ASoC: Taint the kernel if debugfs is used to write directly to CODECs

Since direct register writes may confuse the drivers and are supposed
to be used only in diagnostic situations discourage their use in
production by tainting the kernel when we do a write.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>

diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c
index bac7291b6ff625a131d461bd8e5123814bfb961d..96bf381683f7e68566ff60578ddb97600f6778b5 100644 (file)
--- a/sound/soc/soc-core.c
+++ b/sound/soc/soc-core.c
@@ -209,6 +209,10 @@ static ssize_t codec_reg_write_file(struct file *file,
                start++;
        if (strict_strtoul(start, 16, &value))
                return -EINVAL;
+
+       /* Userspace has been fiddling around behind the kernel's back */
+       add_taint(TAINT_USER);
+
        snd_soc_write(codec, reg, value);
        return buf_size;
 }