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=1794063914; b=njrGWj2qPehPnszXjbeM9f1Ez4pjysPpWbeoTQerqLGyhxNqU+LFzXqgwVN5ZvmwvmYf YoW4pVSN3hLcEBCR15KkkKZfCyiHLoW9zqjdHN6Ar6H/Aa8fiBzQM48nOY7KWvT+BstdG rYeqsTWsJX7iNRpsZspM0T/OwY9El+fbsbdOU0tQY/HO3+h+OAGmmVPlTzsYiGKq2Pu8P 1npFkIoLQlfgDlTo/FpfS6YpzUYiALNhgoRvsnJIEOxxxUm8z/rsAcP7u52sUUoNOfUcN xFbOTkAMvdTniAmKQSvw/5OMMy/VfBey+ye6bB0NzWvtSxepMIDLo+hY8kDRs/aV1pw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794063914; 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=628kTryIbQ4XKWYaRll+HsSXNABEYgH12Tx3gSfBxSs=; b=MElD3mWrui6ZdlVbiOpHDpUXAGEu9zj/di7dVoHUCgU7PVow1MxRGmv/078eSy/ih1yy x5DIIrODUROBrkQI4Pd+cC/P/fFZMixZ7Hm1HV4SP2Psnm4Lje94MrMIdpxeuvMlbHaH0 SiPwQbJ800nVyVuiST2UWRhfYt26zSQNreFKipDbSEOAAujNizG9M3RDrZ7WuzWcWivS4 QCDmyJ6Fb58LNtD6ET8mijjJ2JjYOAfBEUF6+Hde+WFyEYOuSIh4udrClbVwypCq/TrKT CYf3zQIvDKBlrpIWTr0zq2BZzC94ytqZrR5v9/sl0/9kU8xr+Jwi8t9sCYNLxkORj8Q== 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=cVPZzOfu; 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 A2958606E8E9; Sat, 7 Nov 2026 15:05:13 +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=cVPZzOfu Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5142B1F0089F; Sat, 7 Nov 2026 15:05:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1794063913; bh=628kTryIbQ4XKWYaRll+HsSXNABEYgH12Tx3gSfBxSs=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=cVPZzOfu2ZOwcFtFZ+dZt5nPz/sLizpJX/ZeSgwAovay2A3nx7ljCcd1wpNQ3IuQz d94OCVW5zEU7o3q7i9kDrbZaF++6CVda6iPLmMo446+AH1n1Eayhz1MDbCoEvFEEOy pGpnky21E7oLQRQkflN90ifc0S870e1y8Q4zJflY= 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 7.3 0111/1257] media: microchip-isc: do not touch WB registers when not streaming Date: Sat, 7 Nov 2026 08:40:07 -0500 Message-ID: <20261107134942.417003734@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261107134939.434104957@linuxfoundation.org> References: <20261107134939.434104957@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 7.3-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