genirq: irq_chip->startup() usage in setup_irq and set_irq_chained handler

This patch clarifies usage of irq_chip->startup() callback:

1. The "if (startup) startup(); else enabled();" code in setup_irq()
   is unnecessary, as startup() falls back to enabled() via
   default callbacks, set by irq_chip_set_defaults().

2. When using set_irq_chained_handler() the startup() was never called,
   which is not good at all... Fixed. And again - when startup() is not
   defined the call will fall back to enable() than to unmask() via
   default callbacks.

Signed-off-by: Pawel Moll <pawel.moll@st.com>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

2 files changed, 2 insertions, 5 deletions

diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index 964964baefa2..240c64d59267 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -587,7 +587,7 @@ __set_irq_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
                 desc->status &= ~IRQ_DISABLED;
                 desc->status |= IRQ_NOREQUEST | IRQ_NOPROBE;
                 desc->depth = 0;
-                desc->chip->unmask(irq);
+                desc->chip->startup(irq);
         }
         spin_unlock_irqrestore(&desc->lock, flags);
 }
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index ae1b684e048c..9aa3e7b81389 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -397,10 +397,7 @@ int setup_irq(unsigned int irq, struct irqaction *new)
                 if (!(desc->status & IRQ_NOAUTOEN)) {
                         desc->depth = 0;
                         desc->status &= ~IRQ_DISABLED;
-                        if (desc->chip->startup)
-                                desc->chip->startup(irq);
-                        else
-                                desc->chip->enable(irq);
+                        desc->chip->startup(irq);
                 } else
                         /* Undo nested disables: */
                         desc->depth = 1;