>From ebb5cb875363822e7c2dc17dae36f14dd4a0e71e Mon Sep 17 00:00:00 2001
From: Sandeep Kaushik <[email protected]>
Date: Fri, 18 Jul 2008 14:58:19 +0530
Subject: [PATCH] IRQ : bug fix in setup_irq
This patch is for bug fix in setup_irq function.
Error handling is added in setup_irq function. This is required in case if some
rchitecture dependent pins like gpio pins are requested as interrupt pin and
they are already occupied by other devices in some other modes, then setup_irq
must return error.
Signed-off-by: Sandeep Kaushik <[email protected]>
---
kernel/irq/manage.c | 24 +++++++++++++++++++-----
1 files changed, 19 insertions(+), 5 deletions(-)
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 1f31422..ca92f97 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -339,6 +339,7 @@ int setup_irq(unsigned int irq, struct irqaction *new)
desc->status |= IRQ_NO_BALANCING;
if (!shared) {
+ int trigger_type = 0;
irq_chip_set_defaults(desc->chip);
#if defined(CONFIG_IRQ_PER_CPU)
@@ -346,11 +347,22 @@ int setup_irq(unsigned int irq, struct irqaction *new)
desc->status |= IRQ_PER_CPU;
#endif
+ trigger_type = new->flags & IRQF_TRIGGER_MASK;
+
/* Setup the type (level, edge polarity) if configured: */
- if (new->flags & IRQF_TRIGGER_MASK) {
- if (desc->chip && desc->chip->set_type)
- desc->chip->set_type(irq,
- new->flags & IRQF_TRIGGER_MASK);
+ if (trigger_type) {
+ if (desc->chip && desc->chip->set_type) {
+ if ((desc->chip->set_type(irq, trigger_type))) {
+ /* Action handler gets freed but
+ * desc->action also needs to be
+ * set to NULL
+ */
+ *p = NULL;
+ spin_unlock_irqrestore(&desc->lock,
+ flags);
+ return -EBUSY;
+ }
+ }
else
/*
* IRQF_TRIGGER_* but the PIC does not support
@@ -571,8 +583,10 @@ int request_irq(unsigned int irq, irq_handler_t handler,
#endif
retval = setup_irq(irq, action);
- if (retval)
+ if (retval) {
+ printk(KERN_WARNING"Failed to allocate interrupt %d\n", retval);
kfree(action);
+ }
return retval;
}
--
1.5.6.GIT
On Fri, 18 Jul 2008, sasa sasa wrote:
> diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
> index 1f31422..ca92f97 100644
> --- a/kernel/irq/manage.c
> +++ b/kernel/irq/manage.c
> @@ -339,6 +339,7 @@ int setup_irq(unsigned int irq, struct irqaction *new)
> desc->status |= IRQ_NO_BALANCING;
>
> if (!shared) {
> + int trigger_type = 0;
No need to initialize to zero.
> irq_chip_set_defaults(desc->chip);
>
> #if defined(CONFIG_IRQ_PER_CPU)
> @@ -346,11 +347,22 @@ int setup_irq(unsigned int irq, struct irqaction *new)
> desc->status |= IRQ_PER_CPU;
> #endif
>
> + trigger_type = new->flags & IRQF_TRIGGER_MASK;
> +
> /* Setup the type (level, edge polarity) if configured: */
> - if (new->flags & IRQF_TRIGGER_MASK) {
> - if (desc->chip && desc->chip->set_type)
> - desc->chip->set_type(irq,
> - new->flags & IRQF_TRIGGER_MASK);
> + if (trigger_type) {
> + if (desc->chip && desc->chip->set_type) {
> + if ((desc->chip->set_type(irq, trigger_type))) {
> + /* Action handler gets freed but
> + * desc->action also needs to be
> + * set to NULL
> + */
That's not desc->action. That's the end of the desc->action list
> + *p = NULL;
Can we have a printk here, which tells us what went wrong ?
> + spin_unlock_irqrestore(&desc->lock,
> + flags);
> + return -EBUSY;
Please use the already existing error exit via "goto ..." instead
> + }
> + }
> else
> /*
> * IRQF_TRIGGER_* but the PIC does not support
> @@ -571,8 +583,10 @@ int request_irq(unsigned int irq, irq_handler_t handler,
> #endif
>
> retval = setup_irq(irq, action);
> - if (retval)
> + if (retval) {
> + printk(KERN_WARNING"Failed to allocate interrupt %d\n", retval);
> kfree(action);
We dont want to know that the setup function returned -EBUSY. We
rather want to have a printk in the path above.
Thanks,
tglx