Merge tag 'drm-misc-fixes-2025-03-13' of https://gitlab.freedesktop.org/drm/misc/kernel into drm-fixes

A null pointer check for gma500, two clippy fixes for panic, a fix for
an interaction between DPMS and atomic leading to dropped frames, and
a locking fix  for dp_mst

Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Maxime Ripard <mripard@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250313-holistic-clay-moose-fead28@houat

Author: airlied

drivers/gpu/drm/display/drm_dp_mst_topology.c

@@ -4025,6 +4025,22 @@ static int drm_dp_mst_handle_down_rep(struct drm_dp_mst_topology_mgr *mgr)
 	return 0;
 }
 
+static bool primary_mstb_probing_is_done(struct drm_dp_mst_topology_mgr *mgr)
+{
+	bool probing_done = false;
+
+	mutex_lock(&mgr->lock);
+
+	if (mgr->mst_primary && drm_dp_mst_topology_try_get_mstb(mgr->mst_primary)) {
+		probing_done = mgr->mst_primary->link_address_sent;
+		drm_dp_mst_topology_put_mstb(mgr->mst_primary);
+	}
+
+	mutex_unlock(&mgr->lock);
+
+	return probing_done;
+}
+
 static inline bool
 drm_dp_mst_process_up_req(struct drm_dp_mst_topology_mgr *mgr,
 			  struct drm_dp_pending_up_req *up_req)
@@ -4055,8 +4071,12 @@ drm_dp_mst_process_up_req(struct drm_dp_mst_topology_mgr *mgr,
 
 	/* TODO: Add missing handler for DP_RESOURCE_STATUS_NOTIFY events */
 	if (msg->req_type == DP_CONNECTION_STATUS_NOTIFY) {
-		dowork = drm_dp_mst_handle_conn_stat(mstb, &msg->u.conn_stat);
-		hotplug = true;
+		if (!primary_mstb_probing_is_done(mgr)) {
+			drm_dbg_kms(mgr->dev, "Got CSN before finish topology probing. Skip it.\n");
+		} else {
+			dowork = drm_dp_mst_handle_conn_stat(mstb, &msg->u.conn_stat);
+			hotplug = true;
+		}
 	}
 
 	drm_dp_mst_topology_put_mstb(mstb);
@@ -4138,10 +4158,11 @@ static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr)
 	drm_dp_send_up_ack_reply(mgr, mst_primary, up_req->msg.req_type,
 				 false);
 
+	drm_dp_mst_topology_put_mstb(mst_primary);
+
 	if (up_req->msg.req_type == DP_CONNECTION_STATUS_NOTIFY) {
 		const struct drm_dp_connection_status_notify *conn_stat =
 			&up_req->msg.u.conn_stat;
-		bool handle_csn;
 
 		drm_dbg_kms(mgr->dev, "Got CSN: pn: %d ldps:%d ddps: %d mcs: %d ip: %d pdt: %d\n",
 			    conn_stat->port_number,
@@ -4150,16 +4171,6 @@ static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr)
 			    conn_stat->message_capability_status,
 			    conn_stat->input_port,
 			    conn_stat->peer_device_type);
-
-		mutex_lock(&mgr->probe_lock);
-		handle_csn = mst_primary->link_address_sent;
-		mutex_unlock(&mgr->probe_lock);
-
-		if (!handle_csn) {
-			drm_dbg_kms(mgr->dev, "Got CSN before finish topology probing. Skip it.");
-			kfree(up_req);
-			goto out_put_primary;
-		}
 	} else if (up_req->msg.req_type == DP_RESOURCE_STATUS_NOTIFY) {
 		const struct drm_dp_resource_status_notify *res_stat =
 			&up_req->msg.u.resource_stat;
@@ -4174,9 +4185,6 @@ static int drm_dp_mst_handle_up_req(struct drm_dp_mst_topology_mgr *mgr)
 	list_add_tail(&up_req->next, &mgr->up_req_list);
 	mutex_unlock(&mgr->up_req_lock);
 	queue_work(system_long_wq, &mgr->up_req_work);
-
-out_put_primary:
-	drm_dp_mst_topology_put_mstb(mst_primary);
 out_clear_reply:
 	reset_msg_rx_state(&mgr->up_req_recv);
 	return ret;

drivers/gpu/drm/drm_atomic_uapi.c

@@ -956,6 +956,10 @@ int drm_atomic_connector_commit_dpms(struct drm_atomic_state *state,
 
 	if (mode != DRM_MODE_DPMS_ON)
 		mode = DRM_MODE_DPMS_OFF;
+
+	if (connector->dpms == mode)
+		goto out;
+
 	connector->dpms = mode;
 
 	crtc = connector->state->crtc;

drivers/gpu/drm/drm_connector.c

@@ -1427,6 +1427,10 @@ EXPORT_SYMBOL(drm_hdmi_connector_get_output_format_name);
  * 	callback. For atomic drivers the remapping to the "ACTIVE" property is
  * 	implemented in the DRM core.
  *
+ * 	On atomic drivers any DPMS setproperty ioctl where the value does not
+ * 	change is completely skipped, otherwise a full atomic commit will occur.
+ * 	On legacy drivers the exact behavior is driver specific.
+ *
  * 	Note that this property cannot be set through the MODE_ATOMIC ioctl,
  * 	userspace must use "ACTIVE" on the CRTC instead.
  *

drivers/gpu/drm/drm_panic_qr.rs

@@ -545,7 +545,7 @@ impl EncodedMsg<'_> {
         }
         self.push(&mut offset, (MODE_STOP, 4));
 
-        let pad_offset = (offset + 7) / 8;
+        let pad_offset = offset.div_ceil(8);
         for i in pad_offset..self.version.max_data() {
             self.data[i] = PADDING[(i & 1) ^ (pad_offset & 1)];
         }
@@ -659,7 +659,7 @@ struct QrImage<'a> {
 impl QrImage<'_> {
     fn new<'a, 'b>(em: &'b EncodedMsg<'b>, qrdata: &'a mut [u8]) -> QrImage<'a> {
         let width = em.version.width();
-        let stride = (width + 7) / 8;
+        let stride = width.div_ceil(8);
         let data = qrdata;
 
         let mut qr_image = QrImage {
@@ -911,16 +911,16 @@ impl QrImage<'_> {
 ///
 /// * `url`: The base URL of the QR code. It will be encoded as Binary segment.
 /// * `data`: A pointer to the binary data, to be encoded. if URL is NULL, it
-///    will be encoded as binary segment, otherwise it will be encoded
-///    efficiently as a numeric segment, and appended to the URL.
+///   will be encoded as binary segment, otherwise it will be encoded
+///   efficiently as a numeric segment, and appended to the URL.
 /// * `data_len`: Length of the data, that needs to be encoded, must be less
-///    than data_size.
+///   than data_size.
 /// * `data_size`: Size of data buffer, it should be at least 4071 bytes to hold
-///    a V40 QR code. It will then be overwritten with the QR code image.
+///   a V40 QR code. It will then be overwritten with the QR code image.
 /// * `tmp`: A temporary buffer that the QR code encoder will use, to write the
-///    segments and ECC.
+///   segments and ECC.
 /// * `tmp_size`: Size of the temporary buffer, it must be at least 3706 bytes
-///    long for V40.
+///   long for V40.
 ///
 /// # Safety
 ///

drivers/gpu/drm/gma500/mid_bios.c

@@ -279,6 +279,11 @@ static void mid_get_vbt_data(struct drm_psb_private *dev_priv)
 					    0, PCI_DEVFN(2, 0));
 	int ret = -1;
 
+	if (pci_gfx_root == NULL) {
+		WARN_ON(1);
+		return;
+	}
+
 	/* Get the address of the platform config vbt */
 	pci_read_config_dword(pci_gfx_root, 0xFC, &addr);
 	pci_dev_put(pci_gfx_root);