From 0d5daa938c94b8b9183e9b257a88dc0929d59409 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Mon, 20 Oct 2025 13:29:21 +0100 Subject: [PATCH] platform: Add firmware-agnostic irq and affinity retrieval interface Expand platform_get_irq_optional() to also return an affinity if available, renaming it to platform_get_irq_affinity() in the process. platform_get_irq_optional() is preserved with its current semantics by calling into the new helper with a NULL affinity pointer. Signed-off-by: Marc Zyngier Signed-off-by: Thomas Gleixner Tested-by: Will Deacon Reviewed-by: Jonathan Cameron Link: https://patch.msgid.link/20251020122944.3074811-5-maz@kernel.org --- drivers/base/platform.c | 71 ++++++++++++++++++++++++++------- include/linux/platform_device.h | 2 + 2 files changed, 58 insertions(+), 15 deletions(-) diff --git a/drivers/base/platform.c b/drivers/base/platform.c index 09450349cf323..b45d41b018ca6 100644 --- a/drivers/base/platform.c +++ b/drivers/base/platform.c @@ -150,25 +150,37 @@ devm_platform_ioremap_resource_byname(struct platform_device *pdev, EXPORT_SYMBOL_GPL(devm_platform_ioremap_resource_byname); #endif /* CONFIG_HAS_IOMEM */ +static const struct cpumask *get_irq_affinity(struct platform_device *dev, + unsigned int num) +{ + const struct cpumask *mask = NULL; +#ifndef CONFIG_SPARC + struct fwnode_handle *fwnode = dev_fwnode(&dev->dev); + + if (is_of_node(fwnode)) + mask = of_irq_get_affinity(to_of_node(fwnode), num); + else if (is_acpi_device_node(fwnode)) + mask = acpi_irq_get_affinity(ACPI_HANDLE_FWNODE(fwnode), num); +#endif + + return mask ?: cpu_possible_mask; +} + /** - * platform_get_irq_optional - get an optional IRQ for a device - * @dev: platform device - * @num: IRQ number index + * platform_get_irq_affinity - get an optional IRQ and its affinity for a device + * @dev: platform device + * @num: interrupt number index + * @affinity: optional cpumask pointer to get the affinity of a per-cpu interrupt * - * Gets an IRQ for a platform device. Device drivers should check the return - * value for errors so as to not pass a negative integer value to the - * request_irq() APIs. This is the same as platform_get_irq(), except that it - * does not print an error message if an IRQ can not be obtained. - * - * For example:: - * - * int irq = platform_get_irq_optional(pdev, 0); - * if (irq < 0) - * return irq; + * Gets an interupt for a platform device. Device drivers should check the + * return value for errors so as to not pass a negative integer value to + * the request_irq() APIs. Optional affinity information is provided in the + * affinity pointer if available, and NULL otherwise. * - * Return: non-zero IRQ number on success, negative error number on failure. + * Return: non-zero interrupt number on success, negative error number on failure. */ -int platform_get_irq_optional(struct platform_device *dev, unsigned int num) +int platform_get_irq_affinity(struct platform_device *dev, unsigned int num, + const struct cpumask **affinity) { int ret; #ifdef CONFIG_SPARC @@ -236,8 +248,37 @@ out_not_found: out: if (WARN(!ret, "0 is an invalid IRQ number\n")) return -EINVAL; + + if (ret > 0 && affinity) + *affinity = get_irq_affinity(dev, num); + return ret; } +EXPORT_SYMBOL_GPL(platform_get_irq_affinity); + +/** + * platform_get_irq_optional - get an optional interrupt for a device + * @dev: platform device + * @num: interrupt number index + * + * Gets an interrupt for a platform device. Device drivers should check the + * return value for errors so as to not pass a negative integer value to + * the request_irq() APIs. This is the same as platform_get_irq(), except + * that it does not print an error message if an interrupt can not be + * obtained. + * + * For example:: + * + * int irq = platform_get_irq_optional(pdev, 0); + * if (irq < 0) + * return irq; + * + * Return: non-zero interrupt number on success, negative error number on failure. + */ +int platform_get_irq_optional(struct platform_device *dev, unsigned int num) +{ + return platform_get_irq_affinity(dev, num, NULL); +} EXPORT_SYMBOL_GPL(platform_get_irq_optional); /** diff --git a/include/linux/platform_device.h b/include/linux/platform_device.h index 074754c23d330..ad66333ce85ce 100644 --- a/include/linux/platform_device.h +++ b/include/linux/platform_device.h @@ -102,6 +102,8 @@ devm_platform_ioremap_resource_byname(struct platform_device *pdev, extern int platform_get_irq(struct platform_device *, unsigned int); extern int platform_get_irq_optional(struct platform_device *, unsigned int); +extern int platform_get_irq_affinity(struct platform_device *, unsigned int, + const struct cpumask **); extern int platform_irq_count(struct platform_device *); extern int devm_platform_get_irqs_affinity(struct platform_device *dev, struct irq_affinity *affd, -- 2.47.3