
46{
47 struct pm860x_chip *chip = i2c_get_clientdata(client: i2c);
48 struct regmap *map = (i2c == chip->client) ? chip->regmap
49 : chip->regmap_companion;
50 int ret;
51
52 ret = regmap_raw_read(map, reg, val: buf, val_len: count);
53 return ret;
54}
55EXPORT_SYMBOL(pm860x_bulk_read);
56
57int pm860x_bulk_write(struct i2c_client *i2c, int reg,
58 int count, unsigned char *buf)
59{
60 struct pm860x_chip *chip = i2c_get_clientdata(client: i2c);
61 struct regmap *map = (i2c == chip->client) ? chip->regmap
62 : chip->regmap_companion;
63 int ret;
64
65 ret = regmap_raw_write(map, reg, val: buf, val_len: count);
66 return ret;
67}
68EXPORT_SYMBOL(pm860x_bulk_write);
69
70int pm860x_set_bits(struct i2c_client *i2c, int reg,
71 unsigned char mask, unsigned char data)
72{
73 struct pm860x_chip *chip = i2c_get_clientdata(client: i2c);
74 struct regmap *map = (i2c == chip->client) ? chip->regmap
75 : chip->regmap_companion;
76 int ret;
77
78 ret = regmap_update_bits(map, reg, mask, val: data);
79 return ret;
80}
81EXPORT_SYMBOL(pm860x_set_bits);
82
83static int read_device(struct i2c_client *i2c, int reg,
84 int bytes, void *dest)
85{
86 unsigned char msgbuf0[I2C_SMBUS_BLOCK_MAX + 3];
87 unsigned char msgbuf1[I2C_SMBUS_BLOCK_MAX + 2];
88 struct i2c_adapter *adap = i2c->adapter;
89 struct i2c_msg msg[2] = {
90 {
91 .addr = i2c->addr,
92 .flags = 0,
93 .len = 1,
94 .buf = msgbuf0
95 },
96 { .addr = i2c->addr,
97 .flags = I2C_M_RD,
98 .len = 0,
99 .buf = msgbuf1
100 },
101 };
102 int num = 1, ret = 0;
103
104 if (dest == NULL)
105 return -EINVAL;
106 msgbuf0[0] = (unsigned char)reg; /* command */
107 msg[1].len = bytes;
108
109 /* if data needs to read back, num should be 2 */
110 if (bytes > 0)
111 num = 2;
112 ret = adap->algo->master_xfer(adap, msg, num);
113 memcpy(dest, msgbuf1, bytes);
114 if (ret < 0)
115 return ret;
116 return 0;
117}
118
119static int write_device(struct i2c_client *i2c, int reg,
120 int bytes, void *src)
121{
122 unsigned char buf[2];
123 struct i2c_adapter *adap = i2c->adapter;
124 struct i2c_msg msg;
125 int ret;
126
127 buf[0] = (unsigned char)reg;
128 memcpy(&buf[1], src, bytes);
129 msg.addr = i2c->addr;
130 msg.flags = 0;
131 msg.len = bytes + 1;
132 msg.buf = buf;
133
134 ret = adap->algo->master_xfer(adap, &msg, 1);
135 if (ret < 0)
136 return ret;
137 return 0;
138}
139
140int pm860x_page_reg_write(struct i2c_client *i2c, int reg,
141 unsigned char data)
142{
143 unsigned char zero;
144 int ret;
145
146 i2c_lock_bus(adapter: i2c->adapter, I2C_LOCK_SEGMENT);
147 read_device(i2c, reg: 0xFA, bytes: 0, dest: &zero);
148 read_device(i2c, reg: 0xFB, bytes: 0, dest: &zero);
149 read_device(i2c, reg: 0xFF, bytes: 0, dest: &zero);
150 ret = write_device(i2c, reg, bytes: 1, src: &data);
151 read_device(i2c, reg: 0xFE, bytes: 0, dest: &zero);
152 read_device(i2c, reg: 0xFC, bytes: 0, dest: &zero);
153 i2c_unlock_bus(adapter: i2c->adapter, I2C_LOCK_SEGMENT);
154 return ret;
155}
156EXPORT_SYMBOL(pm860x_page_reg_write);
157
158int pm860x_page_bulk_read(struct i2c_client *i2c, int reg,
159 int count, unsigned char *buf)
160{
161 unsigned char zero = 0;
162 int ret;
163
164 i2c_lock_bus(adapter: i2c->adapter, I2C_LOCK_SEGMENT);
165 read_device(i2c, reg: 0xfa, bytes: 0, dest: &zero);
166 read_device(i2c, reg: 0xfb, bytes: 0, dest: &zero);
167 read_device(i2c, reg: 0xff, bytes: 0, dest: &zero);
168 ret = read_device(i2c, reg, bytes: count, dest: buf);
169 read_device(i2c, reg: 0xFE, bytes: 0, dest: &zero);
170 read_device(i2c, reg: 0xFC, bytes: 0, dest: &zero);
171 i2c_unlock_bus(adapter: i2c->adapter, I2C_LOCK_SEGMENT);
172 return ret;
173}
174EXPORT_SYMBOL(pm860x_page_bulk_read);
175

source code of linux/drivers/mfd/88pm860x-i2c.c