From 7a9696dbad6be801602dc00ccbbe44b8ae46e65b Mon Sep 17 00:00:00 2001 From: Douglas Anderson Date: Thu, 21 Sep 2023 12:26:52 -0700 Subject: [PATCH] drm/exynos: Call drm_atomic_helper_shutdown() at shutdown/unbind time [ Upstream commit 16ac5b21b31b439f03cdf44c153c5f5af94fb3eb ] 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 Reviewed-by: Maxime Ripard Signed-off-by: Douglas Anderson Tested-by: Marek Szyprowski Reviewed-by: Marek Szyprowski Signed-off-by: Inki Dae Signed-off-by: Sasha Levin --- drivers/gpu/drm/exynos/exynos_drm_drv.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/gpu/drm/exynos/exynos_drm_drv.c b/drivers/gpu/drm/exynos/exynos_drm_drv.c index 8399256..5380fb6 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_drv.c +++ b/drivers/gpu/drm/exynos/exynos_drm_drv.c @@ -300,6 +300,7 @@ err_mode_config_cleanup: drm_mode_config_cleanup(drm); exynos_drm_cleanup_dma(drm); kfree(private); + dev_set_drvdata(dev, NULL); err_free_drm: drm_dev_put(drm); @@ -313,6 +314,7 @@ static void exynos_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); drm_mode_config_cleanup(drm); @@ -350,9 +352,18 @@ static int exynos_drm_platform_remove(struct platform_device *pdev) return 0; } +static void exynos_drm_platform_shutdown(struct platform_device *pdev) +{ + struct drm_device *drm = platform_get_drvdata(pdev); + + if (drm) + drm_atomic_helper_shutdown(drm); +} + static struct platform_driver exynos_drm_platform_driver = { .probe = exynos_drm_platform_probe, .remove = exynos_drm_platform_remove, + .shutdown = exynos_drm_platform_shutdown, .driver = { .name = "exynos-drm", .pm = &exynos_drm_pm_ops, -- 2.7.4