genirq: Introduce irq_chip.irq_compose_msi_msg() to support stacked irqchip

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>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Grant Likely <grant.likely@linaro.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Yingjoe Chen <yingjoe.chen@mediatek.com>
Cc: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 5 insertions, 0 deletions

diff --git a/include/linux/irq.h b/include/linux/irq.h
index fad4bf6f15f6..d58e58935465 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);