drivers/gpu/drm/panel/panel-himax-hx8279.c:807 hx8279_check_gmux_config() warn: impossible condition '(gmux->gout_r[i] > ((((0) + (((((1 << (8 * 4 - 1 - (((-1)) < 1))) - 1) + (1 << (8 * 4 - 1 - (((-1)) < 1))))) << (6) & ((((1 << (8 * 4 - 1 - (((-1)) < 1))...

BCC: [email protected]
CC: [email protected]
CC: [email protected]
TO: Vincent Mailhol <[email protected]>
CC: Yury Norov <[email protected]>

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   4539944e515183668109bdf4d0c3d7d228383d88
commit: 104ea1c84b91c9f452e497ba51602b903711cdd5 bits: unify the non-asm GENMASK*()
date:   12 months ago
:::::: branch date: 2 days ago
:::::: commit date: 12 months ago
config: riscv-randconfig-r071-20260723 (https://download.01.org/0day-ci/archive/20260725/[email protected]/config)
compiler: clang version 24.0.0git (https://github.com/llvm/llvm-project 890b11e09e45e9d8b29f2f94f22052be3934e757)
smatch: v0.5.0-9187-g5189e3fb

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Fixes: 104ea1c84b91 ("bits: unify the non-asm GENMASK*()")
| Reported-by: kernel test robot <[email protected]>
| Reported-by: Dan Carpenter <[email protected]>
| Closes: https://lore.kernel.org/r/[email protected]/

New smatch warnings:
drivers/gpu/drm/panel/panel-himax-hx8279.c:807 hx8279_check_gmux_config() warn: impossible condition '(gmux->gout_r[i] > ((((0) + (((((1 << (8 * 4 - 1 - (((-1)) < 1))) - 1) + (1 << (8 * 4 - 1 - (((-1)) < 1))))) << (6) & ((((1 << (8 * 4 - 1 - (((-1)) < 1))) - 1) + (1 << (8 * 4 - 1 - (((-1)) < 1))))) >> ((4 * 8) - 1 - (7))))) | (((0) + (((((1 << (8 * 4 - 1 - (((-1)) < 1))) - 1) + (1 << (8 * 4 - 1 - (((-1)) < 1))))) << (0) & ((((1 << (8 * 4 - 1 - (((-1)) < 1))) - 1) + (1 << (8 * 4 - 1 - (((-1)) < 1))))) >> ((4 * 8) - 1 - (5))))))) => (0-255 > 255)'

Old smatch warnings:
drivers/gpu/drm/panel/panel-himax-hx8279.c:801 hx8279_check_gmux_config() warn: impossible condition '(gmux->gout_l[i] > ((((0) + (((((1 << (8 * 4 - 1 - (((-1)) < 1))) - 1) + (1 << (8 * 4 - 1 - (((-1)) < 1))))) << (6) & ((((1 << (8 * 4 - 1 - (((-1)) < 1))) - 1) + (1 << (8 * 4 - 1 - (((-1)) < 1))))) >> ((4 * 8) - 1 - (7))))) | (((0) + (((((1 << (8 * 4 - 1 - (((-1)) < 1))) - 1) + (1 << (8 * 4 - 1 - (((-1)) < 1))))) << (0) & ((((1 << (8 * 4 - 1 - (((-1)) < 1))) - 1) + (1 << (8 * 4 - 1 - (((-1)) < 1))))) >> ((4 * 8) - 1 - (5))))))) => (0-255 > 255)'

vim +807 drivers/gpu/drm/panel/panel-himax-hx8279.c

38d42c26138998 AngeloGioacchino Del Regno 2025-04-14  789  
38d42c26138998 AngeloGioacchino Del Regno 2025-04-14  790  static int hx8279_check_gmux_config(struct hx8279 *hx, struct device *dev)
38d42c26138998 AngeloGioacchino Del Regno 2025-04-14  791  {
38d42c26138998 AngeloGioacchino Del Regno 2025-04-14  792  	const struct hx8279_panel_desc *desc = hx->desc;
38d42c26138998 AngeloGioacchino Del Regno 2025-04-14  793  	const struct hx8279_goa_mux *gmux = desc->gmux;
38d42c26138998 AngeloGioacchino Del Regno 2025-04-14  794  	int i;
38d42c26138998 AngeloGioacchino Del Regno 2025-04-14  795  
38d42c26138998 AngeloGioacchino Del Regno 2025-04-14  796  	/* No gmux defined means we simply skip the GOA mux configuration */
38d42c26138998 AngeloGioacchino Del Regno 2025-04-14  797  	if (!gmux)
38d42c26138998 AngeloGioacchino Del Regno 2025-04-14  798  		return 0;
38d42c26138998 AngeloGioacchino Del Regno 2025-04-14  799  
38d42c26138998 AngeloGioacchino Del Regno 2025-04-14  800  	for (i = 0; i < ARRAY_SIZE(gmux->gout_l); i++) {
38d42c26138998 AngeloGioacchino Del Regno 2025-04-14  801  		if (gmux->gout_l[i] > (HX8279_GOUT_STB | HX8279_GOUT_SEL))
38d42c26138998 AngeloGioacchino Del Regno 2025-04-14  802  			return dev_err_probe(dev, -EINVAL,
38d42c26138998 AngeloGioacchino Del Regno 2025-04-14  803  					     "Invalid value found in gout_l[%d]\n", i);
38d42c26138998 AngeloGioacchino Del Regno 2025-04-14  804  	}
38d42c26138998 AngeloGioacchino Del Regno 2025-04-14  805  
38d42c26138998 AngeloGioacchino Del Regno 2025-04-14  806  	for (i = 0; i < ARRAY_SIZE(gmux->gout_r); i++) {
38d42c26138998 AngeloGioacchino Del Regno 2025-04-14 @807  		if (gmux->gout_r[i] > (HX8279_GOUT_STB | HX8279_GOUT_SEL))
38d42c26138998 AngeloGioacchino Del Regno 2025-04-14  808  			return dev_err_probe(dev, -EINVAL,
38d42c26138998 AngeloGioacchino Del Regno 2025-04-14  809  					     "Invalid value found in gout_r[%d]\n", i);
38d42c26138998 AngeloGioacchino Del Regno 2025-04-14  810  	}
38d42c26138998 AngeloGioacchino Del Regno 2025-04-14  811  
38d42c26138998 AngeloGioacchino Del Regno 2025-04-14  812  	return 0;
38d42c26138998 AngeloGioacchino Del Regno 2025-04-14  813  }
38d42c26138998 AngeloGioacchino Del Regno 2025-04-14  814  

:::::: The code at line 807 was first introduced by commit
:::::: 38d42c261389985e8dd4739dbd97e2dc855e8dd0 drm: panel: Add driver for Himax HX8279 DDIC panels

:::::: TO: AngeloGioacchino Del Regno <[email protected]>
:::::: CC: Neil Armstrong <[email protected]>

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