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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?C2eMHHcM2HxdR9/ASkkviwAyB3L3o54rTH/iQtdnNM4lWDJJXMtf0zjJtDuj?= =?us-ascii?Q?FkhxEIXssWoFQkjYjafZNDlAh2RbV5GFoiZzdB7LL2fypHMPEnspHtMbAHNd?= =?us-ascii?Q?BKbjapRegSK6AUnP5MIkIJUCmhgStkWH8si3DNnm90mCjnL6zm7BBsm740Kt?= =?us-ascii?Q?X4WrV5ttjzeK1DduPqsAkN846ng1ChmJ9PU/19/S+Yvf5scpymLl44fI751w?= =?us-ascii?Q?AiEpLcQCs0CAHIBPLhqyBEEc5tpko6YJgl6mz9aSpfvOPYkN9SB+3SgkX+5j?= =?us-ascii?Q?l2vfb8FfNiPnBZiYwd0oMMsdPRQYFfOZAyNX4TXlxiPuKvBJAjumf7dim9DO?= =?us-ascii?Q?H0r+Q1CDSXC1tW+uHkzOlE74igb+DoBftQI+GtYGNNHrzSjGr1zDB0Rccmep?= =?us-ascii?Q?4+cILX1ygN3Osk6Hj69N7FcvpVjYphCotbaahb7DkuF2Nf0InoGsZRr4DgMP?= =?us-ascii?Q?JaY4dkng7pXI5Sh0fTaS2HQWLKJ4YmRX5AUY2Y1HbckDQxVSplji7vSkW87g?= =?us-ascii?Q?dXLVmR0uTq2OigWBVd+Dp47NhHFxyoDspg/mcV09Cb6l9NZmDFBks/W2Xrii?= =?us-ascii?Q?MIQSlw8hHP2Syha8U/b8+LxuErPbf8XabtrIAqWtJeCbXw1kvxhwlIZdPie7?= =?us-ascii?Q?qeIWPTD9eGUXRha0MDCbcQtWNoFmlSrZv6YiWb4V2IuZbw1pxOfy0DCXzpci?= =?us-ascii?Q?+uOKgRu/q/RMj4PoqJ3i0KZMkmjiF6S1E1lptn1DF85snzsds1Uh/auHkTAd?= =?us-ascii?Q?46qxIik/uyh81JJ1Hs7lpglK18icVFUJZGRwo+5wz1NI1t9N42inlmtmAw20?= =?us-ascii?Q?RKbs870FCSFO0uBG2iSIW4ddUeD2IaptZVg1DlQRIAtUaqVrEdtvDO3uULFH?= =?us-ascii?Q?29ODbhjcREF5tTCPqzT5Ye1k1qaNaNwc8XJrbqD1Dvsac5vMpUu86UeZWlLz?= =?us-ascii?Q?QuAm2x3USYQIVlbWQK+NZKQWG8REFQCt7o/vwAKAE0hliSrf0oarfc7pO04l?= =?us-ascii?Q?6so+fx8Gp0JtPtJ5INJ4y7kveeE6UqBdJxJJAAh+z/6GZkYs/eo3oCSp3cJ0?= =?us-ascii?Q?MV0bYhcUkKwAeVHsz401LEbcx1MzwSzRj2rSblWbZJqxhPyH2ml6+5nmgrLc?= =?us-ascii?Q?+x7R7JhyBlsgRZZocppNcEKQbxbFROdOFnmrcy437gPG4CKJduejjqSkI3K+?= =?us-ascii?Q?tpLeUU1FFDn2IkBCCnFa9CAahM7Fr/qexV+Eiz2+l+YOoJJddDaxxlPvNCDN?= =?us-ascii?Q?Fr4SzNcJ09fPDHPpJvn0tKWuo8YSrOLhuDo70xBMiNG7hpCmocAxeIej1tbF?= =?us-ascii?Q?hG7mNBL2GrxieLTE0BjPZbYty/sohOeRSYBQHer2zsXNpSVLNUlk74O9K32E?= =?us-ascii?Q?mkVQxVSysTBYsh6pgIZqjTvH2hJmg3lZkzBmpFhETqpP2zYZhNqoL2yNArif?= =?us-ascii?Q?IP4Z09PvM+YcDyysqcHDtvN0xbOS6no5OBZ5jDVjk+sFAw5vf9Z5xh3Fqz42?= =?us-ascii?Q?t5pDM0x02sSrp4BR6xa+eMBpHtwi2sgGDBgHIpt0kkAPuxH1Mstv6s0UqmRv?= =?us-ascii?Q?qoypqGCw5PQpli+K0PQ8yNAP68MvkFPWDMXqQoYI?= X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: 38aff08a-365e-403b-8fb8-08de2919c59d X-MS-Exchange-CrossTenant-AuthSource: DU2PR04MB8951.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 21 Nov 2025 16:19:40.2404 (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: TUwYfjUoNMYmIVam/EVGSw+v5NWjjKzu9OSYWFFK8ne9ycNBixn4Qq6TbTAwkwwjYSPNoUyS4bwOOO7QXqgX+Q== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DU6PR04MB11133 On Mon, Nov 17, 2025 at 11:03:55AM +0800, carlos.song@nxp.com wrote: > From: Carlos Song > > 't->len' is an unsigned integer, while 'watermark' and 'txfifosize' are > u8. Using min_t with typeof(watermark) forces both values to be cast to > u8, which truncates len when it exceeds 255. For example, len = 4096 > becomes 0 after casting, resulting in an incorrect watermark value. > > Use a wider type in min_t to avoid truncation and ensure the correct > minimum value is applied. > > Fixes: a750050349ea ("spi: spi-fsl-lpspi: use min_t() to improve code") > Signed-off-by: Carlos Song > --- > drivers/spi/spi-fsl-lpspi.c | 8 +++++++- > 1 file changed, 7 insertions(+), 1 deletion(-) > > diff --git a/drivers/spi/spi-fsl-lpspi.c b/drivers/spi/spi-fsl-lpspi.c > index 8da66e101386..065456aba2ae 100644 > --- a/drivers/spi/spi-fsl-lpspi.c > +++ b/drivers/spi/spi-fsl-lpspi.c > @@ -486,7 +486,13 @@ static int fsl_lpspi_setup_transfer(struct spi_controller *controller, > fsl_lpspi->tx = fsl_lpspi_buf_tx_u32; > } > > - fsl_lpspi->watermark = min_t(typeof(fsl_lpspi->watermark), > + /* > + * t->len is 'unsigned' and txfifosize and watermrk is 'u8', force > + * type cast is inevitable. When len > 255, len will be truncated in min_t(), > + * it caused wrong watermark set. 'unsigned int' is as the designated type > + * for min_t() to avoid truncation. > + */ > + fsl_lpspi->watermark = min_t(unsigned int, > fsl_lpspi->txfifosize, > t->len); There are thread discussion about min() and mit_t() https://lore.kernel.org/all/20251119224140.8616-1-david.laight.linux@gmail.com/ Frank > > -- > 2.34.1 >