From 8458e35443d30ec97ecc4b969eca77f2990d0d32 Mon Sep 17 00:00:00 2001
From: Johan Hovold <johan@kernel.org>
Date: Wed, 7 Apr 2021 12:39:08 +0200
Subject: [PATCH] USB: serial: mos7720: fix TIOCGSERIAL implementation
Git-commit: 8458e35443d30ec97ecc4b969eca77f2990d0d32
Patch-mainline: v5.13-rc1
References: git-fixes

TIOCSSERIAL is a horrid, underspecified, legacy interface which for most
serial devices is only useful for setting the close_delay and
closing_wait parameters.

The port parameter is used to set the I/O port and does not make any
sense to use for USB serial devices.

The xmit_fifo_size parameter could be used to set the hardware transmit
fifo size of a legacy UART when it could not be detected, but the
interface is limited to eight bits and should be left unset when not
used.

Similarly, baud_base could be used to set the UART base clock when it
could not be detected but might as well be left unset when it is not
known.

The close_delay and closing_wait parameters returned by TIOCGSERIAL are
specified in centiseconds (not jiffies). The driver does not yet support
changing these, but let's report back the default values actually used
(0.5 and 30 seconds, respectively).

Fixes: 0f64478cbc7a ("USB: add USB serial mos7720 driver")
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/usb/serial/mos7720.c | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/drivers/usb/serial/mos7720.c b/drivers/usb/serial/mos7720.c
index 701dfb32b129..7289d46c3164 100644
--- a/drivers/usb/serial/mos7720.c
+++ b/drivers/usb/serial/mos7720.c
@@ -1638,16 +1638,12 @@ static int get_serial_info(struct tty_struct *tty,
 			   struct serial_struct *ss)
 {
 	struct usb_serial_port *port = tty->driver_data;
-	struct moschip_port *mos7720_port = usb_get_serial_port_data(port);
 
 	ss->type		= PORT_16550A;
-	ss->line		= mos7720_port->port->minor;
-	ss->port		= mos7720_port->port->port_number;
-	ss->irq			= 0;
-	ss->xmit_fifo_size	= NUM_URBS * URB_TRANSFER_BUFFER_SIZE;
-	ss->baud_base		= 9600;
-	ss->close_delay		= 5*HZ;
-	ss->closing_wait	= 30*HZ;
+	ss->line		= port->minor;
+	ss->close_delay		= 50;
+	ss->closing_wait	= 3000;
+
 	return 0;
 }
 
-- 
2.26.2