2ac04c11ac
This patch adds explicit overrides as this is now required when using "-Wall" with clang >= 3.5, the latter now part of the most recent XCode. The patch consequently removes "virtual" for those methods where "override" is added. The latter should be enough of an indication. As part of this patch, a few minor issues that clang >= 3.5 complains about are also resolved (unused methods and variables).
154 lines
4.6 KiB
C++
154 lines
4.6 KiB
C++
/*
|
|
* Copyright (c) 2012 ARM Limited
|
|
* All rights reserved
|
|
*
|
|
* The license below extends only to copyright in the software and shall
|
|
* not be construed as granting a license to any other intellectual
|
|
* property including but not limited to intellectual property relating
|
|
* to a hardware implementation of the functionality of the software
|
|
* licensed hereunder. You may use the software subject to the license
|
|
* terms below provided that you ensure that this notice is replicated
|
|
* unmodified and in its entirety in all distributions of the software,
|
|
* modified or unmodified, in source code or in binary form.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions are
|
|
* met: redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer;
|
|
* redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution;
|
|
* neither the name of the copyright holders nor the names of its
|
|
* contributors may be used to endorse or promote products derived from
|
|
* this software without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
|
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
|
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
|
|
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
|
|
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
|
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
|
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
|
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
|
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
|
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
*
|
|
* Authors: Peter Enns
|
|
*/
|
|
|
|
|
|
/** @file
|
|
* Implementiation of an i2c bus
|
|
*/
|
|
|
|
#ifndef __DEV_I2CBUS__
|
|
#define __DEV_I2CBUS__
|
|
|
|
#include <map>
|
|
|
|
#include "dev/i2cdev.hh"
|
|
#include "dev/io_device.hh"
|
|
#include "params/I2CBus.hh"
|
|
|
|
class I2CBus : public BasicPioDevice
|
|
{
|
|
protected:
|
|
|
|
enum I2CState {
|
|
IDLE,
|
|
RECEIVING_ADDR,
|
|
RECEIVING_DATA,
|
|
SENDING_DATA,
|
|
};
|
|
|
|
/**
|
|
* Read [and Set] serial control bits:
|
|
* Bit [0] is SCL
|
|
* Bit [1] is SDA
|
|
*
|
|
* http://infocenter.arm.com/help/topic/com.arm.doc.dui0440b/Bbajdjeg.html
|
|
*/
|
|
static const int SB_CONTROLS = 0x0;
|
|
/** Clear control bits. Analogous to SB_CONTROLS */
|
|
static const int SB_CONTROLC = 0x4;
|
|
|
|
/** I2C clock wire (0, 1). */
|
|
uint8_t scl;
|
|
/** I2C data wire (0, 1) */
|
|
uint8_t sda;
|
|
|
|
/**
|
|
* State used by I2CBus::write to determine what stage of an i2c
|
|
* transmission it is currently in.
|
|
*/
|
|
enum I2CState state;
|
|
|
|
/**
|
|
* Order of the bit of the current message that is being sent or
|
|
* received (0 - 7).
|
|
*/
|
|
int currBit;
|
|
|
|
/**
|
|
* Key used to access a device in the slave devices map. This
|
|
* is the same address that is specified in kernel board
|
|
* initialization code (e.g., arch/arm/mach-realview/core.c).
|
|
*/
|
|
uint8_t i2cAddr;
|
|
|
|
/** 8-bit buffer used to send and receive messages bit by bit. */
|
|
uint8_t message;
|
|
|
|
/**
|
|
* All the slave i2c devices that are connected to this
|
|
* bus. Each device has an address that points to the actual
|
|
* device.
|
|
*/
|
|
std::map<uint8_t, I2CDevice*> devices;
|
|
|
|
/**
|
|
* Update data (sda) and clock (scl) to match any transitions
|
|
* specified by pkt.
|
|
*
|
|
* @param pkt memory request packet
|
|
*/
|
|
void updateSignals(PacketPtr pkt);
|
|
|
|
/**
|
|
* Clock set check
|
|
*
|
|
* @param pkt memory request packet
|
|
* @return true if pkt indicates that scl transition from 0 to 1
|
|
*/
|
|
bool isClockSet(PacketPtr pkt) const;
|
|
|
|
/**
|
|
* i2c start signal check
|
|
*
|
|
* @param pkt memory request packet
|
|
* @return true if pkt indicates a new transmission
|
|
*/
|
|
bool isStart(PacketPtr pkt) const;
|
|
|
|
/**
|
|
* i2c end signal check
|
|
*
|
|
* @param pkt memory request packet
|
|
* @return true if pkt indicates stopping the current transmission
|
|
*/
|
|
bool isEnd(PacketPtr pkt) const;
|
|
|
|
public:
|
|
|
|
I2CBus(const I2CBusParams* p);
|
|
|
|
Tick read(PacketPtr pkt) override;
|
|
Tick write(PacketPtr pkt) override;
|
|
|
|
void serialize(CheckpointOut &cp) const override;
|
|
void unserialize(CheckpointIn &cp) override;
|
|
};
|
|
|
|
#endif //__DEV_I2CBUS
|