On Tue, Mar 3, 2026 at 2:13 PM Maxime Ripard mripard@redhat.com wrote:

On Tue, Mar 03, 2026 at 01:33:46PM +0100, Albert Esteve wrote:

...

Add a helper function wrapping internal reserved memory device_init call and expose it externally.

Use the new helper function within of_reserved_mem_device_init_by_idx().

Signed-off-by: Albert Esteve aesteve@redhat.com

drivers/of/of_reserved_mem.c | 27 +++++++++++++++++++++++---- include/linux/of_reserved_mem.h | 8 ++++++++ 2 files changed, 31 insertions(+), 4 deletions(-)

diff --git a/drivers/of/of_reserved_mem.c b/drivers/of/of_reserved_mem.c index 1fd28f8056108..3a350bef8f11e 100644 --- a/drivers/of/of_reserved_mem.c +++ b/drivers/of/of_reserved_mem.c @@ -605,6 +605,28 @@ struct rmem_assigned_device { static LIST_HEAD(of_rmem_assigned_device_list); static DEFINE_MUTEX(of_rmem_assigned_device_mutex);

+/**

• • of_reserved_mem_device_init_with_mem() - assign reserved memory region to

• •                                   given device
    

• • @dev: Pointer to the device to configure
• • @rmem: Reserved memory region to assign
• • This function assigns respective DMA-mapping operations based on the
• • reserved memory region already provided in @rmem to the @dev device,
• • without walking DT nodes.
• • Returns error code or zero on success.
• */

+int of_reserved_mem_device_init_with_mem(struct device *dev,

•                                  struct reserved_mem *rmem)
  

+{

• if (!dev || !rmem || !rmem->ops || !rmem->ops->device_init)
  

•         return -EINVAL;
  

• return rmem->ops->device_init(rmem, dev);
  

+} +EXPORT_SYMBOL_GPL(of_reserved_mem_device_init_with_mem);

/**

• of_reserved_mem_device_init_by_idx() - assign reserved memory region to

•                                 given device
  

@@ -643,14 +665,11 @@ int of_reserved_mem_device_init_by_idx(struct device *dev, rmem = of_reserved_mem_lookup(target); of_node_put(target);

• if (!rmem || !rmem->ops || !rmem->ops->device_init)
  

•         return -EINVAL;
  

• rd = kmalloc_obj(struct rmem_assigned_device);
  if (!rd)
          return -ENOMEM;
  
  

• ret = rmem->ops->device_init(rmem, dev);
  

• ret = of_reserved_mem_device_init_with_mem(dev, rmem);
  if (ret == 0) {
          rd->dev = dev;
          rd->rmem = rmem;
  

I think you need to take the allocation of rd, and everything below. Otherwise, your device, despite being attechd, wouldn't be listed anywhere.

True, I did not pay enough attention to that part. I will fix it in the next version.

Maxime