[PATCH 5.19 01/72] drm/vc4: hdmi: Rework power up

Greg Kroah-Hartman
2022-09-02T13:36:15Z

From: Maxime Ripard <maxime@cerno.tech>

commit 258e483a4d5e97a6a8caa74381ddc1f395ac1c71 upstream.

The current code tries to handle the case where CONFIG_PM isn't selected
by first calling our runtime_resume implementation and then properly
report the power state to the runtime_pm core.

This allows to have a functionning device even if pm_runtime_get_*
functions are nops.

However, the device power state if CONFIG_PM is enabled is
RPM_SUSPENDED, and thus our vc4_hdmi_write() and vc4_hdmi_read() calls
in the runtime_pm hooks will now report a warning since the device might
not be properly powered.

Even more so, we need CONFIG_PM enabled since the previous RaspberryPi
have a power domain that needs to be powered up for the HDMI controller
to be usable.

The previous patch has created a dependency on CONFIG_PM, now we can
just assume it's there and only call pm_runtime_resume_and_get() to make
sure our device is powered in bind.

Link: https://lore.kernel.org/r/20220629123510.1915022-39-maxime@cerno.tech
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
(cherry picked from commit 53565c28e6af2cef6bbf438c34250135e3564459)
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Cc: "Sudip Mukherjee (Codethink)" <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/gpu/drm/vc4/vc4_hdmi.c | 15 +++++++--------
1 file changed, 7 insertions(+), 8 deletions(-)

--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -2992,17 +2992,15 @@ static int vc4_hdmi_bind(struct device *
vc4_hdmi->disable_4kp60 = true;
}

+ pm_runtime_enable(dev);
+
/*
- * We need to have the device powered up at this point to call
- * our reset hook and for the CEC init.
+ * We need to have the device powered up at this point to call
+ * our reset hook and for the CEC init.
*/
- ret = vc4_hdmi_runtime_resume(dev);
+ ret = pm_runtime_resume_and_get(dev);
if (ret)
- goto err_put_ddc;
-
- pm_runtime_get_noresume(dev);
- pm_runtime_set_active(dev);
- pm_runtime_enable(dev);
+ goto err_disable_runtime_pm;

if ((of_device_is_compatible(dev->of_node, "brcm,bcm2711-hdmi0") ||
of_device_is_compatible(dev->of_node, "brcm,bcm2711-hdmi1")) &&
@@ -3048,6 +3046,7 @@ err_destroy_conn:
err_destroy_encoder:
drm_encoder_cleanup(encoder);
pm_runtime_put_sync(dev);
+err_disable_runtime_pm:
pm_runtime_disable(dev);
err_put_ddc:
put_device(&vc4_hdmi->ddc->dev);