diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
index f632ca05960e..92a5cd6ff6b1 100644
--- a/drivers/gpu/drm/drm_connector.c
+++ b/drivers/gpu/drm/drm_connector.c
@@ -2377,7 +2377,7 @@ EXPORT_SYMBOL(drm_mode_put_tile_group);
  * tile group or NULL if not found.
  */
 struct drm_tile_group *drm_mode_get_tile_group(struct drm_device *dev,
-					       char topology[8])
+					       const u8 topology[8])
 {
 	struct drm_tile_group *tg;
 	int id;
@@ -2407,7 +2407,7 @@ EXPORT_SYMBOL(drm_mode_get_tile_group);
  * new tile group or NULL.
  */
 struct drm_tile_group *drm_mode_create_tile_group(struct drm_device *dev,
-						  char topology[8])
+						  const u8 topology[8])
 {
 	struct drm_tile_group *tg;
 	int ret;
diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
index fd9b724067a7..8e76efe1654d 100644
--- a/drivers/gpu/drm/drm_edid.c
+++ b/drivers/gpu/drm/drm_edid.c
@@ -88,7 +88,7 @@
 
 struct detailed_mode_closure {
 	struct drm_connector *connector;
-	struct edid *edid;
+	const struct edid *edid;
 	bool preferred;
 	u32 quirks;
 	int modes;
@@ -1584,8 +1584,8 @@ MODULE_PARM_DESC(edid_fixup,
 		 "Minimum number of valid EDID header bytes (0-8, default 6)");
 
 static void drm_get_displayid(struct drm_connector *connector,
-			      struct edid *edid);
-static int validate_displayid(u8 *displayid, int length, int idx);
+			      const struct edid *edid);
+static int validate_displayid(const u8 *displayid, int length, int idx);
 
 static int drm_edid_block_checksum(const u8 *raw_edid)
 {
@@ -2207,41 +2207,41 @@ static bool is_detailed_timing_descriptor(const u8 d[18])
 	return d[0] != 0x00 || d[1] != 0x00;
 }
 
-typedef void detailed_cb(struct detailed_timing *timing, void *closure);
+typedef void detailed_cb(const struct detailed_timing *timing, void *closure);
 
 static void
-cea_for_each_detailed_block(u8 *ext, detailed_cb *cb, void *closure)
+cea_for_each_detailed_block(const u8 *ext, detailed_cb *cb, void *closure)
 {
 	int i, n;
 	u8 d = ext[0x02];
-	u8 *det_base = ext + d;
+	const u8 *det_base = ext + d;
 
 	if (d < 4 || d > 127)
 		return;
 
 	n = (127 - d) / 18;
 	for (i = 0; i < n; i++)
-		cb((struct detailed_timing *)(det_base + 18 * i), closure);
+		cb((const struct detailed_timing *)(det_base + 18 * i), closure);
 }
 
 static void
-vtb_for_each_detailed_block(u8 *ext, detailed_cb *cb, void *closure)
+vtb_for_each_detailed_block(const u8 *ext, detailed_cb *cb, void *closure)
 {
 	unsigned int i, n = min((int)ext[0x02], 6);
-	u8 *det_base = ext + 5;
+	const u8 *det_base = ext + 5;
 
 	if (ext[0x01] != 1)
 		return; /* unknown version */
 
 	for (i = 0; i < n; i++)
-		cb((struct detailed_timing *)(det_base + 18 * i), closure);
+		cb((const struct detailed_timing *)(det_base + 18 * i), closure);
 }
 
 static void
-drm_for_each_detailed_block(u8 *raw_edid, detailed_cb *cb, void *closure)
+drm_for_each_detailed_block(const u8 *raw_edid, detailed_cb *cb, void *closure)
 {
+	const struct edid *edid = (struct edid *)raw_edid;
 	int i;
-	struct edid *edid = (struct edid *)raw_edid;
 
 	if (edid == NULL)
 		return;
@@ -2250,7 +2250,7 @@ drm_for_each_detailed_block(u8 *raw_edid, detailed_cb *cb, void *closure)
 		cb(&(edid->detailed_timings[i]), closure);
 
 	for (i = 1; i <= raw_edid[0x7e]; i++) {
-		u8 *ext = raw_edid + (i * EDID_LENGTH);
+		const u8 *ext = raw_edid + (i * EDID_LENGTH);
 		switch (*ext) {
 		case CEA_EXT:
 			cea_for_each_detailed_block(ext, cb, closure);
@@ -2264,81 +2264,105 @@ drm_for_each_detailed_block(u8 *raw_edid, detailed_cb *cb, void *closure)
 	}
 }
 
+struct bool_closure {
+	bool ret;
+};
+
 static void
-is_rb(struct detailed_timing *t, void *data)
+is_rb(const struct detailed_timing *t, void *c)
 {
-	u8 *r = (u8 *)t;
+	struct bool_closure *closure = c;
+	const u8 *r = (const u8 *)t;
 
 	if (!is_display_descriptor(r, EDID_DETAIL_MONITOR_RANGE))
 		return;
 
 	if (r[15] & 0x10)
-		*(bool *)data = true;
+		closure->ret = true;
 }
 
 /* EDID 1.4 defines this explicitly.  For EDID 1.3, we guess, badly. */
 static bool
-drm_monitor_supports_rb(struct edid *edid)
+drm_monitor_supports_rb(const struct edid *edid)
 {
 	if (edid->revision >= 4) {
-		bool ret = false;
-		drm_for_each_detailed_block((u8 *)edid, is_rb, &ret);
-		return ret;
+		struct bool_closure closure = {
+			.ret = false,
+		};
+
+		drm_for_each_detailed_block((u8 *)edid, is_rb, &closure);
+
+		return closure.ret;
 	}
 
 	return ((edid->input & DRM_EDID_INPUT_DIGITAL) != 0);
 }
 
+struct data_closure {
+	const u8 *data;
+};
+
 static void
-find_gtf2(struct detailed_timing *t, void *data)
+do_find_gtf2(const struct detailed_timing *t, void *c)
 {
-	u8 *r = (u8 *)t;
+	struct data_closure *closure = c;
+	const u8 *r = (const u8 *)t;
 
 	if (!is_display_descriptor(r, EDID_DETAIL_MONITOR_RANGE))
 		return;
 
 	if (r[10] == 0x02)
-		*(u8 **)data = r;
+		closure->data = r;
+}
+
+static const u8 *
+find_gtf2_descriptor(const struct edid *edid)
+{
+	struct data_closure closure = {};
+
+	drm_for_each_detailed_block((u8 *)edid, do_find_gtf2, &closure);
+
+	return closure.data;
 }
 
 /* Secondary GTF curve kicks in above some break frequency */
 static int
-drm_gtf2_hbreak(struct edid *edid)
+drm_gtf2_hbreak(const struct edid *edid)
 {
-	u8 *r = NULL;
-	drm_for_each_detailed_block((u8 *)edid, find_gtf2, &r);
-	return r ? (r[12] * 2) : 0;
+	const u8 *r = find_gtf2_descriptor(edid);
+
+	return r ? r[12] * 2 : 0;
 }
 
 static int
-drm_gtf2_2c(struct edid *edid)
+drm_gtf2_2c(const struct edid *edid)
 {
-	u8 *r = NULL;
-	drm_for_each_detailed_block((u8 *)edid, find_gtf2, &r);
+	const u8 *r = find_gtf2_descriptor(edid);
+
 	return r ? r[13] : 0;
 }
 
 static int
-drm_gtf2_m(struct edid *edid)
+drm_gtf2_m(const struct edid *edid)
 {
-	u8 *r = NULL;
-	drm_for_each_detailed_block((u8 *)edid, find_gtf2, &r);
-	return r ? (r[15] << 8) + r[14] : 0;
+	const u8 *r = find_gtf2_descriptor(edid);
+
+	return r ? (r[15] << 8) | r[14] : 0;
 }
 
 static int
-drm_gtf2_k(struct edid *edid)
+drm_gtf2_k(const struct edid *edid)
 {
-	u8 *r = NULL;
-	drm_for_each_detailed_block((u8 *)edid, find_gtf2, &r);
+	const u8 *r = find_gtf2_descriptor(edid);
+
 	return r ? r[16] : 0;
 }
 
 static int
-drm_gtf2_2j(struct edid *edid)
+drm_gtf2_2j(const struct edid *edid)
 {
-	u8 *r = NULL;
-	drm_for_each_detailed_block((u8 *)edid, find_gtf2, &r);
+	const u8 *r = find_gtf2_descriptor(edid);
+
 	return r ? r[17] : 0;
 }
 
@@ -2346,7 +2370,7 @@ drm_gtf2_2j(struct edid *edid)
  * standard_timing_level - get std. timing level(CVT/GTF/DMT)
  * @edid: EDID block to scan
  */
-static int standard_timing_level(struct edid *edid)
+static int standard_timing_level(const struct edid *edid)
 {
 	if (edid->revision >= 2) {
 		if (edid->revision >= 4 && (edid->features & DRM_EDID_FEATURE_DEFAULT_GTF))
@@ -2381,8 +2405,9 @@ bad_std_timing(u8 a, u8 b)
  * and convert them into a real mode using CVT/GTF/DMT.
  */
 static struct drm_display_mode *
-drm_mode_std(struct drm_connector *connector, struct edid *edid,
-	     struct std_timing *t)
+drm_mode_std(struct drm_connector *connector,
+	     const struct edid *edid,
+	     const struct std_timing *t)
 {
 	struct drm_device *dev = connector->dev;
 	struct drm_display_mode *m, *mode = NULL;
@@ -2500,7 +2525,7 @@ drm_mode_std(struct drm_connector *connector, struct edid *edid,
  */
 static void
 drm_mode_do_interlace_quirk(struct drm_display_mode *mode,
-			    struct detailed_pixel_timing *pt)
+			    const struct detailed_pixel_timing *pt)
 {
 	int i;
 	static const struct {
@@ -2543,12 +2568,12 @@ drm_mode_do_interlace_quirk(struct drm_display_mode *mode,
  * return a new struct drm_display_mode.
  */
 static struct drm_display_mode *drm_mode_detailed(struct drm_device *dev,
-						  struct edid *edid,
-						  struct detailed_timing *timing,
+						  const struct edid *edid,
+						  const struct detailed_timing *timing,
 						  u32 quirks)
 {
 	struct drm_display_mode *mode;
-	struct detailed_pixel_timing *pt = &timing->data.pixel_data;
+	const struct detailed_pixel_timing *pt = &timing->data.pixel_data;
 	unsigned hactive = (pt->hactive_hblank_hi & 0xf0) << 4 | pt->hactive_lo;
 	unsigned vactive = (pt->vactive_vblank_hi & 0xf0) << 4 | pt->vactive_lo;
 	unsigned hblank = (pt->hactive_hblank_hi & 0xf) << 8 | pt->hblank_lo;
@@ -2590,9 +2615,9 @@ static struct drm_display_mode *drm_mode_detailed(struct drm_device *dev,
 		return NULL;
 
 	if (quirks & EDID_QUIRK_135_CLOCK_TOO_HIGH)
-		timing->pixel_clock = cpu_to_le16(1088);
-
-	mode->clock = le16_to_cpu(timing->pixel_clock) * 10;
+		mode->clock = 1088 * 10;
+	else
+		mode->clock = le16_to_cpu(timing->pixel_clock) * 10;
 
 	mode->hdisplay = hactive;
 	mode->hsync_start = mode->hdisplay + hsync_offset;
@@ -2613,14 +2638,14 @@ static struct drm_display_mode *drm_mode_detailed(struct drm_device *dev,
 	drm_mode_do_interlace_quirk(mode, pt);
 
 	if (quirks & EDID_QUIRK_DETAILED_SYNC_PP) {
-		pt->misc |= DRM_EDID_PT_HSYNC_POSITIVE | DRM_EDID_PT_VSYNC_POSITIVE;
+		mode->flags |= DRM_MODE_FLAG_PHSYNC | DRM_MODE_FLAG_NVSYNC;
+	} else {
+		mode->flags |= (pt->misc & DRM_EDID_PT_HSYNC_POSITIVE) ?
+			DRM_MODE_FLAG_PHSYNC : DRM_MODE_FLAG_NHSYNC;
+		mode->flags |= (pt->misc & DRM_EDID_PT_VSYNC_POSITIVE) ?
+			DRM_MODE_FLAG_PVSYNC : DRM_MODE_FLAG_NVSYNC;
 	}
 
-	mode->flags |= (pt->misc & DRM_EDID_PT_HSYNC_POSITIVE) ?
-		DRM_MODE_FLAG_PHSYNC : DRM_MODE_FLAG_NHSYNC;
-	mode->flags |= (pt->misc & DRM_EDID_PT_VSYNC_POSITIVE) ?
-		DRM_MODE_FLAG_PVSYNC : DRM_MODE_FLAG_NVSYNC;
-
 set_size:
 	mode->width_mm = pt->width_mm_lo | (pt->width_height_mm_hi & 0xf0) << 4;
 	mode->height_mm = pt->height_mm_lo | (pt->width_height_mm_hi & 0xf) << 8;
@@ -2644,7 +2669,7 @@ static struct drm_display_mode *drm_mode_detailed(struct drm_device *dev,
 
 static bool
 mode_in_hsync_range(const struct drm_display_mode *mode,
-		    struct edid *edid, u8 *t)
+		    const struct edid *edid, const u8 *t)
 {
 	int hsync, hmin, hmax;
 
@@ -2661,7 +2686,7 @@ mode_in_hsync_range(const struct drm_display_mode *mode,
 
 static bool
 mode_in_vsync_range(const struct drm_display_mode *mode,
-		    struct edid *edid, u8 *t)
+		    const struct edid *edid, const u8 *t)
 {
 	int vsync, vmin, vmax;
 
@@ -2677,7 +2702,7 @@ mode_in_vsync_range(const struct drm_display_mode *mode,
 }
 
 static u32
-range_pixel_clock(struct edid *edid, u8 *t)
+range_pixel_clock(const struct edid *edid, const u8 *t)
 {
 	/* unspecified */
 	if (t[9] == 0 || t[9] == 255)
@@ -2692,11 +2717,12 @@ range_pixel_clock(struct edid *edid, u8 *t)
 }
 
 static bool
-mode_in_range(const struct drm_display_mode *mode, struct edid *edid,
-	      struct detailed_timing *timing)
+mode_in_range(const struct drm_display_mode *mode,
+	      const struct edid *edid,
+	      const struct detailed_timing *timing)
 {
 	u32 max_clock;
-	u8 *t = (u8 *)timing;
+	const u8 *t = (const u8 *)timing;
 
 	if (!mode_in_hsync_range(mode, edid, t))
 		return false;
@@ -2738,8 +2764,9 @@ static bool valid_inferred_mode(const struct drm_connector *connector,
 }
 
 static int
-drm_dmt_modes_for_range(struct drm_connector *connector, struct edid *edid,
-			struct detailed_timing *timing)
+drm_dmt_modes_for_range(struct drm_connector *connector,
+			const struct edid *edid,
+			const struct detailed_timing *timing)
 {
 	int i, modes = 0;
 	struct drm_display_mode *newmode;
@@ -2773,8 +2800,9 @@ void drm_mode_fixup_1366x768(struct drm_display_mode *mode)
 }
 
 static int
-drm_gtf_modes_for_range(struct drm_connector *connector, struct edid *edid,
-			struct detailed_timing *timing)
+drm_gtf_modes_for_range(struct drm_connector *connector,
+			const struct edid *edid,
+			const struct detailed_timing *timing)
 {
 	int i, modes = 0;
 	struct drm_display_mode *newmode;
@@ -2801,8 +2829,9 @@ drm_gtf_modes_for_range(struct drm_connector *connector, struct edid *edid,
 }
 
 static int
-drm_cvt_modes_for_range(struct drm_connector *connector, struct edid *edid,
-			struct detailed_timing *timing)
+drm_cvt_modes_for_range(struct drm_connector *connector,
+			const struct edid *edid,
+			const struct detailed_timing *timing)
 {
 	int i, modes = 0;
 	struct drm_display_mode *newmode;
@@ -2830,11 +2859,11 @@ drm_cvt_modes_for_range(struct drm_connector *connector, struct edid *edid,
 }
 
 static void
-do_inferred_modes(struct detailed_timing *timing, void *c)
+do_inferred_modes(const struct detailed_timing *timing, void *c)
 {
 	struct detailed_mode_closure *closure = c;
-	struct detailed_non_pixel *data = &timing->data.other_data;
-	struct detailed_data_monitor_range *range = &data->data.range;
+	const struct detailed_non_pixel *data = &timing->data.other_data;
+	const struct detailed_data_monitor_range *range = &data->data.range;
 
 	if (!is_display_descriptor((const u8 *)timing, EDID_DETAIL_MONITOR_RANGE))
 		return;
@@ -2868,7 +2897,8 @@ do_inferred_modes(struct detailed_timing *timing, void *c)
 }
 
 static int
-add_inferred_modes(struct drm_connector *connector, struct edid *edid)
+add_inferred_modes(struct drm_connector *connector,
+		   const struct edid *edid)
 {
 	struct detailed_mode_closure closure = {
 		.connector = connector,
@@ -2876,18 +2906,20 @@ add_inferred_modes(struct drm_connector *connector, struct edid *edid)
 	};
 
 	if (version_greater(edid, 1, 0))
-		drm_for_each_detailed_block((u8 *)edid, do_inferred_modes,
+		drm_for_each_detailed_block((const u8 *)edid,
+					    do_inferred_modes,
 					    &closure);
 
 	return closure.modes;
 }
 
 static int
-drm_est3_modes(struct drm_connector *connector, struct detailed_timing *timing)
+drm_est3_modes(struct drm_connector *connector,
+	       const struct detailed_timing *timing)
 {
 	int i, j, m, modes = 0;
 	struct drm_display_mode *mode;
-	u8 *est = ((u8 *)timing) + 6;
+	const u8 *est = ((const u8 *)timing) + 6;
 
 	for (i = 0; i < 6; i++) {
 		for (j = 7; j >= 0; j--) {
@@ -2912,7 +2944,7 @@ drm_est3_modes(struct drm_connector *connector, struct detailed_timing *timing)
 }
 
 static void
-do_established_modes(struct detailed_timing *timing, void *c)
+do_established_modes(const struct detailed_timing *timing, void *c)
 {
 	struct detailed_mode_closure *closure = c;
 
@@ -2931,7 +2963,8 @@ do_established_modes(struct detailed_timing *timing, void *c)
  * (defined above).  Tease them out and add them to the global modes list.
  */
 static int
-add_established_modes(struct drm_connector *connector, struct edid *edid)
+add_established_modes(struct drm_connector *connector,
+		      const struct edid *edid)
 {
 	struct drm_device *dev = connector->dev;
 	unsigned long est_bits = edid->established_timings.t1 |
@@ -2962,19 +2995,19 @@ add_established_modes(struct drm_connector *connector, struct edid *edid)
 }
 
 static void
-do_standard_modes(struct detailed_timing *timing, void *c)
+do_standard_modes(const struct detailed_timing *timing, void *c)
 {
 	struct detailed_mode_closure *closure = c;
-	struct detailed_non_pixel *data = &timing->data.other_data;
+	const struct detailed_non_pixel *data = &timing->data.other_data;
 	struct drm_connector *connector = closure->connector;
-	struct edid *edid = closure->edid;
+	const struct edid *edid = closure->edid;
 	int i;
 
 	if (!is_display_descriptor((const u8 *)timing, EDID_DETAIL_STD_MODES))
 		return;
 
 	for (i = 0; i < 6; i++) {
-		struct std_timing *std = &data->data.timings[i];
+		const struct std_timing *std = &data->data.timings[i];
 		struct drm_display_mode *newmode;
 
 		newmode = drm_mode_std(connector, edid, std);
@@ -2994,7 +3027,8 @@ do_standard_modes(struct detailed_timing *timing, void *c)
  * GTF or CVT. Grab them from @edid and add them to the list.
  */
 static int
-add_standard_modes(struct drm_connector *connector, struct edid *edid)
+add_standard_modes(struct drm_connector *connector,
+		   const struct edid *edid)
 {
 	int i, modes = 0;
 	struct detailed_mode_closure closure = {
@@ -3023,18 +3057,18 @@ add_standard_modes(struct drm_connector *connector, struct edid *edid)
 }
 
 static int drm_cvt_modes(struct drm_connector *connector,
-			 struct detailed_timing *timing)
+			 const struct detailed_timing *timing)
 {
 	int i, j, modes = 0;
 	struct drm_display_mode *newmode;
 	struct drm_device *dev = connector->dev;
-	struct cvt_timing *cvt;
 	const int rates[] = { 60, 85, 75, 60, 50 };
 	const u8 empty[3] = { 0, 0, 0 };
 
 	for (i = 0; i < 4; i++) {
 		int uninitialized_var(width), height;
-		cvt = &(timing->data.other_data.data.cvt[i]);
+		const struct cvt_timing *cvt =
+			&timing->data.other_data.data.cvt[i];
 
 		if (!memcmp(cvt->code, empty, 3))
 			continue;
@@ -3072,7 +3106,7 @@ static int drm_cvt_modes(struct drm_connector *connector,
 }
 
 static void
-do_cvt_mode(struct detailed_timing *timing, void *c)
+do_cvt_mode(const struct detailed_timing *timing, void *c)
 {
 	struct detailed_mode_closure *closure = c;
 
@@ -3083,7 +3117,8 @@ do_cvt_mode(struct detailed_timing *timing, void *c)
 }
 
 static int
-add_cvt_modes(struct drm_connector *connector, struct edid *edid)
+add_cvt_modes(struct drm_connector *connector,
+	      const struct edid *edid)
 {
 	struct detailed_mode_closure closure = {
 		.connector = connector,
@@ -3101,7 +3136,7 @@ add_cvt_modes(struct drm_connector *connector, struct edid *edid)
 static void fixup_detailed_cea_mode_clock(struct drm_display_mode *mode);
 
 static void
-do_detailed_mode(struct detailed_timing *timing, void *c)
+do_detailed_mode(const struct detailed_timing *timing, void *c)
 {
 	struct detailed_mode_closure *closure = c;
 	struct drm_display_mode *newmode;
@@ -3137,8 +3172,8 @@ do_detailed_mode(struct detailed_timing *timing, void *c)
  * @quirks: quirks to apply
  */
 static int
-add_detailed_modes(struct drm_connector *connector, struct edid *edid,
-		   u32 quirks)
+add_detailed_modes(struct drm_connector *connector,
+		   struct edid *edid, u32 quirks)
 {
 	struct detailed_mode_closure closure = {
 		.connector = connector,
@@ -3173,9 +3208,10 @@ add_detailed_modes(struct drm_connector *connector, struct edid *edid,
 /*
  * Search EDID for CEA extension block.
  */
-static u8 *drm_find_edid_extension(const struct edid *edid, int ext_id)
+static const u8 *drm_find_edid_extension(const struct edid *edid,
+					 int ext_id)
 {
-	u8 *edid_ext = NULL;
+	const u8 *edid_ext = NULL;
 	int i;
 
 	/* No EDID or EDID extensions */
@@ -3184,7 +3220,7 @@ static u8 *drm_find_edid_extension(const struct edid *edid, int ext_id)
 
 	/* Find CEA extension */
 	for (i = 0; i < edid->extensions; i++) {
-		edid_ext = (u8 *)edid + EDID_LENGTH * (i + 1);
+		edid_ext = (const u8 *)edid + EDID_LENGTH * (i + 1);
 		if (edid_ext[0] == ext_id)
 			break;
 	}
@@ -3196,19 +3232,19 @@ static u8 *drm_find_edid_extension(const struct edid *edid, int ext_id)
 }
 
 
-static u8 *drm_find_displayid_extension(const struct edid *edid)
+static const u8 *drm_find_displayid_extension(const struct edid *edid)
 {
 	return drm_find_edid_extension(edid, DISPLAYID_EXT);
 }
 
-static u8 *drm_find_cea_extension(const struct edid *edid)
+static const u8 *drm_find_cea_extension(const struct edid *edid)
 {
 	int ret;
 	int idx = 1;
 	int length = EDID_LENGTH;
-	struct displayid_block *block;
-	u8 *cea;
-	u8 *displayid;
+	const struct displayid_block *block;
+	const u8 *cea;
+	const u8 *displayid;
 
 	/* Look for a top level CEA extension block */
 	cea = drm_find_edid_extension(edid, CEA_EXT);
@@ -4315,28 +4351,30 @@ drm_parse_hdmi_vsdb_audio(struct drm_connector *connector, const u8 *db)
 }
 
 static void
-monitor_name(struct detailed_timing *t, void *data)
+monitor_name(const struct detailed_timing *t, void *c)
 {
+	struct data_closure *closure = c;
+
 	if (!is_display_descriptor((const u8 *)t, EDID_DETAIL_MONITOR_NAME))
 		return;
 
-	*(u8 **)data = t->data.other_data.data.str.str;
+	closure->data = t->data.other_data.data.str.str;
 }
 
 static int get_monitor_name(struct edid *edid, char name[13])
 {
-	char *edid_name = NULL;
+	struct data_closure closure = {};
 	int mnl;
 
 	if (!edid || !name)
 		return 0;
 
-	drm_for_each_detailed_block((u8 *)edid, monitor_name, &edid_name);
-	for (mnl = 0; edid_name && mnl < 13; mnl++) {
-		if (edid_name[mnl] == 0x0a)
+	drm_for_each_detailed_block((const u8 *)edid, monitor_name, &closure);
+	for (mnl = 0; closure.data && mnl < 13; mnl++) {
+		if (closure.data[mnl] == 0x0a)
 			break;
 
-		name[mnl] = edid_name[mnl];
+		name[mnl] = closure.data[mnl];
 	}
 
 	return mnl;
@@ -4386,11 +4424,9 @@ static void clear_eld(struct drm_connector *connector)
 static void drm_edid_to_eld(struct drm_connector *connector, struct edid *edid)
 {
 	uint8_t *eld = connector->eld;
-	u8 *cea;
-	u8 *db;
+	const u8 *cea;
 	int total_sad_count = 0;
 	int mnl;
-	int dbl;
 
 	clear_eld(connector);
 
@@ -4425,8 +4461,8 @@ static void drm_edid_to_eld(struct drm_connector *connector, struct edid *edid)
 		}
 
 		for_each_cea_db(cea, i, start, end) {
-			db = &cea[i];
-			dbl = cea_db_payload_len(db);
+			const u8 *db = &cea[i];
+			int dbl = cea_db_payload_len(db);
 
 			switch (cea_db_tag(db)) {
 				int sad_count;
@@ -4484,7 +4520,7 @@ int drm_edid_to_sad(struct edid *edid, struct cea_sad **sads)
 {
 	int count = 0;
 	int i, start, end, dbl;
-	u8 *cea;
+	const u8 *cea;
 
 	cea = drm_find_cea_extension(edid);
 	if (!cea) {
@@ -4503,7 +4539,7 @@ int drm_edid_to_sad(struct edid *edid, struct cea_sad **sads)
 	}
 
 	for_each_cea_db(cea, i, start, end) {
-		u8 *db = &cea[i];
+		const u8 *db = &cea[i];
 
 		if (cea_db_tag(db) == AUDIO_BLOCK) {
 			int j;
@@ -4514,7 +4550,7 @@ int drm_edid_to_sad(struct edid *edid, struct cea_sad **sads)
 			if (!*sads)
 				return -ENOMEM;
 			for (j = 0; j < count; j++) {
-				u8 *sad = &db[1 + j * 3];
+				const u8 *sad = &db[1 + j * 3];
 
 				(*sads)[j].format = (sad[0] & 0x78) >> 3;
 				(*sads)[j].channels = sad[0] & 0x7;
@@ -4635,7 +4671,7 @@ EXPORT_SYMBOL(drm_av_sync_delay);
  */
 bool drm_detect_hdmi_monitor(struct edid *edid)
 {
-	u8 *edid_ext;
+	const u8 *edid_ext;
 	int i;
 	int start_offset, end_offset;
 
@@ -4673,7 +4709,7 @@ EXPORT_SYMBOL(drm_detect_hdmi_monitor);
  */
 bool drm_detect_monitor_audio(struct edid *edid)
 {
-	u8 *edid_ext;
+	const u8 *edid_ext;
 	int i, j;
 	bool has_audio = false;
 	int start_offset, end_offset;
@@ -5017,13 +5053,13 @@ u32 drm_add_display_info(struct drm_connector *connector, const struct edid *edi
 	return quirks;
 }
 
-static int validate_displayid(u8 *displayid, int length, int idx)
+static int validate_displayid(const u8 *displayid, int length, int idx)
 {
 	int i;
 	u8 csum = 0;
-	struct displayid_hdr *base;
+	const struct displayid_hdr *base;
 
-	base = (struct displayid_hdr *)&displayid[idx];
+	base = (const struct displayid_hdr *)&displayid[idx];
 
 	DRM_DEBUG_KMS("base revision 0x%x, length %d, %d %d\n",
 		      base->rev, base->bytes, base->prod_id, base->ext_count);
@@ -5041,7 +5077,7 @@ static int validate_displayid(u8 *displayid, int length, int idx)
 }
 
 static struct drm_display_mode *drm_mode_displayid_detailed(struct drm_device *dev,
-							    struct displayid_detailed_timings_1 *timings)
+							    const struct displayid_detailed_timings_1 *timings)
 {
 	struct drm_display_mode *mode;
 	unsigned pixel_clock = (timings->pixel_clock[0] |
@@ -5057,6 +5093,7 @@ static struct drm_display_mode *drm_mode_displayid_detailed(struct drm_device *d
 	unsigned vsync_width = (timings->vsw[0] | timings->vsw[1] << 8) + 1;
 	bool hsync_positive = (timings->hsync[1] >> 7) & 0x1;
 	bool vsync_positive = (timings->vsync[1] >> 7) & 0x1;
+
 	mode = drm_mode_create(dev);
 	if (!mode)
 		return NULL;
@@ -5086,9 +5123,10 @@ static struct drm_display_mode *drm_mode_displayid_detailed(struct drm_device *d
 }
 
 static int add_displayid_detailed_1_modes(struct drm_connector *connector,
-					  struct displayid_block *block)
+					  const struct displayid_block *block)
 {
-	struct displayid_detailed_timing_block *det = (struct displayid_detailed_timing_block *)block;
+	const struct displayid_detailed_timing_block *det =
+		(const struct displayid_detailed_timing_block *)block;
 	int i;
 	int num_timings;
 	struct drm_display_mode *newmode;
@@ -5099,7 +5137,7 @@ static int add_displayid_detailed_1_modes(struct drm_connector *connector,
 
 	num_timings = block->num_bytes / 20;
 	for (i = 0; i < num_timings; i++) {
-		struct displayid_detailed_timings_1 *timings = &det->timings[i];
+		const struct displayid_detailed_timings_1 *timings = &det->timings[i];
 
 		newmode = drm_mode_displayid_detailed(connector->dev, timings);
 		if (!newmode)
@@ -5112,13 +5150,13 @@ static int add_displayid_detailed_1_modes(struct drm_connector *connector,
 }
 
 static int add_displayid_detailed_modes(struct drm_connector *connector,
-					struct edid *edid)
+					const struct edid *edid)
 {
-	u8 *displayid;
+	const u8 *displayid;
 	int ret;
 	int idx = 1;
 	int length = EDID_LENGTH;
-	struct displayid_block *block;
+	const struct displayid_block *block;
 	int num_modes = 0;
 
 	displayid = drm_find_displayid_extension(edid);
@@ -5720,9 +5758,10 @@ drm_hdmi_vendor_infoframe_from_display_mode(struct hdmi_vendor_infoframe *frame,
 EXPORT_SYMBOL(drm_hdmi_vendor_infoframe_from_display_mode);
 
 static int drm_parse_tiled_block(struct drm_connector *connector,
-				 struct displayid_block *block)
+				 const struct displayid_block *block)
 {
-	struct displayid_tiled_block *tile = (struct displayid_tiled_block *)block;
+	const struct displayid_tiled_block *tile =
+		(const struct displayid_tiled_block *)block;
 	u16 w, h;
 	u8 tile_v_loc, tile_h_loc;
 	u8 num_v_tile, num_h_tile;
@@ -5774,12 +5813,12 @@ static int drm_parse_tiled_block(struct drm_connector *connector,
 }
 
 static int drm_parse_display_id(struct drm_connector *connector,
-				u8 *displayid, int length,
+				const u8 *displayid, int length,
 				bool is_edid_extension)
 {
 	/* if this is an EDID extension the first byte will be 0x70 */
 	int idx = 0;
-	struct displayid_block *block;
+	const struct displayid_block *block;
 	int ret;
 
 	if (is_edid_extension)
@@ -5815,11 +5854,13 @@ static int drm_parse_display_id(struct drm_connector *connector,
 }
 
 static void drm_get_displayid(struct drm_connector *connector,
-			      struct edid *edid)
+			      const struct edid *edid)
 {
-	void *displayid = NULL;
+	const void *displayid;
 	int ret;
+
 	connector->has_tile = false;
+
 	displayid = drm_find_displayid_extension(edid);
 	if (!displayid) {
 		/* drop reference to any tile group we had */
diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
index 2113500b4075..c0f9ce3f4b24 100644
--- a/include/drm/drm_connector.h
+++ b/include/drm/drm_connector.h
@@ -1580,9 +1580,9 @@ struct drm_tile_group {
 };
 
 struct drm_tile_group *drm_mode_create_tile_group(struct drm_device *dev,
-						  char topology[8]);
+						  const u8 topology[8]);
 struct drm_tile_group *drm_mode_get_tile_group(struct drm_device *dev,
-					       char topology[8]);
+					       const u8 topology[8]);
 void drm_mode_put_tile_group(struct drm_device *dev,
 			     struct drm_tile_group *tg);
 
