The jack detection bit on 
AD1986A Lenovo N100 seems inverse from
the standard definition.  Now fixed the detection properly.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
        unsigned int present;
 
        present = snd_hda_codec_read(codec, 0x1a, 0, AC_VERB_GET_PIN_SENSE, 0);
-       spec->jack_present = (present & 0x80000000) != 0;
+       /* Lenovo N100 seems to report the reversed bit for HP jack-sensing */
+       spec->jack_present = !(present & 0x80000000);
        ad1986a_update_hp(codec);
 }