Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
MIME-Version: 1.0
References: <20221219212013.1294820-1-frank.jungclaus@esd.eu> <20221219212013.1294820-2-frank.jungclaus@esd.eu>
In-Reply-To: <20221219212013.1294820-2-frank.jungclaus@esd.eu>
From:   Vincent MAILHOL <mailhol.vincent@wanadoo.fr>
Date:   Tue, 20 Dec 2022 14:16:39 +0900
Message-ID: <CAMZ6RqKc0mvfQGEGb7gCE69Mskhzq5YKF88Jhe+1VR=43YW3Xg@mail.gmail.com>
Subject: Re: [PATCH 1/3] can: esd_usb: Improved behavior on esd CAN_ERROR_EXT
 event (1)
To:     Frank Jungclaus <frank.jungclaus@esd.eu>
Cc:     linux-can@vger.kernel.org, Marc Kleine-Budde <mkl@pengutronix.de>,
        Wolfgang Grandegger <wg@grandegger.com>,
        =?UTF-8?Q?Stefan_M=C3=A4tje?= <stefan.maetje@esd.eu>,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

On Tue. 20 Dec. 2022 at 06:25, Frank Jungclaus <frank.jungclaus@esd.eu> wrote:
>
> Moved the supply for cf->data[3] (bit stream position of CAN error)
> outside of the "switch (ecc & SJA1000_ECC_MASK){}"-statement, because
> this position is independent of the error type.
>
> Fixes: 96d8e90382dc ("can: Add driver for esd CAN-USB/2 device")
> Signed-off-by: Frank Jungclaus <frank.jungclaus@esd.eu>
> ---
>  drivers/net/can/usb/esd_usb.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/net/can/usb/esd_usb.c b/drivers/net/can/usb/esd_usb.c
> index 42323f5e6f3a..5e182fadd875 100644
> --- a/drivers/net/can/usb/esd_usb.c
> +++ b/drivers/net/can/usb/esd_usb.c
> @@ -286,7 +286,6 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
>                                 cf->data[2] |= CAN_ERR_PROT_STUFF;
>                                 break;
>                         default:
> -                               cf->data[3] = ecc & SJA1000_ECC_SEG;
>                                 break;
>                         }
>
> @@ -294,6 +293,9 @@ static void esd_usb_rx_event(struct esd_usb_net_priv *priv,
>                         if (!(ecc & SJA1000_ECC_DIR))
>                                 cf->data[2] |= CAN_ERR_PROT_TX;
>
> +                       /* Bit stream position in CAN frame as the error was detected */
> +                       cf->data[3] = ecc & SJA1000_ECC_SEG;

Can you confirm that the value returned by the device matches the
specifications from linux/can/error.h?

  https://elixir.bootlin.com/linux/latest/source/include/uapi/linux/can/error.h#L90

>                         if (priv->can.state == CAN_STATE_ERROR_WARNING ||
>                             priv->can.state == CAN_STATE_ERROR_PASSIVE) {
>                                 cf->data[1] = (txerr > rxerr) ?
> --
> 2.25.1
>