On Tue, 16 Feb 2016 17:59:04 +0100, Arnd Bergmann wrote:
On Tuesday 16 February 2016 16:38:40 Mark Brown wrote:
On Tue, Feb 16, 2016 at 05:18:29PM +0100, Takashi Iwai wrote:
Arnd Bergmann wrote:
Another option might would be to change snd_jack_new() to return an error if that SND_JACK is disabled, and then require all users to handle the error gracefully, i.e. not fail the probe() function but just not use the jack.
Yes, I thought of that, too. If select is no good option, it's a good alternative, indeed.
It's going to be a bunch of work to implement though.
I've already sent a v2 to change the snd_jack_new() function, feel free to ignore that. I also saw now that the same bug is present in hda_jack.c, but I think the other drivers are fine.
How about this approach below? That should also make it possible to use the jack APIs without using a error return.
I prefer setting NULL explicitly in snd_jack_new(), and let callers checking NULL. Then we can avoid ugly IS_ENABLE() while the compiler should be still capable to optimize out.
OTOH, I think it'd be a waste of time to bikeshedding too much, so I don't care so much which to take :)
Takashi
--- diff --git a/include/sound/jack.h b/include/sound/jack.h index 23bede121c78..a27c253a3207 100644 --- a/include/sound/jack.h +++ b/include/sound/jack.h @@ -99,6 +99,7 @@ void snd_jack_report(struct snd_jack *jack, int status); static inline int snd_jack_new(struct snd_card *card, const char *id, int type, struct snd_jack **jack, bool initial_kctl, bool phantom_jack) { + *jack = NULL; return 0; }
diff --git a/sound/pci/hda/hda_jack.c b/sound/pci/hda/hda_jack.c index a33234e04d4f..babd3a8864a1 100644 --- a/sound/pci/hda/hda_jack.c +++ b/sound/pci/hda/hda_jack.c @@ -403,10 +403,12 @@ int snd_hda_jack_add_kctl(struct hda_codec *codec, hda_nid_t nid,
jack->phantom_jack = !!phantom_jack; jack->type = type; - jack->jack->private_data = jack; - jack->jack->private_free = hda_free_jack_priv; - state = snd_hda_jack_detect(codec, nid); - snd_jack_report(jack->jack, state ? jack->type : 0); + if (jack->jack) { + jack->jack->private_data = jack; + jack->jack->private_free = hda_free_jack_priv; + state = snd_hda_jack_detect(codec, nid); + snd_jack_report(jack->jack, state ? jack->type : 0); + }
return 0; } diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c index 8ee78dbd4c60..34a7b3aaba11 100644 --- a/sound/pci/hda/patch_hdmi.c +++ b/sound/pci/hda/patch_hdmi.c @@ -2158,8 +2158,10 @@ static int add_acomp_jack_kctl(struct hda_codec *codec, if (err < 0) return err; per_pin->acomp_jack = jack; - jack->private_data = per_pin; - jack->private_free = free_acomp_jack_priv; + if (jack) { + jack->private_data = per_pin; + jack->private_free = free_acomp_jack_priv; + } return 0; }