ASoC: cs42l42: Regmap must use_single_read/write

[ Upstream commit 0fad605 ]

cs42l42 does not support standard burst transfers so the use_single_read
and use_single_write flags must be set in the regmap config.

Because of this bug, the patch:

commit 0a0eb56 ("ASoC: cs42l42: Minor error paths fixups")

broke cs42l42 probe() because without the use_single_* flags it causes
regmap to issue a burst read.

However, the missing use_single_* could cause problems anyway because the
regmap cache can attempt burst transfers if these flags are not set.

Fixes: 2c394ca ("ASoC: Add support for CS42L42 codec")
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Acked-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Link: https://lore.kernel.org/r/20210511132855.27159-1-rf@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

sound/soc/codecs/cs42l42.c

@@ -398,6 +398,9 @@ static const struct regmap_config cs42l42_regmap = {
 	.reg_defaults = cs42l42_reg_defaults,
 	.num_reg_defaults = ARRAY_SIZE(cs42l42_reg_defaults),
 	.cache_type = REGCACHE_RBTREE,
+
+	.use_single_read = true,
+	.use_single_write = true,
 };
 
 static DECLARE_TLV_DB_SCALE(adc_tlv, -9600, 100, false);