1 /* 2 * ddbridge-i2c.c: Digital Devices bridge i2c driver 3 * 4 * Copyright (C) 2010-2017 Digital Devices GmbH 5 * Ralph Metzler <rjkm@metzlerbros.de> 6 * Marcus Metzler <mocm@metzlerbros.de> 7 * 8 * This program is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU General Public License 10 * version 2 only, as published by the Free Software Foundation. 11 * 12 * This program is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 * 17 */ 18 19 #ifndef __DDBRIDGE_I2C_H__ 20 #define __DDBRIDGE_I2C_H__ 21 22 #include <linux/i2c.h> 23 24 #include "ddbridge.h" 25 26 /******************************************************************************/ 27 28 void ddb_i2c_release(struct ddb *dev); 29 int ddb_i2c_init(struct ddb *dev); 30 31 /******************************************************************************/ 32 33 static int __maybe_unused i2c_io(struct i2c_adapter *adapter, u8 adr, 34 u8 *wbuf, u32 wlen, u8 *rbuf, u32 rlen) 35 { 36 struct i2c_msg msgs[2] = { { .addr = adr, .flags = 0, 37 .buf = wbuf, .len = wlen }, 38 { .addr = adr, .flags = I2C_M_RD, 39 .buf = rbuf, .len = rlen } }; 40 41 return (i2c_transfer(adapter, msgs, 2) == 2) ? 0 : -1; 42 } 43 44 static int __maybe_unused i2c_write(struct i2c_adapter *adap, u8 adr, 45 u8 *data, int len) 46 { 47 struct i2c_msg msg = { .addr = adr, .flags = 0, 48 .buf = data, .len = len }; 49 50 return (i2c_transfer(adap, &msg, 1) == 1) ? 0 : -1; 51 } 52 53 static int __maybe_unused i2c_read(struct i2c_adapter *adapter, u8 adr, u8 *val) 54 { 55 struct i2c_msg msgs[1] = { { .addr = adr, .flags = I2C_M_RD, 56 .buf = val, .len = 1 } }; 57 58 return (i2c_transfer(adapter, msgs, 1) == 1) ? 0 : -1; 59 } 60 61 static int __maybe_unused i2c_read_regs(struct i2c_adapter *adapter, 62 u8 adr, u8 reg, u8 *val, u8 len) 63 { 64 struct i2c_msg msgs[2] = { { .addr = adr, .flags = 0, 65 .buf = ®, .len = 1 }, 66 { .addr = adr, .flags = I2C_M_RD, 67 .buf = val, .len = len } }; 68 69 return (i2c_transfer(adapter, msgs, 2) == 2) ? 0 : -1; 70 } 71 72 static int __maybe_unused i2c_read_regs16(struct i2c_adapter *adapter, 73 u8 adr, u16 reg, u8 *val, u8 len) 74 { 75 u8 msg[2] = { reg >> 8, reg & 0xff }; 76 struct i2c_msg msgs[2] = { { .addr = adr, .flags = 0, 77 .buf = msg, .len = 2 }, 78 { .addr = adr, .flags = I2C_M_RD, 79 .buf = val, .len = len } }; 80 81 return (i2c_transfer(adapter, msgs, 2) == 2) ? 0 : -1; 82 } 83 84 static int __maybe_unused i2c_write_reg16(struct i2c_adapter *adap, 85 u8 adr, u16 reg, u8 val) 86 { 87 u8 msg[3] = { reg >> 8, reg & 0xff, val }; 88 89 return i2c_write(adap, adr, msg, 3); 90 } 91 92 static int __maybe_unused i2c_write_reg(struct i2c_adapter *adap, 93 u8 adr, u8 reg, u8 val) 94 { 95 u8 msg[2] = { reg, val }; 96 97 return i2c_write(adap, adr, msg, 2); 98 } 99 100 static int __maybe_unused i2c_read_reg16(struct i2c_adapter *adapter, 101 u8 adr, u16 reg, u8 *val) 102 { 103 return i2c_read_regs16(adapter, adr, reg, val, 1); 104 } 105 106 static int __maybe_unused i2c_read_reg(struct i2c_adapter *adapter, 107 u8 adr, u8 reg, u8 *val) 108 { 109 return i2c_read_regs(adapter, adr, reg, val, 1); 110 } 111 112 #endif /* __DDBRIDGE_I2C_H__ */ 113