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Diffstat (limited to 'src/drivers/device/i2c_linux.h')
-rw-r--r-- | src/drivers/device/i2c_linux.h | 152 |
1 files changed, 152 insertions, 0 deletions
diff --git a/src/drivers/device/i2c_linux.h b/src/drivers/device/i2c_linux.h new file mode 100644 index 000000000..3de6c9658 --- /dev/null +++ b/src/drivers/device/i2c_linux.h @@ -0,0 +1,152 @@ +/**************************************************************************** + * + * Copyright (C) 2012 PX4 Development Team. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. 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. + * 3. Neither the name PX4 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. + * + ****************************************************************************/ + +/** + * @file i2c.h + * + * Base class for devices connected via I2C. + */ + +#ifndef _DEVICE_I2C_H +#define _DEVICE_I2C_H + +#include "device.h" + +#include <px4_i2c.h> + +namespace device __EXPORT +{ + +/** + * Abstract class for character device on I2C + */ +class __EXPORT I2C : public CDev +{ + +public: + + /** + * Get the address + */ + int16_t get_address() const { return _address; } + + static int set_bus_clock(unsigned bus, unsigned clock_hz); + + static unsigned int _bus_clocks[3]; + +protected: + /** + * The number of times a read or write operation will be retried on + * error. + */ + unsigned _retries; + + /** + * The I2C bus number the device is attached to. + */ + int _bus; + + /** + * @ Constructor + * + * @param name Driver name + * @param devname Device node name + * @param bus I2C bus on which the device lives + * @param address I2C bus address, or zero if set_address will be used + * @param frequency I2C bus frequency for the device (currently not used) + * @param irq Interrupt assigned to the device (or zero if none) + */ + I2C(const char *name, + const char *devname, + int bus, + uint16_t address, + uint32_t frequency); + virtual ~I2C(); + + virtual int init(); + + /** + * Check for the presence of the device on the bus. + */ + virtual int probe(); + + /** + * Perform an I2C transaction to the device. + * + * At least one of send_len and recv_len must be non-zero. + * + * @param send Pointer to bytes to send. + * @param send_len Number of bytes to send. + * @param recv Pointer to buffer for bytes received. + * @param recv_len Number of bytes to receive. + * @return OK if the transfer was successful, -errno + * otherwise. + */ + int transfer(const uint8_t *send, unsigned send_len, + uint8_t *recv, unsigned recv_len); + + /** + * Perform a multi-part I2C transaction to the device. + * + * @param msgv An I2C message vector. + * @param msgs The number of entries in the message vector. + * @return OK if the transfer was successful, -errno + * otherwise. + */ + int transfer(px4_i2c_msg_t *msgv, unsigned msgs); + + /** + * Change the bus address. + * + * Most often useful during probe() when the driver is testing + * several possible bus addresses. + * + * @param address The new bus address to set. + */ + void set_address(uint16_t address) { + _address = address; + _device_id.devid_s.address = _address; + } + +private: + uint16_t _address; + uint32_t _frequency; + px4_i2c_dev_t *_dev; + + I2C(const device::I2C&); + I2C operator=(const device::I2C&); +}; + +} // namespace device + +#endif /* _DEVICE_I2C_H */ |