On Tue, Sep 18, 2018 at 10:04:18AM -0700, Dmitry Torokhov wrote:

I am not sure how that would work, as there are multiple properties in
that child array, so we can't simply take the first entry or assume that
all entries describe GPIOs. Here is the fuller example:

static const struct property_entry simone_key_enter_props[] __initconst = {
	PROPERTY_ENTRY_U32("linux,code",	KEY_ENTER),
	PROPERTY_ENTRY_STRING("label",		"enter"),
	PROPERTY_ENTRY_STRING("gpios",		"enter-gpios"),
	{ }
};

static const struct property_entry simone_key_up_props[] __initconst = {
	PROPERTY_ENTRY_U32("linux,code",	KEY_UP),
	PROPERTY_ENTRY_STRING("label",		"up"),
	PROPERTY_ENTRY_STRING("gpios",		"up-gpios"),
	{ }
};

static const struct property_entry simone_key_up_props[] __initconst = {
	PROPERTY_ENTRY_U32("linux,code",	KEY_LEFT),
	PROPERTY_ENTRY_STRING("label",		"left"),
	PROPERTY_ENTRY_STRING("gpios",		"left-gpios"),
	{ }
};

static const struct property_entry simone_key_props[] __initconst = {
	/* There are no properties at device level on this device */
	{ }
};

static struct gpiod_lookup_table simone_keys_gpiod_table = {
	.dev_id = "gpio-keys",
	.table = {
		/* Use local offsets on gpiochip/port "B" */
		GPIO_LOOKUP_IDX("B", 0, "enter-gpios", 0, GPIO_ACTIVE_LOW),
		GPIO_LOOKUP_IDX("B", 1, "up-gpios", 1, GPIO_ACTIVE_LOW),
		GPIO_LOOKUP_IDX("B", 2, "left-gpios", 2, GPIO_ACTIVE_LOW),
	},
};

static struct platform_device simone_keys_device = {
	.name = "gpio-keys",
	.id = -1,
};

static void __init simone_init_machine(void)
{
	...
	gpiod_add_lookup_table(&simone_keys_gpiod_table);
	device_add_properties(&simone_keys_device.dev,
			      simone_keys_device_props);
	device_add_child_properties(&simone_keys_device.dev,
				    dev_fwnode(&simone_keys_device.dev),
				    simone_key_enter_props);
	device_add_child_properties(&simone_keys_device.dev,
				    dev_fwnode(&simone_keys_device.dev),
				    simone_key_up_props);
	device_add_child_properties(&simone_keys_device.dev,
				    dev_fwnode(&simone_keys_device.dev),
				    simone_key_left_props);
	platform_device_register(&simone_keys_device);
	...
}

Thanks for clarifying. I missed this last part where you feed the
properties to the device.

So looks fine by me :)