Re: [PATCH] staging: sm750fb: add const to g_fbmode array
From: kernel test robot
Date: Sat May 23 2026 - 17:28:07 EST
Hi Diego,
kernel test robot noticed the following build errors:
[auto build test ERROR on staging/staging-testing]
url: https://github.com/intel-lab-lkp/linux/commits/Diego-Fernando-Mancera-G-mez/staging-sm750fb-add-const-to-g_fbmode-array/20260522-050816
base: staging/staging-testing
patch link: https://lore.kernel.org/r/20260521210523.133725-2-diegomancera.dev%40gmail.com
patch subject: [PATCH] staging: sm750fb: add const to g_fbmode array
config: loongarch-allmodconfig (https://download.01.org/0day-ci/archive/20260524/202605240543.MkxvjE7m-lkp@xxxxxxxxx/config)
compiler: clang version 19.1.7 (https://github.com/llvm/llvm-project cd708029e0b2869e80abe31ddb175f7c35361f90)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260524/202605240543.MkxvjE7m-lkp@xxxxxxxxx/reproduce)
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
| Reported-by: kernel test robot <lkp@xxxxxxxxx>
| Closes: https://lore.kernel.org/oe-kbuild-all/202605240543.MkxvjE7m-lkp@xxxxxxxxx/
All errors (new ones prefixed by >>):
>> drivers/staging/sm750fb/sm750.c:773:19: error: cannot assign to variable 'g_fbmode' with const-qualified type 'const char *const[2]'
773 | g_fbmode[index] = g_def_fbmode;
| ~~~~~~~~~~~~~~~ ^
drivers/staging/sm750fb/sm750.c:24:27: note: variable 'g_fbmode' declared const here
24 | static const char * const g_fbmode[] = {NULL, NULL};
| ~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
drivers/staging/sm750fb/sm750.c:775:20: error: cannot assign to variable 'g_fbmode' with const-qualified type 'const char *const[2]'
775 | g_fbmode[index] = g_fbmode[0];
| ~~~~~~~~~~~~~~~ ^
drivers/staging/sm750fb/sm750.c:24:27: note: variable 'g_fbmode' declared const here
24 | static const char * const g_fbmode[] = {NULL, NULL};
| ~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
drivers/staging/sm750fb/sm750.c:884:17: error: cannot assign to variable 'g_fbmode' with const-qualified type 'const char *const[2]'
884 | g_fbmode[0] = opt;
| ~~~~~~~~~~~ ^
drivers/staging/sm750fb/sm750.c:24:27: note: variable 'g_fbmode' declared const here
24 | static const char * const g_fbmode[] = {NULL, NULL};
| ~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
drivers/staging/sm750fb/sm750.c:888:17: error: cannot assign to variable 'g_fbmode' with const-qualified type 'const char *const[2]'
888 | g_fbmode[1] = opt;
| ~~~~~~~~~~~ ^
drivers/staging/sm750fb/sm750.c:24:27: note: variable 'g_fbmode' declared const here
24 | static const char * const g_fbmode[] = {NULL, NULL};
| ~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
4 errors generated.
vim +773 drivers/staging/sm750fb/sm750.c
81dee67e215b23f Sudip Mukherjee 2015-03-03 707
81dee67e215b23f Sudip Mukherjee 2015-03-03 708 static int lynxfb_set_fbinfo(struct fb_info *info, int index)
81dee67e215b23f Sudip Mukherjee 2015-03-03 709 {
81dee67e215b23f Sudip Mukherjee 2015-03-03 710 int i;
81dee67e215b23f Sudip Mukherjee 2015-03-03 711 struct lynxfb_par *par;
e359b6a863e19f2 Mike Rapoport 2015-10-26 712 struct sm750_dev *sm750_dev;
81dee67e215b23f Sudip Mukherjee 2015-03-03 713 struct lynxfb_crtc *crtc;
81dee67e215b23f Sudip Mukherjee 2015-03-03 714 struct lynxfb_output *output;
81dee67e215b23f Sudip Mukherjee 2015-03-03 715 struct fb_var_screeninfo *var;
81dee67e215b23f Sudip Mukherjee 2015-03-03 716 struct fb_fix_screeninfo *fix;
81dee67e215b23f Sudip Mukherjee 2015-03-03 717
81dee67e215b23f Sudip Mukherjee 2015-03-03 718 const struct fb_videomode *pdb[] = {
81dee67e215b23f Sudip Mukherjee 2015-03-03 719 lynx750_ext, NULL, vesa_modes,
81dee67e215b23f Sudip Mukherjee 2015-03-03 720 };
81dee67e215b23f Sudip Mukherjee 2015-03-03 721 int cdb[] = {ARRAY_SIZE(lynx750_ext), 0, VESA_MODEDB_SIZE};
d0856045f0e9fc9 Hungyu Lin 2026-04-01 722 static const char * const fix_id[2] = {
81dee67e215b23f Sudip Mukherjee 2015-03-03 723 "sm750_fb1", "sm750_fb2",
81dee67e215b23f Sudip Mukherjee 2015-03-03 724 };
81dee67e215b23f Sudip Mukherjee 2015-03-03 725
81dee67e215b23f Sudip Mukherjee 2015-03-03 726 int ret, line_length;
81dee67e215b23f Sudip Mukherjee 2015-03-03 727
81dee67e215b23f Sudip Mukherjee 2015-03-03 728 ret = 0;
81dee67e215b23f Sudip Mukherjee 2015-03-03 729 par = (struct lynxfb_par *)info->par;
e359b6a863e19f2 Mike Rapoport 2015-10-26 730 sm750_dev = par->dev;
81dee67e215b23f Sudip Mukherjee 2015-03-03 731 crtc = &par->crtc;
81dee67e215b23f Sudip Mukherjee 2015-03-03 732 output = &par->output;
81dee67e215b23f Sudip Mukherjee 2015-03-03 733 var = &info->var;
81dee67e215b23f Sudip Mukherjee 2015-03-03 734 fix = &info->fix;
81dee67e215b23f Sudip Mukherjee 2015-03-03 735
81dee67e215b23f Sudip Mukherjee 2015-03-03 736 /* set index */
81dee67e215b23f Sudip Mukherjee 2015-03-03 737 par->index = index;
81dee67e215b23f Sudip Mukherjee 2015-03-03 738 output->channel = &crtc->channel;
81dee67e215b23f Sudip Mukherjee 2015-03-03 739 sm750fb_set_drv(par);
81dee67e215b23f Sudip Mukherjee 2015-03-03 740
d11ac7cbcc266c6 Sudip Mukherjee 2015-08-07 741 /*
d11ac7cbcc266c6 Sudip Mukherjee 2015-08-07 742 * set current cursor variable and proc pointer,
d11ac7cbcc266c6 Sudip Mukherjee 2015-08-07 743 * must be set after crtc member initialized
d11ac7cbcc266c6 Sudip Mukherjee 2015-08-07 744 */
fdc234d85210d91 Benjamin Philip 2021-07-28 745 crtc->cursor.offset = crtc->o_screen + crtc->vidmem_size - 1024;
e359b6a863e19f2 Mike Rapoport 2015-10-26 746 crtc->cursor.mmio = sm750_dev->pvReg +
e359b6a863e19f2 Mike Rapoport 2015-10-26 747 0x800f0 + (int)crtc->channel * 0x140;
81dee67e215b23f Sudip Mukherjee 2015-03-03 748
cd33da26036ea54 Christopher Carbone 2022-08-23 749 crtc->cursor.max_h = 64;
cd33da26036ea54 Christopher Carbone 2022-08-23 750 crtc->cursor.max_w = 64;
39f9137268ee3df Benjamin Philip 2021-07-26 751 crtc->cursor.size = crtc->cursor.max_h * crtc->cursor.max_w * 2 / 8;
f50b4602fea62fe Jennifer Guo 2026-05-09 752 crtc->cursor.vstart = sm750_dev->vmem + crtc->cursor.offset;
81dee67e215b23f Sudip Mukherjee 2015-03-03 753
3de08a2d14ff8c7 Lorenzo Stoakes 2015-03-20 754 memset_io(crtc->cursor.vstart, 0, crtc->cursor.size);
f7c8a046577e09d Thomas Zimmermann 2023-11-27 755 if (!g_hwcursor)
52d0744d751d8f1 Arnd Bergmann 2016-11-09 756 sm750_hw_cursor_disable(&crtc->cursor);
81dee67e215b23f Sudip Mukherjee 2015-03-03 757
81dee67e215b23f Sudip Mukherjee 2015-03-03 758 /* set info->fbops, must be set before fb_find_mode */
e359b6a863e19f2 Mike Rapoport 2015-10-26 759 if (!sm750_dev->accel_off) {
81dee67e215b23f Sudip Mukherjee 2015-03-03 760 /* use 2d acceleration */
f7c8a046577e09d Thomas Zimmermann 2023-11-27 761 if (!g_hwcursor)
f7c8a046577e09d Thomas Zimmermann 2023-11-27 762 info->fbops = &lynxfb_ops_accel;
f7c8a046577e09d Thomas Zimmermann 2023-11-27 763 else
f7c8a046577e09d Thomas Zimmermann 2023-11-27 764 info->fbops = &lynxfb_ops_accel_with_cursor;
f7c8a046577e09d Thomas Zimmermann 2023-11-27 765 } else {
f7c8a046577e09d Thomas Zimmermann 2023-11-27 766 if (!g_hwcursor)
81dee67e215b23f Sudip Mukherjee 2015-03-03 767 info->fbops = &lynxfb_ops;
f7c8a046577e09d Thomas Zimmermann 2023-11-27 768 else
f7c8a046577e09d Thomas Zimmermann 2023-11-27 769 info->fbops = &lynxfb_ops_with_cursor;
f7c8a046577e09d Thomas Zimmermann 2023-11-27 770 }
81dee67e215b23f Sudip Mukherjee 2015-03-03 771
81dee67e215b23f Sudip Mukherjee 2015-03-03 772 if (!g_fbmode[index]) {
81dee67e215b23f Sudip Mukherjee 2015-03-03 @773 g_fbmode[index] = g_def_fbmode;
81dee67e215b23f Sudip Mukherjee 2015-03-03 774 if (index)
81dee67e215b23f Sudip Mukherjee 2015-03-03 775 g_fbmode[index] = g_fbmode[0];
81dee67e215b23f Sudip Mukherjee 2015-03-03 776 }
81dee67e215b23f Sudip Mukherjee 2015-03-03 777
81dee67e215b23f Sudip Mukherjee 2015-03-03 778 for (i = 0; i < 3; i++) {
81dee67e215b23f Sudip Mukherjee 2015-03-03 779 ret = fb_find_mode(var, info, g_fbmode[index],
81dee67e215b23f Sudip Mukherjee 2015-03-03 780 pdb[i], cdb[i], NULL, 8);
81dee67e215b23f Sudip Mukherjee 2015-03-03 781
db7fb3588ab4920 Artem Lytkin 2026-02-23 782 if (ret == 1 || ret == 2)
81dee67e215b23f Sudip Mukherjee 2015-03-03 783 break;
81dee67e215b23f Sudip Mukherjee 2015-03-03 784 }
81dee67e215b23f Sudip Mukherjee 2015-03-03 785
81dee67e215b23f Sudip Mukherjee 2015-03-03 786 /* set par */
81dee67e215b23f Sudip Mukherjee 2015-03-03 787 par->info = info;
81dee67e215b23f Sudip Mukherjee 2015-03-03 788
81dee67e215b23f Sudip Mukherjee 2015-03-03 789 /* set info */
e3a3f9f5123683b Mike Rapoport 2015-10-26 790 line_length = ALIGN((var->xres_virtual * var->bits_per_pixel / 8),
e3a3f9f5123683b Mike Rapoport 2015-10-26 791 crtc->line_pad);
81dee67e215b23f Sudip Mukherjee 2015-03-03 792
81dee67e215b23f Sudip Mukherjee 2015-03-03 793 info->pseudo_palette = &par->pseudo_palette[0];
cc59bde1c920ab6 Benjamin Philip 2021-07-28 794 info->screen_base = crtc->v_screen;
81dee67e215b23f Sudip Mukherjee 2015-03-03 795 info->screen_size = line_length * var->yres_virtual;
81dee67e215b23f Sudip Mukherjee 2015-03-03 796
81dee67e215b23f Sudip Mukherjee 2015-03-03 797 /* set info->fix */
81dee67e215b23f Sudip Mukherjee 2015-03-03 798 fix->type = FB_TYPE_PACKED_PIXELS;
81dee67e215b23f Sudip Mukherjee 2015-03-03 799 fix->type_aux = 0;
81dee67e215b23f Sudip Mukherjee 2015-03-03 800 fix->xpanstep = crtc->xpanstep;
81dee67e215b23f Sudip Mukherjee 2015-03-03 801 fix->ypanstep = crtc->ypanstep;
81dee67e215b23f Sudip Mukherjee 2015-03-03 802 fix->ywrapstep = crtc->ywrapstep;
81dee67e215b23f Sudip Mukherjee 2015-03-03 803 fix->accel = FB_ACCEL_SMI;
81dee67e215b23f Sudip Mukherjee 2015-03-03 804
8c475735085a7db Tim Wassink 2025-12-21 805 strscpy(fix->id, fix_id[index], sizeof(fix->id));
81dee67e215b23f Sudip Mukherjee 2015-03-03 806
fdc234d85210d91 Benjamin Philip 2021-07-28 807 fix->smem_start = crtc->o_screen + sm750_dev->vidmem_start;
d11ac7cbcc266c6 Sudip Mukherjee 2015-08-07 808 /*
d11ac7cbcc266c6 Sudip Mukherjee 2015-08-07 809 * according to mmap experiment from user space application,
81dee67e215b23f Sudip Mukherjee 2015-03-03 810 * fix->mmio_len should not larger than virtual size
81dee67e215b23f Sudip Mukherjee 2015-03-03 811 * (xres_virtual x yres_virtual x ByPP)
81dee67e215b23f Sudip Mukherjee 2015-03-03 812 * Below line maybe buggy when user mmap fb dev node and write
81dee67e215b23f Sudip Mukherjee 2015-03-03 813 * data into the bound over virtual size
d11ac7cbcc266c6 Sudip Mukherjee 2015-08-07 814 */
81dee67e215b23f Sudip Mukherjee 2015-03-03 815 fix->smem_len = crtc->vidmem_size;
81dee67e215b23f Sudip Mukherjee 2015-03-03 816 info->screen_size = fix->smem_len;
81dee67e215b23f Sudip Mukherjee 2015-03-03 817 fix->line_length = line_length;
e359b6a863e19f2 Mike Rapoport 2015-10-26 818 fix->mmio_start = sm750_dev->vidreg_start;
e359b6a863e19f2 Mike Rapoport 2015-10-26 819 fix->mmio_len = sm750_dev->vidreg_size;
b610e1193a917f4 Matej Dujava 2020-04-30 820
b610e1193a917f4 Matej Dujava 2020-04-30 821 lynxfb_set_visual_mode(info);
81dee67e215b23f Sudip Mukherjee 2015-03-03 822
81dee67e215b23f Sudip Mukherjee 2015-03-03 823 /* set var */
81dee67e215b23f Sudip Mukherjee 2015-03-03 824 var->activate = FB_ACTIVATE_NOW;
81dee67e215b23f Sudip Mukherjee 2015-03-03 825 var->accel_flags = 0;
81dee67e215b23f Sudip Mukherjee 2015-03-03 826 var->vmode = FB_VMODE_NONINTERLACED;
81dee67e215b23f Sudip Mukherjee 2015-03-03 827
61c507cf652da1b Michel von Czettritz 2015-03-26 828 ret = fb_alloc_cmap(&info->cmap, 256, 0);
61c507cf652da1b Michel von Czettritz 2015-03-26 829 if (ret < 0) {
fbab250eb51d6d6 Artem Lytkin 2026-02-07 830 dev_err(info->device, "Could not allocate memory for cmap.\n");
81dee67e215b23f Sudip Mukherjee 2015-03-03 831 goto exit;
81dee67e215b23f Sudip Mukherjee 2015-03-03 832 }
81dee67e215b23f Sudip Mukherjee 2015-03-03 833
81dee67e215b23f Sudip Mukherjee 2015-03-03 834 exit:
81dee67e215b23f Sudip Mukherjee 2015-03-03 835 lynxfb_ops_check_var(var, info);
81dee67e215b23f Sudip Mukherjee 2015-03-03 836 return ret;
81dee67e215b23f Sudip Mukherjee 2015-03-03 837 }
81dee67e215b23f Sudip Mukherjee 2015-03-03 838
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki