On 10. 05. 21, 11:47, Johan Hovold wrote:
--- a/drivers/tty/tty_ioctl.c +++ b/drivers/tty/tty_ioctl.c @@ -300,6 +300,48 @@ int tty_termios_hw_change(const struct ktermios *a, const struct ktermios *b)
...
+unsigned char tty_get_byte_size(unsigned int cflag, bool account_flags) +{ + unsigned char bits; + + switch (cflag & CSIZE) { + case CS5: + bits = 5; + break; + case CS6: + bits = 6; + break; + case CS7: + bits = 7; + break; + case CS8: + default: + bits = 8; + break; + } + + if (!account_flags) + return bits; + + if (cflag & CSTOPB) + bits++; + if (cflag & PARENB) + bits++; + + return bits + 2; +} +EXPORT_SYMBOL_GPL(tty_get_byte_size);This should really be two functions rather than passing a bool argument. I think naming them tty_get_word_size() and tty_get_frame_size() would be much more clear than than "byte size" + flag.
Maybe I am screwed, but word means exactly 2B here. So instead, I would go for:
s/word/char/ -- might be confused with C's char, 1B, or maybe not -- or s/word/data/ -- more generic and generally used in serial terminology.
I realise that the serial-driver interface only uses a cflag argument, but I think we should consider passing a pointer to the termios structure instead.
That's impossible as termios is not always at hand. Examples are: pch_uart_startup -> uart_update_timeout sunsab_console_setup -> sunsab_convert_to_sab -> uart_update_timeout sunsu_kbd_ms_init -> sunsu_change_speed -> uart_update_timeout Let me document that in the commit. thanks, -- js suse labs
