Re: [PATCH v4 7/8] drm/msm/dp: add pm_runtime_force_suspend()/resume()
From: Kuogee Hsieh
Date: Tue Oct 03 2023 - 12:44:22 EST
On 9/27/2023 3:00 PM, Dmitry Baryshkov wrote:
On Wed, 27 Sept 2023 at 23:54, Kuogee Hsieh <quic_khsieh@xxxxxxxxxxx> wrote:
After incorporated pm_runtime framework into eDP/DP driver, the
incorporating
original 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 since
those function are replaced by dp_pm_runtime_suspend() and
dp_pm_runtime_resume() through pm runtime framework.
Therefore add pm framework provides functions,
pm_runtime_force_suspend()/resume() to complete incorporating pm
runtime framework into DP driver.
Changes in v4:
-- 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:
-- 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@xxxxxxxxxxx>
---
drivers/gpu/drm/msm/dp/dp_display.c | 113 ++----------------------------------
1 file changed, 5 insertions(+), 108 deletions(-)
diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
index 9158a2c..711d262 100644
--- a/drivers/gpu/drm/msm/dp/dp_display.c
+++ b/drivers/gpu/drm/msm/dp/dp_display.c
@@ -49,7 +49,6 @@ enum {
ST_CONNECTED,
ST_DISCONNECT_PENDING,
ST_DISPLAY_OFF,
- ST_SUSPENDED,
};
enum {
@@ -560,7 +559,7 @@ static int dp_hpd_plug_handle(struct dp_display_private *dp, u32 data)
drm_dbg_dp(dp->drm_dev, "Before, type=%d hpd_state=%d\n",
dp->dp_display.connector_type, state);
- if (state == ST_DISPLAY_OFF || state == ST_SUSPENDED) {
+ if (state == ST_DISPLAY_OFF) {
mutex_unlock(&dp->event_mutex);
return 0;
}
@@ -674,7 +673,7 @@ static int dp_irq_hpd_handle(struct dp_display_private *dp, u32 data)
drm_dbg_dp(dp->drm_dev, "Before, type=%d hpd_state=%d\n",
dp->dp_display.connector_type, state);
- if (state == ST_DISPLAY_OFF || state == ST_SUSPENDED) {
+ if (state == ST_DISPLAY_OFF) {
mutex_unlock(&dp->event_mutex);
return 0;
}
@@ -1321,110 +1320,10 @@ static int dp_pm_runtime_resume(struct device *dev)
return 0;
}
-static int dp_pm_resume(struct device *dev)
-{
- struct platform_device *pdev = to_platform_device(dev);
- struct msm_dp *dp_display = platform_get_drvdata(pdev);
- struct dp_display_private *dp;
- int sink_count = 0;
-
- dp = container_of(dp_display, struct dp_display_private, dp_display);
-
- mutex_lock(&dp->event_mutex);
-
- drm_dbg_dp(dp->drm_dev,
- "Before, type=%d core_inited=%d phy_inited=%d power_on=%d\n",
- dp->dp_display.connector_type, dp->core_initialized,
- dp->phy_initialized, dp_display->power_on);
-
- /* start from disconnected state */
- dp->hpd_state = ST_DISCONNECTED;
-
- /* turn on dp ctrl/phy */
- dp_display_host_init(dp);
-
- if (dp_display->is_edp)
- dp_catalog_ctrl_hpd_enable(dp->catalog);
-
- if (dp_catalog_link_is_connected(dp->catalog)) {
- /*
- * set sink to normal operation mode -- D0
- * before dpcd read
- */
- dp_display_host_phy_init(dp);
- dp_link_psm_config(dp->link, &dp->panel->link_info, false);
- sink_count = drm_dp_read_sink_count(dp->aux);
- if (sink_count < 0)
- sink_count = 0;
-
- dp_display_host_phy_exit(dp);
- }
-
- dp->link->sink_count = sink_count;
- /*
- * can not declared display is connected unless
- * HDMI cable is plugged in and sink_count of
- * dongle become 1
- * also only signal audio when disconnected
- */
- if (dp->link->sink_count) {
- dp->dp_display.link_ready = true;
- } else {
- dp->dp_display.link_ready = false;
- dp_display_handle_plugged_change(dp_display, false);
- }
-
- drm_dbg_dp(dp->drm_dev,
- "After, type=%d sink=%d conn=%d core_init=%d phy_init=%d power=%d\n",
- dp->dp_display.connector_type, dp->link->sink_count,
- dp->dp_display.link_ready, dp->core_initialized,
- dp->phy_initialized, dp_display->power_on);
-
- mutex_unlock(&dp->event_mutex);
-
- return 0;
-}
-
-static int dp_pm_suspend(struct device *dev)
-{
- struct platform_device *pdev = to_platform_device(dev);
- struct msm_dp *dp_display = platform_get_drvdata(pdev);
- struct dp_display_private *dp;
-
- dp = container_of(dp_display, struct dp_display_private, dp_display);
-
- mutex_lock(&dp->event_mutex);
-
- drm_dbg_dp(dp->drm_dev,
- "Before, type=%d core_inited=%d phy_inited=%d power_on=%d\n",
- dp->dp_display.connector_type, dp->core_initialized,
- dp->phy_initialized, dp_display->power_on);
-
- /* mainlink enabled */
- if (dp_power_clk_status(dp->power, DP_CTRL_PM))
- dp_ctrl_off_link_stream(dp->ctrl);
-
- dp_display_host_phy_exit(dp);
I was under the impression that dp_pm_runtime_suspend / _resume
functions perform phy init/exit only in eDP cases. Can we really drop
the main suspend/resume functions?
yes on eDP case since it is embedded.
for external DP case, there are two steps
step 1: enable DP controller's hpd block and start waiting for hpd
interrupts at dp_display_hpd_enable()
step 2: at plugin interrupts, dp_display_host_phy_init()
step 3: at unplug interrupt: dp_bridge_atomic_post_disable()
dp_display_host_phy_exi()
at runtime, there is loop between step 2 and step 3
step 4: disable DP controller's hpd block
-
- /* host_init will be called at pm_resume */
- dp_display_host_deinit(dp);
-
- dp->hpd_state = ST_SUSPENDED;
-
- drm_dbg_dp(dp->drm_dev,
- "After, type=%d core_inited=%d phy_inited=%d power_on=%d\n",
- dp->dp_display.connector_type, dp->core_initialized,
- dp->phy_initialized, dp_display->power_on);
-
- mutex_unlock(&dp->event_mutex);
-
- return 0;
-}
-
static const struct dev_pm_ops dp_pm_ops = {
SET_RUNTIME_PM_OPS(dp_pm_runtime_suspend, dp_pm_runtime_resume, NULL)
- .suspend = dp_pm_suspend,
- .resume = dp_pm_resume,
+ SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+ pm_runtime_force_resume)
};
static struct platform_driver dp_display_driver = {
@@ -1658,9 +1557,6 @@ void dp_bridge_atomic_post_disable(struct drm_bridge *drm_bridge,
dp_display = container_of(dp, struct dp_display_private, dp_display);
- if (dp->is_edp)
- dp_hpd_unplug_handle(dp_display, 0);
Why?
dp_hpd_unplug_handle() does not tear down phy.
Therefore eDP does not need to call unplug handle.
-
mutex_lock(&dp_display->event_mutex);
state = dp_display->hpd_state;
@@ -1748,6 +1644,7 @@ void dp_bridge_hpd_disable(struct drm_bridge *bridge)
dp_catalog_ctrl_hpd_disable(dp->catalog);
dp_display->internal_hpd = false;
+ dp->hpd_state = ST_DISCONNECTED;
Why? We have only disabled sending of the HPD events. The dongle might
still be connected.
dp_bridge_hpd_disable() disable dp controller hpd block (no more hpd
interrupt will be received).
dp_bridge_hpd_disable() should happen after DP main link had been teared
down already.
Therefore hpd_state need to be in default state so that next plugin
handle will be start with correct state.
pm_runtime_mark_last_busy(&dp->pdev->dev);
pm_runtime_put_autosuspend(&dp->pdev->dev);
--
2.7.4
--
With best wishes
Dmitry