Merges https://github.com/espressif/esp-idf/pull/12093
fix(ll): remove FLAG_ATTR macro
Such kind of operator overload will not work because C++ thinks such overload is ambiguous and it still prefer the built-in one which accepts and returns integer. Manually force type conversion seems to be unavoidable.
1. Concurrency might cause ESP_ERR_TIMEOUT when calling uart_wait_tx_done
2. Concurrency might cause RTS line being de-assreted during tx transmission for rs485 mode
I'm including <hal/uart_ll.h> in my C++ application because I need to
bypass the uart driver. The inline functions in the header file fail to
compile as C++.
All of the enums need explicit casts for conversion to/from integers.
Merges https://github.com/espressif/esp-idf/pull/10106
XTAL_CLK_FREQ now depends on the actual XTAL used, remove this macro
and get the XTAL frequency from the RTC register instead.
No uses of XTAL_CLK_FREQ found, other than in the UART LL.
