Downstream fixes for Unicam

drivers/media/platform/broadcom/bcm2835-unicam.c

@@ -550,7 +550,8 @@ unicam_find_format_by_fourcc(u32 fourcc, u32 pad)
 	}
 
 	for (i = 0; i < num_formats; ++i) {
-		if (formats[i].fourcc == fourcc)
+		if (formats[i].fourcc == fourcc ||
+		    formats[i].unpacked_fourcc == fourcc)
 			return &formats[i];
 	}
 
@@ -640,9 +641,9 @@ static inline void unicam_reg_write_field(struct unicam_device *unicam, u32 offs
 }
 
 static void unicam_wr_dma_addr(struct unicam_node *node,
-			       struct unicam_buffer *buf)
+			       struct unicam_buffer *buf, unsigned int size)
 {
-	dma_addr_t endaddr = buf->dma_addr + buf->size;
+	dma_addr_t endaddr = buf->dma_addr + size;
 
 	if (node->id == UNICAM_IMAGE_NODE) {
 		unicam_reg_write(node->dev, UNICAM_IBSA0, buf->dma_addr);
@@ -675,16 +676,21 @@ static void unicam_schedule_next_buffer(struct unicam_node *node)
 	node->next_frm = buf;
 	list_del(&buf->list);
 
-	unicam_wr_dma_addr(node, buf);
+	unicam_wr_dma_addr(node, buf, buf->size);
 }
 
 static void unicam_schedule_dummy_buffer(struct unicam_node *node)
 {
 	int node_id = is_image_node(node) ? UNICAM_IMAGE_NODE : UNICAM_METADATA_NODE;
 
 	dev_dbg(node->dev->dev, "Scheduling dummy buffer for node %d\n", node_id);
-
-	unicam_wr_dma_addr(node, &node->dummy_buf);
+	/*
+	 * Due to a HW bug causing buffer overruns in circular buffer mode under
+	 * certain (not yet fully known) conditions, the dummy buffer allocation
+	 * is set to a a single page size, but the hardware gets programmed with
+	 * a buffer size of 0.
+	 */
+	unicam_wr_dma_addr(node, &node->dummy_buf, 0);
 
 	node->next_frm = NULL;
 }
@@ -771,10 +777,25 @@ static irqreturn_t unicam_isr(int irq, void *dev)
 			 * as complete, as the HW will reuse that buffer.
 			 */
 			if (node->cur_frm && node->cur_frm != node->next_frm) {
+				/*
+				 * This condition checks if FE + FS for the same
+				 * frame has occurred. In such cases, we cannot
+				 * return out the frame, as no buffer handling
+				 * or timestamping has yet been done as part of
+				 * the FS handler.
+				 */
+				if (!node->cur_frm->vb.vb2_buf.timestamp) {
+					dev_dbg(unicam->dev, "ISR: FE without FS, dropping frame\n");
+					continue;
+				}
+
 				unicam_process_buffer_complete(node, sequence);
+				node->cur_frm = node->next_frm;
+				node->next_frm = NULL;
 				inc_seq = true;
+			} else {
+				node->cur_frm = node->next_frm;
 			}
-			node->cur_frm = node->next_frm;
 		}
 
 		/*
@@ -807,17 +828,32 @@ static irqreturn_t unicam_isr(int irq, void *dev)
 				continue;
 
 			if (node->cur_frm)
-				node->cur_frm->vb.vb2_buf.timestamp = ts;
+				node->cur_frm->vb.vb2_buf.timestamp =
+								ts;
 			else
-				dev_dbg(unicam->v4l2_dev.dev,
-					"ISR: [%d] Dropping frame, buffer not available at FS\n",
+				dev_dbg(unicam->dev, "ISR: [%d] Dropping frame, buffer not available at FS\n",
 					i);
 			/*
 			 * Set the next frame output to go to a dummy frame
-			 * if we have not managed to obtain another frame
-			 * from the queue.
+			 * if no buffer currently queued.
 			 */
-			unicam_schedule_dummy_buffer(node);
+			if (!node->next_frm ||
+			    node->next_frm == node->cur_frm) {
+				unicam_schedule_dummy_buffer(node);
+			} else if (unicam->node[i].cur_frm) {
+				/*
+				 * Repeated FS without FE. Hardware will have
+				 * swapped buffers, but the cur_frm doesn't
+				 * contain valid data. Return cur_frm to the
+				 * queue.
+				 */
+				spin_lock(&node->dma_queue_lock);
+				list_add_tail(&node->cur_frm->list,
+					      &node->dma_queue);
+				spin_unlock(&node->dma_queue_lock);
+				node->cur_frm = node->next_frm;
+				node->next_frm = NULL;
+			}
 		}
 
 		unicam_queue_event_sof(unicam);
@@ -843,11 +879,6 @@ static irqreturn_t unicam_isr(int irq, void *dev)
 		}
 	}
 
-	if (unicam_reg_read(unicam, UNICAM_ICTL) & UNICAM_FCM) {
-		/* Switch out of trigger mode if selected */
-		unicam_reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_TFC);
-		unicam_reg_write_field(unicam, UNICAM_ICTL, 0, UNICAM_FCM);
-	}
 	return IRQ_HANDLED;
 }
 
@@ -1011,8 +1042,7 @@ static void unicam_start_rx(struct unicam_device *unicam,
 
 	unicam_reg_write_field(unicam, UNICAM_ANA, 0, UNICAM_DDL);
 
-	/* Always start in trigger frame capture mode (UNICAM_FCM set) */
-	val = UNICAM_FSIE | UNICAM_FEIE | UNICAM_FCM | UNICAM_IBOB;
+	val = UNICAM_FSIE | UNICAM_FEIE | UNICAM_IBOB;
 	line_int_freq = max(fmt->height >> 2, 128);
 	unicam_set_field(&val, line_int_freq, UNICAM_LCIE_MASK);
 	unicam_reg_write(unicam, UNICAM_ICTL, val);
@@ -1101,7 +1131,7 @@ static void unicam_start_rx(struct unicam_device *unicam,
 
 	unicam_reg_write(unicam, UNICAM_IBLS,
 			 node->fmt.fmt.pix.bytesperline);
-	unicam_wr_dma_addr(node, node->cur_frm);
+	unicam_wr_dma_addr(node, node->cur_frm, node->cur_frm->size);
 	unicam_set_packing_config(unicam, fmtinfo);
 
 	ret = unicam_get_image_vc_dt(unicam, state, &vc, &dt);
@@ -1139,7 +1169,7 @@ static void unicam_start_metadata(struct unicam_device *unicam)
 	struct unicam_node *node = &unicam->node[UNICAM_METADATA_NODE];
 
 	unicam_enable_ed(unicam);
-	unicam_wr_dma_addr(node, node->cur_frm);
+	unicam_wr_dma_addr(node, node->cur_frm, node->cur_frm->size);
 	unicam_reg_write_field(unicam, UNICAM_DCS, 1, UNICAM_LDP);
 }