Received-SPF: pass (google.com: domain of linux-kernel+bounces-26252-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45d1:ec00::1 as permitted sender) client-ip=2604:1380:45d1:ec00::1;
Message-ID: <b7f76546-9998-43e0-abff-a4e73817dbae@wolfvision.net>
Date: Mon, 15 Jan 2024 17:24:27 +0100
User-Agent: Mozilla Thunderbird
Subject: Re: [PATCH 2/3] ASoC: dt-bindings: xmos,xvf3500: add bindings for
 XMOS XVF3500
Content-Language: en-US
To: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
 Rob Herring <robh+dt@kernel.org>,
 Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
 Conor Dooley <conor+dt@kernel.org>, Liam Girdwood <lgirdwood@gmail.com>,
 Mark Brown <broonie@kernel.org>, Jaroslav Kysela <perex@perex.cz>,
 Takashi Iwai <tiwai@suse.com>
Cc: Rob Herring <robh@kernel.org>, devicetree@vger.kernel.org,
 linux-kernel@vger.kernel.org, linux-sound@vger.kernel.org
References: <20240115-feature-xvf3500_driver-v1-0-ed9cfb48bb85@wolfvision.net>
 <20240115-feature-xvf3500_driver-v1-2-ed9cfb48bb85@wolfvision.net>
 <333c2986-c7c2-4a46-90cf-b59ae206e55a@linaro.org>
 <96abddcc-fa65-4f27-84fe-2281fe0fcf1c@wolfvision.net>
 <644f7f02-405d-47fb-bc72-4d54e897255f@linaro.org>
 <5db4b898-93d5-446f-bfed-b57847f9967a@wolfvision.net>
 <435f502c-1e1b-4d40-8dcc-34487905d69c@linaro.org>
From: Javier Carrasco <javier.carrasco@wolfvision.net>
In-Reply-To: <435f502c-1e1b-4d40-8dcc-34487905d69c@linaro.org>
Content-Type: text/plain; charset=UTF-8
Precedence: bulk
MIME-Version: 1.0
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0:
	=?utf-8?B?VVNGWkplWXJCeno0Q3VFN1dJL2U3eDJFV3RqdlYrK2pKMGg1T3FJS3RFNjlB?=
 =?utf-8?B?VEtEM1pMNTlUdFJZWFRyNjJORitTeTRONk5OZXJqb1hUaFBoNFRtZStYMll1?=
 =?utf-8?B?cTNjV1lUR1dEMkVXQ3Z0RlY0R1VDVnBtRW9WbGtOMGJsZ2xqcnhZSVdQUUJy?=
 =?utf-8?B?bUhqRW9jK255M0RwRFhpRVNzOTZna25HTmJNUk1pSjhnQkdVd1YrV1lyVTZ1?=
 =?utf-8?B?TllZcjBDRThma2ZoMWdlSU9WYjBwVVY5Vjd6cmJneWloMDhxKzNEcGFMbHBo?=
 =?utf-8?B?dHFKdVU1VCtxdFhFNzgrRkE2TksxbFRDNGw1NWV2bGhTdlNNeS9FNytrb2Nt?=
 =?utf-8?B?aXduK0VaMW0vQ3dZV2FZSXR1SUtnc1JGMjA5UTdaU2RleENOSFFNNDlWelNi?=
 =?utf-8?B?ZjVGcGJrYnhvRlNWd21YeU0xcWQrUVVRN29KY3NDQkY2YXJFZXE5M1dybjJm?=
 =?utf-8?B?N1FRYi9RRHdCSXcweWhiSEkxUmgzRFEzbGVQdXBlS3R0emJxdDNROFNnYlJQ?=
 =?utf-8?B?dU9yOFBMS1RIOGlkcnBwdnBKZ2drN0ExWUNnYXNoTEZXZCtJTFZEWVduYnp6?=
 =?utf-8?B?aG1rTnQ2VTlibXArWjFnWlJXaGUvaTJXdzhXU01qbzAvVFNZT0YvR3dKbWk4?=
 =?utf-8?B?RWhDczJldkxoY0hUdHZzMWVsWUUwUzdHclVsYXI1cDNJbitIMjQweFJ0LzVk?=
 =?utf-8?B?akRQVjJCM014SzBkc3NFamw4UWdkUXEyaUg1UmtMUStuUzJWQWxFS2hTLzZp?=
 =?utf-8?B?d3hpUDZydzBuNEk2czZzRGFpNWdVZk5wUkZETjhyS2orU3JUYWRjb1FoOTJG?=
 =?utf-8?B?NDBRaGVZeGxOWno1NHlaYWFzRVdicnNydlNYYmNnU0Yxak5iYVJkRWtFR1lh?=
 =?utf-8?B?ODJ3dEZIUEdFQWZyc1ptb2JuOUdQaXBaSTN1V0xUM3lxU05LRkhCbUdrT0JO?=
 =?utf-8?B?SzBWREorSzdHQ01CNEo0N2lVZWJVQnhCYzNxb2RjZ0VTYTB5b2dobGtjK2tv?=
 =?utf-8?B?Umprdi8zd1Z0MGY3c0FvSXpGajJGUXk3NmhROWZCME04SlRPelhMa0RtRXFm?=
 =?utf-8?B?dHZPUG96bmNaVmhBZm9YSjA2N2RmOHNldkZVbmJYOUEycVBSWUtMa2NzMVVC?=
 =?utf-8?B?SUFzVjdacU9WVTErZWhqZnN4T1piazRzVVoxeHFUdHlhSm8zNGY0VFIzSzhm?=
 =?utf-8?B?WDlkbGNRcHRaRkp3aUJLVlBPYXBrTkg1RkhlejhvdXB4UUdwM3EzQlBXbHh4?=
 =?utf-8?B?RUhvYlhPRzhiN1VKUGd3RUhGVnlxR0RQeUFhR0Y5Z2NwZHdwdWNBaXN0YlJx?=
 =?utf-8?B?V1RmWWhBb3h5SmhyazBuYTRialNyTFVXYXFBekxRNlFCV01KaWkyNFBQUllE?=
 =?utf-8?B?dlNXeXZGMHg5SmUrU1VIL1EwYy9qT3ZETHlNZFFMdVN1WFh1c1BQR1hsakgv?=
 =?utf-8?B?RnA2dWRYNy92YWoweERQY3lRTDlpNzRhMnRkVFdhLzE0d1AwcC84MHd3ai9S?=
 =?utf-8?B?cUJFcENkMDZVVEg5a3FKNUkwdFl2czVjekIyeWw1Y2Vaek00RHNDd1Q3S0NK?=
 =?utf-8?B?OHA4VzBzdlF4QklyblNBNGVNbHY4ZlgxNktDMzU3d25yanU5TEtqcjZSK0Jm?=
 =?utf-8?B?TkI2VHBMNHFQNTZVRTRuREphbGpHbmJ1a3VEV2VRZTR5U09OWE5jZW8waGVV?=
 =?utf-8?B?eHg2bEZ6VHJhRWlKS0NvZFhvTVYwZ054NDZuTUx1YUdKbDkzT2psRmwxZEE4?=
 =?utf-8?B?eldQNGFSd0RGQUVERHI0L3hJSlpMYWRLY2hUMXNXTHZ1L3RjZVhiSEZYNzlD?=
 =?utf-8?B?MHdXeE1DMlFneWtJSWtmUFNJZUlpNFFHSllIQnBKTFN5RzV1SzNpRS83N1A2?=
 =?utf-8?B?T1BpeDE0NjUyWXpucUVzcVRZcDZnWDVNbHlwNnpkcU9DN0w2ODB6dVM0UElS?=
 =?utf-8?B?SWNMdHBQRFRQWWRidzlwMDBVaXJ2RHNKWW9FVW95YnpuL09teUZabWg3alNS?=
 =?utf-8?B?L0tHVDZ1RVZPT1lEcWRCakF6Ry9RQ2dKR2l6bWZqRGlnK2M1WVhHSFdLZTRt?=
 =?utf-8?B?cFAyQlBoamplcFlGMHNrbktiVkRUREk1WWZzb2VxTmM4ZUtuQWZzUE96OUVk?=
 =?utf-8?B?UWxjRXdKYjZrTy9XRElOK0tFY1ppQWhIOUdsd3FsaS9wc3hqNU9LTVd6R2pK?=
 =?utf-8?Q?BDwd81YCRYDSmyn2AkhCrbo=3D?=
X-OriginatorOrg: wolfvision.net
X-MS-Exchange-CrossTenant-Network-Message-Id: 86446e70-a6d9-4df9-fbb8-08dc15e672a5
X-MS-Exchange-CrossTenant-AuthSource: VE1PR08MB4974.eurprd08.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 15 Jan 2024 16:24:29.1460
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: e94ec9da-9183-471e-83b3-51baa8eb804f
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: zH9rlN5IMy0uSGjzuK/veTCLKeGV/48v9seRQRNoLS6UI+z2abhvLXreDUcINjVXttkS5h5V54uWzAAeL0oWyb+4Fr8vSYjO5YQ1w5nBp0k=
X-MS-Exchange-Transport-CrossTenantHeadersStamped: GVXPR08MB10542


On 15.01.24 17:03, Krzysztof Kozlowski wrote:
> On 15/01/2024 16:59, Javier Carrasco wrote:
>>>> The voice data and any other information can be retrieved directly via
>>>> USB from userspace. Once in normal operation, the device acts as a
>>>> regular "onboard" USB device and the driver does not need to do any
>>>> further management.
>>>
>>> So is this an USB device? If yes, then shouldn't be just auto-discovered
>>> and you add here some bindings for other device? This looks like coding
>>> power sequence not in USB node, but in some other, new node.
>>>
>>> Best regards,
>>> Krzysztof
>>>
>> It is an USB device that requires two power supplies and a reset to
>> boot. Afterwards it is auto-discovered and functions normally as a
>> regular USB device. In that sense it works like the onboard USB HUBs:
>>
>> https://github.com/torvalds/linux/blob/master/drivers/usb/misc/onboard_usb_hub.c
>>
>> The onboard USB HUB driver is of course more complex because it has to
>> support other features, but the idea of enabling the power supplies and
>> toggling the reset signal is essentially the same.
>>
> 
> Yeah, about that... so this is not really correct device representation
> for DT. There is no such device as XVF3500 outside of USB bus. There is
> XVF3500 but on USB bus and this should be there. In the past we allowed
> such root-level devices just because we did not have other way to handle
> them. Now we have.
> 
> Best regards,
> Krzysztof
> 

Do you mean that the XVF3500 should not be represented as a platform
device and instead it should turn into an USB device represented as a
node of an USB controller? Something like this (Rockchip SoC):

&usb_host1_xhci {
	...

	xvf3500 {
		...
	};
};

Did I get you right or is that not the correct representation? Thank you
again.

Best regards,
Javier Carrasco