[alsa-devel] [PATCH] soc-core: move setting ac97 platform data earlier than ac97 read/write

[Barry Song]

While probing, AC97 codec drivers generically execute the following sequence:
snd_soc_new_ac97_codec -> snd_soc_new_pcms -> reset ac-link/read AC97 ID to
detect ->...  -> snd_soc_init_card

commit 474828a40f6ddab6e2a3475a19c5c84aa3ec7d60 adds platform_data to
snd_ac97 instance. But ac97 platform data hasn't given to snd_ac97 until
snd_soc_init_card. Then while ac97_read access platform_data of snd_ac97
for detecting, NULL pointer oops will fire. That means old platform_data
patch doesn't work in real-life cases.

This patch moves the operation of setting ac97 platform_data earlier
than ac97 reading/writing operations. Then it makes platform_data of
AC97 become practically useful.

Signed-off-by: Barry Song <21cnbao at gmail.com>
cc: Marek Vasut <marek.vasut at gmail.com>
---
 sound/soc/soc-core.c |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c
index 2d190df..a900778 100644
--- a/sound/soc/soc-core.c
+++ b/sound/soc/soc-core.c
@@ -1427,6 +1427,9 @@ int snd_soc_new_pcms(struct snd_soc_device *socdev, int idx, const char *xid)
 			mutex_unlock(&codec->mutex);
 			return ret;
 		}
+		if (card->dai_link[i].codec_dai->ac97_control)
+			snd_ac97_dev_add_pdata(codec->ac97,
+					card->dai_link[i].cpu_dai->ac97_pdata);
 	}
 
 	mutex_unlock(&codec->mutex);
@@ -1458,11 +1461,8 @@ int snd_soc_init_card(struct snd_soc_device *socdev)
 				continue;
 			}
 		}
-		if (card->dai_link[i].codec_dai->ac97_control) {
+		if (card->dai_link[i].codec_dai->ac97_control)
 			ac97 = 1;
-			snd_ac97_dev_add_pdata(codec->ac97,
-				card->dai_link[i].cpu_dai->ac97_pdata);
-		}
 	}
 	snprintf(codec->card->shortname, sizeof(codec->card->shortname),
 		 "%s",  card->name);
-- 
1.5.6.3