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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?urr4Qp67w9PiVslpSyHO4P54aP+ClSYjz/vI1gWq2N5AwYavTRpLsDBM1DGh?= =?us-ascii?Q?eNMDrZoYZu7M4TGeQKy4QmiANZ90AFymWV2VbKQ1oHl32JKBBPlABBuSDjhz?= =?us-ascii?Q?q6aPLCLj74jsCMWT0iqt2GXLu7c8zKS0W+aeB84fAwyURbbiuBpc/n3a/4B0?= =?us-ascii?Q?59hcdfTojMjxnZb+392dkRgan0UxXsP3WBU1HHP1Zcfma9IDd/o/9eM2IJKV?= =?us-ascii?Q?haTmi4I5gWO4TpGYpzfG+XRq5t4Gvobean26Mfat4IDUu66FA9pJ7B9XIDdh?= =?us-ascii?Q?F2TCJleKUaFF4W7S9Qj17DJM3VP21S6y6Wf4rYbFPpOjd9PWzdN0Ve74bq05?= =?us-ascii?Q?33VwHXkNDzFZiEx/xD9O+lPEzs6jj3TJXbzl+3U/i5s91VsJDV7j0PcgbCX3?= =?us-ascii?Q?u7NhWRPVJwk6ekfrzm6ozLGZS01aE9NX6dubIFQIXL4yfNTn39j2gm5LodI2?= =?us-ascii?Q?8pSANbyI5irqrCifJPPHoymcReL67BshGK+wWIh/Rb1KaCFtgzX+2gk3hDZc?= =?us-ascii?Q?ywv+2uO4i3AkGDm8J830MBkmr0uPmiNZrwHgY9NZ1ne6nm5YSYWsb0q6x6fj?= =?us-ascii?Q?Z/tUbyHALf/YC1i9B73h7Hx0dAcNpRLa4WTmNPeT3TIMX/dCwSuOFo1ebMzK?= =?us-ascii?Q?ogf4znMaXDYsNcPYWrTogR3xUflDMs4k8hcowtBsGVpEsPyO8kWU4a8se6F8?= =?us-ascii?Q?KKUWxkpRzwJM0Z0+LfDi7GIcskv8F5NwjWAgGiaxuXQvqTpAzGa0i38yYVXw?= =?us-ascii?Q?+ArPGrVOV2Z6w1Oq8Vw17rD3ZSiCRQ0Jp/A6+IJCofE8nWg2EgJXDfk9zkbu?= =?us-ascii?Q?CbaSW+6I14SmK+KBVBuzhnY0PzJSCUlg5aL29ue9V3dx479MWN6oTOq+8Cad?= =?us-ascii?Q?UGknsOUSEBlU8ApKlvlSSCRn+UgQOnGThAypfXbWI1QeGPDXQBx+2myjWFZH?= =?us-ascii?Q?DEqfnxLD28v8QTesOtSrE1WAPeOssvotge7+ksID8uLSaoLnuPsjY56lhAR0?= =?us-ascii?Q?2PguNMC6Xxyf3g4JPUghCa5fIBWw+kOepq1MQitGRzp0jHwuY7/U3b8zWtJU?= =?us-ascii?Q?QAZt3WsoJLnGicllp+XLiqf59cQL0CYhE92ZTekBscPQFreUv+Thf0WygKag?= =?us-ascii?Q?uLFrRgNkI6f4b2E4KwnlW2J9ybsONqnxof6HDxNra/I6SCqKEYddAwH6LVjw?= =?us-ascii?Q?N1hTyk6y9+2N0qp1GyS/fLwAQ25gzIvQb6IL4Cg9/07bHxPDDNQ1hGjjwT7P?= =?us-ascii?Q?eR1lyW8+oEMrUirlmzf1QqDYII75tLvmiT0vU4hskiIjo0BpsRkE266YnNsj?= =?us-ascii?Q?67i7jxFow1vsWmpRSdqVtYqgM34RH5XjrT9pjQy4kVLzfPH0Vp8enKCbYm82?= =?us-ascii?Q?gsoSdPQbQUGM38pjbXtZp2MoWljYeeEFAK3TYKMSB2OOnCZzVEiYGwL/DDxh?= =?us-ascii?Q?phcNgaS4FAjWnCneAcrRRG7sNofmv6+X3VvZRR27XsRDiKdSweFQVFXP7Vw4?= =?us-ascii?Q?Y9GAgSXMBM2jJL6dkcIz5SXay7WZjxke6D7CGI5uc/9Wh4N0O+3L3AtRxBcO?= =?us-ascii?Q?mCQOK3PYWj+ZyK2XIcOTkkXPG8LHIEM9Ska1RpvmzLgqd0Uqi8OGk4NXswmA?= =?us-ascii?Q?Yd6za64vNQV36g2h7r1vuJ74n0v1o55Wh9GyTQZ51hZ4ld2uPvR8t/MNbRAC?= =?us-ascii?Q?PfvwQup3Dq8I47no0byK8bIncYNfe1SpxFsDTV36DD+lA9HQ?= X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: 59f660a2-bc26-4694-cdd0-08de7de808be X-MS-Exchange-CrossTenant-AuthSource: PA4PR04MB9366.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 09 Mar 2026 14:27:46.7514 (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: VsUxKVTQEaDQi1PxuV5UxIYDdslZcKTVZLeizfSzwLg2POMwFQosbdzoeqqDBPBa2hsn2OT1dcoF3iMTAkUyMw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PA1PR04MB10795 On Mon, Mar 09, 2026 at 12:24:33PM +0100, Vinod Koul wrote: > On 14-01-26, 12:12, Frank Li wrote: > > Many DMA engine drivers store a dma_slave_config per channel. Propagate > > this configuration into struct dma_chan to avoid duplicating the same > > code in each driver. > > > > Much of dma_slave_config is identical for source and destination. Split > > the configuration into src and dst groups and use a union to preserve > > backward compatibility. This reduces the need for drivers to repeatedly > > check the DMA transfer direction. > > The reason why we had both the src/dstn sides was intended method to > allow upport ofr device to device dma. Some interest was shown for that > at that time. > I dont think we have such a user even now... My means is the field name is identical, not value identical although most case is the identical. but it is possible, especial FIFO space windows, sound/soc/fsl/fsl_asrc_dma.c use DEV_TO_DEV, at least src and addr use differece address. Frank > > > -- > ~Vinod