From mboxrd@z Thu Jan  1 00:00:00 1970
From: Johan Hovold <johan@kernel.org>
Subject: Re: [PATCH v5 2/5] Bluetooth: hci_qca: Deassert RTS while baudrate
 change command
Date: Fri, 18 Jan 2019 10:44:16 +0100
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To: Matthias Kaehlcke <mka@chromium.org>
Cc: Johan Hovold <johan@kernel.org>, Balakrishna Godavarthi <bgodavar@codeaurora.org>, marcel@holtmann.org, johan.hedberg@gmail.com, linux-kernel@vger.kernel.org, linux-bluetooth@vger.kernel.org, hemantg@codeaurora.org, linux-arm-msm@vger.kernel.org, Johan Hovold <jhovold@gmail.com>
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On Thu, Jan 17, 2019 at 09:21:09AM -0800, Matthias Kaehlcke wrote:

> I observed that the qcom_geni_serial driver doesn't raise RTS with
> flow control disabled. It seems we have to investigate why that's the
> case. I agree that the driver should be platform agnostic.

Sounds like a driver bug, unless the hardware is just "odd". The
driver implementation of this looks very non-standard judging from a
quick peek.

In fact, qcom_geni_serial_get_mctrl() is currently a no-op if hardware
flow control is not enabled:

	if (uart_console(uport) || !uart_cts_enabled(uport))
		return;

Perhaps dropping the !uart_cts_enabled() test is sufficient.

Johan