[PATCH V7 1/3] ACPI: Retry IRQ conversion if it failed previously

From: Agustin Vega-Frias
Date: Sun Nov 13 2016 - 17:00:02 EST


This allows probe deferral to work properly when a dependent device
fails to get a valid IRQ because the IRQ domain was not registered
at the time the resources were added to the platform_device.

Signed-off-by: Agustin Vega-Frias <agustinv@xxxxxxxxxxxxxx>
---
drivers/acpi/resource.c | 59 +++++++++++++++++++++++++++++++++++++++++++++++++
drivers/base/platform.c | 9 +++++++-
include/linux/acpi.h | 7 ++++++
3 files changed, 74 insertions(+), 1 deletion(-)

diff --git a/drivers/acpi/resource.c b/drivers/acpi/resource.c
index 56241eb..4beda15 100644
--- a/drivers/acpi/resource.c
+++ b/drivers/acpi/resource.c
@@ -664,3 +664,62 @@ int acpi_dev_filter_resource_type(struct acpi_resource *ares,
return (type & types) ? 0 : 1;
}
EXPORT_SYMBOL_GPL(acpi_dev_filter_resource_type);
+
+struct acpi_irq_get_ctx {
+ unsigned int index;
+ struct resource *res;
+};
+
+static acpi_status acpi_irq_get_cb(struct acpi_resource *ares, void *context)
+{
+ struct acpi_irq_get_ctx *ctx = context;
+ struct acpi_resource_irq *irq;
+ struct acpi_resource_extended_irq *ext_irq;
+
+ switch (ares->type) {
+ case ACPI_RESOURCE_TYPE_IRQ:
+ irq = &ares->data.irq;
+ if (ctx->index < irq->interrupt_count) {
+ acpi_dev_resource_interrupt(ares, ctx->index, ctx->res);
+ return AE_CTRL_TERMINATE;
+ }
+ ctx->index -= irq->interrupt_count;
+ break;
+ case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
+ ext_irq = &ares->data.extended_irq;
+ if (ctx->index < ext_irq->interrupt_count) {
+ acpi_dev_resource_interrupt(ares, ctx->index, ctx->res);
+ return AE_CTRL_TERMINATE;
+ }
+ ctx->index -= ext_irq->interrupt_count;
+ break;
+ }
+
+ return AE_OK;
+}
+
+/**
+ * acpi_irq_get - Look for the ACPI IRQ resource with the given index and
+ * use it to initialize the given Linux IRQ resource.
+ * @handle ACPI device handle
+ * @index ACPI IRQ resource index to lookup
+ * @res Linux IRQ resource to initialize
+ *
+ * Return: 0 on success
+ * -EINVAL if an error occurs
+ * -EPROBE_DEFER if the IRQ lookup/conversion failed
+ */
+int acpi_irq_get(acpi_handle handle, unsigned int index, struct resource *res)
+{
+ struct acpi_irq_get_ctx ctx = { index, res };
+ acpi_status status;
+
+ status = acpi_walk_resources(handle, METHOD_NAME__CRS,
+ acpi_irq_get_cb, &ctx);
+ if (ACPI_FAILURE(status))
+ return -EINVAL;
+ if (res->flags & IORESOURCE_DISABLED)
+ return -EPROBE_DEFER;
+ return 0;
+}
+EXPORT_SYMBOL_GPL(acpi_irq_get);
diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index c4af003..61423d2 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -102,6 +102,14 @@ int platform_get_irq(struct platform_device *dev, unsigned int num)
}

r = platform_get_resource(dev, IORESOURCE_IRQ, num);
+ if (r && r->flags & IORESOURCE_DISABLED && ACPI_COMPANION(&dev->dev)) {
+ int ret;
+
+ ret = acpi_irq_get(ACPI_HANDLE(&dev->dev), num, r);
+ if (ret)
+ return ret;
+ }
+
/*
* The resources may pass trigger flags to the irqs that need
* to be set up. It so happens that the trigger flags for
@@ -1450,4 +1458,3 @@ void __init early_platform_cleanup(void)
memset(&pd->dev.devres_head, 0, sizeof(pd->dev.devres_head));
}
}
-
diff --git a/include/linux/acpi.h b/include/linux/acpi.h
index 689a8b9..325bdb9 100644
--- a/include/linux/acpi.h
+++ b/include/linux/acpi.h
@@ -406,6 +406,7 @@ bool acpi_dev_resource_ext_address_space(struct acpi_resource *ares,
unsigned int acpi_dev_get_irq_type(int triggering, int polarity);
bool acpi_dev_resource_interrupt(struct acpi_resource *ares, int index,
struct resource *res);
+int acpi_irq_get(acpi_handle handle, unsigned int index, struct resource *res);

void acpi_dev_free_resource_list(struct list_head *list);
int acpi_dev_get_resources(struct acpi_device *adev, struct list_head *list,
@@ -763,6 +764,12 @@ static inline int acpi_reconfig_notifier_unregister(struct notifier_block *nb)
return -EINVAL;
}

+static inline int acpi_irq_get(acpi_handle handle, unsigned int index,
+ struct resource *res)
+{
+ return -EINVAL;
+}
+
#endif /* !CONFIG_ACPI */

#ifdef CONFIG_ACPI_HOTPLUG_IOAPIC
--
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