[MIPS] IRQ cleanups

This is a big irq cleanup patch.

* Use set_irq_chip() to register irq_chip.
* Initialize .mask, .unmask, .mask_ack field.  Functions for these
  method are already exist in most case.
* Do not initialize .startup, .shutdown, .enable, .disable fields if
  default routines provided by irq_chip_set_defaults() were suitable.
* Remove redundant irq_desc initializations.
* Remove unnecessary local_irq_save/local_irq_restore, spin_lock.

With this cleanup, it would be easy to switch to slightly lightwait
irq flow handlers (handle_level_irq(), etc.) instead of __do_IRQ().

Though whole this patch is quite large, changes in each irq_chip are
not quite simple.  Please review and test on your platform.  Thanks.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 5 insertions, 27 deletions

diff --git a/arch/mips/jmr3927/rbhma3100/irq.c b/arch/mips/jmr3927/rbhma3100/irq.c
index de4a238c28be..3da49c5aaf49 100644
--- a/arch/mips/jmr3927/rbhma3100/irq.c
+++ b/arch/mips/jmr3927/rbhma3100/irq.c
@@ -90,17 +90,6 @@ static unsigned char irc_level[TX3927_NUM_IR] = {
 static void jmr3927_irq_disable(unsigned int irq_nr);
 static void jmr3927_irq_enable(unsigned int irq_nr);
 
-static DEFINE_SPINLOCK(jmr3927_irq_lock);
-
-static unsigned int jmr3927_irq_startup(unsigned int irq)
-{
-        jmr3927_irq_enable(irq);
-
-        return 0;
-}
-
-#define jmr3927_irq_shutdown    jmr3927_irq_disable
-
 static void jmr3927_irq_ack(unsigned int irq)
 {
         if (irq == JMR3927_IRQ_IRC_TMR0)
@@ -118,9 +107,7 @@ static void jmr3927_irq_end(unsigned int irq)
 static void jmr3927_irq_disable(unsigned int irq_nr)
 {
         struct tb_irq_space* sp;
-        unsigned long flags;
 
-        spin_lock_irqsave(&jmr3927_irq_lock, flags);
         for (sp = tb_irq_spaces; sp; sp = sp->next) {
                 if (sp->start_irqno <= irq_nr &&
                     irq_nr < sp->start_irqno + sp->nr_irqs) {
@@ -130,15 +117,12 @@ static void jmr3927_irq_disable(unsigned int irq_nr)
                         break;
                 }
         }
-        spin_unlock_irqrestore(&jmr3927_irq_lock, flags);
 }
 
 static void jmr3927_irq_enable(unsigned int irq_nr)
 {
         struct tb_irq_space* sp;
-        unsigned long flags;
 
-        spin_lock_irqsave(&jmr3927_irq_lock, flags);
         for (sp = tb_irq_spaces; sp; sp = sp->next) {
                 if (sp->start_irqno <= irq_nr &&
                     irq_nr < sp->start_irqno + sp->nr_irqs) {
@@ -148,7 +132,6 @@ static void jmr3927_irq_enable(unsigned int irq_nr)
                         break;
                 }
         }
-        spin_unlock_irqrestore(&jmr3927_irq_lock, flags);
 }
 
 /*
@@ -457,11 +440,10 @@ void __init arch_init_irq(void)
 
 static struct irq_chip jmr3927_irq_controller = {
         .typename = "jmr3927_irq",
-        .startup = jmr3927_irq_startup,
-        .shutdown = jmr3927_irq_shutdown,
-        .enable = jmr3927_irq_enable,
-        .disable = jmr3927_irq_disable,
         .ack = jmr3927_irq_ack,
+        .mask = jmr3927_irq_disable,
+        .mask_ack = jmr3927_irq_ack,
+        .unmask = jmr3927_irq_enable,
         .end = jmr3927_irq_end,
 };
 
@@ -469,12 +451,8 @@ void jmr3927_irq_init(u32 irq_base)
 {
         u32 i;
 
-        for (i= irq_base; i< irq_base + JMR3927_NR_IRQ_IRC + JMR3927_NR_IRQ_IOC; i++) {
-                irq_desc[i].status = IRQ_DISABLED;
-                irq_desc[i].action = NULL;
-                irq_desc[i].depth = 1;
-                irq_desc[i].chip = &jmr3927_irq_controller;
-        }
+        for (i= irq_base; i< irq_base + JMR3927_NR_IRQ_IRC + JMR3927_NR_IRQ_IOC; i++)
+                set_irq_chip(i, &jmr3927_irq_controller);
 
         jmr3927_irq_base = irq_base;
 }