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	Fri, 27 Sep 2024 10:39:17 +0200
Date: Fri, 27 Sep 2024 10:39:16 +0200
From: Johan Hovold <johan@kernel.org>
To: John Keeping <jkeeping@inmusicbrands.com>
Cc: linux-sound@vger.kernel.org, Jaroslav Kysela <perex@perex.cz>,
	Takashi Iwai <tiwai@suse.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Alex Elder <elder@kernel.org>,
	Jonathan Cameron <Jonathan.Cameron@huawei.com>,
	Lee Jones <lee@kernel.org>,
	Francesco Dolcini <francesco.dolcini@toradex.com>,
	"Jiri Slaby (SUSE)" <jirislaby@kernel.org>,
	Rob Herring <robh@kernel.org>, Daniel Kaehn <kaehndan@gmail.com>,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH] ALSA: serial-generic: explicitly disable flow control
Message-ID: <ZvZvNIOLX1UMJmC3@hovoldconsulting.com>
References: <20240926104404.3527124-1-jkeeping@inmusicbrands.com>
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In-Reply-To: <20240926104404.3527124-1-jkeeping@inmusicbrands.com>

On Thu, Sep 26, 2024 at 11:44:03AM +0100, John Keeping wrote:
> The serdev subsystem does not specify the default state of flow control
> when opening a device.

This bit isn't correct as serdev enables hardware flow control (CRTSCTS)
by default on open() (see ttyport_open()).

> Surveying other drivers using serdev shows the
> vast majority of these set flow control explicitly after opening the
> device.
> 
> MIDI does not use flow control, so ensure it is disabled.

Johan