On some devices bootloader isn't ready to a clamped VDE power, and thus,
machine hangs on a warm reboot (CPU reset). The VDE power partition is
turned ON by default on a cold boot, hence VDE driver should keep power
partition enabled on system's reboot too. This fixes hang on a warm reboot
on a Tegra20 Acer A500 device, which is handy if Embedded Controller
driver is unavailable, i.e. cold reboot can't be performed.
Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
---
drivers/staging/media/tegra-vde/vde.c | 19 +++++++++++++++++++
1 file changed, 19 insertions(+)
diff --git a/drivers/staging/media/tegra-vde/vde.c b/drivers/staging/media/tegra-vde/vde.c
index 85cbbc8f70d3..b64e35b86fb4 100644
--- a/drivers/staging/media/tegra-vde/vde.c
+++ b/drivers/staging/media/tegra-vde/vde.c
@@ -1085,9 +1085,17 @@ static int tegra_vde_remove(struct platform_device *pdev)
struct tegra_vde *vde = platform_get_drvdata(pdev);
struct device *dev = &pdev->dev;
+ pm_runtime_get_sync(dev);
pm_runtime_dont_use_autosuspend(dev);
pm_runtime_disable(dev);
+ /*
+ * Balance RPM state, the VDE power domain is left ON and hardware
+ * is clock-gated. It's safe to reboot machine now.
+ */
+ pm_runtime_put_noidle(dev);
+ clk_disable_unprepare(vde->clk);
+
misc_deregister(&vde->miscdev);
tegra_vde_dmabuf_cache_unmap_all(vde);
@@ -1099,6 +1107,16 @@ static int tegra_vde_remove(struct platform_device *pdev)
return 0;
}
+static void tegra_vde_shutdown(struct platform_device *pdev)
+{
+ /*
+ * On some devices bootloader isn't ready to a power-gated VDE on
+ * a warm-reboot, machine will hang in that case.
+ */
+ if (pm_runtime_status_suspended(&pdev->dev))
+ tegra_vde_runtime_resume(&pdev->dev);
+}
+
static __maybe_unused int tegra_vde_pm_suspend(struct device *dev)
{
struct tegra_vde *vde = dev_get_drvdata(dev);
@@ -1144,6 +1162,7 @@ MODULE_DEVICE_TABLE(of, tegra_vde_of_match);
static struct platform_driver tegra_vde_driver = {
.probe = tegra_vde_probe,
.remove = tegra_vde_remove,
+ .shutdown = tegra_vde_shutdown,
.driver = {
.name = "tegra-vde",
.of_match_table = tegra_vde_of_match,
--
2.26.0
