drivers/of: Specify parent node in of_fdt_unflatten_tree()

This adds one more argument to of_fdt_unflatten_tree() to specify
the parent node of the FDT blob that is going to be unflattened.
In the result, the function can be used to unflatten FDT blob that
represents device sub-tree in PowerNV PCI hotplug driver.

Cc: Jyri Sarha <jsarha@ti.com>
Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Jyri Sarha <jsarha@ti.com>
Signed-off-by: Rob Herring <robh@kernel.org>

diff --git a/drivers/gpu/drm/tilcdc/tilcdc_slave_compat.c b/drivers/gpu/drm/tilcdc/tilcdc_slave_compat.c
index 106679b..f9c79da 100644 (file)
--- a/drivers/gpu/drm/tilcdc/tilcdc_slave_compat.c
+++ b/drivers/gpu/drm/tilcdc/tilcdc_slave_compat.c
@@ -157,7 +157,7 @@ struct device_node * __init tilcdc_get_overlay(struct kfree_table *kft)
        if (!overlay_data || kfree_table_add(kft, overlay_data))
                return NULL;
 
-       of_fdt_unflatten_tree(overlay_data, &overlay);
+       of_fdt_unflatten_tree(overlay_data, NULL, &overlay);
        if (!overlay) {
                pr_warn("%s: Unfattening overlay tree failed\n", __func__);
                return NULL;

diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index 9c3e52d..0d53687 100644 (file)
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -450,11 +450,13 @@ static int unflatten_dt_nodes(const void *blob,
  * pointers of the nodes so the normal device-tree walking functions
  * can be used.
  * @blob: The blob to expand
+ * @dad: Parent device node
  * @mynodes: The device_node tree created by the call
  * @dt_alloc: An allocator that provides a virtual address to memory
  * for the resulting tree
  */
 static void __unflatten_device_tree(const void *blob,
+                            struct device_node *dad,
                             struct device_node **mynodes,
                             void * (*dt_alloc)(u64 size, u64 align))
 {
@@ -479,7 +481,7 @@ static void __unflatten_device_tree(const void *blob,
        }
 
        /* First pass, scan for size */
-       size = unflatten_dt_nodes(blob, NULL, NULL, NULL);
+       size = unflatten_dt_nodes(blob, NULL, dad, NULL);
        if (size < 0)
                return;
 
@@ -495,7 +497,7 @@ static void __unflatten_device_tree(const void *blob,
        pr_debug("  unflattening %p...\n", mem);
 
        /* Second pass, do actual unflattening */
-       unflatten_dt_nodes(blob, mem, NULL, mynodes);
+       unflatten_dt_nodes(blob, mem, dad, mynodes);
        if (be32_to_cpup(mem + size) != 0xdeadbeef)
                pr_warning("End of tree marker overwritten: %08x\n",
                           be32_to_cpup(mem + size));
@@ -512,6 +514,9 @@ static DEFINE_MUTEX(of_fdt_unflatten_mutex);
 
 /**
  * of_fdt_unflatten_tree - create tree of device_nodes from flat blob
+ * @blob: Flat device tree blob
+ * @dad: Parent device node
+ * @mynodes: The device tree created by the call
  *
  * unflattens the device-tree passed by the firmware, creating the
  * tree of struct device_node. It also fills the "name" and "type"
@@ -519,10 +524,11 @@ static DEFINE_MUTEX(of_fdt_unflatten_mutex);
  * can be used.
  */
 void of_fdt_unflatten_tree(const unsigned long *blob,
+                       struct device_node *dad,
                        struct device_node **mynodes)
 {
        mutex_lock(&of_fdt_unflatten_mutex);
-       __unflatten_device_tree(blob, mynodes, &kernel_tree_alloc);
+       __unflatten_device_tree(blob, dad, mynodes, &kernel_tree_alloc);
        mutex_unlock(&of_fdt_unflatten_mutex);
 }
 EXPORT_SYMBOL_GPL(of_fdt_unflatten_tree);
@@ -1195,7 +1201,7 @@ bool __init early_init_dt_scan(void *params)
  */
 void __init unflatten_device_tree(void)
 {
-       __unflatten_device_tree(initial_boot_params, &of_root,
+       __unflatten_device_tree(initial_boot_params, NULL, &of_root,
                                early_init_dt_alloc_memory_arch);
 
        /* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */

diff --git a/drivers/of/unittest.c b/drivers/of/unittest.c
index e986e6e..8c0f11c 100644 (file)
--- a/drivers/of/unittest.c
+++ b/drivers/of/unittest.c
@@ -921,7 +921,7 @@ static int __init unittest_data_add(void)
                        "not running tests\n", __func__);
                return -ENOMEM;
        }
-       of_fdt_unflatten_tree(unittest_data, &unittest_data_node);
+       of_fdt_unflatten_tree(unittest_data, NULL, &unittest_data_node);
        if (!unittest_data_node) {
                pr_warn("%s: No tree to attach; not running tests\n", __func__);
                return -ENODATA;

diff --git a/include/linux/of_fdt.h b/include/linux/of_fdt.h
index 2fbe868..1bffcbd 100644 (file)
--- a/include/linux/of_fdt.h
+++ b/include/linux/of_fdt.h
@@ -38,6 +38,7 @@ extern bool of_fdt_is_big_endian(const void *blob,
 extern int of_fdt_match(const void *blob, unsigned long node,
                        const char *const *compat);
 extern void of_fdt_unflatten_tree(const unsigned long *blob,
+                              struct device_node *dad,
                               struct device_node **mynodes);
 
 /* TBD: Temporary export of fdt globals - remove when code fully merged */