Re: [PATCH 1/3] software node: implement reference properties

[Andy Shevchenko <andriy.shevchenko@linux.intel.com>]

On Thu, Sep 05, 2019 at 09:38:07PM -0700, Dmitry Torokhov wrote:
> It is possible to store references to software nodes in the same fashion as
> other static properties, so that users do not need to define separate
> structures:
> 
> const struct software_node gpio_bank_b_node = {
> 	.name = "B",
> };

Why this can't be __initconst?

> const struct property_entry simone_key_enter_props[] __initconst = {
> 	PROPERTY_ENTRY_U32("linux,code", KEY_ENTER),
> 	PROPERTY_ENTRY_STRING("label", "enter"),
> 	PROPERTY_ENTRY_REF("gpios", &gpio_bank_b_node, 123, GPIO_ACTIVE_LOW),
> 	{ }
> };

So it's basically mimics the concept of phandle, right?

> +		ref_args = prop->is_array ?
> +				&prop->pointer.ref[index] : &prop->value.ref;

Better to do if with explicit 'if ()' as it's done in the rest of the code.

	if (prop->is_array)
		ref_args = ...;
	else
		ref_args = ...;

> -	DEV_PROP_MAX,
> +	DEV_PROP_MAX

It seems it wasn't ever used, so, can be dropped completely.

> @@ -240,6 +255,7 @@ struct property_entry {
>  			const u32 *u32_data;
>  			const u64 *u64_data;
>  			const char * const *str;
> +			const struct software_node_ref_args *ref;
>  		} pointer;
>  		union {
>  			u8 u8_data;
> @@ -247,6 +263,7 @@ struct property_entry {
>  			u32 u32_data;
>  			u64 u64_data;
>  			const char *str;
> +			struct software_node_ref_args ref;

Hmm... This bumps the size of union a lot for each existing property_entry.
Is there any other way? Maybe we can keep pointer and allocate memory for it
when copying?

>  		} value;

> +#define PROPERTY_ENTRY_REF_ARRAY(_name_, _val_)			\
> +(struct property_entry) {					\
> +	.name = _name_,						\
> +	.length = ARRAY_SIZE(_val_) *				\
> +			sizeof(struct software_node_ref_args),	\

I would rather leave it on one line and shift right all \:s in this macro.

> +	.is_array = true,					\
> +	.type = DEV_PROP_REF,					\
> +	.pointer.ref = _val_,					\
> +}
> +

> +#define PROPERTY_ENTRY_REF(_name_, _ref_, ...)			\
> +(struct property_entry) {					\
> +	.name = _name_,						\
> +	.length = sizeof(struct software_node_ref_args),	\
> +	.type = DEV_PROP_REF,					\
> +	.value.ref.node = _ref_,				\

> +	.value.ref.nargs =					\
> +		ARRAY_SIZE(((u64[]){ 0, ##__VA_ARGS__ })) - 1,	\

Ditto.

> +	.value.ref.args = { __VA_ARGS__ },			\
> +}

-- 
With Best Regards,
Andy Shevchenko