diff mbox series

cdc-acm: Add DISABLE_ECHO quirk for Microchip/SMSC chip

Message ID 20200605105418.22263-1-joakim.tjernlund@infinera.com
State New
Headers show
Series cdc-acm: Add DISABLE_ECHO quirk for Microchip/SMSC chip | expand

Commit Message

Joakim Tjernlund June 5, 2020, 10:54 a.m. UTC
USB_DEVICE(0x0424, 0x274e) can send data before cdc_acm is ready,
causing garbage chars on the TTY causing stray input to the shell
and/or login prompt.

Signed-off-by: Joakim Tjernlund <joakim.tjernlund@infinera.com>
Cc: stable@vger.kernel.org
---
 drivers/usb/class/cdc-acm.c | 2 ++
 1 file changed, 2 insertions(+)
diff mbox series

Patch

diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index ded8d93834ca..d579b05a2c2b 100644
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -1689,6 +1689,8 @@  static int acm_pre_reset(struct usb_interface *intf)
 
 static const struct usb_device_id acm_ids[] = {
 	/* quirky and broken devices */
+	{ USB_DEVICE(0x0424, 0x274e), /* Microchip Technology, Inc. (formerly SMSC) */
+	  .driver_info = DISABLE_ECHO, }, /* DISABLE ECHO in termios flag */
 	{ USB_DEVICE(0x076d, 0x0006), /* Denso Cradle CU-321 */
 	.driver_info = NO_UNION_NORMAL, },/* has no union descriptor */
 	{ USB_DEVICE(0x17ef, 0x7000), /* Lenovo USB modem */