drivers/media/pci/ddbridge/ddbridge-i2c.h

   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  = &reg, .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__ */