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Abdurrahman HussainandAndi Shyti
3279986bfe
Convert the device-tree parsing path to the generic fwnode/device
property accessors so the driver can be probed on ACPI and swnode
platforms as well as OF. The helper is renamed from
i2c_mux_reg_probe_dt() to i2c_mux_reg_probe_fw() to reflect that.
Accessor translation:
of_parse_phandle("i2c-parent") +
of_find_i2c_adapter_by_node() -> fwnode_find_reference() +
i2c_find_adapter_by_fwnode()
of_get_child_count() -> device_get_child_node_count()
of_property_read_bool() -> device_property_read_bool()
for_each_child_of_node() -> device_for_each_child_node()
of_property_read_u32("reg") on ACPI device nodes:
acpi_get_local_address()
everything else (OF, swnode,
ACPI data nodes):
fwnode_property_read_u32()
of_property_read_u32("idle-state") -> device_property_read_u32()
The child-node branch uses is_acpi_device_node() rather than
is_acpi_node(): the latter also matches ACPI data nodes (the
_DSD hierarchical-property children used by PRP0001-style
firmware), which have no ACPI handle and would make
acpi_get_local_address() fall back to evaluating _ADR against the
root namespace and return -ENODATA. Routing data nodes through
fwnode_property_read_u32() instead lets them resolve the "reg"
property the same way OF and swnode children do.
Behavioural preservations (deliberate, to avoid regressing existing
users):
- The three-way endian fallback is kept verbatim: an explicit
"little-endian" property wins, then "big-endian", and otherwise
the host's compile-time byte order. device_is_big_endian() is
not used here because it ignores "little-endian" and introduces
"native-endian" semantics, which would diverge from the binding.
- The "if (!mux->data.reg)" guard around
devm_platform_get_and_ioremap_resource() in probe() is kept.
drivers/platform/mellanox/mlx-platform.c registers i2c-mux-reg
platform_devices with no memory resource and supplies a
pre-set .reg / .reg_size through struct
i2c_mux_reg_platform_data; without the guard those
registrations would fail in probe().
- The "if (!mux->data.reg)" ioremap block (and the paired
reg_size validation that depends on it) is hoisted above
i2c_get_adapter(mux->data.parent), so the fwnode path
preserves master's ordering of "ioremap before parent-adapter
get". For platdata users the validation runs from a slightly
earlier position, but mux->data.reg_size is already set from
platdata by then, so the order is functionally neutral.
The OF-only of_address_to_resource() translation in the old
probe_dt() is dropped because the same address is available from
the platform_device resource table on OF as well as ACPI, and the
existing fallback in probe() ioremaps it.
Acked-by: Peter Rosin <peda@lysator.liu.se>
Signed-off-by: Abdurrahman Hussain <abdurrahman@nexthop.ai>
Assisted-by: Claude-Code:claude-opus-4-7
Assisted-by: sashiko:gemini-3.1-pro-preview
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Andi Shyti <andi.shyti@kernel.org>