ASoC: tas2781: add module parameter to tascodec_init()

The tascodec_init() of the snd-soc-tas2781-comlib module is called from
snd-soc-tas2781-i2c and snd-hda-scodec-tas2781-i2c modules. It calls
request_firmware_nowait() with parameter THIS_MODULE and a cont/callback
from the latter modules.

The latter modules can be removed while their callbacks are running,
resulting in a general protection failure.

Add module parameter to tascodec_init() so request_firmware_nowait() can
be called with the module of the callback.

Fixes: ef3bcde ("ASoC: tas2781: Add tas2781 driver")
CC: stable@vger.kernel.org
Signed-off-by: Gergo Koteles <soyer@irl.hu>
Link: https://lore.kernel.org/r/118dad922cef50525e5aab09badef2fa0eb796e5.1707076603.git.soyer@irl.hu
Signed-off-by: Mark Brown <broonie@kernel.org>

include/sound/tas2781.h

@@ -142,6 +142,7 @@ struct tasdevice_priv {
 
 void tas2781_reset(struct tasdevice_priv *tas_dev);
 int tascodec_init(struct tasdevice_priv *tas_priv, void *codec,
+	struct module *module,
 	void (*cont)(const struct firmware *fw, void *context));
 struct tasdevice_priv *tasdevice_kzalloc(struct i2c_client *i2c);
 int tasdevice_init(struct tasdevice_priv *tas_priv);

sound/pci/hda/tas2781_hda_i2c.c

@@ -710,7 +710,7 @@ static int tas2781_hda_bind(struct device *dev, struct device *master,
 
 	strscpy(comps->name, dev_name(dev), sizeof(comps->name));
 
-	ret = tascodec_init(tas_hda->priv, codec, tasdev_fw_ready);
+	ret = tascodec_init(tas_hda->priv, codec, THIS_MODULE, tasdev_fw_ready);
 	if (!ret)
 		comps->playback_hook = tas2781_hda_playback_hook;
 

sound/soc/codecs/tas2781-comlib.c

@@ -267,6 +267,7 @@ void tas2781_reset(struct tasdevice_priv *tas_dev)
 EXPORT_SYMBOL_GPL(tas2781_reset);
 
 int tascodec_init(struct tasdevice_priv *tas_priv, void *codec,
+	struct module *module,
 	void (*cont)(const struct firmware *fw, void *context))
 {
 	int ret = 0;
@@ -280,7 +281,7 @@ int tascodec_init(struct tasdevice_priv *tas_priv, void *codec,
 		tas_priv->dev_name, tas_priv->ndev);
 	crc8_populate_msb(tas_priv->crc8_lkp_tbl, TASDEVICE_CRC8_POLYNOMIAL);
 	tas_priv->codec = codec;
-	ret = request_firmware_nowait(THIS_MODULE, FW_ACTION_UEVENT,
+	ret = request_firmware_nowait(module, FW_ACTION_UEVENT,
 		tas_priv->rca_binaryname, tas_priv->dev, GFP_KERNEL, tas_priv,
 		cont);
 	if (ret)

sound/soc/codecs/tas2781-i2c.c

@@ -566,7 +566,7 @@ static int tasdevice_codec_probe(struct snd_soc_component *codec)
 {
 	struct tasdevice_priv *tas_priv = snd_soc_component_get_drvdata(codec);
 
-	return tascodec_init(tas_priv, codec, tasdevice_fw_ready);
+	return tascodec_init(tas_priv, codec, THIS_MODULE, tasdevice_fw_ready);
 }
 
 static void tasdevice_deinit(void *context)