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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?JvYBodxEvnUsYixqrDsORvAIbYaR8JzKaIyRxqd8801p/s+Onl1uPk2bTFpI?= =?us-ascii?Q?oEMQ988bOuD5nvjt+qtOMniOrL8xAfrcLzy2gMZ3g7Uol/M1pzr/igUy+QXj?= =?us-ascii?Q?au+68QU5+C7bs9LySV0Wxb9YPNlehhwpe46IHBQlIxC4mMQH8BnKBWynRZAr?= =?us-ascii?Q?gtPnKKSV9qtPR36D9yPESnmIKnfjvl7UsxpoKEdHnHlYv1Eeb68hKAUD7fWk?= =?us-ascii?Q?8GHium/DAaL2SkVmR0RC7GcoOWKhyEjQFo1u5NWrj4EH51eSwBOnpfi7kXBK?= =?us-ascii?Q?74poNmBgcv6RHlNMIYntEvXpAGv3xXuKwFRiBmdtXqW7YYTu7puYDcA1mL0f?= =?us-ascii?Q?A/umeOfSZMgx2kHRbZybplbpZFkn/hGzB84lKf8lFZKVOf4GeUQGp1+l3UDs?= =?us-ascii?Q?l7ZypYsRZKsQPwUW5gBZlya23NrnfbCz5QtaEnlE0UbUcBrwQwh60rcNGn9i?= =?us-ascii?Q?81xgqI3OxQUVQc79r/yttiOJJLPUJ4yclLuPrF/yMrBXyeaQmcWkxXZNsBs5?= =?us-ascii?Q?SeAtA/O5H1mtLilNIHOJbETAXGAtLeXycZAV504j4ejCVJOysnvQO0OdJvt1?= =?us-ascii?Q?C13uOFgj+3qBk0pb7+dI7KxX87n++QaQTwn/FqZOZ9tZe35nwbIWlwe/YTZR?= =?us-ascii?Q?5wPs79kjiP6YvJDFdx3VFyyQS5qcCUyIb4EKG2DAlHAChaiGjirt6yyBpkK3?= =?us-ascii?Q?Yy0U+PuORSPKXJ0QsEnCZTOWgqZKV3awdztlARI9/0JXvOSktYISoQZHmB/W?= =?us-ascii?Q?to+dee3hVk8gRFOiAIhpLZjx5Sx85LwjK00v3VDWbaQt0uafK/PK9co4X2AG?= =?us-ascii?Q?TkRrIkPyED7q0iH9GYdCfdOsiGRfKedbCqBGZTAuDfhlR5XdTvpMq2w213+t?= =?us-ascii?Q?ypBkaoNspNp/BffTAX10qizEixc4A2BvJgvomfUzzHqUkedwagvMdWJ2qvw5?= =?us-ascii?Q?S56MbpA+54i34Ez1ZZIuPiGxmZ/9E/5P6If4lFbXFKO9pe9TM8b+yqaFPcqf?= =?us-ascii?Q?jNQtdPGD96i0y+L40knHeS9X9MlOwEdDEE00fsY5RKNcBx5iW147pzjWipKi?= =?us-ascii?Q?/tTyDbcefVDL2+zBFNrXSd0rE7cXZKXobkZ206H4Yz+dj0xALeINo/5A4TVO?= =?us-ascii?Q?h/Q9caf76Euerwy0A4ZVtnKUD8Wlh3KGNu0Mq+yVdXfftUlPzuijnAonwieA?= =?us-ascii?Q?qerFK6Zqd/QqttbsOsNhIP4PJyp59cLR8/bC0fWsls0VwIANPHdlX509hEjF?= =?us-ascii?Q?kp7ccjDMDEAn+XuKYOcRqsC51xilXZo9r15+FJctbEn6mhgXhOLoW+viaan1?= =?us-ascii?Q?HLy+SN/qn8JZqZbIn/Xa+waGM1Ih8Ow3ygiXttMDRRGgMMeVzHwXtL8TAYU/?= =?us-ascii?Q?mAcGo4sHJvmpIAEGmluk+vgzBDxfFKnDXsCanSQMtxuV/yvLgjxSYxFqkwJf?= =?us-ascii?Q?0ovmH/eNeDBvQcExYaLDXh7yUTatErCXfkLUzpGDQJfB2NkH5D02fYH2agls?= =?us-ascii?Q?yM6n8MDiWQdeBd+ttmeQiBmP2nktPDhUcHNxVGlQUdjAm8hKou7L+yl6Yzfe?= =?us-ascii?Q?OyarUjzXQrnIu7xKBgXgEVJv9ehsj0PTDb7rTvopr+5JBXMZfGxgPk259QMV?= =?us-ascii?Q?PwdNgSbpuiYEZICpltPbpIbh8H6GzjocW2h7Jjw2v3MYhUI0NLqDX6G228uP?= =?us-ascii?Q?e+Xh+5c67zQtI6F2eFfSUoiItJb/MXF77EG+Wsi7phwK5SrItU/G730LTHxb?= =?us-ascii?Q?paHtVJhL2g=3D=3D?= X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: 70e378ba-408d-40de-81e4-08deab468c91 X-MS-Exchange-CrossTenant-AuthSource: AS1PR04MB9287.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 06 May 2026 08:07:42.9447 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 686ea1d3-bc2b-4c6f-a92c-d99c5c301635 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: F9mZ9x+zfUfgBSDh7K4TkMglP6VGKcGSIHhFjXsdRxlrVGj80ryXU0NaNYbM1UkzEyLOdd3FB9zGdt+eBK6gNA== X-MS-Exchange-Transport-CrossTenantHeadersStamped: AS8PR04MB8868 On Tue, May 05, 2026 at 05:45:56PM +0200, Marco Felsch wrote: > On 26-05-05, Rob Herring wrote: > > On Mon, May 04, 2026 at 10:21:42PM +0200, Marco Felsch wrote: > > > This reverts commit 16c8d76abe83d75b578d72ee22d25a52c764e14a. > > > > > > Remove the 'reg' and 'reg-names' property from the LDB. > > > > > > The LDB is either part of the IOMUX_GPR (i.MX6SX) or the BLKCTRL > > > (i.MX8MP, i.MX93) register space. Both IOMUX_GPR and BLKCTRL are > > > register ranges with loose register definitions. E.g. > > > > > > - On the i.MX8MP there is one register which controls the AXI > > > threshold for two different IPs (BIT(31:16) - IP1, BIT(15:0) - IP2). > > > - On the i.MX6SX IOMUXC_GPR5 controlls: CSI2 mux, WDOG3 settings, PXP > > > handshake, ... > > > > > > In conclusion: it can't be ensured that one register belongs to one > > > dedicated IP and the LDB is rather an exception than the rule. > > > > It is fine if there's a child node for LDB if the LDB registers are > > consistent, but the other misc things are represented by the parent > > node. It is certainly not a requirement that either everything be in > > child nodes or nothing be in child nodes. > > > > What I don't see in this series is what problem does this fix? If you > > are going to break compatibility, then there had better be a good > > reason. > > Hi Rob, > > with the upcoming i.MX9x SoCs the parent syscon (BLKCTRL) controlls > multiple other IPs, e.g. a DPI mux added by commit 3feaa4342637 > ("dt-bindings: soc: imx93-media-blk-ctrl: Add PDFC subnode to schema and > example"). > > During the discussion of the above commit we agreed that the sub-devices > of the syscon shall not use the reg property due to the fact that one > register serves multiple purposes. In the above case the same register > controlling the dpi-mux also controlls MIPI-DSI bits. The MIPI-DSI bits > can be abstracted as drm-bridge as well. Two sub-devs using the same > 'reg' property below the same parent seems odd and I don't know if this > allowed either. The MIPI-DSI bits are not modelled as sub-devs, but instead, according to fsl,imx93-mipi-dsi.yaml[1], an i.MX93 MIPI DSI driver would access the bits directly through the syscon. Here, dpi-mux is a sub-dev while the MIPI-DSI bits are "misc things represented by the parent node"(Rob's words). I don't see any problem here at least for Linux since regmap provides register access synchronization if everyone accesses registers through parent node's regmap. [1] https://elixir.bootlin.com/linux/v7.0/source/Documentation/devicetree/bindings/display/bridge/fsl,imx93-mipi-dsi.yaml#L43-L47 -- Regards, Liu Ying