Commit 64ee3cf0 authored by Rob Herring (Arm)'s avatar Rob Herring (Arm)
Browse files

of/address: Rework bus matching to avoid warnings 



With warnings added for deprecated #address-cells/#size-cells handling,
the DT address handling code causes warnings when used on nodes with no
address. This happens frequently with calls to of_platform_populate() as
it is perfectly acceptable to have devices without a 'reg' property. The
desired behavior is to just silently return an error when retrieving an
address.

The warnings can be avoided by checking for "#address-cells" presence
first and checking for an address property before fetching
"#address-cells" and "#size-cells".

Reported-by: default avatarMarek Szyprowski <m.szyprowski@samsung.com>
Reported-by: default avatarSteven Price <steven.price@arm.com>
Tested-by: default avatarMarek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20241108193547.2647986-2-robh@kernel.org


Signed-off-by: default avatarRob Herring (Arm) <robh@kernel.org>
parent 045b14ca

drivers/of/address.c

+9 −5
Original line number Diff line number Diff line
@@ -333,7 +333,11 @@ static unsigned int of_bus_isa_get_flags(const __be32 *addr) 


static int of_bus_default_flags_match(struct device_node *np)

{

	return of_bus_n_addr_cells(np) == 3;

	/*

	 * Check for presence first since of_bus_n_addr_cells() will warn when

	 * walking parent nodes.

	 */

	return of_property_present(np, "#address-cells") && (of_bus_n_addr_cells(np) == 3);

}



/*
@@ -701,16 +705,16 @@ const __be32 *__of_get_address(struct device_node *dev, int index, int bar_no, 
	if (strcmp(bus->name, "pci") && (bar_no >= 0))

		return NULL;



	bus->count_cells(dev, &na, &ns);

	if (!OF_CHECK_ADDR_COUNT(na))

		return NULL;



	/* Get "reg" or "assigned-addresses" property */

	prop = of_get_property(dev, bus->addresses, &psize);

	if (prop == NULL)

		return NULL;

	psize /= 4;



	bus->count_cells(dev, &na, &ns);

	if (!OF_CHECK_ADDR_COUNT(na))

		return NULL;



	onesize = na + ns;

	for (i = 0; psize >= onesize; psize -= onesize, prop += onesize, i++) {

		u32 val = be32_to_cpu(prop[0]);