Unable to set the number of data bits on serial port in Uart::begin due to data type width

[TomKeddie]

These constants for the number of data bits are all 16 bit values.

#define HARDSER_DATA_5      (0x100ul)
#define HARDSER_DATA_6      (0x200ul)
#define HARDSER_DATA_7      (0x300ul)
#define HARDSER_DATA_8      (0x400ul)
#define HARDSER_DATA_MASK   (0xF00ul)`

But Uart::begin takes an 8 bit value
void begin(unsigned long baudrate, uint8_t config);

This makes it impossible to change the number of bits.

[keestux]

This problem is not fixed properly. Argument config was changed to uint16_t as shown below

void Uart::begin(unsigned long baudrate, uint16_t config)

however the other Uart::begin calls it with a cast to uint8_t

void Uart::begin(unsigned long baudrate)
{
  begin(baudrate, (uint8_t)SERIAL_8N1);
}

So far, nobody noticed, probably because nobody uses other than 8 data bits. In that case you won't notice the bug.
Wouldn't it be better to drop this latter function and to add a default value for config in the other begin()?