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charset=us-ascii Content-Disposition: inline In-Reply-To: On Fri, Oct 11, 2024 at 06:25:45PM +0200, Christophe Leroy wrote: > > diff --git a/arch/powerpc/platforms/powermac/backlight.c b/arch/powerpc/platforms/powermac/backlight.c > > index 12bc01353bd3..79741370c40c 100644 > > --- a/arch/powerpc/platforms/powermac/backlight.c > > +++ b/arch/powerpc/platforms/powermac/backlight.c > > @@ -57,18 +57,10 @@ struct backlight_device *pmac_backlight; > > int pmac_has_backlight_type(const char *type) > > { > > struct device_node* bk_node = of_find_node_by_name(NULL, "backlight"); > > + int i = of_property_match_string(bk_node, "backlight-control", type); > > > > - if (bk_node) { > > - const char *prop = of_get_property(bk_node, > > - "backlight-control", NULL); > > - if (prop && strncmp(prop, type, strlen(type)) == 0) { > > - of_node_put(bk_node); > > - return 1; > > - } > > - of_node_put(bk_node); > > - } > > - > > - return 0; > > + of_node_put(bk_node); > > + return i >= 0; > > Could have been: > > return !IS_ERR_VALUE(i); > IS_ERR_VALUE() macro should only be used when you're dealing with memory addresses. What I mean is there places in mm/ where we pass addresses as unsigned long values instead of pointers. For example, get_unmapped_area() returns unsigned long. The IS_ERR_VALUE() macro is necessary for that. For regular error codes, we can just check for negatives. we don't have do anything fancy. Of course, you can find counter examples, like msm_iommu_attach_dev() or st_fdma_of_xlate(). But in those cases, it's done to deliberately to ensure that the code will never accidentally get built on 64bit systems. regards, dan carpenter