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Subject: Re: [PATCH 01/36] serial: Add uart_rs485_config()
To:     Lukas Wunner <lukas@wunner.de>,
        =?UTF-8?Q?Ilpo_J=c3=a4rvinen?= <ilpo.jarvinen@linux.intel.com>
Cc:     linux-serial@vger.kernel.org, Greg KH <gregkh@linuxfoundation.org>,
        Jiri Slaby <jirislaby@kernel.org>,
        Shawn Guo <shawnguo@kernel.org>,
        Sascha Hauer <s.hauer@pengutronix.de>,
        Pengutronix Kernel Team <kernel@pengutronix.de>,
        Fabio Estevam <festevam@gmail.com>,
        NXP Linux Team <linux-imx@nxp.com>,
        linux-kernel@vger.kernel.org,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>
References: <20220606100433.13793-1-ilpo.jarvinen@linux.intel.com>
 <20220606100433.13793-2-ilpo.jarvinen@linux.intel.com>
 <20220625201912.GA29720@wunner.de>
From:   Lino Sanfilippo <LinoSanfilippo@gmx.de>
Message-ID: <918ab6d2-c0f8-fd74-8e80-36d86ba82255@gmx.de>
Date:   Sun, 26 Jun 2022 14:36:51 +0200
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On 25.06.22 at 22:19, Lukas Wunner wrote:

>
> Why doesn't this helper acquire the port spinlock, unlike
> uart_set_rs485_config()?  Is this safe?  Do all callers hold the lock?
> Do we need an assertion to verify the lock is held?
>

AFAIU the callers are using this only during initialization, so there is n=
othing else
at this time that accesses the serial_rs485 struct and thus no need for lo=
cking.

Regards,
Lino