3 files changed, 22 insertions, 1 deletions

diff --git a/include/linux/irq.h b/include/linux/irq.h
index 1d3577f30d4..5d876c9b3a3 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -28,6 +28,7 @@
 #include <asm/ptrace.h>
 #include <asm/irq_regs.h>
 
+struct seq_file;
 struct irq_desc;
 struct irq_data;
 typedef void (*irq_flow_handler_t)(unsigned int irq,
@@ -270,6 +271,7 @@ static inline bool irqd_can_move_in_process_context(struct irq_data *d)
  * @irq_set_wake:       enable/disable power-management wake-on of an IRQ
  * @irq_bus_lock:       function to lock access to slow bus (i2c) chips
  * @irq_bus_sync_unlock:function to sync and unlock slow bus (i2c) chips
+ * @irq_print_chip:     optional to print special chip info in show_interrupts
  * @flags:              chip specific flags
  *
  * @release:            release function solely used by UML
@@ -317,6 +319,8 @@ struct irq_chip {
         void            (*irq_bus_lock)(struct irq_data *data);
         void            (*irq_bus_sync_unlock)(struct irq_data *data);
 
+        void            (*irq_print_chip)(struct irq_data *data, struct seq_file *p);
+
         unsigned long   flags;
 
         /* Currently used only by UML, might disappear one day.*/
diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig
index 09bef82d74c..00f2c037267 100644
--- a/kernel/irq/Kconfig
+++ b/kernel/irq/Kconfig
@@ -31,6 +31,10 @@ config GENERIC_IRQ_PROBE
 config GENERIC_IRQ_SHOW
        bool
 
+# Print level/edge extra information
+config GENERIC_IRQ_SHOW_LEVEL
+       bool
+
 # Support for delayed migration from interrupt context
 config GENERIC_PENDING_IRQ
         bool
diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c
index 760248de109..626d092eed9 100644
--- a/kernel/irq/proc.c
+++ b/kernel/irq/proc.c
@@ -404,7 +404,20 @@ int show_interrupts(struct seq_file *p, void *v)
         seq_printf(p, "%*d: ", prec, i);
         for_each_online_cpu(j)
                 seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
-        seq_printf(p, " %8s", desc->irq_data.chip->name);
+
+        if (desc->irq_data.chip) {
+                if (desc->irq_data.chip->irq_print_chip)
+                        desc->irq_data.chip->irq_print_chip(&desc->irq_data, p);
+                else if (desc->irq_data.chip->name)
+                        seq_printf(p, " %8s", desc->irq_data.chip->name);
+                else
+                        seq_printf(p, " %8s", "-");
+        } else {
+                seq_printf(p, " %8s", "None");
+        }
+#ifdef CONFIG_GENIRC_IRQ_SHOW_LEVEL
+        seq_printf(p, " %-8s", irqd_is_level_type(&desc->irq_data) ? "Level" : "Edge");
+#endif
         if (desc->name)
                 seq_printf(p, "-%-8s", desc->name);