Re: [PATCH v2] drivers: of/base: move of_init to driver_init

[Robert Schwebel <r.schwebel@pengutronix.de>]

Hi Sudeep,

On Thu, May 14, 2015 at 03:28:24PM +0100, Sudeep Holla wrote:
> Commit 5590f3196b29 ("drivers/core/of: Add symlink to device-tree from
> devices with an OF node") adds the symlink `of_node` for each device
> pointing to it's device tree node while creating/initialising it.
> 
> However the devicetree sysfs is created and setup in of_init which is
> executed at core_initcall level. For all the devices created before
> of_init, the following error is thrown:
> 	"Error -2(-ENOENT) creating of_node link"
> 
> Like many other components in driver model, initialize the sysfs support
> for OF/devicetree from driver_init so that it's ready before any devices
> are created.
> 
> Fixes: 5590f3196b29 ("drivers/core/of: Add symlink to device-tree from
> 	devices with an OF node")
> Suggested-by: Rob Herring <robh+dt@kernel.org>
> Cc: Grant Likely <grant.likely@linaro.org>
> Cc: Rob Herring <robh+dt@kernel.org>
> Cc: Pawel Moll <pawel.moll@arm.com>
> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
> ---
>  drivers/base/init.c | 2 ++
>  drivers/of/base.c   | 8 +++-----
>  include/linux/of.h  | 6 ++++++
>  3 files changed, 11 insertions(+), 5 deletions(-)
> 
> Changes v1->v2:
> 	- renamed of_init to of_core_init to avoid collision with
> 	  PPC nouveau drm driver
> 
> diff --git a/drivers/base/init.c b/drivers/base/init.c
> index da033d3bab3c..48c0e220acc0 100644
> --- a/drivers/base/init.c
> +++ b/drivers/base/init.c
> @@ -8,6 +8,7 @@
>  #include <linux/device.h>
>  #include <linux/init.h>
>  #include <linux/memory.h>
> +#include <linux/of.h>
> 
>  #include "base.h"
> 
> @@ -34,4 +35,5 @@ void __init driver_init(void)
>  	cpu_dev_init();
>  	memory_dev_init();
>  	container_dev_init();
> +	of_core_init();
>  }
> diff --git a/drivers/of/base.c b/drivers/of/base.c
> index 99764db0875a..f0650265febf 100644
> --- a/drivers/of/base.c
> +++ b/drivers/of/base.c
> @@ -189,7 +189,7 @@ int __of_attach_node_sysfs(struct device_node *np)
>  	return 0;
>  }
> 
> -static int __init of_init(void)
> +void __init of_core_init(void)
>  {
>  	struct device_node *np;
> 
> @@ -198,7 +198,8 @@ static int __init of_init(void)
>  	of_kset = kset_create_and_add("devicetree", NULL, firmware_kobj);
>  	if (!of_kset) {
>  		mutex_unlock(&of_mutex);
> -		return -ENOMEM;
> +		pr_err("devicetree: failed to register existing nodes\n");
> +		return;
>  	}
>  	for_each_of_allnodes(np)
>  		__of_attach_node_sysfs(np);
> @@ -207,10 +208,7 @@ static int __init of_init(void)
>  	/* Symlink in /proc as required by userspace ABI */
>  	if (of_root)
>  		proc_symlink("device-tree", NULL, "/sys/firmware/devicetree/base");
> -
> -	return 0;
>  }
> -core_initcall(of_init);
> 
>  static struct property *__of_find_property(const struct device_node *np,
>  					   const char *name, int *lenp)
> diff --git a/include/linux/of.h b/include/linux/of.h
> index ddeaae6d2083..b871ff9d81d7 100644
> --- a/include/linux/of.h
> +++ b/include/linux/of.h
> @@ -121,6 +121,8 @@ extern struct device_node *of_stdout;
>  extern raw_spinlock_t devtree_lock;
> 
>  #ifdef CONFIG_OF
> +void of_core_init(void);
> +
>  static inline bool is_of_node(struct fwnode_handle *fwnode)
>  {
>  	return fwnode && fwnode->type == FWNODE_OF;
> @@ -376,6 +378,10 @@ bool of_console_check(struct device_node *dn, char *name, int index);
> 
>  #else /* CONFIG_OF */
> 
> +static inline void of_core_init(void)
> +{
> +}
> +
>  static inline bool is_of_node(struct fwnode_handle *fwnode)
>  {
>  	return false;
> --
> 1.9.1
> 
> --
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> 

Works on vexpress (qemu), thanks!

Tested-by: Robert Schwebel <r.schwebel@pengutronix.de>

rsc
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