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From: Arnd Bergmann <arnd@kernel.org>
To: Liam Girdwood <lgirdwood@gmail.com>,
	Mark Brown <broonie@kernel.org>, Jaroslav Kysela <perex@perex.cz>,
	Takashi Iwai <tiwai@suse.com>,
	Chen Wang <unicorn_wang@outlook.com>,
	Inochi Amaoto <inochiama@gmail.com>,
	"Anton D. Stavinskii" <stavinsky@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>,
	linux-sound@vger.kernel.org, sophgo@lists.linux.dev,
	linux-kernel@vger.kernel.org
Subject: [PATCH] ASoC: sophgo: fix 64-bit division build failure
Date: Mon,  2 Feb 2026 10:53:14 +0100	[thread overview]
Message-ID: <20260202095323.1233553-1-arnd@kernel.org> (raw)

From: Arnd Bergmann <arnd@arndb.de>

cv1800b_adc_setbclk_div() does four 64-bit divisions in a row, which
is rather inefficient on 32-bit systems, and using the plain division
causes a build failure as a result:

ERROR: modpost: "__aeabi_uldivmod" [sound/soc/sophgo/cv1800b-sound-adc.ko] undefined!

Consolidate those into a single division using the div_u64() macro.

Fixes: 4cf8752a03e6 ("ASoC: sophgo: add CV1800B internal ADC codec driver")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 sound/soc/sophgo/cv1800b-sound-adc.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/sound/soc/sophgo/cv1800b-sound-adc.c b/sound/soc/sophgo/cv1800b-sound-adc.c
index 794030b713e9..b66761156b99 100644
--- a/sound/soc/sophgo/cv1800b-sound-adc.c
+++ b/sound/soc/sophgo/cv1800b-sound-adc.c
@@ -105,11 +105,8 @@ static int cv1800b_adc_setbclk_div(struct cv1800b_priv *priv, unsigned int rate)
 	if (!priv->mclk_rate || !rate)
 		return -EINVAL;
 
-	tmp = priv->mclk_rate;
-	tmp /= CV1800B_RXADC_WORD_LEN;
-	tmp /= CV1800B_RXADC_CHANNELS;
-	tmp /= rate;
-	tmp /= 2;
+	tmp = div_u64(priv->mclk_rate, CV1800B_RXADC_WORD_LEN *
+		      CV1800B_RXADC_CHANNELS * rate * 2);
 
 	if (!tmp) {
 		dev_err(priv->dev, "computed BCLK divider is zero\n");
-- 
2.39.5


             reply	other threads:[~2026-02-02  9:53 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-02-02  9:53 Arnd Bergmann [this message]
2026-02-02 21:31 ` [PATCH] ASoC: sophgo: fix 64-bit division build failure Alexander Sverdlin
2026-02-02 22:00   ` Arnd Bergmann
2026-02-02 22:48 ` Mark Brown
2026-02-03  0:11   ` Chen Wang

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