[PATCH 1/8] serial: core: only get RS485 termination gpio if supported

[Lino Sanfilippo]

On 23.06.22 at 18:32, Andy Shevchenko wrote:

>>
>> Ok I see the point. So what about changing it to:
>
> You mean adding below after the existing code in the module?

Right, to be more precise between getting the gpio and the error check:


	port->rs485_term_gpio = devm_gpiod_get_optional(dev, "rs485-term",
							GPIOD_OUT_LOW);

	if (port->rs485_term_gpio &&
	    !(port->rs485_supported->flags & SER_RS485_TERMINATE_BUS)) {
		dev_warn(port->dev,
			"%s (%d): RS485 termination gpio not supported by driver\n",
			port->name, port->line);
		devm_gpiod_put(dev, port->rs485_term_gpio);
		port->rs485_term_gpio = NULL;
	}

	if (IS_ERR(port->rs485_term_gpio)) {
		ret = PTR_ERR(port->rs485_term_gpio);
		port->rs485_term_gpio = NULL;
		return dev_err_probe(dev, ret, "Cannot get rs485-term-gpios\n");
	}

Regards,
Lino

>
>> 	if (port->rs485_term_gpio &&
>> 	    !(port->rs485_supported->flags & SER_RS485_TERMINATE_BUS)) {
>> 		dev_warn(port->dev,
>> 			"%s (%d): RS485 termination gpio not supported by driver\n",
>> 			port->name, port->line);
>> 		devm_gpiod_put(dev, port->rs485_term_gpio);
>> 		port->rs485_term_gpio = NULL;
>> 	}
>>
>> This would also be consistent to the warnings we print in uart_sanitize_serial_rs485() for invalid
>> RS485 settings.
>
> Probably it's okay, but I dunno we have much on this to gain. Users may start
> complaining of this (harmless) warning. I leave it to others to comment.
>