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From: Jingbao Qiu <qiujingbao.dlmu@gmail.com>
Date: Mon, 22 Jan 2024 16:34:00 +0800
Message-ID: <CAJRtX8QU8iHY1oQJ1uDN3YOmCeN7SH+vPC8nD29WS5+2DT1oKQ@mail.gmail.com>
Subject: Re: [PATCH v7 2/3] rtc: sophgo: add rtc support for Sophgo CV1800 SoC
To: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org, conor+dt@kernel.org, 
	chao.wei@sophgo.com, unicorn_wang@outlook.com, paul.walmsley@sifive.com, 
	palmer@dabbelt.com, aou@eecs.berkeley.edu, linux-rtc@vger.kernel.org, 
	devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, 
	linux-riscv@lists.infradead.org, dlan@gentoo.org
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On Mon, Jan 22, 2024 at 4:17=E2=80=AFPM Alexandre Belloni
<alexandre.belloni@bootlin.com> wrote:
>
> On 22/01/2024 16:06:30+0800, Jingbao Qiu wrote:
> > Implement the RTC driver for CV1800, which able to provide time alarm
> > and calibrate functionality.
> >
> > Signed-off-by: Jingbao Qiu <qiujingbao.dlmu@gmail.com>
> > ---
> >
> > Depends on https://lore.kernel.org/all/IA1PR20MB4953C774D41EDF1EADB6EC1=
8BB6D2@IA1PR20MB4953.namprd20.prod.outlook.com/
>
> What is the dependency?
>

Thank you, this driver requires support from the CLK driver.
I will add an explanation in the next version.

>
> Also, please fix the checkpatch.pl --strict warnings

I will use the -- strict option for testing.

>
> > +/**
> > + * cv1800_rtc_32k_coarse_val_calib() - Using an external
> > + * clock to coarse calibrate the crystal oscillator
> > + * @info: the device of calibrated
> > + *
> > + * @return 0 on success, or -1 on fail
> > + *
> > + * This RTC has an independent 32KHz oscillator. However,
> > + * the accuracy of this oscillator is easily affected by
> > + * external environmental interference,resulting in lower
> > + * accuracy than the internal oscillator.Therefore, a 25M
> > + * crystal oscillator is used as a reference source to
> > + * calibrate the RTC and improve its accuracy.Calibration
> > + * is completed through two steps, namely rough calibration
> > + * and fine calibration.
> > + */
> > +static int cv1800_rtc_32k_coarse_val_calib(struct cv1800_rtc_priv *inf=
o)
>
> This is still not working as well as you think it is. You should
> Implement the offset callbacks instead.
>
I'm sorry, I don't quite understand offset callbacks.
Do you mean that this function needs to be executed periodically.

Best regards,
Jingbao Qiu