From: Hannu Hartikainen <hannu@xxxxxxx> commit 4897807753e078655a78de39ed76044d784f3e63 upstream. The device (32a7:0000 Heimann Sensor GmbH USB appset demo) claims to be a CDC-ACM device in its descriptors but in fact is not. If it is run with echo disabled it returns garbled data, probably due to something that happens in the TTY layer. And when run with echo enabled (the default), it will mess up the calibration data of the sensor the first time any data is sent to the device. In short, I had a bad time after connecting the sensor and trying to get it to work. I hope blacklisting it in the cdc-acm driver will save someone else a bit of trouble. Signed-off-by: Hannu Hartikainen <hannu@xxxxxxx> Cc: stable <stable@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20210622141454.337948-1-hannu@xxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/usb/class/cdc-acm.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -1959,6 +1959,11 @@ static const struct usb_device_id acm_id .driver_info = IGNORE_DEVICE, }, + /* Exclude Heimann Sensor GmbH USB appset demo */ + { USB_DEVICE(0x32a7, 0x0000), + .driver_info = IGNORE_DEVICE, + }, + /* control interfaces without any protocol set */ { USB_INTERFACE_INFO(USB_CLASS_COMM, USB_CDC_SUBCLASS_ACM, USB_CDC_PROTO_NONE) },