genirq: Add chip suspend and resume callbacks

These callbacks are only called in the syscore suspend/resume code on
interrupt chips which have been registered via the generic irq chip
mechanism. Calling those callbacks per irq would be rather icky, but
with the generic irq chip mechanism we can call this per registered
chip.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-arm-kernel@lists.infradead.org

1 files changed, 93 insertions, 0 deletions

diff --git a/kernel/irq/generic-chip.c b/kernel/irq/generic-chip.c
index eb23e5924260..31a9db711906 100644
--- a/kernel/irq/generic-chip.c
+++ b/kernel/irq/generic-chip.c
@@ -8,9 +8,13 @@
 #include <linux/slab.h>
 #include <linux/interrupt.h>
 #include <linux/kernel_stat.h>
+#include <linux/syscore_ops.h>
 
 #include "internals.h"
 
+static LIST_HEAD(gc_list);
+static DEFINE_RAW_SPINLOCK(gc_lock);
+
 static inline struct irq_chip_regs *cur_regs(struct irq_data *d)
 {
         return &container_of(d->chip, struct irq_chip_type, chip)->regs;
@@ -219,6 +223,10 @@ void irq_setup_generic_chip(struct irq_chip_generic *gc, u32 msk,
         struct irq_chip_type *ct = gc->chip_types;
         unsigned int i;
 
+        raw_spin_lock(&gc_lock);
+        list_add_tail(&gc->list, &gc_list);
+        raw_spin_unlock(&gc_lock);
+
         /* Init mask cache ? */
         if (flags & IRQ_GC_INIT_MASK_CACHE)
                 gc->mask_cache = irq_reg_readl(gc->reg_base + ct->regs.mask);
@@ -259,3 +267,88 @@ int irq_setup_alt_chip(struct irq_data *d, unsigned int type)
         }
         return -EINVAL;
 }
+
+/**
+ * irq_remove_generic_chip - Remove a chip
+ * @gc:         Generic irq chip holding all data
+ * @msk:        Bitmask holding the irqs to initialize relative to gc->irq_base
+ * @clr:        IRQ_* bits to clear
+ * @set:        IRQ_* bits to set
+ *
+ * Remove up to 32 interrupts starting from gc->irq_base.
+ */
+void irq_remove_generic_chip(struct irq_chip_generic *gc, u32 msk,
+                             unsigned int clr, unsigned int set)
+{
+        unsigned int i = gc->irq_base;
+
+        raw_spin_lock(&gc_lock);
+        list_del(&gc->list);
+        raw_spin_unlock(&gc_lock);
+
+        for (; msk; msk >>= 1, i++) {
+                if (!msk & 0x01)
+                        continue;
+
+                /* Remove handler first. That will mask the irq line */
+                irq_set_handler(i, NULL);
+                irq_set_chip(i, &no_irq_chip);
+                irq_set_chip_data(i, NULL);
+                irq_modify_status(i, clr, set);
+        }
+}
+
+#ifdef CONFIG_PM
+static int irq_gc_suspend(void)
+{
+        struct irq_chip_generic *gc;
+
+        list_for_each_entry(gc, &gc_list, list) {
+                struct irq_chip_type *ct = gc->chip_types;
+
+                if (ct->chip.irq_suspend)
+                        ct->chip.irq_suspend(irq_get_irq_data(gc->irq_base));
+        }
+        return 0;
+}
+
+static void irq_gc_resume(void)
+{
+        struct irq_chip_generic *gc;
+
+        list_for_each_entry(gc, &gc_list, list) {
+                struct irq_chip_type *ct = gc->chip_types;
+
+                if (ct->chip.irq_resume)
+                        ct->chip.irq_resume(irq_get_irq_data(gc->irq_base));
+        }
+}
+#else
+#define irq_gc_suspend NULL
+#define irq_gc_resume NULL
+#endif
+
+static void irq_gc_shutdown(void)
+{
+        struct irq_chip_generic *gc;
+
+        list_for_each_entry(gc, &gc_list, list) {
+                struct irq_chip_type *ct = gc->chip_types;
+
+                if (ct->chip.irq_pm_shutdown)
+                        ct->chip.irq_pm_shutdown(irq_get_irq_data(gc->irq_base));
+        }
+}
+
+static struct syscore_ops irq_gc_syscore_ops = {
+        .suspend = irq_gc_suspend,
+        .resume = irq_gc_resume,
+        .shutdown = irq_gc_shutdown,
+};
+
+static int __init irq_gc_init_ops(void)
+{
+        register_syscore_ops(&irq_gc_syscore_ops);
+        return 0;
+}
+device_initcall(irq_gc_init_ops);