linux-can-fixes-for-6.1-20221124
can: mcba_usb: Fix termination command argument
Microchip USB Analyzer can activate the internal termination resistors
by setting the "termination" option ON, or OFF to to deactivate them.
As I've observed, both with my oscilloscope and captured USB packets
below, you must send "0" to turn it ON, and "1" to turn it OFF.
From the schematics in the user's guide, I can confirm that you must
drive the CAN_RES signal LOW "0" to activate the resistors.
Reverse the argument value of usb_msg.termination to fix this.
These are the two commands sequence, ON then OFF.
> No. Time Source Destination Protocol Length Info
> 1 0.000000 host 1.3.1 USB 46 URB_BULK out
>
> Frame 1: 46 bytes on wire (368 bits), 46 bytes captured (368 bits)
> USB URB
> Leftover Capture Data: a80000000000000000000000000000000000a8
>
> No. Time Source Destination Protocol Length Info
> 2 4.372547 host 1.3.1 USB 46 URB_BULK out
>
> Frame 2: 46 bytes on wire (368 bits), 46 bytes captured (368 bits)
> USB URB
> Leftover Capture Data: a80100000000000000000000000000000000a9
Signed-off-by: Yasushi SHOJI <yashi@spacecubics.com>
Link: https://lore.kernel.org/all/20221124152504.125994-1-yashi@spacecubics.com
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
1 file changed
