[Patch Part2 v5 04/31] genirq: Introduce irq_chip.irq_compose_msi_msg() to support stacked irqchip

Jiang Liu
2014-11-06T14:18:24Z

Add callback irq_compose_msi_msg to struct irq_chip, which will be used
to support stacked irqchip.

Signed-off-by: Jiang Liu <jiang.liu@linux.intel.com>
---
include/linux/irq.h | 5 +++++
kernel/irq/chip.c | 17 +++++++++++++++++
2 files changed, 22 insertions(+)

diff --git a/include/linux/irq.h b/include/linux/irq.h
index 0adcbbbf2e87..536b7fc6c8f4 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -29,6 +29,7 @@ struct seq_file;
struct module;
struct irq_desc;
struct irq_data;
+struct msi_msg;
typedef void (*irq_flow_handler_t)(unsigned int irq,
struct irq_desc *desc);
typedef void (*irq_preflow_handler_t)(struct irq_data *data);
@@ -320,6 +321,7 @@ static inline irq_hw_number_t irqd_to_hwirq(struct irq_data *d)
* any other callback related to this irq
* @irq_release_resources: optional to release resources acquired with
* irq_request_resources
+ * @irq_compose_msi_msg: optional to compose message content for MSI
* @flags: chip specific flags
*/
struct irq_chip {
@@ -356,6 +358,8 @@ struct irq_chip {
int (*irq_request_resources)(struct irq_data *data);
void (*irq_release_resources)(struct irq_data *data);

+ void (*irq_compose_msi_msg)(struct irq_data *data, struct msi_msg *msg);
+
unsigned long flags;
};

@@ -443,6 +447,7 @@ extern void handle_percpu_devid_irq(unsigned int irq, struct irq_desc *desc);
extern void handle_bad_irq(unsigned int irq, struct irq_desc *desc);
extern void handle_nested_irq(unsigned int irq);

+extern int irq_chip_compose_msi_msg(struct irq_data *data, struct msi_msg *msg);
#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
extern void irq_chip_ack_parent(struct irq_data *data);
extern int irq_chip_retrigger_hierarchy(struct irq_data *data);
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index 12f3e72449eb..8f362db17a8a 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -867,3 +867,20 @@ int irq_chip_retrigger_hierarchy(struct irq_data *data)
return -ENOSYS;
}
#endif
+
+int irq_chip_compose_msi_msg(struct irq_data *data, struct msi_msg *msg)
+{
+ struct irq_data *pos = NULL;
+
+#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
+ for (; data; data = data->parent_data)
+#endif
+ if (data->chip && data->chip->irq_compose_msi_msg)
+ pos = data;
+ if (!pos)
+ return -ENOSYS;
+
+ pos->chip->irq_compose_msi_msg(pos, msg);
+
+ return 0;
+}
--
1.7.10.4