drm/mgag200: Return errno codes from PLL compute functions

Return -EINVAL if there's no PLL configuration for the given pixel
clock. The returned errors are currently ignored by the caller, but
the errno codes will become useful when the compute functions run
during atomic checks.

v2:
	* give a rational for this change (Sam)

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210714142240.21979-3-tzimmermann@suse.de

diff --git a/drivers/gpu/drm/mgag200/mgag200_mode.c b/drivers/gpu/drm/mgag200/mgag200_mode.c
index 1bdf21474bcb29012dc458fe61df6486b5fa71d6..69daa0fd73c902fd720e299d75864e8afbcc8174 100644 (file)
--- a/drivers/gpu/drm/mgag200/mgag200_mode.c
+++ b/drivers/gpu/drm/mgag200/mgag200_mode.c
@@ -133,7 +133,7 @@ static int mgag200_g200_set_plls(struct mga_device *mdev, long clock)
 
        if (clock > p_clk_max) {
                drm_err(dev, "Pixel Clock %ld too high\n", clock);
-               return 1;
+               return -EINVAL;
        }
 
        if (clock < p_clk_min >> 3)
@@ -288,7 +288,7 @@ static int mga_g200se_set_plls(struct mga_device *mdev, long clock)
 
        if (delta > permitteddelta) {
                pr_warn("PLL delta too large\n");
-               return 1;
+               return -EINVAL;
        }
 
        WREG_MISC_MASKED(MGAREG_MISC_CLKSEL_MGA, MGAREG_MISC_CLKSEL_MASK);