linux-kernel - [PATCH] drm/bridge: it6505: Check power state with it6505->powered in IRQ handler

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Date:   Thu, 27 Jul 2023 18:01:10 +0800
From:   Pin-yen Lin <treapking@...omium.org>
To:     Andrzej Hajda <andrzej.hajda@...el.com>,
        Neil Armstrong <neil.armstrong@...aro.org>,
        Robert Foss <rfoss@...nel.org>,
        Laurent Pinchart <Laurent.pinchart@...asonboard.com>,
        Jonas Karlman <jonas@...boo.se>,
        Jernej Skrabec <jernej.skrabec@...il.com>,
        David Airlie <airlied@...il.com>,
        Daniel Vetter <daniel@...ll.ch>
Cc:     dri-devel@...ts.freedesktop.org, linux-kernel@...r.kernel.org,
        Pin-yen Lin <treapking@...omium.org>
Subject: [PATCH] drm/bridge: it6505: Check power state with it6505->powered in IRQ handler

On system resume, the driver might call it6505_poweron directly if the
runtime PM hasn't been enabled. In such case, pm_runtime_get_if_in_use
will always return 0 because dev->power.runtime_status stays at
RPM_SUSPENDED, and the IRQ will never be handled.

Use it6505->powered from the driver struct fixes this because it always
gets updated when it6505_poweron is called.

Fixes: 5eb9a4314053 ("drm/bridge: it6505: Guard bridge power in IRQ handler")
Signed-off-by: Pin-yen Lin <treapking@...omium.org>

---

 drivers/gpu/drm/bridge/ite-it6505.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/ite-it6505.c b/drivers/gpu/drm/bridge/ite-it6505.c
index 6c2fcd8b8780..2f300f5ca051 100644
--- a/drivers/gpu/drm/bridge/ite-it6505.c
+++ b/drivers/gpu/drm/bridge/ite-it6505.c
@@ -2517,9 +2517,11 @@ static irqreturn_t it6505_int_threaded_handler(int unused, void *data)
 	};
 	int int_status[3], i;
 
-	if (it6505->enable_drv_hold || pm_runtime_get_if_in_use(dev) <= 0)
+	if (it6505->enable_drv_hold || !it6505->powered)
 		return IRQ_HANDLED;
 
+	pm_runtime_get_sync(dev);
+
 	int_status[0] = it6505_read(it6505, INT_STATUS_01);
 	int_status[1] = it6505_read(it6505, INT_STATUS_02);
 	int_status[2] = it6505_read(it6505, INT_STATUS_03);
-- 
2.41.0.487.g6d72f3e995-goog