USB-serial fixes for 5.6-rc2

Here's a fix for a ch341 regression in 5.5 which people have started to
 hit, and a fix for a logic error in an ir-usb error path.
 
 Both have been in linux-next with no reported issues.
 
 Signed-off-by: Johan Hovold <johan@kernel.org>
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Merge tag 'usb-serial-5.6-rc2' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial into usb-linus

Johan writes:

USB-serial fixes for 5.6-rc2

Here's a fix for a ch341 regression in 5.5 which people have started to
hit, and a fix for a logic error in an ir-usb error path.

Both have been in linux-next with no reported issues.

Signed-off-by: Johan Hovold <johan@kernel.org>

* tag 'usb-serial-5.6-rc2' of https://git.kernel.org/pub/scm/linux/kernel/git/johan/usb-serial:
  USB: serial: ch341: fix receiver regression
  USB: serial: ir-usb: Silence harmless uninitialized variable warning

drivers/usb/serial/ch341.c

@@ -205,6 +205,16 @@ static int ch341_get_divisor(speed_t speed)
 			16 * speed - 16 * CH341_CLKRATE / (clk_div * (div + 1)))
 		div++;
 
+	/*
+	 * Prefer lower base clock (fact = 0) if even divisor.
+	 *
+	 * Note that this makes the receiver more tolerant to errors.
+	 */
+	if (fact == 1 && div % 2 == 0) {
+		div /= 2;
+		fact = 0;
+	}
+
 	return (0x100 - div) << 8 | fact << 2 | ps;
 }
 

drivers/usb/serial/ir-usb.c

@@ -448,7 +448,7 @@ static void ir_set_termios(struct tty_struct *tty,
 			usb_sndbulkpipe(udev, port->bulk_out_endpointAddress),
 			transfer_buffer, 1, &actual_length, 5000);
 	if (ret || actual_length != 1) {
-		if (actual_length != 1)
+		if (!ret)
 			ret = -EIO;
 		dev_err(&port->dev, "failed to change line speed: %d\n", ret);
 	}