From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794362875; b=OaMrcRwwwBYhtr3ZXw77l+I/N9epwvIPIV5cf+YirnZATbBPOFY7Rlg9coudbQ2JdJT7 ffxRsULo2ZF32SFIymDyfH4UuMIFQveAaCn6eY9IncuVzAwcHDGmRRQxEB4oUnREzPGu8 ElDw2CaSLLXVoItNgVR3Xuvfx/a+kdYsaARbhebWuiY5yXXb6S4rzNVdo7wHxWBr5IK8l sCjXnQqI7yKCml0mDVAFQRpZeD426hvTn3ECpyqpbKMlxNYpJh6FPBUC7Lzq65mrAEZdn 1YJp3h58pZiEiXH9oK8PMI50evuky0RQAijbApwNI1lS610+i2Pi6tG5ydWo8iJYJQg== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794362875; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:Content-Transfer-Encoding; bh=EQnxXiLJSaGBuehV5g3jLOh0vg7FsSp7kbqitemc1ww=; b=XzdKGsF1Am38uunHDJP3l1JOgdqJQeCicb2LPLKqW15BLZ8oOPKUll+unjR/ohDzv/r/ 1NA6USGzcSrEb9N59E1vSCgrx97CjI3GsWkZPcI9wH3PgajTXtKnLisfW8Vr5ZvXMM6GL WK0d4K0U24dGzFDgExttUTWys5PxR9lNdci8qq7+s2KgizeZSm81P5Cp8rvWjy2U4p9If IL6CEcojWYOwBYCC136Dx0CoChO4FypExYjk9/O/fOamqzPDAXn8CBiZmG4hKk8PWTiy9 aw9MUBf26r4cWWjM4t3wKNqEyYjEeOXH8NzoaK5fz0iAwJiCCwKTx3HfFI/YdQuSTWQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=cV4rIIKE; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id EF345606A31C for ; Wed, 11 Nov 2026 02:07:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=cV4rIIKE Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3E31D1F0089F; Wed, 11 Nov 2026 02:07:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794362874; bh=EQnxXiLJSaGBuehV5g3jLOh0vg7FsSp7kbqitemc1ww=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=cV4rIIKEYTd66FXAzTeEeOB9xFtONJiKFLsQOO2t8Rujt5FRy+CPHgaFgzIkvZxMP ba4QSpLavJ2z0vneZXXS7JkYgJiZZAytvWjOX9byVghPfuw+/OBcddlYmWJ8EEXex4 aSDVj2tFVw81I/dmxPPj2gxQ7E5Yi/y+yn4whpmqls86zwOHMV4qD5jVqiEISyKrqb aDlVaJl1ueGb8v28krrS9v5HKndDSvxLEkY3N/rakBjGI5LViIGoq0ZQk9JepBGwq6 lluA0LoRexLyFHGXXbuLSLe3Jz3ChG+lWp1XvRsiWenXGaQufE/T5ihu3yrx3b6fVG qyG3pm1MbKoTg== From: Sasha Levin To: stable@vger.kernel.org Cc: Balakrishnan Sambath , Eugen Hristev , Hans Verkuil , Sasha Levin Subject: [PATCH 5.15.y 3/3] media: microchip-isc: do not touch WB registers when not streaming Date: Tue, 10 Nov 2026 21:07:51 -0500 Message-ID: <20261111020626.487609-3-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20261111020626.487609-1-sashal@kernel.org> References: <20261107055759-failed-5.15-d8983c47d4d9@kernel.org> <20261111020626.487609-1-sashal@kernel.org> X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Balakrishnan Sambath [ Upstream commit d8983c47d4d95eb1ed889dbb7516d3738fa854d8 ] isc_s_awb_ctrl() called isc_update_awb_ctrls() unconditionally, writing the white balance registers even when the device is runtime suspended; on many ARM platforms accessing the unclocked registers is an external abort. The write was also done without awb_lock, racing isc_awb_work(), which holds it so the DMA done IRQ cannot latch a half-updated pipeline. Write the registers only while streaming and not stopping, under awb_lock, and update the profile there. The isc->stop check covers the window where isc_stop_streaming() has gated the clocks but vb2 still reports streaming. Otherwise the new values stay cached and isc_configure() programs them at the next stream start. Fixes: 4e52889f48fe ("media: atmel: atmel-isc-base: expose white balance as v4l2 controls") Cc: stable@vger.kernel.org Reviewed-by: Eugen Hristev Signed-off-by: Balakrishnan Sambath Signed-off-by: Hans Verkuil Signed-off-by: Sasha Levin --- drivers/media/platform/atmel/atmel-isc-base.c | 20 +++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) diff --git a/drivers/media/platform/atmel/atmel-isc-base.c b/drivers/media/platform/atmel/atmel-isc-base.c index 565719fda13c3..dc12424965f3e 100644 --- a/drivers/media/platform/atmel/atmel-isc-base.c +++ b/drivers/media/platform/atmel/atmel-isc-base.c @@ -1843,20 +1843,24 @@ static int isc_s_awb_ctrl(struct v4l2_ctrl *ctrl) if (ctrl->cluster[ISC_CTRL_GB_OFF]->is_new) ctrls->offset[ISC_HIS_CFG_MODE_GB] = isc->gb_off_ctrl->val; - isc_update_awb_ctrls(isc); - mutex_lock(&isc->awb_mutex); - if (vb2_is_streaming(&isc->vb2_vidq)) { + if (vb2_is_streaming(&isc->vb2_vidq) && !isc->stop) { + unsigned long flags; + /* - * If we are streaming, we can update profile to - * have the new settings in place. + * awb_lock keeps the DMA done IRQ from latching a + * partially written WB pipeline. */ + spin_lock_irqsave(&isc->awb_lock, flags); + isc_update_awb_ctrls(isc); + spin_unlock_irqrestore(&isc->awb_lock, flags); + isc_update_profile(isc); } else { /* - * The auto cluster will activate automatically this - * control. This has to be deactivated when not - * streaming. + * Not streaming: keep the cached values for the next + * stream start and deactivate the cluster-activated + * do_white_balance button. */ v4l2_ctrl_activate(isc->do_wb_ctrl, false); } -- 2.53.0