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Subject: Re: [PATCH v3] serial: port: Don't suspend if the port is still busy
To: Andy Shevchenko <andriy.shevchenko@linux.intel.com>, Jiri Slaby
	<jirislaby@kernel.org>
References: <20240208075216.48915-1-yangyicong@huawei.com>
 <beb599e2-ebc5-4b26-82c3-908830effd5a@kernel.org>
 <ZcUOp60BX8njHQ4Q@smile.fi.intel.com>
From: Yicong Yang <yangyicong@huawei.com>
Message-ID: <d6384122-08da-03f4-ba9f-caa893ca10fb@huawei.com>
Date: Thu, 22 Feb 2024 17:41:58 +0800
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On 2024/2/9 1:25, Andy Shevchenko wrote:
> On Thu, Feb 08, 2024 at 09:27:57AM +0100, Jiri Slaby wrote:
>> On 08. 02. 24, 8:52, Yicong Yang wrote:
> 
> ...
> 
>>>   static int __serial_port_busy(struct uart_port *port)
>>>   {
>>> -	return !uart_tx_stopped(port) &&
>>> -		uart_circ_chars_pending(&port->state->xmit);
>>> +	if (uart_tx_stopped(port))
>>> +		return 0;
>>> +
>>> +	if (uart_circ_chars_pending(&port->state->xmit))
>>> +		return -EBUSY;
>>
>> Why do you do this change at all? If anything, __serial_port_busy() should
>> be made to return a bool and not to return an error. Look how it is named --
>> returning EBUSY is sort of unexpected in my eyes. And if this needed to be
>> done, it should have been in a separate patch anyway.
> 
> I proposed that with a renaming, so it won't look as boolean.
> And I also implied (sorry if it was unclear) that this has to be
> done separately, so we are on the same page about this.
> 

Seems I misunderstand the comment from Andy. Will drop this change which should be
a separate one besides the fix. Will respin a v4 which only narrow the lock region
based on v2 (per Andy).

Thanks.