Re: [PATCH 6/8] ACPI: property: Rename parsed MIPI DisCo for Imaging properties

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

On Tue, Jan 17, 2023 at 02:22:42PM +0200, Sakari Ailus wrote:
> MIPI DisCo for Imaging defines properties for sensor-adjacent devices such
> as EEPROM, LED flash or lens VCM as either device or sub-node references.
> This is compliant with existing DT definitions apart from property names.
> 
> Rename parsed MIPI-defined properties so drivers will have a unified view
> of them as defined in DT and already parsed by drivers. This can be done
> in-place as the MIPI-defined property strings are always longer than the
> DT one. This also results in loss of constness in parser function
> arguments.
> 
> Individual bindings to devices could define the references differently
> between MIPI DisCo for Imaging and DT, in terms of device or sub-node
> references. This will still need to be handled in the drivers themselves.

...

> +static const struct mipi_disco_prop {
> +	const char *mipi_prop;
> +	const char *dt_prop;
> +} mipi_disco_props[] = {
> +	{ "mipi-img-lens-focus", "lens-focus" },
> +	{ "mipi-img-flash-leds", "flash-leds" },
> +	{ "mipi-img-clock-frequency", "clock-frequency" },
> +	{ "mipi-img-led-max-current", "led-max-microamp" },
> +	{ "mipi-img-flash-max-current", "flash-max-microamp" },
> +	{ "mipi-img-flash-max-timeout", "flash-max-timeout-us" },
> +};

If we split this to 2 arrays (with static_assert() against their sizes)...

...

> +void acpi_properties_prepare_mipi(union acpi_object *elements)
> +{
> +	unsigned int i;
> +
> +	/* Replace MIPI DisCo for Imaging property names with DT equivalents. */
> +	for (i = 0; i < ARRAY_SIZE(mipi_disco_props); i++) {
> +		if (!strcmp(mipi_disco_props[i].mipi_prop,
> +			    elements[0].string.pointer)) {

...we can utilise match_string() here.

> +			WARN_ON(strscpy(elements[0].string.pointer,
> +					mipi_disco_props[i].dt_prop,
> +					elements[0].string.length) < 0);
> +			break;
> +		}
> +	}
> +}

...

>  	for (i = 0; i < properties->package.count; i++) {
> -		const union acpi_object *property;
> +		union acpi_object *property = &properties->package.elements[i];
> +		union acpi_object *elements = property->package.elements;
>  
> -		property = &properties->package.elements[i];
>  		/*
>  		 * Only two elements allowed, the first one must be a string and
>  		 * the second one has to satisfy certain conditions.
>  		 */
>  		if (property->package.count != 2
> -		    || property->package.elements[0].type != ACPI_TYPE_STRING
> -		    || !acpi_property_value_ok(&property->package.elements[1]))
> +		    || elements[0].type != ACPI_TYPE_STRING
> +		    || !acpi_property_value_ok(&elements[1]))

While at it you can mode ||:s on the respective previous lines.

>  			return false;
> +
> +		acpi_properties_prepare_mipi(elements);
>  	}

-- 
With Best Regards,
Andy Shevchenko