From faac764ea1ea6898d93e46c403271fb105c0906e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20Povi=C5=A1er?= <povik+lin@cutebit.org>
Date: Thu, 27 Oct 2022 11:57:59 +0200
Subject: [PATCH] ASoC: tas2764: Fix set_tdm_slot in case of single slot
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Git-commit: faac764ea1ea6898d93e46c403271fb105c0906e
Patch-mainline: v6.1-rc6
References: git-fixes

There's a special branch in the set_tdm_slot op for the case of nslots
being 1, but:

 (1) That branch can never work (there's a check for tx_mask being
     non-zero, later there's another check for it *being* zero; one or
     the other always throws -EINVAL).

 (2) The intention of the branch seems to be what the general other
     branch reduces to in case of nslots being 1.

For those reasons remove the 'nslots being 1' special case.

Fixes: 827ed8a0fa50 ("ASoC: tas2764: Add the driver for the TAS2764")
Suggested-by: Jos Dehaes <jos.dehaes@gmail.com>
Signed-off-by: Martin Povišer <povik+lin@cutebit.org>
Link: https://lore.kernel.org/r/20221027095800.16094-2-povik+lin@cutebit.org
Signed-off-by: Mark Brown <broonie@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 sound/soc/codecs/tas2764.c | 19 ++++++-------------
 1 file changed, 6 insertions(+), 13 deletions(-)

diff --git a/sound/soc/codecs/tas2764.c b/sound/soc/codecs/tas2764.c
index 51b87a936179..2e0ed3e68fa5 100644
--- a/sound/soc/codecs/tas2764.c
+++ b/sound/soc/codecs/tas2764.c
@@ -438,20 +438,13 @@ static int tas2764_set_dai_tdm_slot(struct snd_soc_dai *dai,
 	if (tx_mask == 0 || rx_mask != 0)
 		return -EINVAL;
 
-	if (slots == 1) {
-		if (tx_mask != 1)
-			return -EINVAL;
-		left_slot = 0;
-		right_slot = 0;
+	left_slot = __ffs(tx_mask);
+	tx_mask &= ~(1 << left_slot);
+	if (tx_mask == 0) {
+		right_slot = left_slot;
 	} else {
-		left_slot = __ffs(tx_mask);
-		tx_mask &= ~(1 << left_slot);
-		if (tx_mask == 0) {
-			right_slot = left_slot;
-		} else {
-			right_slot = __ffs(tx_mask);
-			tx_mask &= ~(1 << right_slot);
-		}
+		right_slot = __ffs(tx_mask);
+		tx_mask &= ~(1 << right_slot);
 	}
 
 	if (tx_mask != 0 || left_slot >= slots || right_slot >= slots)
-- 
2.35.3