zephyr/drivers/i2c/i2c-priv.h
Peter Bigot 5f481bb042 drivers: rearrange for standard use of extern "C" in private headers
Consistently place C++ use of extern "C" after all include directives,
within the negative branch of _ASMLANGUAGE if used.

Only updated in headers that already had support for drivers built with
a C++ compiler.

The spi_dw.h file defines macros to declare functions, then uses them
within a file that may have out-of-tree overrides.  In this case we
leave the including file extern "C" active for backward compatibility.

Background from issue #17997:

Declarations that use C linkage should be placed within extern "C"
so the language linkage is correct when the header is included by
a C++ compiler.

Similarly #include directives should be outside the extern "C" to
ensure the language-specific default linkage is applied to any
declarations provided by the included header.

See: https://en.cppreference.com/w/cpp/language/language_linkage
Signed-off-by: Peter Bigot <peter.bigot@nordicsemi.no>
2019-08-13 18:00:31 +02:00

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C

/*
* Copyright (c) 2017 Linaro Limited
*
* SPDX-License-Identifier: Apache-2.0
*/
#ifndef ZEPHYR_DRIVERS_I2C_I2C_PRIV_H_
#define ZEPHYR_DRIVERS_I2C_I2C_PRIV_H_
#include <drivers/i2c.h>
#include <dt-bindings/i2c/i2c.h>
#include <logging/log.h>
#ifdef __cplusplus
extern "C" {
#endif
static inline u32_t i2c_map_dt_bitrate(u32_t bitrate)
{
switch (bitrate) {
case I2C_BITRATE_STANDARD:
return I2C_SPEED_STANDARD << I2C_SPEED_SHIFT;
case I2C_BITRATE_FAST:
return I2C_SPEED_FAST << I2C_SPEED_SHIFT;
case I2C_BITRATE_FAST_PLUS:
return I2C_SPEED_FAST_PLUS << I2C_SPEED_SHIFT;
case I2C_BITRATE_HIGH:
return I2C_SPEED_HIGH << I2C_SPEED_SHIFT;
case I2C_BITRATE_ULTRA:
return I2C_SPEED_ULTRA << I2C_SPEED_SHIFT;
}
LOG_ERR("Invalid I2C bit rate value");
return 0;
}
#ifdef __cplusplus
}
#endif
#endif /* ZEPHYR_DRIVERS_I2C_I2C_PRIV_H_ */