Re: [PATCH 2/3] rtc: add rtc controller support for Sophgo CV1800B SoC

From: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
To: Jingbao Qiu <qiujingbao.dlmu@gmail.com>,
	a.zummo@towertech.it, alexandre.belloni@bootlin.com,
	krzysztof.kozlowski+dt@linaro.org, chao.wei@sophgo.com,
	unicorn_wang@outlook.com, conor+dt@kernel.org,
	robh+dt@kernel.org, conor@kernel.org, paul.walmsley@sifive.com,
	palmer@dabbelt.com, aou@eecs.berkeley.edu
Cc: linux-rtc@vger.kernel.org, devicetree@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/3] rtc: add rtc controller support for Sophgo CV1800B SoC
Date: Tue, 21 Nov 2023 11:01:54 +0100	[thread overview]
Message-ID: <09b29f1f-a42b-49f7-afca-f82357acd4c8@linaro.org> (raw)
In-Reply-To: <20231121094642.2973795-3-qiujingbao.dlmu@gmail.com>

On 21/11/2023 10:46, Jingbao Qiu wrote:
> Implement the RTC driver for CV1800B, which able to provide time and
> alarm functionality.
> 
> Signed-off-by: Jingbao Qiu <qiujingbao.dlmu@gmail.com>
> ---
>  drivers/rtc/Kconfig       |  10 ++
>  drivers/rtc/Makefile      |   1 +
>  drivers/rtc/rtc-cv1800b.c | 293 ++++++++++++++++++++++++++++++++++++++
>  3 files changed, 304 insertions(+)
>  create mode 100644 drivers/rtc/rtc-cv1800b.c

Bindings were not tested, so I assume you did not compile the code
either. Please confirm that you fixed all warnings pointed out by W=1
builds, smatch and sparse. All of them.

> 
> diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
> index 3814e0845e77..2089cceea38c 100644
> --- a/drivers/rtc/Kconfig
> +++ b/drivers/rtc/Kconfig
> @@ -1103,6 +1103,16 @@ config RTC_DRV_DS2404
>  	  This driver can also be built as a module. If so, the module
>  	  will be called rtc-ds2404.
>  
> +config RTC_DRV_CV1800B
> +	tristate "Sophgo CV1800B RTC"
> +	depends on ARCH_SOPHGO || COMPILE_TEST
> +	help
> +	  If you say yes here you will get support for the
> +	  RTC of the Sophgo CV1800B SOC.
> +
> +	  This depend on ARCH_SOPHGO and COMPILE_TEST. Please
> +	  first config that.

...

> +static int cv1800b_rtc_probe(struct platform_device *pdev)
> +{
> +	struct cv1800b_rtc_priv *rtc;
> +	struct resource *res;
> +	int ret;
> +
> +	rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
> +	if (!rtc)
> +		return -ENOMEM;
> +
> +	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	if (!res) {
> +		ret = -ENODEV;
> +		goto err;
> +	}
> +
> +	rtc->core_map = devm_ioremap_resource(&pdev->dev, res);

Use helper combining these two calls.

> +	if (IS_ERR(rtc->core_map)) {
> +		ret = PTR_ERR(rtc->core_map);
> +		goto err;
> +	}
> +
> +	rtc->irq = platform_get_irq(pdev, 0);
> +	platform_set_drvdata(pdev, rtc);

Your code has random order. First you get IRQ, then you check its value,
then you go further.

> +	if (rtc->irq < 0) {
> +		ret = -EINVAL;
> +		goto err;
> +	}
> +
> +	ret =
> +	    devm_request_irq(&pdev->dev, rtc->irq, cv1800b_rtc_irq_handler,

Wrong wrapping.

> +			     IRQF_SHARED, "rtc alarm", &pdev->dev);

Why shared?

> +	if (ret)
> +		goto err;
> +
> +	rtc->clk = devm_clk_get(&pdev->dev, NULL);
> +	if (IS_ERR(rtc->clk)) {
> +		dev_err(&pdev->dev, "no clock");

This code is not ready for upstream. There are multiple things wrong here.

First, syntax is return dev_err_probe.

Second, you do not have clocks and you do not allow them! Just open your
binding.

Third, use wrapper - devm_clk_get_enable or something like that.

> +		ret = PTR_ERR(rtc->clk);
> +		goto err;
> +	}

Blank line.

> +	ret = clk_prepare_enable(rtc->clk);
> +	if (ret)
> +		goto err;

Blank line.

> +	ret = cv1800b_rtc_softinit(rtc);
> +	if (ret)
> +		goto err;
> +	cv1800b_rtc_alarm_irq_enable(&pdev->dev, 1);
> +	rtc->rtc_dev = devm_rtc_allocate_device(&pdev->dev);
> +	if (IS_ERR(rtc->rtc_dev)) {
> +		ret = PTR_ERR(rtc->rtc_dev);
> +		goto err;
> +	}
> +	rtc->rtc_dev->range_max = U32_MAX;
> +	rtc->rtc_dev->ops = &cv800b_rtc_ops;
> +
> +	return rtc_register_device(rtc->rtc_dev);
> +err:
> +	return dev_err_probe(&pdev->dev, ret, "Failed to init cv1800b rtc\n");

Drop, just return.

Best regards,
Krzysztof