=
> +static int sdw_amd_scan_controller(struct device *dev)
> +{
> + struct acp63_dev_data *acp_data;
> + struct fwnode_handle *link;
> + char name[32];
> + u32 sdw_manager_bitmap;
> + u8 count = 0;
> + u32 acp_sdw_power_mode = 0;
> + int index;
> + int ret;
> +
> + acp_data = dev_get_drvdata(dev);
> + /*
> + * Current implementation is based on MIPI DisCo 2.0 spec.
> + * Found controller, find links supported.
> + */
> + ret = fwnode_property_read_u32_array((acp_data->sdw_fw_node), "mipi-sdw-manager-list",
> + &sdw_manager_bitmap, 1);
> +
> + if (ret) {
> + dev_err(dev, "Failed to read mipi-sdw-manager-list: %d\n", ret);
> + return -EINVAL;
> + }
> + count = hweight32(sdw_manager_bitmap);
> + /* Check count is within bounds */
> + if (count > AMD_SDW_MAX_MANAGERS) {
> + dev_err(dev, "Manager count %d exceeds max %d\n", count, AMD_SDW_MAX_MANAGERS);
> + return -EINVAL;
> + }
nit-pick: the count is not enough, you should also check that only bits
0 and 1 are set in mipi-sdw-manager-list...
> +
> + if (!count) {
> + dev_dbg(dev, "No SoundWire Managers detected\n");
> + return -EINVAL;
> + }
> + dev_dbg(dev, "ACPI reports %d SoundWire Manager devices\n", count);
> + acp_data->sdw_manager_count = count;
> + for (index = 0; index < count; index++) {
> + snprintf(name, sizeof(name), "mipi-sdw-link-%d-subproperties", index);
... otherwise this will be wrong.
> + link = fwnode_get_named_child_node(acp_data->sdw_fw_node, name);
> + if (!link) {
> + dev_err(dev, "Manager node %s not found\n", name);
> + return -EIO;
> + }
> +
> + ret = fwnode_property_read_u32(link, "amd-sdw-power-mode", &acp_sdw_power_mode);
> + if (ret)
> + return ret;
> + /*
> + * when SoundWire configuration is selected from acp pin config,
> + * based on manager instances count, acp init/de-init sequence should be
> + * executed as part of PM ops only when Bus reset is applied for the active
> + * SoundWire manager instances.
> + */
> + if (acp_sdw_power_mode != AMD_SDW_POWER_OFF_MODE) {
> + acp_data->acp_reset = false;
> + return 0;
> + }
> + }
> + return 0;
> +}
