[PATCHv5 6/7] base: platform: name the device already during allocation

[Heikki Krogerus <heikki.krogerus@linux.intel.com>]

The device name is usually required when assigning resources
like clocks to platform devices. The problem is that the
device name is not know before platform_device_add is called
and that can be too late as the drivers may have already
requested the resources when the function returns. By naming
the device already in platform_device_alloc, the resources
can be assigned before platform_device_add is called.

This change allows different kinds of probe drivers to pass
forward their resources to the actual driver. The first
place where we need it is dwc3 controllers host glue code
(drivers/usb/dwc3/host.c) to pass the phy's to xhci.

Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/base/platform.c | 69 +++++++++++++++++++++++++++++--------------------
 1 file changed, 41 insertions(+), 28 deletions(-)

diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index cdb6c07..d2217f3 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -195,11 +195,41 @@ void platform_device_put(struct platform_device *pdev)
 }
 EXPORT_SYMBOL_GPL(platform_device_put);
 
+static int pdev_set_name(struct platform_device *pdev)
+{
+	int ret;
+
+	switch (pdev->id) {
+	default:
+		return dev_set_name(&pdev->dev, "%s.%d", pdev->name,  pdev->id);
+	case PLATFORM_DEVID_NONE:
+		return dev_set_name(&pdev->dev, "%s", pdev->name);
+	case PLATFORM_DEVID_AUTO:
+		/*
+		 * Automatically allocated device ID. We mark it as such so
+		 * that we remember it must be freed, and we append a suffix
+		 * to avoid namespace collision with explicit IDs.
+		 */
+		ret = ida_simple_get(&platform_devid_ida, 0, 0, GFP_KERNEL);
+		if (ret < 0)
+			return ret;
+		pdev->id = ret;
+		pdev->id_auto = true;
+		return dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name,
+				    pdev->id);
+	}
+
+	return 0;
+}
+
 static void platform_device_release(struct device *dev)
 {
 	struct platform_object *pa = container_of(dev, struct platform_object,
 						  pdev.dev);
 
+	if (pa->pdev.id_auto)
+		ida_simple_remove(&platform_devid_ida, pa->pdev.id);
+
 	of_device_node_put(&pa->pdev.dev);
 	kfree(pa->pdev.dev.platform_data);
 	kfree(pa->pdev.mfd_cell);
@@ -228,6 +258,10 @@ struct platform_device *platform_device_alloc(const char *name, int id)
 		device_initialize(&pa->pdev.dev);
 		pa->pdev.dev.release = platform_device_release;
 		arch_setup_pdev_archdata(&pa->pdev);
+		if (pdev_set_name(&pa->pdev)) {
+			kfree(pa);
+			return NULL;
+		}
 	}
 
 	return pa ? &pa->pdev : NULL;
@@ -308,28 +342,6 @@ int platform_device_add(struct platform_device *pdev)
 
 	pdev->dev.bus = &platform_bus_type;
 
-	switch (pdev->id) {
-	default:
-		dev_set_name(&pdev->dev, "%s.%d", pdev->name,  pdev->id);
-		break;
-	case PLATFORM_DEVID_NONE:
-		dev_set_name(&pdev->dev, "%s", pdev->name);
-		break;
-	case PLATFORM_DEVID_AUTO:
-		/*
-		 * Automatically allocated device ID. We mark it as such so
-		 * that we remember it must be freed, and we append a suffix
-		 * to avoid namespace collision with explicit IDs.
-		 */
-		ret = ida_simple_get(&platform_devid_ida, 0, 0, GFP_KERNEL);
-		if (ret < 0)
-			goto err_out;
-		pdev->id = ret;
-		pdev->id_auto = true;
-		dev_set_name(&pdev->dev, "%s.%d.auto", pdev->name, pdev->id);
-		break;
-	}
-
 	for (i = 0; i < pdev->num_resources; i++) {
 		struct resource *p, *r = &pdev->resource[i];
 
@@ -372,7 +384,6 @@ int platform_device_add(struct platform_device *pdev)
 			release_resource(r);
 	}
 
- err_out:
 	return ret;
 }
 EXPORT_SYMBOL_GPL(platform_device_add);
@@ -392,11 +403,6 @@ void platform_device_del(struct platform_device *pdev)
 	if (pdev) {
 		device_del(&pdev->dev);
 
-		if (pdev->id_auto) {
-			ida_simple_remove(&platform_devid_ida, pdev->id);
-			pdev->id = PLATFORM_DEVID_AUTO;
-		}
-
 		for (i = 0; i < pdev->num_resources; i++) {
 			struct resource *r = &pdev->resource[i];
 			unsigned long type = resource_type(r);
@@ -414,8 +420,15 @@ EXPORT_SYMBOL_GPL(platform_device_del);
  */
 int platform_device_register(struct platform_device *pdev)
 {
+	int ret;
+
 	device_initialize(&pdev->dev);
 	arch_setup_pdev_archdata(pdev);
+
+	ret = pdev_set_name(pdev);
+	if (ret)
+		return ret;
+
 	return platform_device_add(pdev);
 }
 EXPORT_SYMBOL_GPL(platform_device_register);
-- 
2.1.3