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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: t+nx8PDCtiBlT3mm28hO7Yj96blhV5e6JuGugIbNvq7oLsdckCP798VhKZk+ApH2SW8PQi7Z2J9LlEwZTJlu4WFs32+R/PYLrbJNDn3lGLwiECrJugln3zj3aHu+GohAtiRsCFkxgVDMvvAyS1GpZEf9W0pu4bI4taByKWSrwM/7Vb07+TiKpP/swzttaWNp/bYpJgtOjPO9KZwB9w85sbgjntEqWFt7Iq06IwQ1GX19NB0nfS7W0WhHUMYxQYMuPO/F6jEfUPxLjzrvmjsJ4pCq4NXMXt6sWlL9R7j1MbwLtIknNOfs70ggLKDc4EKqRHSJYczZgkbcimawK1Box8ip8z5fWgpyL8ZF6+AWfXF8YSLMxMt7GGxtx9YKRY+WSHAqkM1Q5XnLdk7ZqmYP0PdQykGWF7s+n3V6AcBysCqMPG6kWMCKgyGShRlzfEj1 X-Exchange-RoutingPolicyChecked: Cczvu39kogWLXNUbmQ0OwVNuxfbHw9AMIjUpOnxBztT93PqvPeAeuUpo97Tx+7JCr3NEji5z7XfKzjZW7pLDeNu8K5lfrf8GVzjXq+HD4o9DH0bAliz7ZQrLXzyL3gXnjSFrlMqYS7QGpc5EO4pCg6FrPZ/hBKtO9sUCI6M5sItFoGFab/n+wf9kwGJiLRBQmBQDVrfySVem29w80pzElMPd42WScOVp+Du2b2ReRuq3XCZPy8tupUP/7CjR7bStNQMAynJa5IaRYsUGH1H3STdpBX+NIFnpAqomEBl6PBgGKbRqmXloXRQlRnKqqtyqDqdr1Jdp4FtpKEpEoEtOPQ== X-OriginatorOrg: opensource.cirrus.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 08 Sep 2026 13:20:16.1435 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 8ec11dac-99bc-471a-e1ae-08df0dabec41 X-MS-Exchange-CrossTenant-Id: bec09025-e5bc-40d1-a355-8e955c307de8 X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=bec09025-e5bc-40d1-a355-8e955c307de8;Ip=[84.19.233.75];Helo=[edirelay1.ad.cirrus.com] X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: TreatMessagesAsInternal-DS2PEPF00003448.namprd04.prod.outlook.com X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM4PR19MB6073 X-Authority-Analysis: v=2.4 cv=bpd8wkai c=1 sm=1 tr=0 ts=6aa00b99 cx=c_pps a=rt/ALwyEcTQPnCFk1mwiOQ==:117 a=h1hSm8JtM9GN1ddwPAif2w==:17 a=6eWqkTHjU83fiwn7nKZWdM+Sl24=:19 a=z/mQ4Ysz8XfWz/Q5cLBRGdckG28=:19 a=8nJEP1OIZ-IA:10 a=VdqzKS8jKosA:10 a=s63m1ICgrNkA:10 a=RWc_ulEos4gA:10 a=VkNPw1HP01LnGYTKEx00:22 a=iX4cTi3TZMoOKdANLEfx:22 a=KfkQE9S9VqCBgivYGm0O:22 a=jA7ODzAtdX4U5uHHI44A:9 a=3ZKOabzyN94A:10 a=wPNLvfGTeEIA:10 a=jZz-an6Pvt0H8_Yc_ROU:22 a=VlVynqX4KLlZR1Cn4-IV:22 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwOTA4MDE0MiBTYWx0ZWRfXwK82wVhdg/8f BcmU1yylt3v+E8Nz79oGFNSM4fgPs03nF/fHL44eH4bXi+VrTtd1x8/YV22bbhjhuHx/Kr4zkRi 2anHAQjqcrV3IxHGmEarQZjpOrCeU7E0D4nnCpI1zR5FKAtXX/e0j5dWiIzf+6x0hzpx6uDigLn 6kz+58vZRLxKUai5v5IFYUjymhDsGzR8IupRs06U8MQAfr9s702OhGZZaoi36+ZXpwPfCfc/A9z uDyEHQ1EKkerJfj3ENy+MAo2Epkl5ItcYNYopirLX/dJt8uULuNQ0j++/sb3yMLRtlGkpb2odQJ QbrJfMEJBARpdJmbiDGMQfPgks7NAPmCHU+kTu0pQg3Lg/SCNfmasowgdmTtE5EoZVUH6PwIofA nL/u7QrFuqQ6rpAkGRCEtoQxZ0DTGD7JrXf3819wNE4tQsD9ac0U3lBzYv5kcldLodZPmpENwn/ 1kmEWZNeL49UkYcM/FA== X-Proofpoint-ORIG-GUID: Kjm9Ig2Zh9GhdetzoNnCJ5W9WIS8uwXN X-Proofpoint-Spam-Info: AW1haW4tMjYwOTA4MDE0MiBTYWx0ZWRfX169uuXYMJiDG mEP83gwzVveix/69d26byVyn+99xvHe76vDJhpkzHBwpUrxIVrvtPTSPgz8kIxnNeJdCaRoQKvv cGDYRuE25Hf11vkcDimZ/GVPd9B44xo= X-Proofpoint-GUID: Kjm9Ig2Zh9GhdetzoNnCJ5W9WIS8uwXN X-Proofpoint-Spam-Reason: safe On Tue, Sep 08, 2026 at 01:31:37PM +0100, Srinivas Kandagatla wrote: > On 9/8/26 11:37 AM, Richard Fitzgerald wrote: > > On 08/09/2026 10:09 am, Srinivas Kandagatla wrote: > >> On 9/8/26 9:49 AM, Charles Keepax wrote: > >>> On Mon, Sep 07, 2026 at 11:37:49PM +0100, Srinivas Kandagatla wrote: > >>>> On 9/7/26 8:47 PM, Pierre-Louis Bossart wrote: > >>>>> My take is that rather than encode all properties in C, it's probably > >>>>> worth exploring a DT representation of the concepts that *can* be used > >>>>> fairly easily and make the life of codec vendors easier - not as a> > >>>>> literal translation of ACPI. > >>>> > >>>> I agree a DT expression of the *concepts*  not a literal DisCo > >>>> mirror would be a better A.  I want to bring that back to LPC 2026 > >>>> DT MC as a concrete proposal grounded in the earlier DT-maintainer > >>>> feedback rather than re-litigating it inline on this series.  Because > >>>> B stays put, switching A later is a change inside populate_function, > >>>> not an ABI break. so landing this series does not close the door on > >>>> the representation you're asking for. > >>> > >>> I am still not sure I really see what the value is in a > >>> completely different DT representation of the DisCo information, > >>> all it does is give us potential issues with future spec versions > >>> and create a whole bunch of new code than needs maintained. The > >>> ACPI representation translates perfectly well to DT, should work > >>> perfectly fine using the existing code. > >> > >> I totally agree with both of your comments, there is no way we can > >> replicate MiPi spec into an different DT representation, this brings > >> both maintenance overhead and is fragile. This a very big effort. > > > > But in your previous message in this thread you said the opposite: > > Yes I did say that, and I still think an intermediate DT > representation would be a better A in principle. What I'm > highlighting is the cost side, any intermediate representation, by > definition, deviates from the original MIPI representation. That > deviation has to be kept in sync with the SDCA spec, tracked across > spec revisions, and translated back to struct sdca_function_data at > runtime. It's a real overhead, not a blocker, just something to > weigh against the "concepts read cleaner in DT" benefit. I am very sorry but this reads quite strangely and I am really struggling to understand your position. I think I am reading it as you are happy to go with the group concensus on how the DT is represented and don't favour either approach. > That's why the current series takes the lower-overhead path > (mechanical transcription in C) rather than proposing an intermediate > DT format as part of this submission. If the concept-DT direction > gets traction at LPC 2026 DT MC, we can revisit. This part I follow slightly better, I would be happy to proceed, pending reviews with the current approach, although if Pierre is or not probably remains to be seen. I would assume the DT guys would be happy with a completely different representation that was more idiomatic DT, that is essentially what they have already said. The question I was aiming for was less whether they will be on board with that and more if it is a good idea. Thanks, Charles