Subject: Re: [PATCH v3 2/2] clocksource: sprd: Add timer driver for Spreadtrum
 SC9860 platform
To: Baolin Wang <baolin.wang@linaro.org>
Cc: Baolin Wang <baolin.wang@spreadtrum.com>,
        Thomas Gleixner <tglx@linutronix.de>, Rob Herring <robh+dt@kernel.org>,
        Mark Rutland <mark.rutland@arm.com>, DTML <devicetree@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>, Mark Brown <broonie@kernel.org>,
        Chunyan Zhang <zhang.chunyan@linaro.org>
References: <1b80566bd849d68b0fc8de54ecbbc7b4efbb1077.1512708743.git.baolin.wang@spreadtrum.com>
 <c85f55a434efada592c50f46c0d0532fdb5340b0.1512708743.git.baolin.wang@spreadtrum.com>
 <05f19500-f8a3-7afc-a8d9-bcf0aff3e6bc@linaro.org>
 <CAMz4ku+10jTXe4bykByO_iLM33ACTu9jSnrX=i66MD3F79w9dQ@mail.gmail.com>
 <3c1da7bb-a380-072f-957d-221a6f177217@linaro.org>
 <CAMz4kuLQyD5=X7PEOX98_drt66yc=Fq+KxMFHDW6tp_yZsxtsQ@mail.gmail.com>
 <CAMz4ku+4F6dLSrt=D9mt7=aaQu1G=deiK50YhBDnTN2jKtFGrA@mail.gmail.com>
From: Daniel Lezcano <daniel.lezcano@linaro.org>
Message-ID: <f1deccee-66d6-632f-9153-fb4b3c6bf60f@linaro.org>
Date: Tue, 12 Dec 2017 10:43:40 +0100
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On 12/12/2017 10:41, Baolin Wang wrote:
> Hi Daniel,
> 
> On 12 December 2017 at 17:26, Baolin Wang <baolin.wang@linaro.org> wrote:
>> Hi Daniel,
>>
>> On 12 December 2017 at 17:16, Daniel Lezcano <daniel.lezcano@linaro.org> wrote:
>>>
>>> Hi Baolin,
>>>
>>>
>>> On 08/12/2017 09:20, Baolin Wang wrote:
>>>
>>> [ ... ]
>>>
>>>>>> +static irqreturn_t sprd_timer_interrupt(int irq, void *dev_id)
>>>>>> +{
>>>>>> +     struct clock_event_device *ce = (struct clock_event_device *)dev_id;
>>>>>> +     struct timer_of *to = to_timer_of(ce);
>>>>>> +
>>>>>> +     sprd_timer_clear_interrupt(timer_of_base(to));
>>>>>> +
>>>>>> +     if (clockevent_state_oneshot(ce))
>>>>>> +             sprd_timer_disable(timer_of_base(to));
>>>>>> +
>>>>>> +     ce->event_handler(ce);
>>>>>> +     return IRQ_HANDLED;
>>>>>> +}
>>>>>> +
>>>>>> +static struct timer_of to = {
>>>>>> +     .flags = TIMER_OF_IRQ | TIMER_OF_BASE,
>>>>>
>>>>> Why not the TIMER_OF_CLOCK ?
>>>>
>>>> The timer's clock is fixed to 32.768K and no need to divide the
>>>> frequency, so our clock tree does not supply the timer's clock now.
>>>
>>> The driver is fine. However, I would like to unify the clk usage in the
>>> timer driver, so if you refer to a clock so the TIMER_OF_CLOCK can be
>>> used, that will nice.
>>
>> I understand your concern, but I've asked our clock driver owner in
>> Spreadtrum, we have no related registers to describe the topology of
>> the RTC fixed 32.768K, so the clock driver can not add timer's clock
>> node.
> 
> Sorry for my misunderstanding, I confirmed with Chunyan (who
> upstreamed our clock driver), she told me that we can get the clock
> rate from clock node. I will fix this issue in next version. Thanks
> for your comments.

Great, thanks Baolin.


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