1 files changed, 59 insertions, 0 deletions
diff --git a/drivers/gpu/drm/sysfb/drm_sysfb.c b/drivers/gpu/drm/sysfb/drm_sysfb.c
new file mode 100644
index 000000000000..fbfb37d0fae1
--- /dev/null
+++ b/drivers/gpu/drm/sysfb/drm_sysfb.c
@@ -0,0 +1,59 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/export.h>
+#include <linux/limits.h>
+#include <linux/minmax.h>
+#include <linux/module.h>
+
+#include <drm/drm_print.h>
+
+#include "drm_sysfb_helper.h"
+
+int drm_sysfb_get_validated_int(struct drm_device *dev, const char *name,
+				u64 value, u32 max)
+{
+	if (value > min(max, INT_MAX)) {
+		drm_warn(dev, "%s of %llu exceeds maximum of %u\n", name, value, max);
+		return -EINVAL;
+	}
+	return value;
+}
+EXPORT_SYMBOL(drm_sysfb_get_validated_int);
+
+int drm_sysfb_get_validated_int0(struct drm_device *dev, const char *name,
+				 u64 value, u32 max)
+{
+	if (!value) {
+		drm_warn(dev, "%s of 0 not allowed\n", name);
+		return -EINVAL;
+	}
+	return drm_sysfb_get_validated_int(dev, name, value, max);
+}
+EXPORT_SYMBOL(drm_sysfb_get_validated_int0);
+
+const struct drm_format_info *drm_sysfb_get_format(struct drm_device *dev,
+						   const struct drm_sysfb_format *formats,
+						   size_t nformats,
+						   const struct pixel_format *pixel)
+{
+	const struct drm_format_info *format = NULL;
+	size_t i;
+
+	for (i = 0; i < nformats; ++i) {
+		const struct drm_sysfb_format *f = &formats[i];
+
+		if (pixel_format_equal(pixel, &f->pixel)) {
+			format = drm_format_info(f->fourcc);
+			break;
+		}
+	}
+
+	if (!format)
+		drm_warn(dev, "No compatible color format found\n");
+
+	return format;
+}
+EXPORT_SYMBOL(drm_sysfb_get_format);
+
+MODULE_DESCRIPTION("Helpers for DRM sysfb drivers");
+MODULE_LICENSE("GPL");