[PATCH v4 2/2] ALSA: hda/tas2781: Cancel async firmware request at unbind

[Cássio Gabriel]

TAS2781 HDA I2C and SPI queue RCA firmware loading from component
bind with request_firmware_nowait(). The firmware loader keeps the
callback module pinned and holds a device reference, but the callback
still uses driver-private HDA state.

Component unbind removes controls and DSP state immediately. Later
device removal tears down the TAS2781 private data, including
codec_lock. If the async firmware callback runs after unbind has
started, it can operate on state that is being torn down.

Cancel or synchronize the async firmware request before removing
controls and DSP state. A queued callback is cancelled, and an
already-running callback is allowed to finish before unbind continues.

Fixes: 5be27f1e3ec9 ("ALSA: hda/tas2781: Add tas2781 HDA driver")
Fixes: bb5f86ea50ff ("ALSA: hda/tas2781: Add tas2781 hda SPI driver")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Cássio Gabriel <cassiogabrielcontato@xxxxxxxxx>
---
 sound/hda/codecs/side-codecs/tas2781_hda_i2c.c | 3 +++
 sound/hda/codecs/side-codecs/tas2781_hda_spi.c | 3 +++
 2 files changed, 6 insertions(+)

diff --git a/sound/hda/codecs/side-codecs/tas2781_hda_i2c.c b/sound/hda/codecs/side-codecs/tas2781_hda_i2c.c
index 67240ce184e1..dd1b0cc63ad6 100644
--- a/sound/hda/codecs/side-codecs/tas2781_hda_i2c.c
+++ b/sound/hda/codecs/side-codecs/tas2781_hda_i2c.c
@@ -588,6 +588,9 @@ static void tas2781_hda_unbind(struct device *dev,
 		comp->playback_hook = NULL;
 	}
 
+	request_firmware_nowait_cancel(tas_hda->priv->dev, tas_hda->priv,
+				       tasdev_fw_ready);
+
 	tas2781_hda_remove_controls(tas_hda);
 
 	tasdevice_config_info_remove(tas_hda->priv);
diff --git a/sound/hda/codecs/side-codecs/tas2781_hda_spi.c b/sound/hda/codecs/side-codecs/tas2781_hda_spi.c
index 0e4f3553f273..d243baff95a7 100644
--- a/sound/hda/codecs/side-codecs/tas2781_hda_spi.c
+++ b/sound/hda/codecs/side-codecs/tas2781_hda_spi.c
@@ -750,6 +750,9 @@ static void tas2781_hda_unbind(struct device *dev, struct device *master,
 		comp->playback_hook = NULL;
 	}
 
+	request_firmware_nowait_cancel(tas_priv->dev, tas_priv,
+				       tasdev_fw_ready);
+
 	tas2781_hda_remove_controls(tas_hda);
 
 	tasdevice_config_info_remove(tas_priv);

-- 
2.54.0