Driver registration fails on SOC imx8mn as its supplier, the clock
control module, is not ready. Since platform_driver_probe(), as
reported by its description, is incompatible with deferred probing,
we have to use platform_driver_register().

The addition of the `_probe' suffix to the `mxs_dma_driver' variable was
suggested by the following modpost warning:

WARNING: modpost: vmlinux.o(.data+0xa3900): Section mismatch in reference from the variable mxs_dma_driver to the function .init.text:mxs_dma_probe()
The variable mxs_dma_driver references
the function __init mxs_dma_probe()
If the reference is valid then annotate the
variable with __init* or __refdata (see linux/init.h) or name the variable:
*_template, *_timer, *_sht, *_ops, *_probe, *_probe_one, *_console

Fixes: a580b8c5429a ("dmaengine: mxs-dma: add dma support for i.MX23/28")
Co-developed-by: Michael Trimarchi <michael@amarulasolutions.com>
Signed-off-by: Michael Trimarchi <michael@amarulasolutions.com>
Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Cc: stable@vger.kernel.org

---

Changes in v4:
- Restore __init in front of mxs_dma_probe() definition.
- Rename the mxs_dma_driver variable to mxs_dma_driver_probe.
- Update the commit message.
- Use builtin_platform_driver() instead of module_platform_driver().

Changes in v3:
- Restore __init in front of mxs_dma_init() definition.

Changes in v2:
- Add the tag "Cc: stable@vger.kernel.org" in the sign-off area.

 drivers/dma/mxs-dma.c | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/drivers/dma/mxs-dma.c b/drivers/dma/mxs-dma.c
index 994fc4d2aca4..4c878bf1e092 100644
--- a/drivers/dma/mxs-dma.c
+++ b/drivers/dma/mxs-dma.c
@@ -834,15 +834,11 @@ static int __init mxs_dma_probe(struct platform_device *pdev)
 	return 0;
 }
 
-static struct platform_driver mxs_dma_driver = {
+static struct platform_driver mxs_dma_driver_probe = {
 	.driver		= {
 		.name	= "mxs-dma",
 		.of_match_table = mxs_dma_dt_ids,
 	},
+	.probe = mxs_dma_probe,
 };
-
-static int __init mxs_dma_module_init(void)
-{
-	return platform_driver_probe(&mxs_dma_driver, mxs_dma_probe);
-}
-subsys_initcall(mxs_dma_module_init);
+builtin_platform_driver(mxs_dma_driver_probe);
-- 
2.32.0

On 21-06-22, 14:36, Dario Binacchi wrote:
> Driver registration fails on SOC imx8mn as its supplier, the clock
> control module, is not ready. Since platform_driver_probe(), as
> reported by its description, is incompatible with deferred probing,
> we have to use platform_driver_register().

Pls revise title to reflect the changes added and not the effect

Btw lots of driver work like this, they use platform_driver_probe() but
make the clk and other resources do earlier init levels. This change is
fine too...

> The addition of the `_probe' suffix to the `mxs_dma_driver' variable was
> suggested by the following modpost warning:
> 
> WARNING: modpost: vmlinux.o(.data+0xa3900): Section mismatch in reference from the variable mxs_dma_driver to the function .init.text:mxs_dma_probe()
> The variable mxs_dma_driver references
> the function __init mxs_dma_probe()
> If the reference is valid then annotate the
> variable with __init* or __refdata (see linux/init.h) or name the variable:
> *_template, *_timer, *_sht, *_ops, *_probe, *_probe_one, *_console

that should be always a separate patch

> 
> Fixes: a580b8c5429a ("dmaengine: mxs-dma: add dma support for i.MX23/28")
> Co-developed-by: Michael Trimarchi <michael@amarulasolutions.com>
> Signed-off-by: Michael Trimarchi <michael@amarulasolutions.com>
> Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
> Cc: stable@vger.kernel.org
> 
> ---
> 
> Changes in v4:
> - Restore __init in front of mxs_dma_probe() definition.
> - Rename the mxs_dma_driver variable to mxs_dma_driver_probe.
> - Update the commit message.
> - Use builtin_platform_driver() instead of module_platform_driver().
> 
> Changes in v3:
> - Restore __init in front of mxs_dma_init() definition.
> 
> Changes in v2:
> - Add the tag "Cc: stable@vger.kernel.org" in the sign-off area.
> 
>  drivers/dma/mxs-dma.c | 10 +++-------
>  1 file changed, 3 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/dma/mxs-dma.c b/drivers/dma/mxs-dma.c
> index 994fc4d2aca4..4c878bf1e092 100644
> --- a/drivers/dma/mxs-dma.c
> +++ b/drivers/dma/mxs-dma.c
> @@ -834,15 +834,11 @@ static int __init mxs_dma_probe(struct platform_device *pdev)
>  	return 0;
>  }
>  
> -static struct platform_driver mxs_dma_driver = {
> +static struct platform_driver mxs_dma_driver_probe = {
>  	.driver		= {
>  		.name	= "mxs-dma",
>  		.of_match_table = mxs_dma_dt_ids,
>  	},
> +	.probe = mxs_dma_probe,
>  };
> -
> -static int __init mxs_dma_module_init(void)
> -{
> -	return platform_driver_probe(&mxs_dma_driver, mxs_dma_probe);
> -}
> -subsys_initcall(mxs_dma_module_init);
> +builtin_platform_driver(mxs_dma_driver_probe);
> -- 
> 2.32.0

-- 
~Vinod