diff options
| author | Colin Ian King <colin.king@canonical.com> | 2020-07-23 20:02:27 +0300 |
|---|---|---|
| committer | Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> | 2020-09-08 14:33:03 +0300 |
| commit | c72fab81ceaa54408b827a2f0486d9a0f4be34cf (patch) | |
| tree | 933dfb217b7de3e3ca53feda947a6ec1ffc751d4 /drivers/video/fbdev/vga16fb.c | |
| parent | bcee1609ba9623f35597f06a2ad118ac4ade2974 (diff) | |
| download | linux-c72fab81ceaa54408b827a2f0486d9a0f4be34cf.tar.xz | |
video: fbdev: vga16fb: fix setting of pixclock because a pass-by-value error
The pixclock is being set locally because it is being passed as a
pass-by-value argument rather than pass-by-reference, so the computed
pixclock is never being set in var->pixclock. Fix this by passing
by reference.
[This dates back to 2002, I found the offending commit from the git
history git://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git ]
Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Jani Nikula <jani.nikula@intel.com>
[b.zolnierkie: minor patch summary fixup]
[b.zolnierkie: removed "Fixes:" tag (not in upstream tree)]
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200723170227.996229-1-colin.king@canonical.com
Diffstat (limited to 'drivers/video/fbdev/vga16fb.c')
| -rw-r--r-- | drivers/video/fbdev/vga16fb.c | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/drivers/video/fbdev/vga16fb.c b/drivers/video/fbdev/vga16fb.c index a20eeb8308ff..52f273af6cae 100644 --- a/drivers/video/fbdev/vga16fb.c +++ b/drivers/video/fbdev/vga16fb.c @@ -243,7 +243,7 @@ static void vga16fb_update_fix(struct fb_info *info) } static void vga16fb_clock_chip(struct vga16fb_par *par, - unsigned int pixclock, + unsigned int *pixclock, const struct fb_info *info, int mul, int div) { @@ -259,14 +259,14 @@ static void vga16fb_clock_chip(struct vga16fb_par *par, { 0 /* bad */, 0x00, 0x00}}; int err; - pixclock = (pixclock * mul) / div; + *pixclock = (*pixclock * mul) / div; best = vgaclocks; - err = pixclock - best->pixclock; + err = *pixclock - best->pixclock; if (err < 0) err = -err; for (ptr = vgaclocks + 1; ptr->pixclock; ptr++) { int tmp; - tmp = pixclock - ptr->pixclock; + tmp = *pixclock - ptr->pixclock; if (tmp < 0) tmp = -tmp; if (tmp < err) { err = tmp; @@ -275,7 +275,7 @@ static void vga16fb_clock_chip(struct vga16fb_par *par, } par->misc |= best->misc; par->clkdiv = best->seq_clock_mode; - pixclock = (best->pixclock * div) / mul; + *pixclock = (best->pixclock * div) / mul; } #define FAIL(X) return -EINVAL @@ -497,10 +497,10 @@ static int vga16fb_check_var(struct fb_var_screeninfo *var, if (mode & MODE_8BPP) /* pixel clock == vga clock / 2 */ - vga16fb_clock_chip(par, var->pixclock, info, 1, 2); + vga16fb_clock_chip(par, &var->pixclock, info, 1, 2); else /* pixel clock == vga clock */ - vga16fb_clock_chip(par, var->pixclock, info, 1, 1); + vga16fb_clock_chip(par, &var->pixclock, info, 1, 1); var->red.offset = var->green.offset = var->blue.offset = var->transp.offset = 0; |