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Date:   Sun, 6 Aug 2023 18:16:23 +0800
From:   Jisheng Zhang <jszhang@kernel.org>
To:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc:     Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>,
        Ilpo =?utf-8?B?SsOkcnZpbmVu?= <ilpo.jarvinen@linux.intel.com>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Jiri Slaby <jirislaby@kernel.org>,
        linux-serial@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 0/2] serial: 8250_dw: fall back to poll if there's no
 interrupt
Message-ID: <ZM9y93rVVnIIQzzP@xhacker>
References: <20230806092056.2467-1-jszhang@kernel.org>
 <2023080643-chalice-exploring-e7ca@gregkh>
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On Sun, Aug 06, 2023 at 12:20:11PM +0200, Greg Kroah-Hartman wrote:
> On Sun, Aug 06, 2023 at 05:20:54PM +0800, Jisheng Zhang wrote:
> > When there's no irq(this can be due to various reasons, for example,
> > no irq from HW support, or we just want to use poll solution, and so
> > on), falling back to poll is still better than no support at all.
> 
> Ouch, really?  Why not just fix the hardware instead?
> 

Hi Greg,

The HW may be designed as that to save interrupt lines if the uart
is dedicated to debug purpose. I also see similar support in other
uart drivers, for example liteuart.c, altera_uart.c, altera_jtaguart.c
8250_ioc3.c and so on.

Thanks