Re: [PATCH] staging: sm750fb: add missing const qualifier to char pointer array
From: kernel test robot
Date: Sat Mar 07 2026 - 20:47:20 EST
Hi Oskar,
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/Oskar-Ray-Frayssinet/staging-sm750fb-add-missing-const-qualifier-to-char-pointer-array/20260307-212030
base: staging/staging-testing
patch link: https://lore.kernel.org/r/20260307131833.1138-1-rayfraytech%40gmail.com
patch subject: [PATCH] staging: sm750fb: add missing const qualifier to char pointer array
config: i386-buildonly-randconfig-003-20260308 (https://download.01.org/0day-ci/archive/20260308/202603080944.rMPCAhoj-lkp@xxxxxxxxx/config)
compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260308/202603080944.rMPCAhoj-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/202603080944.rMPCAhoj-lkp@xxxxxxxxx/
All errors (new ones prefixed by >>):
>> drivers/staging/sm750fb/sm750.c:782:19: error: cannot assign to variable 'g_fbmode' with const-qualified type 'const char *const[2]'
782 | g_fbmode[index] = g_def_fbmode;
| ~~~~~~~~~~~~~~~ ^
drivers/staging/sm750fb/sm750.c:36:27: note: variable 'g_fbmode' declared const here
36 | static const char * const g_fbmode[] = {NULL, NULL};
| ~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
drivers/staging/sm750fb/sm750.c:784:20: error: cannot assign to variable 'g_fbmode' with const-qualified type 'const char *const[2]'
784 | g_fbmode[index] = g_fbmode[0];
| ~~~~~~~~~~~~~~~ ^
drivers/staging/sm750fb/sm750.c:36:27: note: variable 'g_fbmode' declared const here
36 | static const char * const g_fbmode[] = {NULL, NULL};
| ~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
drivers/staging/sm750fb/sm750.c:893:17: error: cannot assign to variable 'g_fbmode' with const-qualified type 'const char *const[2]'
893 | g_fbmode[0] = opt;
| ~~~~~~~~~~~ ^
drivers/staging/sm750fb/sm750.c:36:27: note: variable 'g_fbmode' declared const here
36 | static const char * const g_fbmode[] = {NULL, NULL};
| ~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
drivers/staging/sm750fb/sm750.c:897:17: error: cannot assign to variable 'g_fbmode' with const-qualified type 'const char *const[2]'
897 | g_fbmode[1] = opt;
| ~~~~~~~~~~~ ^
drivers/staging/sm750fb/sm750.c:36:27: note: variable 'g_fbmode' declared const here
36 | static const char * const g_fbmode[] = {NULL, NULL};
| ~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
4 errors generated.
vim +782 drivers/staging/sm750fb/sm750.c
81dee67e215b23f Sudip Mukherjee 2015-03-03 716
81dee67e215b23f Sudip Mukherjee 2015-03-03 717 static int lynxfb_set_fbinfo(struct fb_info *info, int index)
81dee67e215b23f Sudip Mukherjee 2015-03-03 718 {
81dee67e215b23f Sudip Mukherjee 2015-03-03 719 int i;
81dee67e215b23f Sudip Mukherjee 2015-03-03 720 struct lynxfb_par *par;
e359b6a863e19f2 Mike Rapoport 2015-10-26 721 struct sm750_dev *sm750_dev;
81dee67e215b23f Sudip Mukherjee 2015-03-03 722 struct lynxfb_crtc *crtc;
81dee67e215b23f Sudip Mukherjee 2015-03-03 723 struct lynxfb_output *output;
81dee67e215b23f Sudip Mukherjee 2015-03-03 724 struct fb_var_screeninfo *var;
81dee67e215b23f Sudip Mukherjee 2015-03-03 725 struct fb_fix_screeninfo *fix;
81dee67e215b23f Sudip Mukherjee 2015-03-03 726
81dee67e215b23f Sudip Mukherjee 2015-03-03 727 const struct fb_videomode *pdb[] = {
81dee67e215b23f Sudip Mukherjee 2015-03-03 728 lynx750_ext, NULL, vesa_modes,
81dee67e215b23f Sudip Mukherjee 2015-03-03 729 };
81dee67e215b23f Sudip Mukherjee 2015-03-03 730 int cdb[] = {ARRAY_SIZE(lynx750_ext), 0, VESA_MODEDB_SIZE};
8c475735085a7db Tim Wassink 2025-12-21 731 static const char *fix_id[2] = {
81dee67e215b23f Sudip Mukherjee 2015-03-03 732 "sm750_fb1", "sm750_fb2",
81dee67e215b23f Sudip Mukherjee 2015-03-03 733 };
81dee67e215b23f Sudip Mukherjee 2015-03-03 734
81dee67e215b23f Sudip Mukherjee 2015-03-03 735 int ret, line_length;
81dee67e215b23f Sudip Mukherjee 2015-03-03 736
81dee67e215b23f Sudip Mukherjee 2015-03-03 737 ret = 0;
81dee67e215b23f Sudip Mukherjee 2015-03-03 738 par = (struct lynxfb_par *)info->par;
e359b6a863e19f2 Mike Rapoport 2015-10-26 739 sm750_dev = par->dev;
81dee67e215b23f Sudip Mukherjee 2015-03-03 740 crtc = &par->crtc;
81dee67e215b23f Sudip Mukherjee 2015-03-03 741 output = &par->output;
81dee67e215b23f Sudip Mukherjee 2015-03-03 742 var = &info->var;
81dee67e215b23f Sudip Mukherjee 2015-03-03 743 fix = &info->fix;
81dee67e215b23f Sudip Mukherjee 2015-03-03 744
81dee67e215b23f Sudip Mukherjee 2015-03-03 745 /* set index */
81dee67e215b23f Sudip Mukherjee 2015-03-03 746 par->index = index;
81dee67e215b23f Sudip Mukherjee 2015-03-03 747 output->channel = &crtc->channel;
81dee67e215b23f Sudip Mukherjee 2015-03-03 748 sm750fb_set_drv(par);
81dee67e215b23f Sudip Mukherjee 2015-03-03 749
d11ac7cbcc266c6 Sudip Mukherjee 2015-08-07 750 /*
d11ac7cbcc266c6 Sudip Mukherjee 2015-08-07 751 * set current cursor variable and proc pointer,
d11ac7cbcc266c6 Sudip Mukherjee 2015-08-07 752 * must be set after crtc member initialized
d11ac7cbcc266c6 Sudip Mukherjee 2015-08-07 753 */
fdc234d85210d91 Benjamin Philip 2021-07-28 754 crtc->cursor.offset = crtc->o_screen + crtc->vidmem_size - 1024;
e359b6a863e19f2 Mike Rapoport 2015-10-26 755 crtc->cursor.mmio = sm750_dev->pvReg +
e359b6a863e19f2 Mike Rapoport 2015-10-26 756 0x800f0 + (int)crtc->channel * 0x140;
81dee67e215b23f Sudip Mukherjee 2015-03-03 757
cd33da26036ea54 Christopher Carbone 2022-08-23 758 crtc->cursor.max_h = 64;
cd33da26036ea54 Christopher Carbone 2022-08-23 759 crtc->cursor.max_w = 64;
39f9137268ee3df Benjamin Philip 2021-07-26 760 crtc->cursor.size = crtc->cursor.max_h * crtc->cursor.max_w * 2 / 8;
e359b6a863e19f2 Mike Rapoport 2015-10-26 761 crtc->cursor.vstart = sm750_dev->pvMem + crtc->cursor.offset;
81dee67e215b23f Sudip Mukherjee 2015-03-03 762
3de08a2d14ff8c7 Lorenzo Stoakes 2015-03-20 763 memset_io(crtc->cursor.vstart, 0, crtc->cursor.size);
f7c8a046577e09d Thomas Zimmermann 2023-11-27 764 if (!g_hwcursor)
52d0744d751d8f1 Arnd Bergmann 2016-11-09 765 sm750_hw_cursor_disable(&crtc->cursor);
81dee67e215b23f Sudip Mukherjee 2015-03-03 766
81dee67e215b23f Sudip Mukherjee 2015-03-03 767 /* set info->fbops, must be set before fb_find_mode */
e359b6a863e19f2 Mike Rapoport 2015-10-26 768 if (!sm750_dev->accel_off) {
81dee67e215b23f Sudip Mukherjee 2015-03-03 769 /* use 2d acceleration */
f7c8a046577e09d Thomas Zimmermann 2023-11-27 770 if (!g_hwcursor)
f7c8a046577e09d Thomas Zimmermann 2023-11-27 771 info->fbops = &lynxfb_ops_accel;
f7c8a046577e09d Thomas Zimmermann 2023-11-27 772 else
f7c8a046577e09d Thomas Zimmermann 2023-11-27 773 info->fbops = &lynxfb_ops_accel_with_cursor;
f7c8a046577e09d Thomas Zimmermann 2023-11-27 774 } else {
f7c8a046577e09d Thomas Zimmermann 2023-11-27 775 if (!g_hwcursor)
81dee67e215b23f Sudip Mukherjee 2015-03-03 776 info->fbops = &lynxfb_ops;
f7c8a046577e09d Thomas Zimmermann 2023-11-27 777 else
f7c8a046577e09d Thomas Zimmermann 2023-11-27 778 info->fbops = &lynxfb_ops_with_cursor;
f7c8a046577e09d Thomas Zimmermann 2023-11-27 779 }
81dee67e215b23f Sudip Mukherjee 2015-03-03 780
81dee67e215b23f Sudip Mukherjee 2015-03-03 781 if (!g_fbmode[index]) {
81dee67e215b23f Sudip Mukherjee 2015-03-03 @782 g_fbmode[index] = g_def_fbmode;
81dee67e215b23f Sudip Mukherjee 2015-03-03 783 if (index)
81dee67e215b23f Sudip Mukherjee 2015-03-03 784 g_fbmode[index] = g_fbmode[0];
81dee67e215b23f Sudip Mukherjee 2015-03-03 785 }
81dee67e215b23f Sudip Mukherjee 2015-03-03 786
81dee67e215b23f Sudip Mukherjee 2015-03-03 787 for (i = 0; i < 3; i++) {
81dee67e215b23f Sudip Mukherjee 2015-03-03 788 ret = fb_find_mode(var, info, g_fbmode[index],
81dee67e215b23f Sudip Mukherjee 2015-03-03 789 pdb[i], cdb[i], NULL, 8);
81dee67e215b23f Sudip Mukherjee 2015-03-03 790
db7fb3588ab4920 Artem Lytkin 2026-02-23 791 if (ret == 1 || ret == 2)
81dee67e215b23f Sudip Mukherjee 2015-03-03 792 break;
81dee67e215b23f Sudip Mukherjee 2015-03-03 793 }
81dee67e215b23f Sudip Mukherjee 2015-03-03 794
81dee67e215b23f Sudip Mukherjee 2015-03-03 795 /* set par */
81dee67e215b23f Sudip Mukherjee 2015-03-03 796 par->info = info;
81dee67e215b23f Sudip Mukherjee 2015-03-03 797
81dee67e215b23f Sudip Mukherjee 2015-03-03 798 /* set info */
e3a3f9f5123683b Mike Rapoport 2015-10-26 799 line_length = ALIGN((var->xres_virtual * var->bits_per_pixel / 8),
e3a3f9f5123683b Mike Rapoport 2015-10-26 800 crtc->line_pad);
81dee67e215b23f Sudip Mukherjee 2015-03-03 801
81dee67e215b23f Sudip Mukherjee 2015-03-03 802 info->pseudo_palette = &par->pseudo_palette[0];
cc59bde1c920ab6 Benjamin Philip 2021-07-28 803 info->screen_base = crtc->v_screen;
81dee67e215b23f Sudip Mukherjee 2015-03-03 804 info->screen_size = line_length * var->yres_virtual;
81dee67e215b23f Sudip Mukherjee 2015-03-03 805
81dee67e215b23f Sudip Mukherjee 2015-03-03 806 /* set info->fix */
81dee67e215b23f Sudip Mukherjee 2015-03-03 807 fix->type = FB_TYPE_PACKED_PIXELS;
81dee67e215b23f Sudip Mukherjee 2015-03-03 808 fix->type_aux = 0;
81dee67e215b23f Sudip Mukherjee 2015-03-03 809 fix->xpanstep = crtc->xpanstep;
81dee67e215b23f Sudip Mukherjee 2015-03-03 810 fix->ypanstep = crtc->ypanstep;
81dee67e215b23f Sudip Mukherjee 2015-03-03 811 fix->ywrapstep = crtc->ywrapstep;
81dee67e215b23f Sudip Mukherjee 2015-03-03 812 fix->accel = FB_ACCEL_SMI;
81dee67e215b23f Sudip Mukherjee 2015-03-03 813
8c475735085a7db Tim Wassink 2025-12-21 814 strscpy(fix->id, fix_id[index], sizeof(fix->id));
81dee67e215b23f Sudip Mukherjee 2015-03-03 815
fdc234d85210d91 Benjamin Philip 2021-07-28 816 fix->smem_start = crtc->o_screen + sm750_dev->vidmem_start;
d11ac7cbcc266c6 Sudip Mukherjee 2015-08-07 817 /*
d11ac7cbcc266c6 Sudip Mukherjee 2015-08-07 818 * according to mmap experiment from user space application,
81dee67e215b23f Sudip Mukherjee 2015-03-03 819 * fix->mmio_len should not larger than virtual size
81dee67e215b23f Sudip Mukherjee 2015-03-03 820 * (xres_virtual x yres_virtual x ByPP)
81dee67e215b23f Sudip Mukherjee 2015-03-03 821 * Below line maybe buggy when user mmap fb dev node and write
81dee67e215b23f Sudip Mukherjee 2015-03-03 822 * data into the bound over virtual size
d11ac7cbcc266c6 Sudip Mukherjee 2015-08-07 823 */
81dee67e215b23f Sudip Mukherjee 2015-03-03 824 fix->smem_len = crtc->vidmem_size;
81dee67e215b23f Sudip Mukherjee 2015-03-03 825 info->screen_size = fix->smem_len;
81dee67e215b23f Sudip Mukherjee 2015-03-03 826 fix->line_length = line_length;
e359b6a863e19f2 Mike Rapoport 2015-10-26 827 fix->mmio_start = sm750_dev->vidreg_start;
e359b6a863e19f2 Mike Rapoport 2015-10-26 828 fix->mmio_len = sm750_dev->vidreg_size;
b610e1193a917f4 Matej Dujava 2020-04-30 829
b610e1193a917f4 Matej Dujava 2020-04-30 830 lynxfb_set_visual_mode(info);
81dee67e215b23f Sudip Mukherjee 2015-03-03 831
81dee67e215b23f Sudip Mukherjee 2015-03-03 832 /* set var */
81dee67e215b23f Sudip Mukherjee 2015-03-03 833 var->activate = FB_ACTIVATE_NOW;
81dee67e215b23f Sudip Mukherjee 2015-03-03 834 var->accel_flags = 0;
81dee67e215b23f Sudip Mukherjee 2015-03-03 835 var->vmode = FB_VMODE_NONINTERLACED;
81dee67e215b23f Sudip Mukherjee 2015-03-03 836
61c507cf652da1b Michel von Czettritz 2015-03-26 837 ret = fb_alloc_cmap(&info->cmap, 256, 0);
61c507cf652da1b Michel von Czettritz 2015-03-26 838 if (ret < 0) {
fbab250eb51d6d6 Artem Lytkin 2026-02-07 839 dev_err(info->device, "Could not allocate memory for cmap.\n");
81dee67e215b23f Sudip Mukherjee 2015-03-03 840 goto exit;
81dee67e215b23f Sudip Mukherjee 2015-03-03 841 }
81dee67e215b23f Sudip Mukherjee 2015-03-03 842
81dee67e215b23f Sudip Mukherjee 2015-03-03 843 exit:
81dee67e215b23f Sudip Mukherjee 2015-03-03 844 lynxfb_ops_check_var(var, info);
81dee67e215b23f Sudip Mukherjee 2015-03-03 845 return ret;
81dee67e215b23f Sudip Mukherjee 2015-03-03 846 }
81dee67e215b23f Sudip Mukherjee 2015-03-03 847
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