drivers/media/pci/ddbridge/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
  19 void ddb_i2c_release(struct ddb *dev);
  20 int ddb_i2c_init(struct ddb *dev);
  21
  22 /******************************************************************************/
  23
  24 static 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
  35 static 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
  44 static 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
  52 static 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
  63 static 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
  75 static 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
  83 static 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
  91 static 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
  97 static 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__ */