[PATCH 4.4 34/64] usb: cdc-acm: Add DISABLE_ECHO for Renesas USB Download mode

From: Greg Kroah-Hartman
Date: Tue Nov 17 2020 - 08:09:11 EST


From: Chris Brandt <chris.brandt@xxxxxxxxxxx>

commit 6d853c9e4104b4fc8d55dc9cd3b99712aa347174 upstream.

Renesas R-Car and RZ/G SoCs have a firmware download mode over USB.
However, on reset a banner string is transmitted out which is not expected
to be echoed back and will corrupt the protocol.

Cc: stable <stable@xxxxxxxxxxxxxxx>
Acked-by: Oliver Neukum <oneukum@xxxxxxxx>
Signed-off-by: Chris Brandt <chris.brandt@xxxxxxxxxxx>
Link: https://lore.kernel.org/r/20201111131209.3977903-1-chris.brandt@xxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/usb/class/cdc-acm.c | 9 +++++++++
1 file changed, 9 insertions(+)

--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -1693,6 +1693,15 @@ static const struct usb_device_id acm_id
{ USB_DEVICE(0x0870, 0x0001), /* Metricom GS Modem */
.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
},
+ { USB_DEVICE(0x045b, 0x023c), /* Renesas USB Download mode */
+ .driver_info = DISABLE_ECHO, /* Don't echo banner */
+ },
+ { USB_DEVICE(0x045b, 0x0248), /* Renesas USB Download mode */
+ .driver_info = DISABLE_ECHO, /* Don't echo banner */
+ },
+ { USB_DEVICE(0x045b, 0x024D), /* Renesas USB Download mode */
+ .driver_info = DISABLE_ECHO, /* Don't echo banner */
+ },
{ USB_DEVICE(0x0e8d, 0x0003), /* FIREFLY, MediaTek Inc; andrey.arapov@xxxxxxxxx */
.driver_info = NO_UNION_NORMAL, /* has no union descriptor */
},