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Date:   Fri, 18 Mar 2022 07:09:32 -0700
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Subject: Re: [PATCH v2] i2c: add tracepoints for I2C slave events
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To:     Wolfram Sang <wsa@kernel.org>,
        Steven Rostedt <rostedt@goodmis.org>,
        "Ingo Molnar" <mingo@redhat.com>,
        Jamie Iles <quic_jiles@quicinc.com>,
        "Graeme Gregory" <quic_ggregory@quicinc.com>,
        <linux-kernel@vger.kernel.org>, <linux-i2c@vger.kernel.org>
References: <20220308163333.3985974-1-quic_jaehyoo@quicinc.com>
 <YjRkvPc9uahbozbQ@shikoro>
From:   Jae Hyun Yoo <quic_jaehyoo@quicinc.com>
In-Reply-To: <YjRkvPc9uahbozbQ@shikoro>
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Hi Wolfram,

On 3/18/2022 3:53 AM, Wolfram Sang wrote:
>> +	if (trace_i2c_slave_enabled() && !ret)
>> +		trace_i2c_slave(client, event, val);
> 
> Why '!ret'? I think we should always print 'ret' in the trace as well.
> Backends are allowed to send errnos on WRITE_RECEIVED to NACK the
> reception of a byte. This is useful information, too, or?

Ah, you are right. As itself should trace all events including NACK
cases, it'd be better to print out the 'ret' too. I'll add it to v3.

Thanks,
Jae