From mboxrd@z Thu Jan  1 00:00:00 1970
From: Greg KH <gregkh@suse.de>
Subject: Re: uart ops tx_empty lock
Date: Sat, 12 Feb 2011 08:11:04 -0800
Message-ID: <20110212161104.GA26545@suse.de>
References: <AANLkTimpEcfmJ5SF_YpG1mE0eBiARQ7L17Pd+ay_OQoV@mail.gmail.com>
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To: Richard Zhao <linuxzsc@gmail.com>
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On Sat, Feb 12, 2011 at 09:16:45PM +0800, Richard Zhao wrote:
> Hi Greg,
> 
> Does uart_ops.tx_empty need to hold port->lock?
> I find some drivers hold the lock in tx_empty hook, for example 8250.
> But many more drivers don't hold it, for example imx.c, sh-sci.c.

I do not know, Alan would know best about this.

Alan?

thanks,

greg k-h