Re: [PATCH] genirq: irq_chip->startup() usage in setup_irq and set_irq_chained handler

Ingo Molnar
2008-09-06T18:37:43Z

* Pawel MOLL <pawel.moll@st.com> wrote:

> 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>

applied the commit below to tip/genirq - thanks Pawel.

Ingo

------------->
>From 7e6e178ab1548c8d894a77593e757acf4510b8ba Mon Sep 17 00:00:00 2001
From: Pawel MOLL <pawel.moll@st.com>
Date: Mon, 1 Sep 2008 10:12:11 +0100
Subject: [PATCH] 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>
---
kernel/irq/chip.c | 2 +-
kernel/irq/manage.c | 5 +----
2 files changed, 2 insertions(+), 5 deletions(-)

diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index 964964b..240c64d 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 ae1b684..9aa3e7b 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;