Re: [PATCH] can: mcba_usb: Fix termination command argument

[Marc Kleine-Budde <mkl@pengutronix.de>]

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Let's take the original driver author into the loop.

On 24.11.2022 04:44:06, Yasushi SHOJI wrote:
> Microchip USB Analyzer can be set with termination setting ON or OFF.
> As I've observed, both with my oscilloscope and USB packet capture
> below, you must send "0" to turn it ON, and "1" to turn it OFF.
> 
> Reverse the argument value 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

Is this the USB data after applying the patch?

Can you measure the resistance between CAN-H and CAN-L to verify that
your patch fixes the problem?

> Signed-off-by: Yasushi SHOJI <yashi@spacecubics.com>
> ---
>  drivers/net/can/usb/mcba_usb.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/net/can/usb/mcba_usb.c b/drivers/net/can/usb/mcba_usb.c
> index 218b098b261d..67beff1a3876 100644
> --- a/drivers/net/can/usb/mcba_usb.c
> +++ b/drivers/net/can/usb/mcba_usb.c
> @@ -785,9 +785,9 @@ static int mcba_set_termination(struct net_device *netdev, u16 term)
>  	};
>  
>  	if (term == MCBA_TERMINATION_ENABLED)
> -		usb_msg.termination = 1;
> -	else
>  		usb_msg.termination = 0;
> +	else
> +		usb_msg.termination = 1;
>  
>  	mcba_usb_xmit_cmd(priv, (struct mcba_usb_msg *)&usb_msg);

What about the static void mcba_usb_process_ka_usb() function? Do you
need to convert this, too?

Marc

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