drm/msm/dp: incorporate pm_runtime framework into DP driver

Currently DP driver is executed independent of PM runtime framework.
This leads msm eDP panel can not being detected by edp_panel driver
during generic_edp_panel_probe() due to AUX DPCD read failed at
edp panel driver. Incorporate PM runtime framework into DP driver so
that host controller's power and clocks are enable/disable through
PM runtime mechanism.  Once PM runtime framework is incorporated into
DP driver, waking up device from power up path is not necessary. Hence
remove it.

After incorporating pm_runtime framework into eDP/DP driver,
dp_pm_suspend() to handle power off both DP phy and controller during
suspend and dp_pm_resume() to handle power on both DP phy and controller
during resume are not necessary. Therefore both dp_pm_suspend() and
dp_pm_resume() are dropped and replace with dp_pm_runtime_suspend() and
dp_pm_runtime_resume() respectively.

Changes in v9:
-- silent compiler warning message at dp_power_init() and dp_power_deinit()
   with W1 flag

Changes in v7:
-- add comments to dp_pm_runtime_resume()
-- add comments to dp_bridge_hpd_enable()
-- delete dp->hpd_state = ST_DISCONNECTED from dp_bridge_hpd_notify()

Changes in v6:
-- delete dp_power_client_deinit(dp->power);
-- remove if (!dp->dp_display.is_edp) condition checkout at plug_handle()
-- remove if (!dp->dp_display.is_edp) condition checkout at unplug_handle()
-- add IRQF_NO_AUTOEN to devm_request_irq()
-- add enable_irq() and disable_irq() to pm_runtime_resume()/suspend()
-- del dp->hpd_state = ST_DISCONNECTED from dp_bridge_hpd_disable()

Changes in v5:
-- remove pm_runtime_put_autosuspend feature, use pm_runtime_put_sync()
-- squash add pm_runtime_force_suspend()/resume() patch into this patch

Changes in v4:
-- reworded commit text to explain why pm_framework is required for
   edp panel
-- reworded commit text to explain autosuspend is choiced
-- delete EV_POWER_PM_GET and PM_EV_POWER_PUT from changes #3
-- delete dp_display_pm_get() and dp_display_pm_Put() from changes #3
-- return value from pm_runtime_resume_and_get() directly
-- check return value of devm_pm_runtime_enable()
-- delete pm_runtime_xxx from dp_display_remove()
-- drop dp_display_host_init() from EV_HPD_INIT_SETUP
-- drop both dp_pm_prepare() and dp_pm_compete() from this change
-- delete ST_SUSPENDED state
-- rewording commit text to add more details regrading the purpose
   of this change

Changes in v3:
-- incorporate removing pm_runtime_xx() from dp_pwer.c to this patch
-- use pm_runtime_resume_and_get() instead of pm_runtime_get()
-- error checking pm_runtime_resume_and_get() return value
-- add EV_POWER_PM_GET and PM_EV_POWER_PUT to handle HPD_GPIO case
-- replace dp_pm_suspend() with pm_runtime_force_suspend()
-- replace dp_pm_resume() with pm_runtime_force_resume()

Signed-off-by: Kuogee Hsieh <quic_khsieh@quicinc.com>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/570073/
Link: https://lore.kernel.org/r/1701472789-25951-6-git-send-email-quic_khsieh@quicinc.com
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

1 files changed, 5 insertions, 0 deletions

diff --git a/drivers/gpu/drm/msm/dp/dp_aux.c b/drivers/gpu/drm/msm/dp/dp_aux.c
index 8e3b677f35e6..10b6eeb7bebf 100644
--- a/drivers/gpu/drm/msm/dp/dp_aux.c
+++ b/drivers/gpu/drm/msm/dp/dp_aux.c
@@ -291,6 +291,10 @@ static ssize_t dp_aux_transfer(struct drm_dp_aux *dp_aux,
 		return -EINVAL;
 	}
 
+	ret = pm_runtime_resume_and_get(dp_aux->dev);
+	if (ret)
+		return  ret;
+
 	mutex_lock(&aux->mutex);
 	if (!aux->initted) {
 		ret = -EIO;
@@ -364,6 +368,7 @@ static ssize_t dp_aux_transfer(struct drm_dp_aux *dp_aux,
 
 exit:
 	mutex_unlock(&aux->mutex);
+	pm_runtime_put_sync(dp_aux->dev);
 
 	return ret;
 }