From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B19F12D73B1; Tue, 13 Jan 2026 15:05:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768316704; cv=none; b=E17MnfagPZmwtYPUr/AxKdl9DAwVhUnapKD0qVgTfcDlQJ5vS/RiXHwgxauJQ090nKSpgXrNdLLF6QFsl14sIYUn7eBnsUDazQRGMJC0SjX6ReWjUOCy3zEhEJCNN/MOEO4p8uc4TNxxZfs0TFu7NMm9ncZHSur5Jo6y0fCvkXQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768316704; c=relaxed/simple; bh=L/OG+rJQNDo22V3cJZEIJYiPUAWGK9C0kRDuAD79rz4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=LG34VfQnx0/eJhECL9nE3bgQHuGwCB10H7y1zobNomXq/Ykl03RpsLjAMi3IXIGk3j1Xq1+UBPvbluJAtDBj6N9uKQulrZIKa7g7HV2an0ynoY6AKM0cvOtvgH2+y7XY0YnODLAgy2PgB6b453S4j8Db4rrDihpL2WGgHSB8R9E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=JmQuJ3Vl; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="JmQuJ3Vl" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8A31DC116C6; Tue, 13 Jan 2026 15:05:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1768316704; bh=L/OG+rJQNDo22V3cJZEIJYiPUAWGK9C0kRDuAD79rz4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=JmQuJ3VlG8fecaDG31EVIQIDwAznKaf30jphVjzuRgJNzcvcJGIshYC9Ux9SI23ZF x/BeuKvKXM6hfp2jjcuhlmVDHdbiZgIwkOP9uk80HinjklltsVXR9Gx/ecad+4xDUO rnbjXtGtK3g0Ug3KZkAYmvtLKu9+uVxqAl4SIf4Jug+a7CyCrOyo827aXJupHbU/MA YlxhXJRO2gbcjTldcmpNqUY57HY7HUZJJ+HJiCutSBEXZjqwsPxn8TctDqp8rHOw6Y M2VO/WsY2GZDR9WJDYZ+bfK/ooA1t/1hF5hhPAeV1siFA3butGFnTbP1XB5ENgZbKp /tQazXji2J3xA== Received: from johan by xi.lan with local (Exim 4.98.2) (envelope-from ) id 1vffx4-000000002aY-19U3; Tue, 13 Jan 2026 16:04:58 +0100 Date: Tue, 13 Jan 2026 16:04:58 +0100 From: Johan Hovold To: "Ji-Ze Hong (Peter Hong)" Cc: hpeter+linux_kernel@gmail.com, gregkh@linuxfoundation.org, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, tom_tsai@fintek.com.tw, yu_chen@fintek.com.tw Subject: Re: [PATCH V3 1/1] USB: serial: f81232: fix incomplete serial port generation Message-ID: References: <20251212070831.16334-1-peter_hong@fintek.com.tw> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20251212070831.16334-1-peter_hong@fintek.com.tw> On Fri, Dec 12, 2025 at 03:08:31PM +0800, Ji-Ze Hong (Peter Hong) wrote: > The Fintek F81532A/534A/535/536 family relies on the > F81534A_CTRL_CMD_ENABLE_PORT (116h) register during initialization to > both determine serial port status and control port creation. If the > driver experiences fast load/unload cycles, the device state may becomes > unstable, resulting in the incomplete generation of serial ports. > > Performing a dummy read operation on the register prior to the initial > write command resolves the issue. This clears the device's stale internal > state. Subsequent write operations will correctly generate all serial > ports. > > This patch also removes the retry loop in f81534a_ctrl_set_register() > because the stale state has been fixed. > > Tested on: HygonDM1SLT(Hygon C86 3250 8-core Processor) > > Signed-off-by: Ji-Ze Hong (Peter Hong) > --- Next time, please remember to include a short changelog here under the cut off line (---). Now applied, thanks. Johan