From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A2F69322749; Mon, 20 Apr 2026 15:57:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776700677; cv=none; b=BFeECe6qQb80vSNj9AJfSDwaN6kJERMcmudGdjzflLJhH8hoC4WIiJDIRnxRgakRJbML2z0jmD8i/D9WwtCoaOX1+DhrOCqbEJ7RUMESzyD7+JB2M2YFB24bXrEN3fedofaG9ZJ2XlIFIqwex33Oave0rIyCfz19ZpfXVUA22hw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776700677; c=relaxed/simple; bh=TPi22R44xO568q+Uygf+kYA5OOEL8WcbWzmA810CJ7w=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Fgw9CyuFmQPGH+hA+2kJjMpReuarIiJ6vc7n8XZeaKMPSXUwUE7rKwgVSM2Ah7CLTEqVQ1xU1sW3JItGrWolI4avPydukMnMZHDWzfeyZDdd6uULFSuyrcuKmvPMwfWY2pcOSr3GZhacPVR2tbViEJhaYGz0cfbwOpsb+2RGa3c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Lt4/H3cC; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="Lt4/H3cC" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 38F46C19425; Mon, 20 Apr 2026 15:57:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1776700677; bh=TPi22R44xO568q+Uygf+kYA5OOEL8WcbWzmA810CJ7w=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Lt4/H3cCCtq0qpJLV0m9gGueKKCF1dTsOwLBnGbtmdqV+0D4q3A5j3BsRL7tPYgJG 5PTZ8iT7iltB2bJtKBvvPlCVrLRGTRmkKTvf58ce6fsi8FHRWJeDjJwPcqN8IvmIfG uuF5HNQYPAI7tQdppzMAQT/yh9zReb+hak1zNB94= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Tomasz Merta , Mark Brown , Sasha Levin Subject: [PATCH 6.18 045/198] ASoC: stm32_sai: fix incorrect BCLK polarity for DSP_A/B, LEFT_J Date: Mon, 20 Apr 2026 17:40:24 +0200 Message-ID: <20260420153937.239661336@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260420153935.605963767@linuxfoundation.org> References: <20260420153935.605963767@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Tomasz Merta [ Upstream commit 0669631dbccd41cf3ca7aa70213fcd8bb41c4b38 ] The STM32 SAI driver do not set the clock strobing bit (CKSTR) for DSP_A, DSP_B and LEFT_J formats, causing data to be sampled on the wrong BCLK edge when SND_SOC_DAIFMT_NB_NF is used. Per ALSA convention, NB_NF requires sampling on the rising BCLK edge. The STM32MP25 SAI reference manual states that CKSTR=1 is required for signals received by the SAI to be sampled on the SCK rising edge. Without setting CKSTR=1, the SAI samples on the falling edge, violating the NB_NF convention. For comparison, the NXP FSL SAI driver correctly sets FSL_SAI_CR2_BCP for DSP_A, DSP_B and LEFT_J, consistent with its I2S handling. This patch adds SAI_XCR1_CKSTR for DSP_A, DSP_B and LEFT_J in stm32_sai_set_dai_fmt which was verified empirically with a cs47l35 codec. RIGHT_J (LSB) is not investigated and addressed by this patch. Note: the STM32 I2S driver (stm32_i2s_set_dai_fmt) may have the same issue for DSP_A mode, as I2S_CGFR_CKPOL is not set. This has not been verified and is left for a separate investigation. Signed-off-by: Tomasz Merta Link: https://patch.msgid.link/20260408084056.20588-1-tommerta@gmail.com Signed-off-by: Mark Brown Signed-off-by: Sasha Levin --- sound/soc/stm/stm32_sai_sub.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/sound/soc/stm/stm32_sai_sub.c b/sound/soc/stm/stm32_sai_sub.c index 5ae4d2577f28b..c2540383ab86f 100644 --- a/sound/soc/stm/stm32_sai_sub.c +++ b/sound/soc/stm/stm32_sai_sub.c @@ -802,6 +802,7 @@ static int stm32_sai_set_dai_fmt(struct snd_soc_dai *cpu_dai, unsigned int fmt) break; /* Left justified */ case SND_SOC_DAIFMT_MSB: + cr1 |= SAI_XCR1_CKSTR; frcr |= SAI_XFRCR_FSPOL | SAI_XFRCR_FSDEF; break; /* Right justified */ @@ -809,9 +810,11 @@ static int stm32_sai_set_dai_fmt(struct snd_soc_dai *cpu_dai, unsigned int fmt) frcr |= SAI_XFRCR_FSPOL | SAI_XFRCR_FSDEF; break; case SND_SOC_DAIFMT_DSP_A: + cr1 |= SAI_XCR1_CKSTR; frcr |= SAI_XFRCR_FSPOL | SAI_XFRCR_FSOFF; break; case SND_SOC_DAIFMT_DSP_B: + cr1 |= SAI_XCR1_CKSTR; frcr |= SAI_XFRCR_FSPOL; break; default: -- 2.53.0