Hi Tomi,
CC'ing Sakari for his expertise on runtime PM (I think he will soon
start wishing he would be ignorant in this area).
On Thu, Nov 02, 2023 at 08:34:45AM +0200, Tomi Valkeinen wrote:
On 01/11/2023 15:54, Laurent Pinchart wrote:
On Wed, Nov 01, 2023 at 11:17:39AM +0200, Tomi Valkeinen wrote:
Use runtime PM autosuspend feature, with 1s timeout, to avoid
unnecessary suspend-resume cycles when, e.g. the userspace temporarily
turns off the crtcs when configuring the outputs.
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@xxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/tidss/tidss_drv.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/tidss/tidss_drv.c b/drivers/gpu/drm/tidss/tidss_drv.c
index f403db11b846..64914331715a 100644
--- a/drivers/gpu/drm/tidss/tidss_drv.c
+++ b/drivers/gpu/drm/tidss/tidss_drv.c
@@ -43,7 +43,9 @@ void tidss_runtime_put(struct tidss_device *tidss)
dev_dbg(tidss->dev, "%s\n", __func__);
- r = pm_runtime_put_sync(tidss->dev);
+ pm_runtime_mark_last_busy(tidss->dev);
+
+ r = pm_runtime_put_autosuspend(tidss->dev);
WARN_ON(r < 0);
}
@@ -144,6 +146,9 @@ static int tidss_probe(struct platform_device *pdev)
pm_runtime_enable(dev);
+ pm_runtime_set_autosuspend_delay(dev, 1000);
+ pm_runtime_use_autosuspend(dev);
+
#ifndef CONFIG_PM
/* If we don't have PM, we need to call resume manually */
dispc_runtime_resume(tidss->dispc);
By the way, there's a way to handle this without any ifdef:
dispc_runtime_resume(tidss->dispc);
pm_runtime_set_active(dev);
pm_runtime_get_noresume(dev);
pm_runtime_enable(dev);
pm_runtime_set_autosuspend_delay(dev, 1000);
pm_runtime_use_autosuspend(dev);
I'm not sure I follow what you are trying to do here. The call to
dispc_runtime_resume() would crash if we have PM, as the HW would not be
enabled at that point.
Isn't dispc_runtime_resume() meant to enable the hardware ?
The idea is to enable the hardware, then enable runtime PM, and tell the
runtime PM framework that the device is enabled. If CONFIG_PM is not
set, the RPM calls will be no-ops, and the device will stay enable. If
CONFIG_PM is set, the device will be enabled, and will get disabled at
end of probe by a call to pm_runtime_put_autosuspend().