[PATCH 03/12] usb: dwc3: qcom: Merge resources from urs_usb device

[Bjorn Andersson <quic_bjorande@quicinc.com>]

With some ACPI DSDT tables, such as the one found in SC8180X devices,
the USB resources are split between the URSn and it's child USBn device
nodes, in particular the interrupts are placed in the child nodes.

The solution that was chosen for handling this is to allocate a
platform_device from the child node and selectively pick interrupts
from the main platform_device, or from this created child device, when
creating the platform_device for the DWC3 core.

This does however not work with the upcoming change where the DWC3 core
is instantiated from the same platform_device as the glue, as the DRD
and host code will attempt to resolve their interrupts from the shared
device, and not the child device.

Work around this by merging the resources of the child device into the
glue device node, to present a single platform_device with all the
resources necessary.

Signed-off-by: Bjorn Andersson <quic_bjorande@quicinc.com>
---
 drivers/usb/dwc3/dwc3-qcom.c | 82 ++++++++++++++++++++++++++++++--------------
 1 file changed, 56 insertions(+), 26 deletions(-)

diff --git a/drivers/usb/dwc3/dwc3-qcom.c b/drivers/usb/dwc3/dwc3-qcom.c
index a31c3bc1f56e..7c810712d246 100644
--- a/drivers/usb/dwc3/dwc3-qcom.c
+++ b/drivers/usb/dwc3/dwc3-qcom.c
@@ -68,7 +68,6 @@ struct dwc3_qcom {
 	struct device		*dev;
 	void __iomem		*qscratch_base;
 	struct platform_device	*dwc_dev;
-	struct platform_device	*urs_usb;
 	struct clk		**clks;
 	int			num_clocks;
 	struct reset_control	*resets;
@@ -522,15 +521,13 @@ static void dwc3_qcom_select_utmi_clk(struct dwc3_qcom *qcom)
 static int dwc3_qcom_get_irq(struct platform_device *pdev,
 			     const char *name, int num)
 {
-	struct dwc3_qcom *qcom = platform_get_drvdata(pdev);
-	struct platform_device *pdev_irq = qcom->urs_usb ? qcom->urs_usb : pdev;
 	struct device_node *np = pdev->dev.of_node;
 	int ret;
 
 	if (np)
-		ret = platform_get_irq_byname_optional(pdev_irq, name);
+		ret = platform_get_irq_byname_optional(pdev, name);
 	else
-		ret = platform_get_irq_optional(pdev_irq, num);
+		ret = platform_get_irq_optional(pdev, num);
 
 	return ret;
 }
@@ -667,8 +664,6 @@ static int dwc3_qcom_acpi_register_core(struct platform_device *pdev)
 	struct dwc3_qcom	*qcom = platform_get_drvdata(pdev);
 	struct device		*dev = &pdev->dev;
 	struct resource		*res, *child_res = NULL;
-	struct platform_device	*pdev_irq = qcom->urs_usb ? qcom->urs_usb :
-							    pdev;
 	int			irq;
 	int			ret;
 
@@ -700,7 +695,7 @@ static int dwc3_qcom_acpi_register_core(struct platform_device *pdev)
 	child_res[0].end = child_res[0].start +
 		qcom->acpi_pdata->dwc3_core_base_size;
 
-	irq = platform_get_irq(pdev_irq, 0);
+	irq = platform_get_irq(pdev, 0);
 	if (irq < 0) {
 		ret = irq;
 		goto out;
@@ -766,31 +761,72 @@ static int dwc3_qcom_of_register_core(struct platform_device *pdev)
 	return ret;
 }
 
-static struct platform_device *
-dwc3_qcom_create_urs_usb_platdev(struct device *dev)
+static int dwc3_qcom_acpi_merge_urs_resources(struct platform_device *pdev)
 {
+	struct device *dev = &pdev->dev;
+	struct list_head resource_list;
+	struct resource_entry *rentry;
+	struct resource *resources;
 	struct fwnode_handle *fwh;
 	struct acpi_device *adev;
 	char name[8];
+	int count;
 	int ret;
 	int id;
+	int i;
 
 	/* Figure out device id */
 	ret = sscanf(fwnode_get_name(dev->fwnode), "URS%d", &id);
 	if (!ret)
-		return NULL;
+		return -EINVAL;
 
 	/* Find the child using name */
 	snprintf(name, sizeof(name), "USB%d", id);
 	fwh = fwnode_get_named_child_node(dev->fwnode, name);
 	if (!fwh)
-		return NULL;
+		return 0;
 
 	adev = to_acpi_device_node(fwh);
 	if (!adev)
-		return NULL;
+		return -EINVAL;
+
+	INIT_LIST_HEAD(&resource_list);
+
+	count = acpi_dev_get_resources(adev, &resource_list, NULL, NULL);
+	if (count <= 0)
+		return count;
+
+	count += pdev->num_resources;
+
+	resources = kcalloc(count, sizeof(*resources), GFP_KERNEL);
+	if (!resources) {
+		acpi_dev_free_resource_list(&resource_list);
+		return -ENOMEM;
+	}
+
+	memcpy(resources, pdev->resource, sizeof(struct resource) * pdev->num_resources);
+	count = pdev->num_resources;
+	list_for_each_entry(rentry, &resource_list, node) {
+		/* Avoid inserting duplicate entries, in case this is called more than once */
+		for (i = 0; i < count; i++) {
+			if (resource_type(&resources[i]) == resource_type(rentry->res) &&
+			    resources[i].start == rentry->res->start &&
+			    resources[i].end == rentry->res->end)
+				break;
+		}
+
+		if (i == count)
+			resources[count++] = *rentry->res;
+	}
 
-	return acpi_create_platform_device(adev, NULL);
+	ret = platform_device_add_resources(pdev, resources, count);
+	if (ret)
+		dev_err(&pdev->dev, "failed to add resources\n");
+
+	acpi_dev_free_resource_list(&resource_list);
+	kfree(resources);
+
+	return ret;
 }
 
 static int dwc3_qcom_probe(struct platform_device *pdev)
@@ -817,6 +853,12 @@ static int dwc3_qcom_probe(struct platform_device *pdev)
 			dev_err(&pdev->dev, "no supporting ACPI device data\n");
 			return -EINVAL;
 		}
+
+		if (qcom->acpi_pdata->is_urs) {
+			ret = dwc3_qcom_acpi_merge_urs_resources(pdev);
+			if (ret < 0)
+				goto clk_disable;
+		}
 	}
 
 	qcom->resets = devm_reset_control_array_get_optional_exclusive(dev);
@@ -857,18 +899,6 @@ static int dwc3_qcom_probe(struct platform_device *pdev)
 			qcom->acpi_pdata->qscratch_base_offset;
 		parent_res->end = parent_res->start +
 			qcom->acpi_pdata->qscratch_base_size;
-
-		if (qcom->acpi_pdata->is_urs) {
-			qcom->urs_usb = dwc3_qcom_create_urs_usb_platdev(dev);
-			if (IS_ERR_OR_NULL(qcom->urs_usb)) {
-				dev_err(dev, "failed to create URS USB platdev\n");
-				if (!qcom->urs_usb)
-					ret = -ENODEV;
-				else
-					ret = PTR_ERR(qcom->urs_usb);
-				goto clk_disable;
-			}
-		}
 	}
 
 	qcom->qscratch_base = devm_ioremap_resource(dev, parent_res);

-- 
2.25.1