[PATCH v5 3/7] driver core: platform: provide platform_device_add_software_node()

[Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>]

The software node added to the platform device in
platform_device_register_full() is currently not removed on device
release. In order to fix this, we need to first convert all drivers that
use platform_device_alloc() and then assign a software node as the
primary firmware node to using device_add_software_node() for correct
reference counting.

To that end: provide platform_device_add_software_node() in line with
other existing helpers like platform_device_add_data().

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
---
 drivers/base/platform.c         | 25 ++++++++++++++++++++++++-
 include/linux/platform_device.h |  3 +++
 2 files changed, 27 insertions(+), 1 deletion(-)

diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index 18f33bec36726490255bc7ca3c4ab07d9b7606b0..f617e02b171f6e59a3c40504a71f8915a41e8514 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -613,6 +613,10 @@ static void platform_device_release(struct device *dev)
  *
  * Create a platform device object which can have other objects attached
  * to it, and which will have attached objects freed when it is released.
+ *
+ * Note: devices allocated with this function must not have the following
+ * members assigned manually: swnode, resources and dev->platform_data.
+ * Please use the provided helper interfaces.
  */
 struct platform_device *platform_device_alloc(const char *name, int id)
 {
@@ -687,6 +691,25 @@ int platform_device_add_data(struct platform_device *pdev, const void *data,
 }
 EXPORT_SYMBOL_GPL(platform_device_add_data);
 
+/**
+ * platform_device_add_software_node - add a software node to a platform device
+ * @pdev: platform device allocated with platform_device_alloc()
+ * @swnode: software node to assign to this device, does not need to be registered
+ *
+ * If this device is already associated with a primary firmware node, add the
+ * software node as the secondary firmware node. Otherwise, make it the primary
+ * firmware node. Register the software node if needed.
+ *
+ * Returns:
+ * 0 on success, negative error number on failure.
+ */
+int platform_device_add_software_node(struct platform_device *pdev,
+				      const struct software_node *swnode)
+{
+	return device_add_software_node(&pdev->dev, swnode);
+}
+EXPORT_SYMBOL_GPL(platform_device_add_software_node);
+
 /**
  * platform_device_add - add a platform device to device hierarchy
  * @pdev: platform device we're adding
@@ -881,7 +904,7 @@ struct platform_device *platform_device_register_full(const struct platform_devi
 		goto err;
 
 	if (pdevinfo->swnode) {
-		ret = device_add_software_node(&pdev->dev, pdevinfo->swnode);
+		ret = platform_device_add_software_node(pdev, pdevinfo->swnode);
 		if (ret)
 			goto err;
 	} else if (pdevinfo->properties) {
diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h
index 975400a472e30e2f98cc8f13bc36a63129bd4fcf..bd421506e98fc293c97121693e4bd18b703e41fa 100644
--- a/include/linux/platform_device.h
+++ b/include/linux/platform_device.h
@@ -19,6 +19,7 @@ struct irq_affinity;
 struct mfd_cell;
 struct property_entry;
 struct platform_device_id;
+struct software_node;
 
 struct platform_device {
 	const char	*name;
@@ -262,6 +263,8 @@ extern int platform_device_add_resources(struct platform_device *pdev,
 					 unsigned int num);
 extern int platform_device_add_data(struct platform_device *pdev,
 				    const void *data, size_t size);
+int platform_device_add_software_node(struct platform_device *pdev,
+				      const struct software_node *swnode);
 extern int platform_device_add(struct platform_device *pdev);
 extern void platform_device_del(struct platform_device *pdev);
 extern void platform_device_put(struct platform_device *pdev);

-- 
2.47.3