From 14e193b95604182a338e3721385e3d8a56d3c5a8 Mon Sep 17 00:00:00 2001 From: Maxime Ripard Date: Thu, 19 Aug 2021 15:59:31 +0200 Subject: [PATCH] drm/vc4: hdmi: Warn if we access the controller while disabled We've had many silent hangs where the kernel would look like it just stalled due to the access to one of the HDMI registers while the controller was disabled. Add a warning if we're about to do that so that it's at least not silent anymore. Reviewed-by: Dave Stevenson Signed-off-by: Maxime Ripard Link: https://patchwork.freedesktop.org/patch/msgid/20210819135931.895976-7-maxime@cerno.tech --- drivers/gpu/drm/vc4/vc4_hdmi_regs.h | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/gpu/drm/vc4/vc4_hdmi_regs.h b/drivers/gpu/drm/vc4/vc4_hdmi_regs.h index 19d2fdc446bc..99dde6e06a37 100644 --- a/drivers/gpu/drm/vc4/vc4_hdmi_regs.h +++ b/drivers/gpu/drm/vc4/vc4_hdmi_regs.h @@ -1,6 +1,8 @@ #ifndef _VC4_HDMI_REGS_H_ #define _VC4_HDMI_REGS_H_ +#include + #include "vc4_hdmi.h" #define VC4_HDMI_PACKET_STRIDE 0x24 @@ -412,6 +414,8 @@ 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)); + if (reg >= variant->num_registers) { dev_warn(&hdmi->pdev->dev, "Invalid register ID %u\n", reg); @@ -438,6 +442,8 @@ static inline void vc4_hdmi_write(struct vc4_hdmi *hdmi, const struct vc4_hdmi_variant *variant = hdmi->variant; void __iomem *base; + WARN_ON(!pm_runtime_active(&hdmi->pdev->dev)); + if (reg >= variant->num_registers) { dev_warn(&hdmi->pdev->dev, "Invalid register ID %u\n", reg); -- 2.34.1