ALSA: hda - Implement unbind more safely

Now we have all pieces ready, and put them into places:
- add the hda_pcm refcount to azx_pcm_open() and azx_pcm_close(),
- call the most of cleanup code in hda_codec_reset() from the codec
  driver remove,
- call the same code also from the hda_codec object free.

Then the codec driver can be unbound more safely now.

Signed-off-by: Takashi Iwai <tiwai@suse.de>

5 files changed, 43 insertions, 35 deletions

diff --git a/sound/pci/hda/hda_bind.c b/sound/pci/hda/hda_bind.c
index 2d00417494e2..311896a23cd1 100644
--- a/sound/pci/hda/hda_bind.c
+++ b/sound/pci/hda/hda_bind.c
@@ -125,8 +125,7 @@ static int hda_codec_driver_remove(struct device *dev)
 
         if (codec->patch_ops.free)
                 codec->patch_ops.free(codec);
-        codec->preset = NULL;
-        memset(&codec->patch_ops, 0, sizeof(codec->patch_ops));
+        snd_hda_codec_cleanup_for_unbind(codec);
         module_put(dev->driver->owner);
         return 0;
 }
diff --git a/sound/pci/hda/hda_codec.c b/sound/pci/hda/hda_codec.c
index 3bd9158addc2..2c7e481a9171 100644
--- a/sound/pci/hda/hda_codec.c
+++ b/sound/pci/hda/hda_codec.c
@@ -1160,36 +1160,62 @@ struct hda_pcm *snd_hda_codec_pcm_new(struct hda_codec *codec,
 }
 EXPORT_SYMBOL_GPL(snd_hda_codec_pcm_new);
 
+/*
+ * codec destructor
+ */
 static void codec_release_pcms(struct hda_codec *codec)
 {
         struct hda_pcm *pcm, *n;
 
         list_for_each_entry_safe(pcm, n, &codec->pcm_list_head, list) {
                 list_del_init(&pcm->list);
+                if (pcm->pcm)
+                        snd_device_disconnect(codec->card, pcm->pcm);
                 snd_hda_codec_pcm_put(pcm);
         }
 }
 
-/*
- * codec destructor
- */
+void snd_hda_codec_cleanup_for_unbind(struct hda_codec *codec)
+{
+        cancel_delayed_work_sync(&codec->jackpoll_work);
+        flush_workqueue(codec->bus->workq);
+        if (!codec->in_freeing)
+                snd_hda_ctls_clear(codec);
+        codec_release_pcms(codec);
+        snd_hda_detach_beep_device(codec);
+        memset(&codec->patch_ops, 0, sizeof(codec->patch_ops));
+        snd_hda_jack_tbl_clear(codec);
+        codec->proc_widget_hook = NULL;
+        codec->spec = NULL;
+
+        free_hda_cache(&codec->amp_cache);
+        free_hda_cache(&codec->cmd_cache);
+        init_hda_cache(&codec->amp_cache, sizeof(struct hda_amp_info));
+        init_hda_cache(&codec->cmd_cache, sizeof(struct hda_cache_head));
+
+        /* free only driver_pins so that init_pins + user_pins are restored */
+        snd_array_free(&codec->driver_pins);
+        snd_array_free(&codec->cvt_setups);
+        snd_array_free(&codec->spdif_out);
+        snd_array_free(&codec->verbs);
+        codec->preset = NULL;
+        codec->slave_dig_outs = NULL;
+        codec->spdif_status_reset = 0;
+        snd_array_free(&codec->mixers);
+        snd_array_free(&codec->nids);
+        remove_conn_list(codec);
+}
+
 static void snd_hda_codec_free(struct hda_codec *codec)
 {
         if (!codec)
                 return;
-        cancel_delayed_work_sync(&codec->jackpoll_work);
-        codec_release_pcms(codec);
+        codec->in_freeing = 1;
         if (device_is_registered(hda_codec_dev(codec)))
                 device_del(hda_codec_dev(codec));
-        snd_hda_jack_tbl_clear(codec);
         free_init_pincfgs(codec);
         flush_workqueue(codec->bus->workq);
         list_del(&codec->list);
-        snd_array_free(&codec->mixers);
-        snd_array_free(&codec->nids);
-        snd_array_free(&codec->cvt_setups);
-        snd_array_free(&codec->spdif_out);
-        remove_conn_list(codec);
         codec->bus->caddr_tbl[codec->addr] = NULL;
         clear_bit(codec->addr, &codec->bus->codec_powered);
         snd_hda_sysfs_clear(codec);
@@ -2479,31 +2505,9 @@ int snd_hda_codec_reset(struct hda_codec *codec)
                 return -EBUSY;
 
         /* OK, let it free */
-        cancel_delayed_work_sync(&codec->jackpoll_work);
-        flush_workqueue(bus->workq);
-        snd_hda_ctls_clear(codec);
-        codec_release_pcms(codec);
-        snd_hda_detach_beep_device(codec);
         if (device_is_registered(hda_codec_dev(codec)))
                 device_del(hda_codec_dev(codec));
 
-        memset(&codec->patch_ops, 0, sizeof(codec->patch_ops));
-        snd_hda_jack_tbl_clear(codec);
-        codec->proc_widget_hook = NULL;
-        codec->spec = NULL;
-        free_hda_cache(&codec->amp_cache);
-        free_hda_cache(&codec->cmd_cache);
-        init_hda_cache(&codec->amp_cache, sizeof(struct hda_amp_info));
-        init_hda_cache(&codec->cmd_cache, sizeof(struct hda_cache_head));
-        /* free only driver_pins so that init_pins + user_pins are restored */
-        snd_array_free(&codec->driver_pins);
-        snd_array_free(&codec->cvt_setups);
-        snd_array_free(&codec->spdif_out);
-        snd_array_free(&codec->verbs);
-        codec->preset = NULL;
-        codec->slave_dig_outs = NULL;
-        codec->spdif_status_reset = 0;
-
         /* allow device access again */
         snd_hda_unlock_devices(bus);
         return 0;
diff --git a/sound/pci/hda/hda_codec.h b/sound/pci/hda/hda_codec.h
index 2ccd6f9a91fe..fc62ca51fd35 100644
--- a/sound/pci/hda/hda_codec.h
+++ b/sound/pci/hda/hda_codec.h
@@ -350,6 +350,7 @@ struct hda_codec {
 #endif
 
         /* misc flags */
+        unsigned int in_freeing:1; /* being released */
         unsigned int spdif_status_reset :1; /* needs to toggle SPDIF for each
                                              * status change
                                              * (e.g. Realtek codecs)
diff --git a/sound/pci/hda/hda_controller.c b/sound/pci/hda/hda_controller.c
index ad85f9bfaf57..cae50d5ffb81 100644
--- a/sound/pci/hda/hda_controller.c
+++ b/sound/pci/hda/hda_controller.c
@@ -420,6 +420,7 @@ static int azx_pcm_close(struct snd_pcm_substream *substream)
                 hinfo->ops.close(hinfo, apcm->codec, substream);
         snd_hda_power_down(apcm->codec);
         mutex_unlock(&chip->open_mutex);
+        snd_hda_codec_pcm_put(apcm->info);
         return 0;
 }
 
@@ -806,6 +807,7 @@ static int azx_pcm_open(struct snd_pcm_substream *substream)
         int err;
         int buff_step;
 
+        snd_hda_codec_pcm_get(apcm->info);
         mutex_lock(&chip->open_mutex);
         azx_dev = azx_assign_device(chip, substream);
         if (azx_dev == NULL) {
@@ -887,6 +889,7 @@ static int azx_pcm_open(struct snd_pcm_substream *substream)
         snd_hda_power_down(apcm->codec);
  unlock:
         mutex_unlock(&chip->open_mutex);
+        snd_hda_codec_pcm_put(apcm->info);
         return err;
 }
 
diff --git a/sound/pci/hda/hda_local.h b/sound/pci/hda/hda_local.h
index 8588813163e3..1d001647fc47 100644
--- a/sound/pci/hda/hda_local.h
+++ b/sound/pci/hda/hda_local.h
@@ -150,6 +150,7 @@ int __snd_hda_add_vmaster(struct hda_codec *codec, char *name,
 #define snd_hda_add_vmaster(codec, name, tlv, slaves, suffix) \
         __snd_hda_add_vmaster(codec, name, tlv, slaves, suffix, true, NULL)
 int snd_hda_codec_reset(struct hda_codec *codec);
+void snd_hda_codec_cleanup_for_unbind(struct hda_codec *codec);
 
 enum {
         HDA_VMUTE_OFF,