Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
IronPort-SDR: 90cM5wyiVTkRt1gQbOKr+m+Gvo0vJ5g2wZ8iwVhye4HtVaHi0Dr5adrCFPvNfN4ylW3s29ko1z
 3ivyp59KvNqw==
IronPort-SDR: moMPn00gvSZCt+UezBpZ7wwZYzT4zWMIrShx2RULg13yS8k8EYKpYFVSEU+ImgSugF3lwKsHQm
 KBdglL1MkTPA==
Date:   Tue, 2 Feb 2021 13:22:11 +0200
From:   Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To:     Giulio Benetti <giulio.benetti@micronovasrl.com>
Cc:     Heiko Stuebner <heiko@sntech.de>, gregkh@linuxfoundation.org,
        jslaby@suse.com, matwey.kornilov@gmail.com, lukas@wunner.de,
        linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org,
        christoph.muellner@theobroma-systems.com,
        Heiko Stuebner <heiko.stuebner@theobroma-systems.com>
Subject: Re: [PATCH v3 5/5] serial: 8250_dw: add em485 support
Message-ID: <YBk14xJhIyqTNH/k@smile.fi.intel.com>
References: <20200517215610.2131618-1-heiko@sntech.de>
 <20200517215610.2131618-6-heiko@sntech.de>
 <20200518152103.GI1634618@smile.fi.intel.com>
 <1f7881b5-f900-dbbe-3f8d-f990d2bdf5a7@micronovasrl.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <1f7881b5-f900-dbbe-3f8d-f990d2bdf5a7@micronovasrl.com>
Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo
Precedence: bulk

On Tue, Feb 02, 2021 at 01:31:17AM +0100, Giulio Benetti wrote:
> Il 18/05/2020 17:21, Andy Shevchenko ha scritto:
> > On Sun, May 17, 2020 at 11:56:10PM +0200, Heiko Stuebner wrote:
> > > From: Giulio Benetti <giulio.benetti@micronovasrl.com>
> > > 
> > > Need to use rs485 transceiver so let's use existing em485 485 emulation
> > > layer on top of 8250.
> > > 
> > > Add rs485_config callback to port and uses the standard em485 start and
> > > stop helpers.
> > 
> > Would it prevent to use native RS485 support?
> 
> 8250_dw doesn't have a native RS485 support, do you mean using hardware
> RTS assertion? Anyway at the moment it's not present. This would be the
> first rs485 support added to 8250_dw.

DW v4.0+ has it.

-- 
With Best Regards,
Andy Shevchenko