On Tue, 04 Aug 2026, Alexandre MINETTE via B4 Relay wrote:
> From: Alexandre MINETTE <[email protected]>
>
> PM8921 reports the USB ID pin through interrupt 49 of its interrupt
> controller. Unlike PM8941, this path has no separate addressable misc
> block to represent as a devicetree child node.
>
> Register a child platform device for the existing Qualcomm USB extcon
> driver after creating the PMIC IRQ domain. Pass the USB ID interrupt as
> a named resource and reuse the PM8921 firmware node, allowing consumers
> to reference the PMIC node directly as their extcon provider.
>
> Unregister the child device and dispose of the IRQ mapping when the
> PMIC is removed or probing fails.
>
> Signed-off-by: Alexandre MINETTE <[email protected]>
> ---
> drivers/mfd/qcom-pm8xxx.c | 78
> +++++++++++++++++++++++++++++++++++++++++++++--
> 1 file changed, 76 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/mfd/qcom-pm8xxx.c b/drivers/mfd/qcom-pm8xxx.c
> index 0cf374c015ce..884fc99a1488 100644
> --- dangerously/mfd/qcom-pm8xxx.c
> +++ b/drivers/mfd/qcom-pm8xxx.c
> @@ -7,6 +7,7 @@
>
> #include <linux/kernel.h>
> #include <linux/interrupt.h>
> +#include <linux/ioport.h>
> #include <linux/irqchip/chained_irq.h>
> #include <linux/irq.h>
> #include <linux/irqdomain.h>
> @@ -64,12 +65,15 @@
>
> struct pm_irq_data {
> int num_irqs;
> + int usb_id_irq;
> struct irq_chip *irq_chip;
> irq_handler_t irq_handler;
> };
>
> struct pm_irq_chip {
> struct regmap *regmap;
> + struct platform_device *usb_extcon;
> + unsigned int usb_id_irq;
> spinlock_t pm_irq_lock;
> struct irq_domain *irqdomain;
> unsigned int num_blocks;
> @@ -492,6 +496,13 @@ static const struct pm_irq_data pm8xxx_data = {
> .irq_handler = pm8xxx_irq_handler,
> };
>
> +static const struct pm_irq_data pm8921_data = {
> + .num_irqs = PM8XXX_NR_IRQS,
> + .usb_id_irq = 49,
Magic numbers should be defined.
> + .irq_chip = &pm8xxx_irq_chip,
> + .irq_handler = pm8xxx_irq_handler,
> +};
> +
> static const struct pm_irq_data pm8821_data = {
> .num_irqs = PM8821_NR_IRQS,
> .irq_chip = &pm8821_irq_chip,
> @@ -501,11 +512,60 @@ static const struct pm_irq_data pm8821_data = {
> static const struct of_device_id pm8xxx_id_table[] = {
> { .compatible = "qcom,pm8058", .data = &pm8xxx_data},
> { .compatible = "qcom,pm8821", .data = &pm8821_data},
> - { .compatible = "qcom,pm8921", .data = &pm8xxx_data},
> + { .compatible = "qcom,pm8921", .data = &pm8921_data},
> { }
> };
> MODULE_DEVICE_TABLE(of, pm8xxx_id_table);
>
> +static int pm8xxx_add_usb_extcon(struct platform_device *pdev,
> + struct pm_irq_chip *chip,
> + unsigned int hwirq)
> +{
> + struct irq_fwspec fwspec = {
> + .fwnode = dev_fwnode(&pdev->dev),
> + .param_count = 2,
> + .param = { hwirq, IRQ_TYPE_EDGE_BOTH },
> + };
> + struct platform_device_info pdevinfo = {
> + .parent = &pdev->dev,
> + .fwnode = dev_fwnode(&pdev->dev),
> + .of_node_reused = true,
> + .name = "qcom-pm8xxx-usb-id",
> + .id = PLATFORM_DEVID_NONE,
> + };
> + struct resource resource;
> +
> + chip->usb_id_irq = irq_create_fwspec_mapping(&fwspec);
> + if (!chip->usb_id_irq)
> + return -ENXIO;
> +
> + resource = DEFINE_RES_IRQ_NAMED(chip->usb_id_irq, "usb_id");
> + pdevinfo.res = &resource;
> + pdevinfo.num_res = 1;
> +
> + chip->usb_extcon = platform_device_register_full(&pdevinfo);
Why aren't you using the MFD API for this?
> + if (IS_ERR(chip->usb_extcon)) {
> + int ret = PTR_ERR(chip->usb_extcon);
> +
> + chip->usb_extcon = NULL;
> + irq_dispose_mapping(chip->usb_id_irq);
> + chip->usb_id_irq = 0;
> +
> + return ret;
> + }
> +
> + return 0;
> +}
> +
> +static void pm8xxx_remove_usb_extcon(struct pm_irq_chip *chip)
> +{
> + if (chip->usb_extcon)
> + platform_device_unregister(chip->usb_extcon);
> +
> + if (chip->usb_id_irq)
> + irq_dispose_mapping(chip->usb_id_irq);
> +}
Why not devm_*
> static int pm8xxx_probe(struct platform_device *pdev)
> {
> const struct pm_irq_data *data;
> @@ -570,9 +630,22 @@ static int pm8xxx_probe(struct platform_device *pdev)
>
> irq_set_irq_wake(irq, 1);
>
> + if (data->usb_id_irq) {
> + rc = pm8xxx_add_usb_extcon(pdev, chip, data->usb_id_irq);
> + if (rc)
> + goto err_domain;
> + }
> +
> rc = of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev);
> if (rc)
> - irq_domain_remove(chip->irqdomain);
> + goto err_extcon;
> +
> + return 0;
> +
> +err_extcon:
> + pm8xxx_remove_usb_extcon(chip);
> +err_domain:
> + irq_domain_remove(chip->irqdomain);
>
> return rc;
> }
> @@ -582,6 +655,7 @@ static void pm8xxx_remove(struct platform_device *pdev)
> struct pm_irq_chip *chip = platform_get_drvdata(pdev);
>
> of_platform_depopulate(&pdev->dev);
> + pm8xxx_remove_usb_extcon(chip);
> irq_domain_remove(chip->irqdomain);
> }
>
>
> --
> 2.43.0
>
>
--
Lee Jones
