From nobody Sun Feb 8 10:03:50 2026 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 D29941D435F; Thu, 8 Jan 2026 15:17:25 +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=1767885445; cv=none; b=Rtu09STYham1RHPoUa/AMzyLWy82pX+5rrwLIMTsaoPvNSAAPhhzFix7NdBjYn6qmnBWPrcr0iw0KsuHHNVsHctppbLvC+zIohzqhvsC3h7zcvtuI6204qpKgGKt48InX3pH+aAaq0ssGDSMvzAwQW4W+JNm2aOrjX7hkkUWK44= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767885445; c=relaxed/simple; bh=MVUd2mPnw+PufvW3fzHiPeR63pakRAw7EqgNUPsOg8c=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-Type; b=LlziPR7Axb3Ehmv2alDk0kdUWBFLPj7bAIK3Yto9wIPdgzqhoQ/q3UBXisUpVdvmjAyHpg9Es+ZglIv/whs56Asl5ApSnevk3Vf9fTuj3EWVtvLhwCFk9yS7IGLqNfYqAtVPZgxadOSOYMQL2DLmqpKZ6KaCcFtDG51eySMsJHE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=e6LkVeGw; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="e6LkVeGw" Received: by smtp.kernel.org (Postfix) with ESMTPSA id F2AD8C116C6; Thu, 8 Jan 2026 15:17:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1767885445; bh=MVUd2mPnw+PufvW3fzHiPeR63pakRAw7EqgNUPsOg8c=; h=From:To:Cc:Subject:Date:From; b=e6LkVeGwqmyg+tZH00Pbv0sUjzTkZ12hr4mI6KY0y5j/pn3xpEA6XlYZYLKfDz5BP 2+O12PQ5UQgnMp3F4lemyx63nnkyEhvmchahR9tizUdowPNeIwCDFYQ2HX6zTaRPZM 7fAe82FflAY0g8j2p8pOS17mtkiUXCA2IEphud0uVFqh3K1tZbYaB01w2eEIx7YEWj 9ASDWjyeIqg3zYQYE2+hp/tQfz46VeCKKJ8VTLKIleupiny7QrbM+0/fnftgyjU8Q3 /AR7D/CNyl/eo8U9LjAsy2VKyBN0w/KI55RKnL0tXA5DzwXVXx9this1SLqztjgHcd 7XpXhHOsXfYug== From: "Rafael J. Wysocki" To: Linux PM , imx@lists.linux.dev Cc: LKML , Ulf Hansson , Brian Norris , Liviu Dudau , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Shawn Guo , Sascha Hauer , Fabio Estevam , Dave Stevenson , Raspberry Pi Kernel Maintenance , dri-devel@lists.freedesktop.org, =?ISO-8859-1?Q?Ma=EDra?= Canal Subject: [RESEND][PATCH v1] drm: Discard pm_runtime_put() return value Date: Thu, 08 Jan 2026 16:17:17 +0100 Message-ID: <2256082.irdbgypaU6@rafael.j.wysocki> Organization: Linux Kernel Development Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: Rafael J. Wysocki Multiple DRM drivers use the pm_runtime_put() return value for printing debug or even error messages and all of those messages are at least somewhat misleading. Returning an error code from pm_runtime_put() merely means that it has not queued up a work item to check whether or not the device can be suspended and there are many perfectly valid situations in which that can happen, like after writing "on" to the devices' runtime PM "control" attribute in sysfs for one example. It also happens when the kernel has been configured with CONFIG_PM unset. For this reason, modify all of those drivers to simply discard the pm_runtime_put() return value which is what they should be doing. This will facilitate a planned change of the pm_runtime_put() return type to void in the future. Signed-off-by: Rafael J. Wysocki Acked-by: Dave Stevenson Acked-by: Liviu Dudau --- This patch is requisite for converting pm_runtime_put() into a void function. If you decide to pick it up, please let me know. Otherwise, an ACK or equivalent will be appreciated, but also the lack of specific criticism will be eventually regarded as consent. Originally posted here: https://lore.kernel.org/linux-pm/3045480.e9J7NaK4W3@rafael.j.wysocki/ --- drivers/gpu/drm/arm/malidp_crtc.c | 6 +----- drivers/gpu/drm/bridge/imx/imx8qm-ldb.c | 4 +--- drivers/gpu/drm/bridge/imx/imx8qxp-ldb.c | 4 +--- drivers/gpu/drm/bridge/imx/imx8qxp-pixel-combiner.c | 5 +---- drivers/gpu/drm/bridge/imx/imx8qxp-pxl2dpi.c | 5 +---- drivers/gpu/drm/imx/dc/dc-crtc.c | 12 +++--------- drivers/gpu/drm/vc4/vc4_hdmi.c | 5 +---- drivers/gpu/drm/vc4/vc4_vec.c | 12 ++---------- 8 files changed, 11 insertions(+), 42 deletions(-) --- a/drivers/gpu/drm/arm/malidp_crtc.c +++ b/drivers/gpu/drm/arm/malidp_crtc.c @@ -77,7 +77,6 @@ static void malidp_crtc_atomic_disable(s crtc); struct malidp_drm *malidp =3D crtc_to_malidp_device(crtc); struct malidp_hw_device *hwdev =3D malidp->dev; - int err; =20 /* always disable planes on the CRTC that is being turned off */ drm_atomic_helper_disable_planes_on_crtc(old_state, false); @@ -87,10 +86,7 @@ static void malidp_crtc_atomic_disable(s =20 clk_disable_unprepare(hwdev->pxlclk); =20 - err =3D pm_runtime_put(crtc->dev->dev); - if (err < 0) { - DRM_DEBUG_DRIVER("Failed to disable runtime power management: %d\n", err= ); - } + pm_runtime_put(crtc->dev->dev); } =20 static const struct gamma_curve_segment { --- a/drivers/gpu/drm/bridge/imx/imx8qm-ldb.c +++ b/drivers/gpu/drm/bridge/imx/imx8qm-ldb.c @@ -280,9 +280,7 @@ static void imx8qm_ldb_bridge_atomic_dis clk_disable_unprepare(imx8qm_ldb->clk_bypass); clk_disable_unprepare(imx8qm_ldb->clk_pixel); =20 - ret =3D pm_runtime_put(dev); - if (ret < 0) - DRM_DEV_ERROR(dev, "failed to put runtime PM: %d\n", ret); + pm_runtime_put(dev); } =20 static const u32 imx8qm_ldb_bus_output_fmts[] =3D { --- a/drivers/gpu/drm/bridge/imx/imx8qxp-ldb.c +++ b/drivers/gpu/drm/bridge/imx/imx8qxp-ldb.c @@ -282,9 +282,7 @@ static void imx8qxp_ldb_bridge_atomic_di if (is_split && companion) companion->funcs->atomic_disable(companion, state); =20 - ret =3D pm_runtime_put(dev); - if (ret < 0) - DRM_DEV_ERROR(dev, "failed to put runtime PM: %d\n", ret); + pm_runtime_put(dev); } =20 static const u32 imx8qxp_ldb_bus_output_fmts[] =3D { --- a/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-combiner.c +++ b/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-combiner.c @@ -181,11 +181,8 @@ static void imx8qxp_pc_bridge_atomic_dis { struct imx8qxp_pc_channel *ch =3D bridge->driver_private; struct imx8qxp_pc *pc =3D ch->pc; - int ret; =20 - ret =3D pm_runtime_put(pc->dev); - if (ret < 0) - DRM_DEV_ERROR(pc->dev, "failed to put runtime PM: %d\n", ret); + pm_runtime_put(pc->dev); } =20 static const u32 imx8qxp_pc_bus_output_fmts[] =3D { --- a/drivers/gpu/drm/bridge/imx/imx8qxp-pxl2dpi.c +++ b/drivers/gpu/drm/bridge/imx/imx8qxp-pxl2dpi.c @@ -127,11 +127,8 @@ static void imx8qxp_pxl2dpi_bridge_atomi struct drm_atomic_state *state) { struct imx8qxp_pxl2dpi *p2d =3D bridge->driver_private; - int ret; =20 - ret =3D pm_runtime_put(p2d->dev); - if (ret < 0) - DRM_DEV_ERROR(p2d->dev, "failed to put runtime PM: %d\n", ret); + pm_runtime_put(p2d->dev); =20 if (p2d->companion) p2d->companion->funcs->atomic_disable(p2d->companion, state); --- a/drivers/gpu/drm/imx/dc/dc-crtc.c +++ b/drivers/gpu/drm/imx/dc/dc-crtc.c @@ -300,7 +300,7 @@ dc_crtc_atomic_disable(struct drm_crtc * drm_atomic_get_new_crtc_state(state, crtc); struct dc_drm_device *dc_drm =3D to_dc_drm_device(crtc->dev); struct dc_crtc *dc_crtc =3D to_dc_crtc(crtc); - int idx, ret; + int idx; =20 if (!drm_dev_enter(crtc->dev, &idx)) goto out; @@ -313,16 +313,10 @@ dc_crtc_atomic_disable(struct drm_crtc * dc_fg_disable_clock(dc_crtc->fg); =20 /* request pixel engine power-off as plane is off too */ - ret =3D pm_runtime_put(dc_drm->pe->dev); - if (ret) - dc_crtc_err(crtc, "failed to put DC pixel engine RPM: %d\n", - ret); + pm_runtime_put(dc_drm->pe->dev); =20 /* request display engine power-off when CRTC is disabled */ - ret =3D pm_runtime_put(dc_crtc->de->dev); - if (ret < 0) - dc_crtc_err(crtc, "failed to put DC display engine RPM: %d\n", - ret); + pm_runtime_put(dc_crtc->de->dev); =20 drm_dev_exit(idx); =20 --- a/drivers/gpu/drm/vc4/vc4_hdmi.c +++ b/drivers/gpu/drm/vc4/vc4_hdmi.c @@ -848,7 +848,6 @@ static void vc4_hdmi_encoder_post_crtc_p struct vc4_hdmi *vc4_hdmi =3D encoder_to_vc4_hdmi(encoder); struct drm_device *drm =3D vc4_hdmi->connector.dev; unsigned long flags; - int ret; int idx; =20 mutex_lock(&vc4_hdmi->mutex); @@ -867,9 +866,7 @@ static void vc4_hdmi_encoder_post_crtc_p clk_disable_unprepare(vc4_hdmi->pixel_bvb_clock); clk_disable_unprepare(vc4_hdmi->pixel_clock); =20 - ret =3D pm_runtime_put(&vc4_hdmi->pdev->dev); - if (ret < 0) - drm_err(drm, "Failed to release power domain: %d\n", ret); + pm_runtime_put(&vc4_hdmi->pdev->dev); =20 drm_dev_exit(idx); =20 --- a/drivers/gpu/drm/vc4/vc4_vec.c +++ b/drivers/gpu/drm/vc4/vc4_vec.c @@ -542,7 +542,7 @@ static void vc4_vec_encoder_disable(stru { struct drm_device *drm =3D encoder->dev; struct vc4_vec *vec =3D encoder_to_vc4_vec(encoder); - int idx, ret; + int idx; =20 if (!drm_dev_enter(drm, &idx)) return; @@ -556,17 +556,9 @@ static void vc4_vec_encoder_disable(stru =20 clk_disable_unprepare(vec->clock); =20 - ret =3D pm_runtime_put(&vec->pdev->dev); - if (ret < 0) { - drm_err(drm, "Failed to release power domain: %d\n", ret); - goto err_dev_exit; - } + pm_runtime_put(&vec->pdev->dev); =20 drm_dev_exit(idx); - return; - -err_dev_exit: - drm_dev_exit(idx); } =20 static void vc4_vec_encoder_enable(struct drm_encoder *encoder,