LXR linux/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 * This program is free software; you can redistribute it and/or
  10 * modify it under the terms of the GNU General Public License
  11 * version 2 only, as published by the Free Software Foundation.
  12 *
  13 * This program is distributed in the hope that it will be useful,
  14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 * GNU General Public License for more details.
  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
  28void ddb_i2c_release(struct ddb *dev);
  29int ddb_i2c_init(struct ddb *dev);
  30
  31/******************************************************************************/
  32
  33static 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
  44static 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
  53static 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
  61static 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
  72static 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
  84static 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
  92static 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
 100static 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
 106static 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