Re: [PATCH v7 2/5] media: platform: visconti: Add Toshiba Visconti Video Input Interface driver

On 14/07/2023 03:50, Yuji Ishikawa wrote:

Add support to Video Input Interface on Toshiba Visconti ARM SoCs.
The interface device includes CSI2 Receiver,
frame grabber, video DMAC and image signal processor.

A driver instance provides three /dev/videoX device files;
one for RGB image capture, another one for optional RGB capture
with different parameters and the last one for RAW capture.

...

+static int visconti_viif_parse_dt(struct viif_device *viif_dev)
+{
+	struct device_node *of = viif_dev->dev->of_node;
+	struct v4l2_fwnode_endpoint fw_ep;
+	struct viif_subdev *viif_sd;
+	struct device_node *ep;
+	unsigned int i;
+	int num_ep;
+	int ret;
+
+	memset(&fw_ep, 0, sizeof(struct v4l2_fwnode_endpoint));

Why you cannot initialize it in declaration? = { 0 }?

+
+	num_ep = of_graph_get_endpoint_count(of);
+	if (!num_ep)
+		return -ENODEV;
+
+	ret = visconti_viif_init_async_subdevs(viif_dev, num_ep);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < num_ep; i++) {
+		ep = of_graph_get_endpoint_by_regs(of, 0, i);
+		if (!ep) {
+			dev_err(viif_dev->dev, "No subdevice connected on endpoint %u.\n", i);
+			ret = -ENODEV;
+			goto error_put_node;
+		}
+
+		ret = v4l2_fwnode_endpoint_parse(of_fwnode_handle(ep), &fw_ep);
+		if (ret) {
+			dev_err(viif_dev->dev, "Unable to parse endpoint #%u.\n", i);
+			goto error_put_node;
+		}
+
+		if (fw_ep.bus_type != V4L2_MBUS_CSI2_DPHY ||
+		    fw_ep.bus.mipi_csi2.num_data_lanes == 0) {
+			dev_err(viif_dev->dev, "missing CSI-2 properties in endpoint\n");
+			ret = -EINVAL;
+			goto error_put_node;
+		}
+
+		/* Setup the ceu subdevice and the async subdevice. */
+		viif_sd = &viif_dev->subdevs[i];
+		INIT_LIST_HEAD(&viif_sd->asd.list);
+
+		viif_sd->num_lane = fw_ep.bus.mipi_csi2.num_data_lanes;
+		viif_sd->asd.match_type = V4L2_ASYNC_MATCH_FWNODE;
+		viif_sd->asd.match.fwnode =
+			fwnode_graph_get_remote_port_parent(of_fwnode_handle(ep));
+
+		viif_dev->asds[i] = &viif_sd->asd;
+		of_node_put(ep);
+	}
+
+	return num_ep;
+
+error_put_node:
+	of_node_put(ep);
+	return ret;
+}
+
+static const struct of_device_id visconti_viif_of_table[] = {
+	{
+		.compatible = "toshiba,visconti5-viif",
+	},
+	{},
+};
+MODULE_DEVICE_TABLE(of, visconti_viif_of_table);
+
+#define NUM_IRQS   3
+#define IRQ_ID_STR "viif"
+
+static int visconti_viif_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct viif_device *viif_dev;
+	dma_addr_t tables_dma;
+	int ret, i, num_sd;
+
+	ret = dma_set_mask_and_coherent(dev, DMA_BIT_MASK(36));
+	if (ret)
+		return ret;
+
+	viif_dev = devm_kzalloc(dev, sizeof(*viif_dev), GFP_KERNEL);
+	if (!viif_dev)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, viif_dev);
+	viif_dev->dev = dev;
+
+	spin_lock_init(&viif_dev->regbuf_lock);
+	mutex_init(&viif_dev->pow_lock);
+	mutex_init(&viif_dev->stream_lock);
+
+	viif_dev->capture_reg = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(viif_dev->capture_reg))
+		return PTR_ERR(viif_dev->capture_reg);
+
+	viif_dev->csi2host_reg = devm_platform_ioremap_resource(pdev, 1);
+	if (IS_ERR(viif_dev->csi2host_reg))
+		return PTR_ERR(viif_dev->csi2host_reg);
+
+	viif_dev->hwaif_reg = devm_platform_ioremap_resource(pdev, 2);
+	if (IS_ERR(viif_dev->hwaif_reg))
+		return PTR_ERR(viif_dev->hwaif_reg);
+
+	viif_dev->mpu_reg = devm_platform_ioremap_resource(pdev, 3);
+	if (IS_ERR(viif_dev->mpu_reg))
+		return PTR_ERR(viif_dev->mpu_reg);
+
+	viif_dev->run_flag_main = false;
+
+	for (i = 0; i < NUM_IRQS; i++) {
+		ret = platform_get_irq(pdev, i);
+		if (ret < 0) {
+			dev_err(dev, "failed to acquire irq resource\n");
+			return ret;

return dev_err_probe()

+		}
+		viif_dev->irq[i] = ret;
+		ret = devm_request_irq(dev, viif_dev->irq[i], visconti_viif_irq, 0, IRQ_ID_STR,
+				       viif_dev);
+		if (ret) {
+			dev_err(dev, "irq request failed\n");

return dev_err_probe()

+			return ret;
+		}
+	}
+
+	viif_dev->tables =
+		dma_alloc_wc(dev, sizeof(struct viif_table_area), &tables_dma, GFP_KERNEL);
+	if (!viif_dev->tables) {
+		dev_err(dev, "dma_alloc_wc failed\n");

Are you sure DMA memory allocation errors shall be printed?

+		return -ENOMEM;
+	}
+	viif_dev->tables_dma = (struct viif_table_area *)tables_dma;
+
+	/* power control */

Drop the comment, it is useless.

+	pm_runtime_enable(dev);
+
+	/* build media_dev */
+	viif_dev->media_dev.hw_revision = 0;
+	strscpy(viif_dev->media_dev.model, VIIF_DRIVER_NAME, sizeof(viif_dev->media_dev.model));
+	viif_dev->media_dev.dev = dev;
+	/* TODO: platform:visconti-viif-0,1,2,3 for each VIIF driver instance */
+	snprintf(viif_dev->media_dev.bus_info, sizeof(viif_dev->media_dev.bus_info), "%s-0",
+		 VIIF_BUS_INFO_BASE);
+	media_device_init(&viif_dev->media_dev);
+
+	/* build v4l2_dev */
+	viif_dev->v4l2_dev.mdev = &viif_dev->media_dev;
+	ret = v4l2_device_register(dev, &viif_dev->v4l2_dev);
+	if (ret)
+		goto error_dma_free;
+
+	ret = media_device_register(&viif_dev->media_dev);
+	if (ret) {
+		dev_err(dev, "Failed to register media device: %d\n", ret);
+		goto error_v4l2_unregister;

dev_err_probe

+	}
+
+	ret = visconti_viif_csi2rx_register(viif_dev);
+	if (ret) {
+		dev_err(dev, "failed to register csi2rx sub node: %d\n", ret);

dev_err_probe

+		goto error_media_unregister;
+	}
+
+	ret = visconti_viif_isp_register(viif_dev);
+	if (ret) {
+		dev_err(dev, "failed to register isp sub node: %d\n", ret);

dev_err_probe

+		goto error_media_unregister;
+	}
+	ret = visconti_viif_capture_register(viif_dev);
+	if (ret) {
+		dev_err(dev, "failed to register capture node: %d\n", ret);

dev_err_probe

+		goto error_media_unregister;
+	}
+
+	/* handle subdevices in device tree */
+	num_sd = visconti_viif_parse_dt(viif_dev);
+	if (ret < 0) {
+		ret = num_sd;

ret = dev_err_probe

+		goto error_media_unregister;
+	}
+
+	viif_dev->notifier.v4l2_dev = &viif_dev->v4l2_dev;
+	v4l2_async_nf_init(&viif_dev->notifier);
+	for (i = 0; i < num_sd; i++)
+		__v4l2_async_nf_add_subdev(&viif_dev->notifier, viif_dev->asds[i]);
+	viif_dev->notifier.ops = &viif_notify_ops;
+	ret = v4l2_async_nf_register(&viif_dev->v4l2_dev, &viif_dev->notifier);
+	if (ret)
+		goto error_media_unregister;
+
+	viif_dev->wq = create_workqueue("visconti-viif");
+	if (!viif_dev->wq)
+		return -ENOMEM;

No error cleanup?

+	INIT_WORK(&viif_dev->work, visconti_viif_wthread_l1info);
+
+	return 0;
+
+error_media_unregister:
+	media_device_unregister(&viif_dev->media_dev);
+error_v4l2_unregister:
+	v4l2_device_unregister(&viif_dev->v4l2_dev);
+error_dma_free:
+	pm_runtime_disable(dev);
+	dma_free_wc(&pdev->dev, sizeof(struct viif_table_area), viif_dev->tables,
+		    (dma_addr_t)viif_dev->tables_dma);
+	return ret;
+}
+
+static int visconti_viif_remove(struct platform_device *pdev)
+{
+	struct viif_device *viif_dev = platform_get_drvdata(pdev);
+
+	destroy_workqueue(viif_dev->wq);
+	visconti_viif_isp_unregister(viif_dev);
+	visconti_viif_capture_unregister(viif_dev);
+	v4l2_async_nf_unregister(&viif_dev->notifier);

Why these three are not called in probe error paths?

+	media_device_unregister(&viif_dev->media_dev);
+	v4l2_device_unregister(&viif_dev->v4l2_dev);
+	pm_runtime_disable(&pdev->dev);
+	dma_free_wc(&pdev->dev, sizeof(struct viif_table_area), viif_dev->tables,
+		    (dma_addr_t)viif_dev->tables_dma);
+
+	return 0;
+}
+
+static int visconti_viif_runtime_suspend(struct device *dev)
+{
+	/* This callback is kicked when the last device-file is closed */
+	struct viif_device *viif_dev = dev_get_drvdata(dev);
+
+	mutex_lock(&viif_dev->pow_lock);

Why?

+	visconti_viif_hw_off(viif_dev);
+	mutex_unlock(&viif_dev->pow_lock);
+
+	return 0;
+}
+
+static int visconti_viif_runtime_resume(struct device *dev)
+{
+	/* This callback is kicked when the first device-file is opened */
+	struct viif_device *viif_dev = dev_get_drvdata(dev);
+
+	viif_dev->rawpack_mode = (u32)VIIF_RAWPACK_DISABLE;
+
+	mutex_lock(&viif_dev->pow_lock);

Why?

+
+	/* Initialize HWD driver */
+	visconti_viif_hw_on(viif_dev);
+
+	/* VSYNC mask setting of MAIN unit */
+	viif_main_vsync_set_irq_mask(viif_dev, MASK_INT_M_SYNC_MASK_SET);
+
+	/* STATUS error mask setting of MAIN unit */
+	viif_main_status_err_set_irq_mask(viif_dev, MASK_INT_M_DELAY_INT_ERROR);
+
+	/* VSYNC mask settings of SUB unit */
+	viif_sub_vsync_set_irq_mask(viif_dev, MASK_INT_S_SYNC_MASK_SET);
+
+	/* STATUS error mask setting(unmask) of SUB unit */
+	viif_sub_status_err_set_irq_mask(viif_dev,
+					 MASK_INT_S_RESERVED_SET | MASK_INT_S_DELAY_INT_ERROR);
+
+	mutex_unlock(&viif_dev->pow_lock);
+
+	return 0;
+}
+

Best regards,
Krzysztof