RE: [PATCH-V2 1/3] RTC:s35390a: Add Alarm interrupt support

From: Hiremath, Vaibhav
Date: Mon Aug 23 2010 - 00:59:40 EST


> -----Original Message-----
> From: Felipe Balbi [mailto:felipe.balbi@xxxxxxxxx]
> Sent: Saturday, August 21, 2010 7:36 PM
> To: Hiremath, Vaibhav
> Cc: linux-kernel@xxxxxxxxxxxxxxx; akpm@xxxxxxxxxxxxxxxxxxxx;
> byron.bbradley@xxxxxxxxx; linux-omap@xxxxxxxxxxxxxxx; Balbi Felipe (Nokia-
> MS/Helsinki)
> Subject: Re: [PATCH-V2 1/3] RTC:s35390a: Add Alarm interrupt support
>
> Hi,
>
> On Sat, Aug 21, 2010 at 02:30:27PM +0200, ext hvaibhav@xxxxxx wrote:
> >+static irqreturn_t s35390a_irq_thread(int irq, void *handle)
> >+{
> >+ char buf[1];
> >+ struct s35390a *s35390a = handle;
> >+ struct i2c_client *client = s35390a->client[0];
>
> don't you need some locking on the irq handler ? a mutex maybe ? Just
> wondering...
>
[Hiremath, Vaibhav] Yes definitely we do need locking here, I thought of adding locking mechanism in subsequent patch, does it makes sense?


> >@@ -261,15 +424,30 @@ static int s35390a_probe(struct i2c_client *client,
> > if (s35390a_get_datetime(client, &tm) < 0)
> > dev_warn(&client->dev, "clock needs to be set\n");
> >
> >+ if (client->irq >= 0) {
> >+ err = request_threaded_irq(client->irq, NULL,
> >+ s35390a_irq_thread,
> >+ IRQF_TRIGGER_LOW | IRQF_ONESHOT,
> >+ client->name, s35390a);
> >+ if (err) {
> >+ dev_err(&client->dev, "unable to request IRQ\n");
> >+ goto exit_dummy;
> >+ }
> >+ }
> >+
> > s35390a->rtc = rtc_device_register(s35390a_driver.driver.name,
> > &client->dev, &s35390a_rtc_ops, THIS_MODULE);
> >
> > if (IS_ERR(s35390a->rtc)) {
> > err = PTR_ERR(s35390a->rtc);
> >- goto exit_dummy;
> >+ goto exit_intr;
> > }
> >+
> > return 0;
> >
> >+exit_intr:
> >+ free_irq(client->irq, client);
>
> free_irq() won't behave correctly, I believe since you're passing
> different dev_id parameters. If you look at the implementation of
> free_irq() you'll see it uses dev_id to find the correct struct
> irqaction pointer.
>
[Hiremath, Vaibhav] Overlooked, my bad. Thanks for pointing this to me ,will fix.


Thanks,
Vaibhav
> --
> balbi
>
> DefectiveByDesign.org
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/