On Wed, 2018-06-06 at 14:15 +0200, Giulio Benetti wrote: > Il 06/06/2018 13:56, Andy Shevchenko ha scritto: > > On Wed, 2018-06-06 at 11:49 +0200, Giulio Benetti wrote: > > > em485 gets lost during > > > > > > Copy em485 to final uart port. > > > > > > > Is it needed at all? > > > > The individual driver decides either to use software emulation (and > > calls explicitly serial8250_em485_init() for that) or do HW assisted > > stuff. > > In 8250_dw.c, during probe(), I need to call dw8250_rs485_config() > against local struct uart_8250_port uart = {}; > Inside serial8250_register_8250_port() not all uart fields are > copied(em485 too). > So after probe, em485 is NULL. > > Another way could be to call dw8250_rs485_config() against real uart > port, after calling serial8250_register_8250_port(), > would it make sense? Look at OMAP case closely. They have a callback to configure RS485 which is called in uart_set_rs485_config() which is called whenever user space does TIOCGRS485 IOCTL. So, it's completely driven by user space which makes sense by my opinion. -- Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> Intel Finland Oy -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html