Re: [PATCH 1/3] media: rc: meson-ir: support rc driver type RC_DRIVER_SCANCODE

From: Zelong Dong <Zelong.Dong@amlogic.com>
To: Sean Young <sean@mess.org>
Cc: Neil Armstrong <neil.armstrong@linaro.org>,
	Mauro Carvalho Chehab <mchehab@kernel.org>,
	Rob Herring <robh+dt@kernel.org>,
	Jerome Brunet <jbrunet@baylibre.com>,
	Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
	Conor Dooley <conor+dt@kernel.org>,
	Kevin Hilman <khilman@baylibre.com>,
	Martin Blumenstingl <martin.blumenstingl@googlemail.com>,
	linux-media@vger.kernel.org, linux-amlogic@lists.infradead.org,
	devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org,
	Qianggui.Song@amlogic.com, Yonghui.Yu@amlogic.com,
	kelvin.zhang@amlogic.com
Subject: Re: [PATCH 1/3] media: rc: meson-ir: support rc driver type RC_DRIVER_SCANCODE
Date: Wed, 6 Sep 2023 18:37:41 +0800	[thread overview]
Message-ID: <448f6dab-4cfe-c840-8c70-adfa217cc7f3@amlogic.com> (raw)
In-Reply-To: <ZPGahNKlq/31MXbh@gofer.mess.org>

在 2023/9/1 16:02, Sean Young 写道:
> On Thu, Aug 31, 2023 at 08:13:22PM +0800, Zelong Dong wrote:
>> 在 2023/8/29 15:39, Sean Young 写道:
>>> On Fri, Aug 25, 2023 at 07:53:08PM +0800, zelong dong wrote:
>>>> From: Zelong Dong<zelong.dong@amlogic.com>
>>>>
>>>> Meson IR Controller supports hardware decoder in Meson-S4 and later
>>>> SoC. So far, protocol NEC could be decoded by hardware decoder.
>>> On Meson-S4, only the hardware decoder for NEC can be used using this
>>> driver. Does the Meson-S4 hardware support software decoding? If
>>> software decoding could be used, then any protocol could be supported,
>>> not just NEC.
>>>
>>> Also, out of interest, is there are documentation available for this
>>> hardware?
>>>
>>> Thanks,
>>>
>>> Sean
>>>
>> Yes, IR driver still supports SW decoding on Meson-S4. The decode mode could
>> be changed by 'support_hw_decoder'.
> 
> This requires changing the source code, it cannot be done at runtime.
> 
>> If IR Controller works in SW decoding, driver will be registered by
>> RC_DRIVER_IR_RAW and allows all protocol.
>> Otherwise, driver will be registered by RC_DRIVER_SCANCODE and only allows
>> NEC.
>>
>> 489         if (ir->rc->driver_type == RC_DRIVER_IR_RAW) {
>> 490                 ir->rc->allowed_protocols = RC_PROTO_BIT_ALL_IR_DECODER;
>> 491                 ir->rc->rx_resolution = MESON_RAW_TRATE;
>> 492                 ir->rc->min_timeout = 1;
>> 493                 ir->rc->timeout = IR_DEFAULT_TIMEOUT;
>> 494                 ir->rc->max_timeout = 10 * IR_DEFAULT_TIMEOUT;
>> 495         } else if (ir->rc->driver_type == RC_DRIVER_SCANCODE) {
>> 496                 ir->rc->allowed_protocols = RC_PROTO_BIT_NEC;
>> 497                 ir->rc->change_protocol = meson_ir_hw_decoder_init;
>> 498         }
> 
> There are other drivers too which can do hardware decoding and software
> decoding. Ideally we should have a mechanism to switch between them at
> runtime, but as-is rc-core does not provide for this.
Anything else I should update for this patchset?
> 
>> Do you get Meson-S4 datasheet? Please refer to chapter 13.5 Infrared Remote.
> 
> I did not get it, unfortunately. Any help would be appreciated, thanks.
Sorry, this document is not public and I don't have permission to share 
with you. Perhaps you could apply to xiaohong.zou@amlogic.com for 
Meson-S4 datasheet.
> 
> Other than that, the driver does look fine. Nothing to hold up merging for.
> I'll apply it when I can.
> 
> Thanks,
> 
> Sean