Thanks Rafael. This looks mostly good but I have a doubt on the error handling, see below. > +static int sdw_acpi_check_duplicate(struct acpi_device *adev, void *data) > +{ > + struct sdw_acpi_child_walk_data *cwd = data; > + struct sdw_bus *bus = cwd->bus; > + struct sdw_slave_id id; > + > + if (adev == cwd->adev) > + return 0; > + > + if (!find_slave(bus, adev, &id)) > + return 0; > + > + if (cwd->id.sdw_version != id.sdw_version || cwd->id.mfg_id != id.mfg_id || > + cwd->id.part_id != id.part_id || cwd->id.class_id != id.class_id) > + return 0; > + > + if (cwd->id.unique_id != id.unique_id) { > + dev_dbg(bus->dev, > + "Valid unique IDs 0x%x 0x%x for Slave mfg_id 0x%04x, part_id 0x%04x\n", > + cwd->id.unique_id, id.unique_id, cwd->id.mfg_id, > + cwd->id.part_id); > + cwd->ignore_unique_id = false; > + return 0; > + } > + > + dev_err(bus->dev, > + "Invalid unique IDs 0x%x 0x%x for Slave mfg_id 0x%04x, part_id 0x%04x\n", > + cwd->id.unique_id, id.unique_id, cwd->id.mfg_id, cwd->id.part_id); > + return -ENODEV; if this error happens, I would guess it's reported .... > +} > + > +static int sdw_acpi_find_one(struct acpi_device *adev, void *data) > +{ > + struct sdw_bus *bus = data; > + struct sdw_acpi_child_walk_data cwd = { > + .bus = bus, > + .adev = adev, > + .ignore_unique_id = true, > + }; > + int ret; > + > + if (!find_slave(bus, adev, &cwd.id)) > + return 0; > + > + /* Brute-force O(N^2) search for duplicates. */ > + ret = acpi_dev_for_each_child(ACPI_COMPANION(bus->dev), > + sdw_acpi_check_duplicate, &cwd); > + if (ret) > + return ret; ... here, but I don't see this being propagated further... > + > + if (cwd.ignore_unique_id) > + cwd.id.unique_id = SDW_IGNORED_UNIQUE_ID; > + > + /* Ignore errors and continue. */ > + sdw_slave_add(bus, &cwd.id, acpi_fwnode_handle(adev)); > + return 0; > +} > + > /* > * sdw_acpi_find_slaves() - Find Slave devices in Master ACPI node > * @bus: SDW bus instance > @@ -135,8 +200,7 @@ static bool find_slave(struct sdw_bus *b > */ > int sdw_acpi_find_slaves(struct sdw_bus *bus) > { > - struct acpi_device *adev, *parent; > - struct acpi_device *adev2, *parent2; > + struct acpi_device *parent; > > parent = ACPI_COMPANION(bus->dev); > if (!parent) { > @@ -144,52 +208,7 @@ int sdw_acpi_find_slaves(struct sdw_bus > return -ENODEV; > } > > - list_for_each_entry(adev, &parent->children, node) { > - struct sdw_slave_id id; > - struct sdw_slave_id id2; > - bool ignore_unique_id = true; > - > - if (!find_slave(bus, adev, &id)) > - continue; > - > - /* brute-force O(N^2) search for duplicates */ > - parent2 = parent; > - list_for_each_entry(adev2, &parent2->children, node) { > - > - if (adev == adev2) > - continue; > - > - if (!find_slave(bus, adev2, &id2)) > - continue; > - > - if (id.sdw_version != id2.sdw_version || > - id.mfg_id != id2.mfg_id || > - id.part_id != id2.part_id || > - id.class_id != id2.class_id) > - continue; > - > - if (id.unique_id != id2.unique_id) { > - dev_dbg(bus->dev, > - "Valid unique IDs 0x%x 0x%x for Slave mfg_id 0x%04x, part_id 0x%04x\n", > - id.unique_id, id2.unique_id, id.mfg_id, id.part_id); > - ignore_unique_id = false; > - } else { > - dev_err(bus->dev, > - "Invalid unique IDs 0x%x 0x%x for Slave mfg_id 0x%04x, part_id 0x%04x\n", > - id.unique_id, id2.unique_id, id.mfg_id, id.part_id); > - return -ENODEV; > - } > - } > - > - if (ignore_unique_id) > - id.unique_id = SDW_IGNORED_UNIQUE_ID; > - > - /* > - * don't error check for sdw_slave_add as we want to continue > - * adding Slaves > - */ > - sdw_slave_add(bus, &id, acpi_fwnode_handle(adev)); > - } > + acpi_dev_for_each_child(parent, sdw_acpi_find_one, bus); ... here? It looks like a change in the error handling flow where sdw_acpi_find_slaves() is now returning 0 (success) always? Shouldn't the return of sdw_acpi_find_one() be trapped, e.g. with return acpi_dev_for_each_child(parent, sdw_acpi_find_one, bus); > > return 0; > } > > >