Hi Tomi,
Thank you for the patch.
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.valkei...@ideasonboard.com>
> ---
> 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);
Then, in the error path,
pm_runtime_dont_use_autosuspend(dev);
pm_runtime_disable(dev);
pm_runtime_put_noidle(dev);
dispc_runtime_suspend(tidss->dispc);
And in remove:
pm_runtime_dont_use_autosuspend(dev);
pm_runtime_disable(dev);
if (!pm_runtime_status_suspended(dev))
dispc_runtime_suspend(tidss->dispc);
pm_runtime_set_suspended(dev);
And yes, runtime PM is a horrible API.
> @@ -215,6 +220,7 @@ static void tidss_remove(struct platform_device *pdev)
> /* If we don't have PM, we need to call suspend manually */
> dispc_runtime_suspend(tidss->dispc);
> #endif
> + pm_runtime_dont_use_autosuspend(dev);
This also needs to be done in the probe error path.
> pm_runtime_disable(dev);
>
> /* devm allocated dispc goes away with the dev so mark it NULL */
>
--
Regards,
Laurent Pinchart
