drm/i915/display: Use device parameters instead of module in I915_STATE_WARN

Also make module parameter as non writable.
Signed-off-by: Jouni Högander <jouni.hogander@intel.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231024124109.384973-21-jouni.hogander@intel.com

drivers/gpu/drm/i915/display/intel_display.h

@@ -552,7 +552,7 @@ bool assert_port_valid(struct drm_i915_private *i915, enum port port);
 	struct drm_device *drm = &(__i915)->drm;			\
 	int __ret_warn_on = !!(condition);				\
 	if (unlikely(__ret_warn_on))					\
-		if (!drm_WARN(drm, i915_modparams.verbose_state_checks, format)) \
+		if (!drm_WARN(drm, __i915->params.verbose_state_checks, format)) \
 			drm_err(drm, format);				\
 	unlikely(__ret_warn_on);					\
 })

drivers/gpu/drm/i915/i915_params.c

@@ -93,8 +93,7 @@ i915_param_named(mmio_debug, int, 0400,
 	"Enable the MMIO debug code for the first N failures (default: off). "
 	"This may negatively affect performance.");
 
-/* Special case writable file */
-i915_param_named(verbose_state_checks, bool, 0600,
+i915_param_named(verbose_state_checks, bool, 0400,
 	"Enable verbose logs (ie. WARN_ON()) in case of unexpected hw state conditions.");
 
 i915_param_named_unsafe(nuclear_pageflip, bool, 0400,