Commit 84f2faa7 authored by Ilpo Järvinen's avatar Ilpo Järvinen Committed by Greg Kroah-Hartman
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serial: 8250: Remove serial_rs485 sanitization from em485 



Serial core handles serial_rs485 sanitization.

When em485 init fails, there are two possible paths of entry:

  1) uart_rs485_config (init path) that fully clears port->rs485 on
     error.

  2) ioctl path with a pre-existing, valid port->rs485 unto which the
     kernel falls back on error and port->rs485 should therefore be
     kept untouched. The temporary rs485 struct is not returned to
     userspace in case of error so its flag don't matter.

...Thus SER_RS485_ENABLED clearing on error can/should be dropped.

Signed-off-by: default avatarIlpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220606100433.13793-37-ilpo.jarvinen@linux.intel.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent bbdcbc13

drivers/tty/serial/8250/8250_port.c

+2 −16
Original line number Diff line number Diff line
@@ -675,13 +675,6 @@ int serial8250_em485_config(struct uart_port *port, struct serial_rs485 *rs485) 
		rs485->flags &= ~SER_RS485_RTS_AFTER_SEND;

	}



	/* clamp the delays to [0, 100ms] */

	rs485->delay_rts_before_send = min(rs485->delay_rts_before_send, 100U);

	rs485->delay_rts_after_send  = min(rs485->delay_rts_after_send, 100U);



	memset(rs485->padding, 0, sizeof(rs485->padding));

	port->rs485 = *rs485;



	gpiod_set_value(port->rs485_term_gpio,

			rs485->flags & SER_RS485_TERMINATE_BUS);
@@ -689,15 +682,8 @@ int serial8250_em485_config(struct uart_port *port, struct serial_rs485 *rs485) 
	 * Both serial8250_em485_init() and serial8250_em485_destroy()

	 * are idempotent.

	 */

	if (rs485->flags & SER_RS485_ENABLED) {

		int ret = serial8250_em485_init(up);



		if (ret) {

			rs485->flags &= ~SER_RS485_ENABLED;

			port->rs485.flags &= ~SER_RS485_ENABLED;

		}

		return ret;

	}

	if (rs485->flags & SER_RS485_ENABLED)

		return serial8250_em485_init(up);



	serial8250_em485_destroy(up);

	return 0;