From 0bab51e122cbb56a29847c4de87bf5088b3bb771 Mon Sep 17 00:00:00 2001
From: Maxime Ripard <maxime@cerno.tech>
Date: Thu, 19 Aug 2021 15:59:27 +0200
Subject: drm/vc4: hdmi: Make sure the controller is powered up during bind
Git-commit: 9c6e4f6ed1d61d5f46946e5c151ceb279eedadb1
Patch-mainline: v5.17-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225
In the bind hook, we actually need the device to have the HSM clock
running during the final part of the display initialisation where we
reset the controller and initialise the CEC component.
Failing to do so will result in a complete, silent, hang of the CPU.
Fixes: 411efa18e4b0 ("drm/vc4: hdmi: Move the HSM clock enable to runtime_pm")
Link: https://patchwork.freedesktop.org/patch/msgid/20210819135931.895976-3-maxime@cerno.tech
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/vc4/vc4_hdmi.c | 17 +++++++++++++++--
1 file changed, 15 insertions(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
index f7e48bc6cb11..29ee9264b087 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -2191,6 +2191,18 @@ static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data)
if (ret)
goto err_put_ddc;
+ /*
+ * 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);
+ if (ret)
+ goto err_put_ddc;
+
+ pm_runtime_get_noresume(dev);
+ pm_runtime_set_active(dev);
+ pm_runtime_enable(dev);
+
if (vc4_hdmi->variant->reset)
vc4_hdmi->variant->reset(vc4_hdmi);
@@ -2202,8 +2214,6 @@ static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data)
clk_prepare_enable(vc4_hdmi->pixel_bvb_clock);
}
- pm_runtime_enable(dev);
-
drm_simple_encoder_init(drm, encoder, DRM_MODE_ENCODER_TMDS);
drm_encoder_helper_add(encoder, &vc4_hdmi_encoder_helper_funcs);
@@ -2227,6 +2237,8 @@ static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data)
vc4_hdmi_debugfs_regs,
vc4_hdmi);
+ pm_runtime_put_sync(dev);
+
return 0;
err_free_cec:
@@ -2237,6 +2249,7 @@ static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data)
vc4_hdmi_connector_destroy(&vc4_hdmi->connector);
err_destroy_encoder:
drm_encoder_cleanup(encoder);
+ pm_runtime_put_sync(dev);
pm_runtime_disable(dev);
err_put_ddc:
put_device(&vc4_hdmi->ddc->dev);
--
2.38.1