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Message-ID: <1488abfa-9a0e-970b-e074-11842a6c6413@hust.edu.cn>
Date:   Wed, 26 Apr 2023 09:50:26 +0800
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Subject: Re: [PATCH] spi: davinci: Remove dead code in `davinci_spi_probe()`
To:     Mark Brown <broonie@kernel.org>
Cc:     Li Ningke <lnk_01@hust.edu.cn>,
        hust-os-kernel-patches@googlegroups.com, linux-spi@vger.kernel.org,
        linux-kernel@vger.kernel.org, Dan Carpenter <error27@gmail.com>
References: <20230423032446.34347-1-lnk_01@hust.edu.cn>
 <d29c4b3e-9e82-4ea9-9f0c-a8e2c7637eb9@sirena.org.uk>
 <46299274-d827-279f-cadf-020e93296c13@hust.edu.cn>
 <ed846afc-7155-4998-9a8d-e9d9e8aaf8e2@sirena.org.uk>
From:   Dongliang Mu <dzm91@hust.edu.cn>
In-Reply-To: <ed846afc-7155-4998-9a8d-e9d9e8aaf8e2@sirena.org.uk>
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On 2023/4/24 23:52, Mark Brown wrote:
> On Mon, Apr 24, 2023 at 08:03:42PM +0800, Dongliang Mu wrote:
>> On 2023/4/24 19:48, Mark Brown wrote:
>>> Is that check valid?  0 was a valid interrupt for some architectures...
>> We just follow the comments of platform_get_irq().
>>   * Gets an IRQ for a platform device and prints an error message if finding
>> the
>>   * IRQ fails. Device drivers should check the return value for errors so as
>> to
>>   * not pass a negative integer value to the request_irq() APIs.
> I'm not sure that's universally true yet, though there were some moves
> to try to get us there.  arm, where this driver is used, was one of the
> platforms with 0 as a valid interrupt.

Hi Brown,

First, we're sorry about the fact that our internal robot(beta) made a 
mistake and sent our testing message to LKML. We have fixed the 
incorrect logic.

Second, from code review of platform_get_irq / 
platform_get_irq_optional, it would warn IRQ 0 as an invalid IRQ number.

out:
	if (WARN(!ret, "0 is an invalid IRQ number\n"))
		return -EINVAL;
	return ret;

Dongliang Mu