On Fri, 2020-04-03 at 14:10 +0200, Rasmus Villemoes wrote: > On 03/04/2020 11.11, Sakari Ailus wrote: > > Add a printk modifier %ppf (for pixel format) for printing V4L2 and DRM > > pixel formats denoted by 4ccs. The 4cc encoding is the same for both so > > the same implementation can be used. > > This seems quite niche to me, I'm not sure that belongs in vsprintf.c. > What's wrong with having a > > char *fourcc_string(char *buf, u32 x) > > that formats x into buf and returns buf, so it can be used in a > > char buf[8]; > pr_debug("bla: %s\n", fourcc_string(buf, x)) Nothing really, it's a number of uses question. For networking code, print_mac was used before %pM. After Linus floated the idea of %p<foo>, %pM was introduced and all the DECLARE_MAC_BUF/print_mac calls were converted. %pM did reduce overall object size a fair amount. How many instances of %p4cc could there be?