Add a managed API, devm_of_dma_controller_register(), to simplify DMA
engine controller registration by automatically handling resource
cleanup.

Signed-off-by: Frank Li <Frank.Li@nxp.com>
---
 include/linux/of_dma.h | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/include/linux/of_dma.h b/include/linux/of_dma.h
index fd706cdf255c61c82ce30ef9a2c44930bef34bc8..c630b23fdd1313168e2362415093f106d6a66c46 100644
--- a/include/linux/of_dma.h
+++ b/include/linux/of_dma.h
@@ -38,6 +38,26 @@ extern int of_dma_controller_register(struct device_node *np,
 		void *data);
 extern void of_dma_controller_free(struct device_node *np);
 
+static void __of_dma_controller_free(void *np)
+{
+	of_dma_controller_free(np);
+}
+
+static inline int
+devm_of_dma_controller_register(struct device *dev, struct device_node *np,
+				struct dma_chan *(*of_dma_xlate)
+				(struct of_phandle_args *, struct of_dma *),
+				void *data)
+{
+	int ret;
+
+	ret = of_dma_controller_register(np, of_dma_xlate, data);
+	if (ret)
+		return ret;
+
+	return devm_add_action_or_reset(dev, __of_dma_controller_free, np);
+}
+
 extern int of_dma_router_register(struct device_node *np,
 		void *(*of_dma_route_allocate)
 		(struct of_phandle_args *, struct of_dma *),
@@ -64,6 +84,15 @@ static inline void of_dma_controller_free(struct device_node *np)
 {
 }
 
+static inline
+devm_of_dma_controller_register(struct device *dev, struct device_node *np,
+				struct dma_chan *(*of_dma_xlate)
+				(struct of_phandle_args *, struct of_dma *),
+				void *data)
+{
+	return -ENODEV;
+}
+
 static inline int of_dma_router_register(struct device_node *np,
 		void *(*of_dma_route_allocate)
 		(struct of_phandle_args *, struct of_dma *),

-- 
2.34.1

Hi Frank,

kernel test robot noticed the following build errors:

[auto build test ERROR on 8f0b4cce4481fb22653697cced8d0d04027cb1e8]

url:    https://github.com/intel-lab-lkp/linux/commits/Frank-Li/dmaengine-of_dma-Add-devm_of_dma_controller_register/20260115-063955
base:   8f0b4cce4481fb22653697cced8d0d04027cb1e8
patch link:    https://lore.kernel.org/r/20260114-mxsdma-module-v1-1-9b2a9eaa4226%40nxp.com
patch subject: [PATCH 01/13] dmaengine: of_dma: Add devm_of_dma_controller_register()
config: x86_64-randconfig-r071-20260115 (https://download.01.org/0day-ci/archive/20260115/202601151942.cEs9s8Tj-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.4.0-5) 12.4.0
smatch version: v0.5.0-8985-g2614ff1a
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260115/202601151942.cEs9s8Tj-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202601151942.cEs9s8Tj-lkp@intel.com/

All errors (new ones prefixed by >>):

   In file included from drivers/tty/serial/fsl_lpuart.c:22:
>> include/linux/of_dma.h:88:1: error: return type defaults to 'int' [-Werror=implicit-int]
      88 | devm_of_dma_controller_register(struct device *dev, struct device_node *np,
         | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   cc1: some warnings being treated as errors


vim +/int +88 include/linux/of_dma.h

    86	
    87	static inline
  > 88	devm_of_dma_controller_register(struct device *dev, struct device_node *np,
    89					struct dma_chan *(*of_dma_xlate)
    90					(struct of_phandle_args *, struct of_dma *),
    91					void *data)
    92	{
    93		return -ENODEV;
    94	}
    95	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

Hi Frank,

kernel test robot noticed the following build errors:

[auto build test ERROR on 8f0b4cce4481fb22653697cced8d0d04027cb1e8]

url:    https://github.com/intel-lab-lkp/linux/commits/Frank-Li/dmaengine-of_dma-Add-devm_of_dma_controller_register/20260115-063955
base:   8f0b4cce4481fb22653697cced8d0d04027cb1e8
patch link:    https://lore.kernel.org/r/20260114-mxsdma-module-v1-1-9b2a9eaa4226%40nxp.com
patch subject: [PATCH 01/13] dmaengine: of_dma: Add devm_of_dma_controller_register()
config: x86_64-randconfig-161-20260115 (https://download.01.org/0day-ci/archive/20260115/202601151857.D1ikP7GO-lkp@intel.com/config)
compiler: clang version 20.1.8 (https://github.com/llvm/llvm-project 87f0227cb60147a26a1eeb4fb06e3b505e9c7261)
rustc: rustc 1.88.0 (6b00bc388 2025-06-23)
smatch version: v0.5.0-8985-g2614ff1a
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260115/202601151857.D1ikP7GO-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202601151857.D1ikP7GO-lkp@intel.com/

All errors (new ones prefixed by >>):

   In file included from drivers/dma/dmaengine.c:54:
>> include/linux/of_dma.h:88:1: error: type specifier missing, defaults to 'int'; ISO C99 and later do not support implicit int [-Wimplicit-int]
      87 | static inline
         | ~~~~~~~~~~~~~
         | int
      88 | devm_of_dma_controller_register(struct device *dev, struct device_node *np,
         | ^
   1 error generated.


vim +/int +88 include/linux/of_dma.h

    86	
    87	static inline
  > 88	devm_of_dma_controller_register(struct device *dev, struct device_node *np,
    89					struct dma_chan *(*of_dma_xlate)
    90					(struct of_phandle_args *, struct of_dma *),
    91					void *data)
    92	{
    93		return -ENODEV;
    94	}
    95	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki

On Thu, Jan 15, 2026 at 12:34 AM Frank Li <Frank.Li@nxp.com> wrote:
>
> Add a managed API, devm_of_dma_controller_register(), to simplify DMA
> engine controller registration by automatically handling resource
> cleanup.

<snip>

> +static inline
> +devm_of_dma_controller_register(struct device *dev, struct device_node *np,

static inline int?