drm/vc4: hdmi: Switch to pm_runtime_status_suspended

If the controller isn't clocked or its domain powered up, the register
accesses will either stall the CPU or return garbage, respectively.

Thus, we had a warning in our register access function to complain when
that kind of risky accesses were performed.

In order to check the runtime_pm power state, we were using
pm_runtime_active(), but it turns out that it will become active only
once the runtime_resume hook has been executed.

This prevents us from doing any WARN-free register access in our
runtime_resume() implementation, while this is valid.

Let's switch to pm_runtime_status_suspended() instead.

Fixes: 14e193b95604 ("drm/vc4: hdmi: Warn if we access the controller while disabled")
Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Link: https://lore.kernel.org/r/20220613144800.326124-23-maxime@cerno.tech
Signed-off-by: Maxime Ripard <maxime@cerno.tech>

diff --git a/drivers/gpu/drm/vc4/vc4_hdmi_regs.h b/drivers/gpu/drm/vc4/vc4_hdmi_regs.h
index 549cc63..0198de9 100644 (file)
--- a/drivers/gpu/drm/vc4/vc4_hdmi_regs.h
+++ b/drivers/gpu/drm/vc4/vc4_hdmi_regs.h
@@ -423,7 +423,7 @@ static inline u32 vc4_hdmi_read(struct vc4_hdmi *hdmi,
        const struct vc4_hdmi_variant *variant = hdmi->variant;
        void __iomem *base;
 
-       WARN_ON(!pm_runtime_active(&hdmi->pdev->dev));
+       WARN_ON(pm_runtime_status_suspended(&hdmi->pdev->dev));
 
        if (reg >= variant->num_registers) {
                dev_warn(&hdmi->pdev->dev,
@@ -453,7 +453,7 @@ static inline void vc4_hdmi_write(struct vc4_hdmi *hdmi,
 
        lockdep_assert_held(&hdmi->hw_lock);
 
-       WARN_ON(!pm_runtime_active(&hdmi->pdev->dev));
+       WARN_ON(pm_runtime_status_suspended(&hdmi->pdev->dev));
 
        if (reg >= variant->num_registers) {
                dev_warn(&hdmi->pdev->dev,