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X-OriginatorOrg: opensource.cirrus.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 08 Oct 2025 20:18:20.8588 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: b3f8e032-09d9-46b3-0ef0-08de06a7d382 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-MN1PEPF0000ECDB.namprd02.prod.outlook.com X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: LV8PR19MB8653 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUxMDA4MDE0MSBTYWx0ZWRfX+OLQA2su13+6 4dqV4zf2Ohc/01aDf+3I7fuN9lT5BpOxkD9FX3eAEA7F1koCsF4Zl+QfUYNE7Xk1UDJI6MkFKUF Fr5rgWnIhkpl6c0yr7bk98aioKIjvdZy3QnX9Oa9TALuukFyWGT8Gg7AP5CzKZLmDL++cK+2ybb iaGPocFMfal/hEdj9+KaRW5BIrzBI5IOjKHm0Mtrb2kDKUgDGrJhqLe+cazpQcVbjADmcWfY4/N yirlIRM/Tirwtnxz+GUea8kBVpzmoYfz3fMA8kg/9ssfMreuyDOpSaKXPkqWQ0vuKrRkuV9bwmT +V3jI8bTnrIH7j6PnEUTiQ1U6LlzvelSAmsnrOCNRBw/LvQEP0MpHClDQUQVZO/ExxxwJd+Mjma 7IGN2xlf/HWUQSMvX19o7nFlBDjD+Q== X-Proofpoint-ORIG-GUID: pKM9DGGeEUVzxOEHpFOXLPtL6JZTe7hy X-Proofpoint-GUID: pKM9DGGeEUVzxOEHpFOXLPtL6JZTe7hy X-Authority-Analysis: v=2.4 cv=McNhep/f c=1 sm=1 tr=0 ts=68e6c717 cx=c_pps a=H30LXO4bGSsCHJ4yv39IxA==:117 a=h1hSm8JtM9GN1ddwPAif2w==:17 a=6eWqkTHjU83fiwn7nKZWdM+Sl24=:19 a=z/mQ4Ysz8XfWz/Q5cLBRGdckG28=:19 a=IkcTkHD0fZMA:10 a=x6icFKpwvdMA:10 a=RWc_ulEos4gA:10 a=w1d2syhTAAAA:8 a=kWJrM743YIWaU0uNr3sA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 a=cPQSjfK2_nFv0Q5t_7PE:22 X-Proofpoint-Spam-Reason: safe On Thu, Oct 09, 2025 at 02:27:19AM +0800, Sune Brian wrote: > Charles Keepax 於 2025年10月9日 週四 上午1:16寫道： > Document had read and indeed it mentioned it will be ignored. > I apologized on my strong words about IIS standard about extra bit clocks. > However, it just mentioned if there are additional bit happens will be ignored. > It never said this is a way to relay between MCLK LRCLK and BCLK. > As such I am still don't convinced this is a proper way to reach the > targeted S.R. > And my stand of MCLK <-> BCLK <-> LRCLK relationship still holds strong. Ah, I see what you are getting at. Yes if the LRCLK is generated from the BCLK then the LRCLK would stretch/squash to always provide enough bandwidth. However, I believe most of the Wolfson parts from this era generate the LRCLK from the internal SYSCLK directly. By the looks of the datasheet on this part there is a fixed 256 divide from SYSCLK to the LRCLK. That said though, this part does somewhat pre-date me so I could be wrong. If you have hardware and an oscilloscope this should be pretty simple to verify in practice? > No matter how you do it, it will only result in a close result but not > match result. > Doing faster BCLK but unnecessary just make setup/slack timing issues. > Any specifications on how much you can overrun from first place? > Which make zero sense and reason to do so from first place. There are generally two reasons to run a faster than needed BCLK: 1) Because you can't generate the actual BCLK. 2) Because you are TDMing multiple devices onto the bus. ie. something else is using those extra bits. > If BCLK is slow then the final S.R. is slowed this is what it is. > Same as BCLK is fast then S.R. is fasted as it is. > As for this patch do the current version introduce any error or bug. > If not then I will stop the patching. > Leave it to other to patch the approximated BCLK. That is absolutely your choice. The patch should I think work now, but could still use a little tidy up to remove the unneeded code and big warning for something that isn't an issue. Thanks, Charles