[v2,04/21] of: Move of_modalias() to module.c

  Create a specific .c file for of related module handling.
Move of_modalias() inside as a first step.

Suggested-by: Rob Herring <robh+dt@kernel.org>
Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
---
 drivers/of/Makefile |  2 +-
 drivers/of/device.c | 37 -------------------------------------
 drivers/of/module.c | 43 +++++++++++++++++++++++++++++++++++++++++++
 include/linux/of.h  |  8 ++++++++
 4 files changed, 52 insertions(+), 38 deletions(-)
 create mode 100644 drivers/of/module.c
  

On Tue, Mar 07, 2023 at 05:53:42PM +0100, Miquel Raynal wrote:
> Create a specific .c file for of related module handling.
> Move of_modalias() inside as a first step.

Perhaps a comment as to why it needs to be public? Or is it just shared 
within the DT core? If so, we have of_private.h for that.

> 
> Suggested-by: Rob Herring <robh+dt@kernel.org>
> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
> ---
>  drivers/of/Makefile |  2 +-
>  drivers/of/device.c | 37 -------------------------------------
>  drivers/of/module.c | 43 +++++++++++++++++++++++++++++++++++++++++++
>  include/linux/of.h  |  8 ++++++++
>  4 files changed, 52 insertions(+), 38 deletions(-)
>  create mode 100644 drivers/of/module.c
> 
> diff --git a/drivers/of/Makefile b/drivers/of/Makefile
> index e0360a44306e..ae9923fd2940 100644
> --- a/drivers/of/Makefile
> +++ b/drivers/of/Makefile
> @@ -1,5 +1,5 @@
>  # SPDX-License-Identifier: GPL-2.0
> -obj-y = base.o device.o platform.o property.o
> +obj-y = base.o device.o module.o platform.o property.o
>  obj-$(CONFIG_OF_KOBJ) += kobj.o
>  obj-$(CONFIG_OF_DYNAMIC) += dynamic.o
>  obj-$(CONFIG_OF_FLATTREE) += fdt.o
> diff --git a/drivers/of/device.c b/drivers/of/device.c
> index 2bbb67798916..44f1f2ef12b7 100644
> --- a/drivers/of/device.c
> +++ b/drivers/of/device.c
> @@ -1,5 +1,4 @@
>  // SPDX-License-Identifier: GPL-2.0
> -#include <linux/string.h>
>  #include <linux/kernel.h>
>  #include <linux/of.h>
>  #include <linux/of_device.h>
> @@ -248,42 +247,6 @@ const void *of_device_get_match_data(const struct device *dev)
>  }
>  EXPORT_SYMBOL(of_device_get_match_data);
>  
> -static ssize_t of_modalias(struct device_node *np, char *str, ssize_t len)
> -{
> -	const char *compat;
> -	char *c;
> -	struct property *p;
> -	ssize_t csize;
> -	ssize_t tsize;
> -
> -	/* Name & Type */
> -	/* %p eats all alphanum characters, so %c must be used here */
> -	csize = snprintf(str, len, "of:N%pOFn%c%s", np, 'T',
> -			 of_node_get_device_type(np));
> -	tsize = csize;
> -	len -= csize;
> -	if (str)
> -		str += csize;
> -
> -	of_property_for_each_string(np, "compatible", p, compat) {
> -		csize = strlen(compat) + 1;
> -		tsize += csize;
> -		if (csize > len)
> -			continue;
> -
> -		csize = snprintf(str, len, "C%s", compat);
> -		for (c = str; c; ) {
> -			c = strchr(c, ' ');
> -			if (c)
> -				*c++ = '_';
> -		}
> -		len -= csize;
> -		str += csize;
> -	}
> -
> -	return tsize;
> -}
> -
>  int of_device_request_module(struct device *dev)
>  {
>  	char *str;
> diff --git a/drivers/of/module.c b/drivers/of/module.c
> new file mode 100644
> index 000000000000..9c6a53f32c0f
> --- /dev/null
> +++ b/drivers/of/module.c
> @@ -0,0 +1,43 @@
> +// SPDX-License-Identifier: GPL-2.0+

Existing license was GPL-2.0 (-only).

> +/*
> + * Linux kernel module helpers.
> + */
> +
> +#include <linux/of.h>
> +#include <linux/string.h>
> +
> +ssize_t of_modalias(struct device_node *np, char *str, ssize_t len)
> +{
> +	const char *compat;
> +	char *c;
> +	struct property *p;
> +	ssize_t csize;
> +	ssize_t tsize;
> +
> +	/* Name & Type */
> +	/* %p eats all alphanum characters, so %c must be used here */
> +	csize = snprintf(str, len, "of:N%pOFn%c%s", np, 'T',
> +			 of_node_get_device_type(np));
> +	tsize = csize;
> +	len -= csize;
> +	if (str)
> +		str += csize;
> +
> +	of_property_for_each_string(np, "compatible", p, compat) {
> +		csize = strlen(compat) + 1;
> +		tsize += csize;
> +		if (csize > len)
> +			continue;
> +
> +		csize = snprintf(str, len, "C%s", compat);
> +		for (c = str; c; ) {
> +			c = strchr(c, ' ');
> +			if (c)
> +				*c++ = '_';
> +		}
> +		len -= csize;
> +		str += csize;
> +	}
> +
> +	return tsize;
> +}
> diff --git a/include/linux/of.h b/include/linux/of.h
> index fc7ada57df33..1372f8647272 100644
> --- a/include/linux/of.h
> +++ b/include/linux/of.h
> @@ -373,6 +373,9 @@ extern int of_parse_phandle_with_args_map(const struct device_node *np,
>  extern int of_count_phandle_with_args(const struct device_node *np,
>  	const char *list_name, const char *cells_name);
>  
> +/* module functions */
> +extern ssize_t of_modalias(struct device_node *np, char *str, ssize_t len);
> +
>  /* phandle iterator functions */
>  extern int of_phandle_iterator_init(struct of_phandle_iterator *it,
>  				    const struct device_node *np,
> @@ -730,6 +733,11 @@ static inline int of_count_phandle_with_args(const struct device_node *np,
>  	return -ENOSYS;
>  }
>  
> +static inline ssize_t of_modalias(struct device_node *np, char *str, ssize_t len)
> +{
> +	return -ENODEV;
> +}
> +
>  static inline int of_phandle_iterator_init(struct of_phandle_iterator *it,
>  					   const struct device_node *np,
>  					   const char *list_name,
> -- 
> 2.34.1
>
  

Hi Rob,

robh@kernel.org wrote on Tue, 7 Mar 2023 18:23:06 -0600:

> On Tue, Mar 07, 2023 at 05:53:42PM +0100, Miquel Raynal wrote:
> > Create a specific .c file for of related module handling.
> > Move of_modalias() inside as a first step.  
> 
> Perhaps a comment as to why it needs to be public? Or is it just shared 
> within the DT core? If so, we have of_private.h for that.

Good point. This helper is actually only used internally (was static
before). At first I wanted to convert all users to use the "new" OF
module-related helpers, but unfortunately, the "dev->of_node_reused"
check makes this impossible. I thus need to keep a few users of
of_modalias() in of_device.h in the coming patches. I could move
of_modalias() to of_private.h but that would mean exposing all the
internals and private definitions to the drivers including of_device.h,
which seemed extremely unsatisfying to me.

I've updated the commit log with:

    The helper is exposed through of.h even though it is only used by core
    files because the users from device.c will soon be split into an OF-only
    helper in module.c as well as a device-oriented inline helper in
    of_device.h. Putting this helper in of_private.h would require to
    include of_private.h from of_device.h, which is not acceptable.

> 
> > 
> > Suggested-by: Rob Herring <robh+dt@kernel.org>
> > Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
> > ---
> >  drivers/of/Makefile |  2 +-
> >  drivers/of/device.c | 37 -------------------------------------
> >  drivers/of/module.c | 43 +++++++++++++++++++++++++++++++++++++++++++
> >  include/linux/of.h  |  8 ++++++++
> >  4 files changed, 52 insertions(+), 38 deletions(-)
> >  create mode 100644 drivers/of/module.c
> > 
> > diff --git a/drivers/of/Makefile b/drivers/of/Makefile
> > index e0360a44306e..ae9923fd2940 100644
> > --- a/drivers/of/Makefile
> > +++ b/drivers/of/Makefile
> > @@ -1,5 +1,5 @@
> >  # SPDX-License-Identifier: GPL-2.0
> > -obj-y = base.o device.o platform.o property.o
> > +obj-y = base.o device.o module.o platform.o property.o
> >  obj-$(CONFIG_OF_KOBJ) += kobj.o
> >  obj-$(CONFIG_OF_DYNAMIC) += dynamic.o
> >  obj-$(CONFIG_OF_FLATTREE) += fdt.o
> > diff --git a/drivers/of/device.c b/drivers/of/device.c
> > index 2bbb67798916..44f1f2ef12b7 100644
> > --- a/drivers/of/device.c
> > +++ b/drivers/of/device.c

[...]

> > diff --git a/drivers/of/module.c b/drivers/of/module.c
> > new file mode 100644
> > index 000000000000..9c6a53f32c0f
> > --- /dev/null
> > +++ b/drivers/of/module.c
> > @@ -0,0 +1,43 @@
> > +// SPDX-License-Identifier: GPL-2.0+  
> 
> Existing license was GPL-2.0 (-only).

Oh right, I took the license from base.c, you're right I should have
taken the one from device.c.

Thanks,
Miquèl