Re: [PATCH v5 9/9] power: sequencing: pcie-m2: Create serdev device for WCN7850 bluetooth

[Bartosz Golaszewski]

On Tue, 24 Feb 2026 06:30:55 +0100, Manivannan Sadhasivam via B4 Relay
<devnull+manivannan.sadhasivam.oss.qualcomm.com@xxxxxxxxxx> said:
> From: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxxxxxxxx>
>
> For supporting bluetooth over the non-discoverable UART interface of
> WCN7850, create the serdev device after enumerating the PCIe interface.
> This is mandatory since the device ID is only known after the PCIe
> enumeration and the ID is used for creating the serdev device.
>
> Since by default there is no OF or ACPI node for the created serdev,
> create a dynamic OF 'bluetooth' node with the 'compatible' property and
> attach it to the serdev device. This will allow the serdev device to bind
> to the existing bluetooth driver.
>
> Tested-by: Hans de Goede <johannes.goede@xxxxxxxxxxxxxxxx> # ThinkPad T14s gen6 (arm64)
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxxxxxxxx>
> ---
>

[snip]

> -static void pwrseq_pcie_m2_free_regulators(void *data)
> +static void pwrseq_pcie_m2_free_resources(void *data)
>  {
>  	struct pwrseq_pcie_m2_ctx *ctx = data;
>
> +	serdev_device_remove(ctx->serdev);
> +	bus_unregister_notifier(&pci_bus_type, &ctx->nb);
> +	of_changeset_revert(ctx->ocs);
> +	of_changeset_destroy(ctx->ocs);
>  	regulator_bulk_free(ctx->num_vregs, ctx->regs);
>  }
>
> +static int pwrseq_m2_pcie_create_bt_node(struct pwrseq_pcie_m2_ctx *ctx,
> +					struct device_node *parent)
> +{
> +	struct device *dev = ctx->dev;
> +	struct device_node *np;
> +	int ret;
> +
> +	ctx->ocs = devm_kzalloc(dev, sizeof(*ctx->ocs), GFP_KERNEL);
> +	if (!ctx->ocs)
> +		return -ENOMEM;
> +
> +	of_changeset_init(ctx->ocs);
> +
> +	np = of_changeset_create_node(ctx->ocs, parent, "bluetooth");
> +	if (!np) {
> +		dev_err(dev, "Failed to create bluetooth node\n");
> +		ret = -ENODEV;
> +		goto err_destroy_changeset;
> +	}
> +
> +	ret = of_changeset_add_prop_string(ctx->ocs, np, "compatible", "qcom,wcn7850-bt");
> +	if (ret) {
> +		dev_err(dev, "Failed to add bluetooth compatible: %d\n", ret);
> +		goto err_destroy_changeset;
> +	}
> +
> +	ret = of_changeset_apply(ctx->ocs);
> +	if (ret) {
> +		dev_err(dev, "Failed to apply changeset: %d\n", ret);
> +		goto err_destroy_changeset;
> +	}
> +
> +	ret = device_add_of_node(&ctx->serdev->dev, np);
> +	if (ret) {
> +		dev_err(dev, "Failed to add OF node: %d\n", ret);
> +		goto err_revert_changeset;
> +	}
> +
> +	return 0;
> +
> +err_revert_changeset:
> +	of_changeset_revert(ctx->ocs);
> +err_destroy_changeset:
> +	of_changeset_destroy(ctx->ocs);
> +

I would prefer pwrseq_pcie_m2_free_resources() to be split into separate
devm actions, otherwise it's not much different from simply having the
.remove() callback. With a split like that you'd avoid having these labels
here.

Otherwise looks good.

Bart