linux-kernel - [PATCH v4 09/16] drm/msm/hdmi: add runtime PM calls to DDC transfer function

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20250209-fd-hdmi-hpd-v4-9-6224568ed87f@linaro.org>
Date: Sun, 09 Feb 2025 07:04:53 +0200
From: Dmitry Baryshkov <dmitry.baryshkov@...aro.org>
To: Rob Clark <robdclark@...il.com>, 
 Abhinav Kumar <quic_abhinavk@...cinc.com>, Sean Paul <sean@...rly.run>, 
 Marijn Suijten <marijn.suijten@...ainline.org>, 
 David Airlie <airlied@...il.com>, Simona Vetter <simona@...ll.ch>, 
 Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>, 
 Maxime Ripard <mripard@...nel.org>, Thomas Zimmermann <tzimmermann@...e.de>, 
 Rob Herring <robh@...nel.org>, Krzysztof Kozlowski <krzk+dt@...nel.org>, 
 Conor Dooley <conor+dt@...nel.org>, Bjorn Andersson <andersson@...nel.org>, 
 Konrad Dybcio <konradybcio@...nel.org>, 
 Simona Vetter <simona.vetter@...ll.ch>
Cc: linux-arm-msm@...r.kernel.org, dri-devel@...ts.freedesktop.org, 
 freedreno@...ts.freedesktop.org, linux-kernel@...r.kernel.org, 
 devicetree@...r.kernel.org, Jessica Zhang <quic_jesszhan@...cinc.com>
Subject: [PATCH v4 09/16] drm/msm/hdmi: add runtime PM calls to DDC
 transfer function

We must be sure that the HDMI controller is powered on, while performing
the DDC transfer. Add corresponding runtime PM calls to
msm_hdmi_i2c_xfer().

Reviewed-by: Jessica Zhang <quic_jesszhan@...cinc.com>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@...aro.org>
---
 drivers/gpu/drm/msm/hdmi/hdmi_i2c.c | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/msm/hdmi/hdmi_i2c.c b/drivers/gpu/drm/msm/hdmi/hdmi_i2c.c
index 7aa500d24240ff3ed6694c469eafc4388c982346..ebefea4fb40855745001ed97367d571bde28f413 100644
--- a/drivers/gpu/drm/msm/hdmi/hdmi_i2c.c
+++ b/drivers/gpu/drm/msm/hdmi/hdmi_i2c.c
@@ -107,11 +107,15 @@ static int msm_hdmi_i2c_xfer(struct i2c_adapter *i2c,
 	if (num == 0)
 		return num;
 
+	ret = pm_runtime_resume_and_get(&hdmi->pdev->dev);
+	if (ret)
+		return ret;
+
 	init_ddc(hdmi_i2c);
 
 	ret = ddc_clear_irq(hdmi_i2c);
 	if (ret)
-		return ret;
+		goto fail;
 
 	for (i = 0; i < num; i++) {
 		struct i2c_msg *p = &msgs[i];
@@ -169,7 +173,7 @@ static int msm_hdmi_i2c_xfer(struct i2c_adapter *i2c,
 				hdmi_read(hdmi, REG_HDMI_DDC_SW_STATUS),
 				hdmi_read(hdmi, REG_HDMI_DDC_HW_STATUS),
 				hdmi_read(hdmi, REG_HDMI_DDC_INT_CTRL));
-		return ret;
+		goto fail;
 	}
 
 	ddc_status = hdmi_read(hdmi, REG_HDMI_DDC_SW_STATUS);
@@ -202,7 +206,13 @@ static int msm_hdmi_i2c_xfer(struct i2c_adapter *i2c,
 		}
 	}
 
+	pm_runtime_put(&hdmi->pdev->dev);
+
 	return i;
+
+fail:
+	pm_runtime_put(&hdmi->pdev->dev);
+	return ret;
 }
 
 static u32 msm_hdmi_i2c_func(struct i2c_adapter *adapter)

-- 
2.39.5