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 5DB241DE881; Mon, 2 Jun 2025 13:59:31 +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=1748872771; cv=none; b=L/JegbJ1fiIHF37ke/MA4ia0Ku2/Ild85XBoEOP0ZdR40ifzosoznK1u5z/evgvf7ffWWSortaca69BgWooIhWTZLDPnysMetXR4d4+M18+vUufmZezHwn5VYdevt28Z15fTMjQ9SUK7ZPBrP1/MVcrQ49wE0tTcc5Z8o6IQesI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1748872771; c=relaxed/simple; bh=gbZtnsvllV5Ceqy+uuGWvs6jMm4MghHqX3mxiLgN9JI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=bXJdyIZlWBz1+EOakprHgErYKFVeCHmCz3opK+gnv6LBtmtdFsXfcZSacLrSQBte17hjHDETHNZ3DMB1CSRK3Nh2v1+e3YA2SV90aEZqu7vRgxEgWAC6Dpl1BfWaxF0laSbT00X1WdFC7rjKKvtOKu3Q1UiFtyFKXtg8VEPVFmo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=nC6KeYa2; 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="nC6KeYa2" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C59E5C4CEEB; Mon, 2 Jun 2025 13:59:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1748872771; bh=gbZtnsvllV5Ceqy+uuGWvs6jMm4MghHqX3mxiLgN9JI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=nC6KeYa2bC4Zi5AFdXlEhf63iMP6BEkDtMG7L38TG8/OZOphI9UbFxBjuYYldT3Ye HqvFq2sTao5q5tdnTEqtY1hVZVVgnpvnhcCN37jSyszyMezPnuIBbqohTJvS9vI6qY sWLxT5XO2rx2s2mJJ1z6yvwU8OQEburW3Ax8Nu/E= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Alessandro Grassi , Mark Brown , Sasha Levin Subject: [PATCH 6.14 62/73] spi: spi-sun4i: fix early activation Date: Mon, 2 Jun 2025 15:47:48 +0200 Message-ID: <20250602134244.133334460@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250602134241.673490006@linuxfoundation.org> References: <20250602134241.673490006@linuxfoundation.org> User-Agent: quilt/0.68 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 6.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Alessandro Grassi [ Upstream commit fb98bd0a13de2c9d96cb5c00c81b5ca118ac9d71 ] The SPI interface is activated before the CPOL setting is applied. In that moment, the clock idles high and CS goes low. After a short delay, CPOL and other settings are applied, which may cause the clock to change state and idle low. This transition is not part of a clock cycle, and it can confuse the receiving device. To prevent this unexpected transition, activate the interface while CPOL and the other settings are being applied. Signed-off-by: Alessandro Grassi Link: https://patch.msgid.link/20250502095520.13825-1-alessandro.grassi@mailbox.org Signed-off-by: Mark Brown Signed-off-by: Sasha Levin --- drivers/spi/spi-sun4i.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/spi/spi-sun4i.c b/drivers/spi/spi-sun4i.c index fcbe864c9b7d6..4b070377e3d1d 100644 --- a/drivers/spi/spi-sun4i.c +++ b/drivers/spi/spi-sun4i.c @@ -264,6 +264,9 @@ static int sun4i_spi_transfer_one(struct spi_controller *host, else reg |= SUN4I_CTL_DHB; + /* Now that the settings are correct, enable the interface */ + reg |= SUN4I_CTL_ENABLE; + sun4i_spi_write(sspi, SUN4I_CTL_REG, reg); /* Ensure that we have a parent clock fast enough */ @@ -404,7 +407,7 @@ static int sun4i_spi_runtime_resume(struct device *dev) } sun4i_spi_write(sspi, SUN4I_CTL_REG, - SUN4I_CTL_ENABLE | SUN4I_CTL_MASTER | SUN4I_CTL_TP); + SUN4I_CTL_MASTER | SUN4I_CTL_TP); return 0; -- 2.39.5