Received-SPF: pass (google.com: domain of linux-kernel+bounces-3435-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.48.161 as permitted sender) client-ip=147.75.48.161;
Date: Mon, 18 Dec 2023 13:33:05 +0200
From: Andy Shevchenko <andy@kernel.org>
To: xiongxin <xiongxin@kylinos.cn>
Cc: fancer.lancer@gmail.com, hoan@os.amperecomputing.com,
	linus.walleij@linaro.org, brgl@bgdev.pl, linux-gpio@vger.kernel.org,
	linux-kernel@vger.kernel.org, Riwen Lu <luriwen@kylinos.cn>
Subject: Re: [v2] gpio: dwapb: mask/unmask IRQ when disable/enale it
Message-ID: <ZYAt8Zlv9XMYO5FF@smile.fi.intel.com>
References: <20231218081246.1921152-1-xiongxin@kylinos.cn>
Precedence: bulk
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20231218081246.1921152-1-xiongxin@kylinos.cn>
Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo

On Mon, Dec 18, 2023 at 04:12:46PM +0800, xiongxin wrote:
> In the hardware implementation of the i2c hid driver based on dwapb gpio
> irq, when the user continues to use the i2c hid device in the suspend
> process, the i2c hid interrupt will be masked after the resume process
> is finished.
> 
> This is because the disable_irq()/enable_irq() of the dwapb gpio driver
> does not synchronize the irq mask register state. In normal use of the
> i2c hid procedure, the gpio irq irq_mask()/irq_unmask() functions are
> called in pairs. In case of an exception, i2c_hid_core_suspend() calls
> disable_irq() to disable the gpio irq. With low probability, this causes
> irq_unmask() to not be called, which causes the gpio irq to be masked
> and not unmasked in enable_irq(), raising an exception.
> 
> Add synchronization to the masked register state in the
> dwapb_irq_enable()/dwapb_irq_disable() function. mask the gpio irq
> before disabling it. After enabling the gpio irq, unmask the irq.

> Fixes: 7779b3455697 ("gpio: add a driver for the Synopsys DesignWare APB GPIO block")
> Signed-off-by: xiongxin <xiongxin@kylinos.cn>

Your SoB should go last.

> Signed-off-by: Riwen Lu <luriwen@kylinos.cn>

Then at all means what this SoB for? Either it's missing Co-developed-by,
or simply wrong.

> Tested-by: xiongxin <xiongxin@kylinos.cn>

This is assumed to be done by the contributor, but it's harmless to have it.

With the above being sorted out,
Reviewed-by: Andy Shevchenko <andy@kernel.org>

...

To Serge, I give my vote to hwirq as it is aligned with the documentation.

-- 
With Best Regards,
Andy Shevchenko