Messages in this thread | | | Subject | Re: [PATCH v2 1/1] lib/vsprintf: Add support for printing V4L2 and DRM fourccs | From | Joe Perches <> | Date | Mon, 06 Apr 2020 06:01:17 -0700 |
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On Mon, 2020-04-06 at 13:44 +0300, Andy Shevchenko wrote: > On Mon, Apr 6, 2020 at 10:46 AM Mauro Carvalho Chehab > <mchehab+huawei@kernel.org> wrote: > > Em Fri, 3 Apr 2020 21:32:42 +0300 > > Andy Shevchenko <andy.shevchenko@gmail.com> escreveu: > > > On Fri, Apr 3, 2020 at 8:54 PM Joe Perches <joe@perches.com> wrote: > > > > On Fri, 2020-04-03 at 19:32 +0200, Mauro Carvalho Chehab wrote: > > > > > Em Fri, 03 Apr 2020 09:56:42 -0700 > > > > > Joe Perches <joe@perches.com> escreveu: > > > > It _might_ be useful to use a CONFIG_MEDIA_SUPPORT guard > > > > in lib/vsprintf for this. > > > > > > No need. FourCC, if Sakari makes it more generic, can be used for > > > other purposes, e.g. printing component names from the chips (not > > > related to media at all). > > > > > > > Hmm... not 100% sure about what you're meaning with "component names". > > 4cc is pretty much wide standard, media is just one of (famous) users of it. > > As I emphasized the example I referring to has nothing to do with media. > > Now, I have already two examples: > - component name inside hardware register (used by Synopsys DesignWare) > - CSRT table in ACPI uses this code for vendor ID.
So if this is really u32_to_ascii, perhaps the "-BE" bit should be separated and "%4pEp" could be used with some renamed inline used like ERR_PTR so maybe something like this might work?
static inline void * __must_check FOURCC(u32 val) { return (void *)(unsigned long)cpu_to_be32(val); }
void test_4cc(void) { u32 val = 0x41424344;
printk("4cc like: %4pE\n", FOURCC(val)); }
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