diff options
| author | Gustavo Kenji Mendonça Kaneko <kaneko.dev@pm.me> | 2026-06-09 13:08:33 +0000 |
|---|---|---|
| committer | Liviu Dudau <liviu.dudau@arm.com> | 2026-06-30 15:26:54 +0100 |
| commit | 6502eb8cfcd6f7bc5f1f8b73ee524112bd93319d (patch) | |
| tree | 40714f09ab8c7cf22c29524c50cf17c5a54ae266 /drivers | |
| parent | 46f715a16989f4e7bbbc2eb41447051874b027f3 (diff) | |
drm/arm/komeda: fix error handling for clk_prepare_enable() and callers
komeda_dev_resume() calls clk_prepare_enable() without checking the
return value. If the clock fails to enable, the function returns 0
(success) while IRQs are enabled and IOMMU is connected on potentially
unclocked hardware, causing undefined behavior on resume.
Propagate the error from clk_prepare_enable() and fix all call sites
in komeda_drv.c that previously ignored the return value of
komeda_dev_resume():
- komeda_platform_probe(): if resume fails, jump to err_destroy_mdev
(skipping the suspend call, since the clock was never enabled)
- komeda_pm_resume(): propagate the error and skip
drm_mode_config_helper_resume() on failure
This issue was found by code review without access to Komeda hardware.
Signed-off-by: Gustavo Kenji Mendonça Kaneko <kaneko.dev@pm.me>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com>
Link: https://patch.msgid.link/20260609130828.1066038-1-kaneko.dev@pm.me
Signed-off-by: Liviu Dudau <liviu.dudau@arm.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/gpu/drm/arm/display/komeda/komeda_dev.c | 6 | ||||
| -rw-r--r-- | drivers/gpu/drm/arm/display/komeda/komeda_drv.c | 14 |
2 files changed, 14 insertions, 6 deletions
diff --git a/drivers/gpu/drm/arm/display/komeda/komeda_dev.c b/drivers/gpu/drm/arm/display/komeda/komeda_dev.c index 5ba62e637a61..9aad1d1d28ec 100644 --- a/drivers/gpu/drm/arm/display/komeda/komeda_dev.c +++ b/drivers/gpu/drm/arm/display/komeda/komeda_dev.c @@ -313,7 +313,11 @@ void komeda_dev_destroy(struct komeda_dev *mdev) int komeda_dev_resume(struct komeda_dev *mdev) { - clk_prepare_enable(mdev->aclk); + int err; + + err = clk_prepare_enable(mdev->aclk); + if (err) + return err; mdev->funcs->enable_irq(mdev); diff --git a/drivers/gpu/drm/arm/display/komeda/komeda_drv.c b/drivers/gpu/drm/arm/display/komeda/komeda_drv.c index 4bb5f250e95e..67fffab018ae 100644 --- a/drivers/gpu/drm/arm/display/komeda/komeda_drv.c +++ b/drivers/gpu/drm/arm/display/komeda/komeda_drv.c @@ -74,8 +74,11 @@ static int komeda_platform_probe(struct platform_device *pdev) } pm_runtime_enable(dev); - if (!pm_runtime_enabled(dev)) - komeda_dev_resume(mdrv->mdev); + if (!pm_runtime_enabled(dev)) { + err = komeda_dev_resume(mdrv->mdev); + if (err) + goto err_destroy_mdev; + } mdrv->kms = komeda_kms_attach(mdrv->mdev); if (IS_ERR(mdrv->kms)) { @@ -93,7 +96,7 @@ destroy_mdev: pm_runtime_disable(dev); else komeda_dev_suspend(mdrv->mdev); - +err_destroy_mdev: komeda_dev_destroy(mdrv->mdev); free_mdrv: @@ -140,11 +143,12 @@ static int __maybe_unused komeda_pm_suspend(struct device *dev) static int __maybe_unused komeda_pm_resume(struct device *dev) { struct komeda_drv *mdrv = dev_get_drvdata(dev); + int err = 0; if (!pm_runtime_status_suspended(dev)) - komeda_dev_resume(mdrv->mdev); + err = komeda_dev_resume(mdrv->mdev); - return drm_mode_config_helper_resume(&mdrv->kms->base); + return err ? err : drm_mode_config_helper_resume(&mdrv->kms->base); } static const struct dev_pm_ops komeda_pm_ops = { |