From a2982a9e346263dd35644f7f61f6e4bcd96b7ab7 Mon Sep 17 00:00:00 2001 From: Nicolas Schodet Date: Wed, 20 Feb 2013 00:37:08 +0100 Subject: digital/ucoolib/ucoolib/hal/i2c: add i2c driver --- digital/ucoolib/ucoolib/intf/i2c.hh | 121 ++++++++++++++++++++++++++++++++++++ 1 file changed, 121 insertions(+) create mode 100644 digital/ucoolib/ucoolib/intf/i2c.hh (limited to 'digital/ucoolib/ucoolib/intf') diff --git a/digital/ucoolib/ucoolib/intf/i2c.hh b/digital/ucoolib/ucoolib/intf/i2c.hh new file mode 100644 index 00000000..622510a1 --- /dev/null +++ b/digital/ucoolib/ucoolib/intf/i2c.hh @@ -0,0 +1,121 @@ +#ifndef ucoolib_intf_i2c_hh +#define ucoolib_intf_i2c_hh +// ucoolib - Microcontroller object oriented library. {{{ +// +// Copyright (C) 2013 Nicolas Schodet +// +// APBTeam: +// Web: http://apbteam.org/ +// Email: team AT apbteam DOT org +// +// This program is free software; you can redistribute it and/or modify +// it under the terms of the GNU General Public License as published by +// the Free Software Foundation; either version 2 of the License, or +// (at your option) any later version. +// +// This program is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU General Public License for more details. +// +// You should have received a copy of the GNU General Public License +// along with this program; if not, write to the Free Software +// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. +// +// }}} +#include "ucoolib/common.hh" + +namespace ucoo { + +/// Master side of I2C interface. +class I2cMaster +{ + public: + /// Master transfer status, any other value is the transfer size in case + /// of success. + enum Status + { + /// Transfer is still ongoing. + STATUS_BUSY = -1, + /// Transfer finished with error. + STATUS_ERROR = 0, + }; + /// Callback used when master transfer is finised. + class FinishedHandler + { + public: + /// Called when transfer is finished, may be called in interrupt + /// context. I2C send and recv can be called from this handler. + virtual void finished (int status) = 0; + }; + public: + /// Send data to selected slave. This is asynchronous, you will have to + /// poll status or use a callback to determine if transfer is finished. + /// Input buffer is not copied and should be kept valid until transfer is + /// finished. + /// + /// If asynchronous transfer is not supported, this will block. + virtual void send (uint8_t addr, const char *buf, int count) = 0; + /// Receive data from selected slave. This is asynchronous, you will have + /// to poll status or use a callback to determine if transfer is finished. + /// Buffer is directly written and should be kept valid until transfer is + /// finished. + /// + /// If asynchronous transfer is not supported, this will block. + virtual void recv (uint8_t addr, char *buf, int count) = 0; + /// Return last transfer status. + virtual int status () = 0; + /// Wait until transfer is finished and return status. + virtual int wait () = 0; + /// Register a handler called when transfer is finished. + void register_finished (FinishedHandler &finished_handler) + { finished_handler_ = &finished_handler; } + protected: + /// Default constructor. + I2cMaster () : finished_handler_ (0) { } + protected: + /// Handler called when transfer is finished. + FinishedHandler *finished_handler_; +}; + +/// Slave side of I2C interface. +class I2cSlave +{ + public: + /// Data source and sink. + /// + /// When master requests data from a slave or send data to it, slave is + /// expected to reply as quickly as possible as the bus is stalled until a + /// response is done. + /// + /// This interface provides data to send to master and receives data from + /// master. It has to be fast and may be run under an interrupt context. + class DataHandler + { + public: + /// Request data to send to master, should write to provided buffer of + /// size COUNT and return the writen size. + virtual int to_send (char *buf, int count) = 0; + /// Provide data sent by master, should make a copy if needed as data will + /// be discarded. + virtual void to_recv (const char *buf, int count) = 0; + }; + public: + /// Register data source and sink, along with 7 bit address (in MSB). + virtual void register_data (uint8_t addr, DataHandler &data_handler) = 0; + protected: + /// Default constructor. + I2cSlave () { } +}; + +/// Both side of I2C interface. +class I2c : public I2cMaster, public I2cSlave +{ + protected: + /// Default constructor. + I2c () { } +}; + +} // namespace ucoo + +#endif // ucoolib_intf_i2c_hh -- cgit v1.2.3