From 02680d71dea89b3e58015cf726f5e175730e1002 Mon Sep 17 00:00:00 2001
From: Douglas Anderson <dianders@chromium.org>
Date: Fri, 1 Sep 2023 16:41:24 -0700
Subject: [PATCH] drm/imx/ipuv3: Call drm_atomic_helper_shutdown() at
shutdown/unbind time
Based on grepping through the source code this driver appears to be
missing a call to drm_atomic_helper_shutdown() at system shutdown time
and at driver unbind time. Among other things, this means that if a
panel is in use that it won't be cleanly powered off at system
shutdown time.
The fact that we should call drm_atomic_helper_shutdown() in the case
of OS shutdown/restart and at driver remove (or unbind) time comes
straight out of the kernel doc "driver instance overview" in
drm_drv.c.
A few notes about this fix:
- When adding drm_atomic_helper_shutdown() to the unbind path, I added
it after drm_kms_helper_poll_fini() since that's when other drivers
seemed to have it.
- Technically with a previous patch, ("drm/atomic-helper:
drm_atomic_helper_shutdown(NULL) should be a noop"), we don't
actually need to check to see if our "drm" pointer is NULL before
calling drm_atomic_helper_shutdown(). We'll leave the "if" test in,
though, so that this patch can land without any dependencies. It
could potentially be removed later.
- This patch also makes sure to set the drvdata to NULL in the case of
bind errors to make sure that shutdown can't access freed data.
Suggested-by: Maxime Ripard <mripard@kernel.org>
Reviewed-by: Maxime Ripard <mripard@kernel.org>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230901164111.RFT.13.I0a9940ff6f387d6acf4e71d8c7dbaff8c42e3aaa@changeid
---
drivers/gpu/drm/imx/ipuv3/imx-drm-core.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/drivers/gpu/drm/imx/ipuv3/imx-drm-core.c b/drivers/gpu/drm/imx/ipuv3/imx-drm-core.c
index 352fa31ab4ed7..4cfabcf7375a9 100644
--- a/drivers/gpu/drm/imx/ipuv3/imx-drm-core.c
+++ b/drivers/gpu/drm/imx/ipuv3/imx-drm-core.c
@@ -257,6 +257,7 @@ static int imx_drm_bind(struct device *dev)
drm_kms_helper_poll_fini(drm);
component_unbind_all(drm->dev, drm);
err_kms:
+ dev_set_drvdata(dev, NULL);
drm_dev_put(drm);
return ret;
@@ -269,6 +270,7 @@ static void imx_drm_unbind(struct device *dev)
drm_dev_unregister(drm);
drm_kms_helper_poll_fini(drm);
+ drm_atomic_helper_shutdown(drm);
component_unbind_all(drm->dev, drm);
@@ -297,6 +299,11 @@ static void imx_drm_platform_remove(struct platform_device *pdev)
component_master_del(&pdev->dev, &imx_drm_ops);
}
+static void imx_drm_platform_shutdown(struct platform_device *pdev)
+{
+ drm_atomic_helper_shutdown(platform_get_drvdata(pdev));
+}
+
#ifdef CONFIG_PM_SLEEP
static int imx_drm_suspend(struct device *dev)
{
@@ -324,6 +331,7 @@ MODULE_DEVICE_TABLE(of, imx_drm_dt_ids);
static struct platform_driver imx_drm_pdrv = {
.probe = imx_drm_platform_probe,
.remove_new = imx_drm_platform_remove,
+ .shutdown = imx_drm_platform_shutdown,
.driver = {
.name = "imx-drm",
.pm = &imx_drm_pm_ops,
--
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