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=1794062794; b=n/f55imOWvjNmVBlt80QW1+nhbA++W3CZz6hJf9x+fu7k2eERzlxB8Di3vuQGSPxl4fH N7joWP8SGaEAhpm+uANSjrEnsDTitymrGU4Hx211ZYr3wHesSk41475Gk8Frn6pqmjjvv 8RngSedrQBd6bOb1qKgOD93KehAN3k2PhlWMey+s0WbVWD6toQb8mnYDN0J0sTljy+RJ2 1l072TgNfj+536bewa9TjAPeCG8Kp9lLtHpjYf/tr+96Lf/xx5IcxURi+nuOjUO70TagA jqNOOfC89R0PJm6NG5Y3EeRncqvmeNHcuCpoJocSOzDj7mIWbDE0I4TPLI3nyKP6z7g== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794062794; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=Sae2eOkkoCBxbkcO7hENwj2Clvo+lYWPJcQkvDkQH3g=; b=bfs/m4IzTvkaPRpzlV5Q016HFjk+4A6rP5kdjoDwrp7X1h1ZLU/S95wnmoQYJ8W2S+Ab ksh+bue1PYRsVB+uNE3tLjyDIrPcpXR6Xz4ZQzs2r3VkK4ugk5lmRgX/CLuO9jXOxsQ5m ESMVmoeIQUL4YQxJTvdpDaSW0uBEzKI5MhYfucTcX79GOibOtIUR9Du/tTl3+/QISlmip FMY3JhpX4937FxLxmQQKjbCwqL2UbiAFvyQlZqjgM6N7nlCTEx7G+Y+xm9Y3xgL0244ah w9QnUuictmh2A2KWIDBRQktvBeX32HIaSutaPUWU/zJezd80imlL8GPaFTH4asxqXKA== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=xEgVr3cJ; 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 124EE606A32F; Sat, 7 Nov 2026 14:46:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=xEgVr3cJ Received: by smtp.kernel.org (Postfix) with ESMTPSA id 768D91F008A2; Sat, 7 Nov 2026 14:46:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794062793; bh=Sae2eOkkoCBxbkcO7hENwj2Clvo+lYWPJcQkvDkQH3g=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=xEgVr3cJ9OE8V9UtGztTC1zxlwHza1vfV6SLcu23AbOeDNEYAYZf6e7kROuS3tZwz sqt59ub64hjjWXdd2+3+JgSHB9oaXnnvl9kPA6KhOn9I3hsZtFoqLD0E3C8MkAYSOf SV0KEG6CXM4VO60EUdfJ512l1GF0vXaiQ7WJmxLk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Eugen Hristev , Balakrishnan Sambath , Hans Verkuil , Sasha Levin Subject: [PATCH 6.18 098/869] media: microchip-isc: do not touch WB registers when not streaming Date: Sat, 7 Nov 2026 08:46:20 -0500 Message-ID: <20261107134855.987125905@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261107134852.069646174@linuxfoundation.org> References: <20261107134852.069646174@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore 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 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ 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 --- .../platform/microchip/microchip-isc-base.c | 20 +++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) diff --git a/drivers/media/platform/microchip/microchip-isc-base.c b/drivers/media/platform/microchip/microchip-isc-base.c index 0f486dd5bd82c..cf4611443fd13 100644 --- a/drivers/media/platform/microchip/microchip-isc-base.c +++ b/drivers/media/platform/microchip/microchip-isc-base.c @@ -1511,20 +1511,24 @@ 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