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References: <20220628134234.53771-1-ilpo.jarvinen@linux.intel.com> <20220628134234.53771-5-ilpo.jarvinen@linux.intel.com>
In-Reply-To: <20220628134234.53771-5-ilpo.jarvinen@linux.intel.com>
From:   Andy Shevchenko <andy.shevchenko@gmail.com>
Date:   Tue, 28 Jun 2022 22:11:14 +0200
Message-ID: <CAHp75Vf36sFqX1SL4Sjz6ZgNXP41Nom0Q1s6Psgv9WMFkKtGtg@mail.gmail.com>
Subject: Re: [PATCH 4/4] serial: 8250_dw: Rework ->serial_out() LCR write
 retry logic
To:     =?UTF-8?Q?Ilpo_J=C3=A4rvinen?= <ilpo.jarvinen@linux.intel.com>
Cc:     "open list:SERIAL DRIVERS" <linux-serial@vger.kernel.org>,
        Greg KH <gregkh@linuxfoundation.org>,
        Jiri Slaby <jirislaby@kernel.org>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Tue, Jun 28, 2022 at 3:43 PM Ilpo J=C3=A4rvinen
<ilpo.jarvinen@linux.intel.com> wrote:
>
> Currently dw8250_verify_write() (was dw8250_check_lcr()) nullifies the
> benefit from differentiated ->serial_out() by having big if tree to
> select correct write type.
>
> Rework the logic such that the LCR write can be retried within the
> relevant ->serial_out() handler:
>   1. Move retries counter on the caller level and pass as pointer to
>      dw8250_verify_write()
>   2. Make dw8250_verify_write() return bool
>   3. Retry the write on caller level (if needed)

I'm wondering if it's possible to utilize one of iopoll.h macro here
instead of copying retries and that not-so-obvious IO poll write.

--=20
With Best Regards,
Andy Shevchenko