ALSA: hda: Use regcache_reg_cached() rather than open coding

The HDA driver intentionally drops repeated writes to registers in some circumstances, beyond the suppression of noop writes that regmap does in regmap_update_bits(). It does this by checking if the register is cached before doing a regmap_update_bits(), now we have an API for querying this directly use it directly rather than trying a read in cache only mode making the code a little clearer. Reviewed-by: Takashi Iwai <[email protected]> Signed-off-by: Mark Brown <[email protected]> Link: https://lore.kernel.org/r/[email protected] Signed-off-by: Mark Brown <[email protected]>
niw · Jul 18, 2023 · 99aae70 · 99aae70
1 parent d881ee5
commit 99aae70
Showing 1 changed file with 3 additions and 6 deletions.
diff --git a/sound/hda/hdac_regmap.c b/sound/hda/hdac_regmap.c
@@ -556,17 +556,14 @@ EXPORT_SYMBOL_GPL(snd_hdac_regmap_update_raw);
 static int reg_raw_update_once(struct hdac_device *codec, unsigned int reg,
 			       unsigned int mask, unsigned int val)
 {
-	unsigned int orig;
-	int err;
+	int err = 0;
 
 	if (!codec->regmap)
 		return reg_raw_update(codec, reg, mask, val);
 
 	mutex_lock(&codec->regmap_lock);
-	regcache_cache_only(codec->regmap, true);
-	err = regmap_read(codec->regmap, reg, &orig);
-	regcache_cache_only(codec->regmap, false);
-	if (err < 0)
+	/* Discard any updates to already initialised registers. */
+	if (!regcache_reg_cached(codec->regmap, reg))
 		err = regmap_update_bits(codec->regmap, reg, mask, val);
 	mutex_unlock(&codec->regmap_lock);
 	return err;