Patch "serial: 8250: Remove serial_rs485 sanitization from em485" has been added to the 5.10-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    serial: 8250: Remove serial_rs485 sanitization from em485

to the 5.10-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     serial-8250-remove-serial_rs485-sanitization-from-em.patch
and it can be found in the queue-5.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit a413188fb48c1a3020cdf83a17759dea71c29c00
Author: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
Date:   Mon Jun 6 13:04:33 2022 +0300

    serial: 8250: Remove serial_rs485 sanitization from em485
    
    [ Upstream commit 84f2faa7852e1f55d89bb0c99b3a672b87b11f87 ]
    
    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: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>
    Link: https://lore.kernel.org/r/20220606100433.13793-37-ilpo.jarvinen@xxxxxxxxxxxxxxx
    Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
    Stable-dep-of: 93810191f5d2 ("serial: 8250: omap: Fix missing PM runtime calls for omap8250_set_mctrl()")
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index f648fd1d7548..7cdfc2458d36 100644
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -661,13 +661,6 @@ 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);
 
@@ -675,15 +668,8 @@ 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;