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Date: Fri, 06 Apr 2012 15:01:38 -0600
From: Stephen Warren <swarren@wwwdotorg.org>
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To: Dan Williams <dan.j.williams@intel.com>
CC: gregkh@linuxfoundation.org, Sudhakar Mamillapalli <sudhakar@fb.com>,
        linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org,
        Colin Cross <ccross@android.com>, Olof Johansson <olof@lixom.net>,
        Nhan H Mai <nhan.h.mai@intel.com>, Alan Cox <alan@lxorguk.ukuu.org.uk>,
        alan@linux.intel.com
Subject: Re: [PATCH 4/6] tegra, serial8250: add ->handle_break() uart_port
 op
References: <20120406184346.21744.18004.stgit@dwillia2-linux.jf.intel.com> <20120406184956.22088.85217.stgit@dwillia2-linux.jf.intel.com>
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On 04/06/2012 12:49 PM, Dan Williams wrote:
> The "KT" serial port has another use case for a "received break" quirk,
> so before adding another special case to the 8250 core take this
> opportunity to push such quirks out of the core and into a uart_port op.

This doesn't seem quite right. Why do the board files have to set up
this .handle_break function; they're already setting .type=PORT_TEGRA,
which should be enough to drive the setup of any required quirks.

If plat_serial8250_port must contain this field, then
drivers/tty/serial/of_serial.c needs a similar change so that this all
works when booting using device tree.

I'm not sure what the implication is of moving the call to clr_fifo()
into uart_handle_break(). What's the benefit of one location over the other?

If the callback function is to no longer live in 8250.c itself,
arch/arm/mach-tegra/devices.c isn't logically a good place to put it,
and that file will be going away once we get rid of all the board files
and move solely to device tree.