From:   Trevor Wu <trevor.wu@mediatek.com>
To:     <broonie@kernel.org>, <lgirdwood@gmail.com>, <tiwai@suse.com>,
        <perex@perex.cz>, <matthias.bgg@gmail.com>
CC:     <trevor.wu@mediatek.com>, <alsa-devel@alsa-project.org>,
        <linux-mediatek@lists.infradead.org>,
        <linux-arm-kernel@lists.infradead.org>,
        <linux-kernel@vger.kernel.org>, <error27@gmail.com>
Subject: [PATCH] ASoC: mediatek: mt8188: remove etdm dead code
Date:   Thu, 2 Feb 2023 18:37:04 +0800
Message-ID: <20230202103704.15626-1-trevor.wu@mediatek.com>
MIME-Version: 1.0
Content-Type: text/plain
Precedence: bulk

Some Smatch static checker warning like below was found.

sound/soc/mediatek/mt8188/mt8188-dai-etdm.c:2487
mt8188_dai_etdm_parse_of()
warn: 'ret' returned from snprintf() might be larger than 48

    2479         for (i = 0; i < MT8188_AFE_IO_ETDM_NUM; i++) {
    2480                 dai_id = ETDM_TO_DAI_ID(i);
    2481                 etdm_data = afe_priv->dai_priv[dai_id];
    2482
    2483                 ret = snprintf(prop, sizeof(prop),
    2484                                "mediatek,%s-multi-pin-mode",
    2485                                of_afe_etdms[i].name);
    2486                 if (ret < 0) {
--> 2487                         dev_err(afe->dev, "%s snprintf
err=%d\n",
    2488

In linux kernel, snprintf() never returns negatives. On the other hand,
the format string like "mediatek,%s-multi-pin-mode" must be smaller
than sizeof(prop)=48.

After discussing in the mail thread[1], I remove the dead code to fix
the Smatch warnings.

[1]: https://lore.kernel.org/all/Y9EdBg641tJDDrt%2F@kili/

Signed-off-by: Trevor Wu <trevor.wu@mediatek.com>
---
 sound/soc/mediatek/mt8188/mt8188-dai-etdm.c | 33 ++++++---------------
 1 file changed, 9 insertions(+), 24 deletions(-)

diff --git a/sound/soc/mediatek/mt8188/mt8188-dai-etdm.c b/sound/soc/mediatek/mt8188/mt8188-dai-etdm.c
index 0b79c1cc293b..071841903c62 100644
--- a/sound/soc/mediatek/mt8188/mt8188-dai-etdm.c
+++ b/sound/soc/mediatek/mt8188/mt8188-dai-etdm.c
@@ -2480,24 +2480,14 @@ static void mt8188_dai_etdm_parse_of(struct mtk_base_afe *afe)
 		dai_id = ETDM_TO_DAI_ID(i);
 		etdm_data = afe_priv->dai_priv[dai_id];
 
-		ret = snprintf(prop, sizeof(prop),
-			       "mediatek,%s-multi-pin-mode",
-			       of_afe_etdms[i].name);
-		if (ret < 0) {
-			dev_err(afe->dev, "%s snprintf err=%d\n",
-				__func__, ret);
-			return;
-		}
+		snprintf(prop, sizeof(prop), "mediatek,%s-multi-pin-mode",
+			 of_afe_etdms[i].name);
+
 		etdm_data->data_mode = of_property_read_bool(of_node, prop);
 
-		ret = snprintf(prop, sizeof(prop),
-			       "mediatek,%s-cowork-source",
-			       of_afe_etdms[i].name);
-		if (ret < 0) {
-			dev_err(afe->dev, "%s snprintf err=%d\n",
-				__func__, ret);
-			return;
-		}
+		snprintf(prop, sizeof(prop), "mediatek,%s-cowork-source",
+			 of_afe_etdms[i].name);
+
 		ret = of_property_read_u32(of_node, prop, &sel);
 		if (ret == 0) {
 			if (sel >= MT8188_AFE_IO_ETDM_NUM) {
@@ -2516,14 +2506,9 @@ static void mt8188_dai_etdm_parse_of(struct mtk_base_afe *afe)
 
 	/* etdm in only */
 	for (i = 0; i < 2; i++) {
-		ret = snprintf(prop, sizeof(prop),
-			       "mediatek,%s-chn-disabled",
-			       of_afe_etdms[i].name);
-		if (ret < 0) {
-			dev_err(afe->dev, "%s snprintf err=%d\n",
-				__func__, ret);
-			return;
-		}
+		snprintf(prop, sizeof(prop), "mediatek,%s-chn-disabled",
+			 of_afe_etdms[i].name);
+
 		ret = of_property_read_variable_u8_array(of_node, prop,
 							 disable_chn,
 							 1, max_chn);
-- 
2.18.0