Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Subject: Re: [PATCH v2 1/1] can: ucan: add driver for Theobroma Systems UCAN
 devices
To:     Jakob Unterwurzacher <jakob.unterwurzacher@theobroma-systems.com>
Cc:     Martin Elshuber <martin.elshuber@theobroma-systems.com>,
        Philipp Tomsich <philipp.tomsich@theobroma-systems.com>,
        Marc Kleine-Budde <mkl@pengutronix.de>,
        linux-can@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20180313173520.21257-1-jakob.unterwurzacher@theobroma-systems.com>
 <20180313173520.21257-2-jakob.unterwurzacher@theobroma-systems.com>
 <d7986f8f-6c52-bf39-93f0-7a837bd85241@grandegger.com>
 <03024ab7-5386-3bcf-76f2-ef2e0e9e7a78@theobroma-systems.com>
From:   Wolfgang Grandegger <wg@grandegger.com>
Message-ID: <68564c40-396b-9081-8534-67fe96a6fb3f@grandegger.com>
Date:   Wed, 14 Mar 2018 10:17:40 +0100
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101
 Thunderbird/52.6.0
MIME-Version: 1.0
In-Reply-To: <03024ab7-5386-3bcf-76f2-ef2e0e9e7a78@theobroma-systems.com>
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Language: en-GB
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk


Am 14.03.2018 um 10:14 schrieb Jakob Unterwurzacher:
> On 14.03.18 10:11, Wolfgang Grandegger wrote:
>>> +    /* handle error frames */
>>> +    canid = le32_to_cpu(m->msg.can_msg.id);
>>> +    if (canid & CAN_ERR_FLAG) {
>>> +        ucan_handle_error_frame(up, m, canid);
>>> +        /* drop frame if berr-reporting is off */
>>> +        if (!(up->can.ctrlmode & CAN_CTRLMODE_BERR_REPORTING))
>>> +            return;
>>> +    }
>>
>> You still do not generate error messages for state changes, IIUC.
> 
> The hardware generates error frames on state changes - is that what you 
> mean?
> 
> In our testing, the state shows up (and updates) correctly in
> 
>      ip -details -statistics link show can0

Counting the state changes is one thing but you should also generate 
error messages for them.

Wolfgang.