From mboxrd@z Thu Jan 1 00:00:00 1970 From: w.sang@pengutronix.de (Wolfram Sang) Date: Tue, 10 Aug 2010 15:40:55 +0200 Subject: [rtc-linux] [PATCH 1/2] rtc: rtc-lpc32xx: Introduce RTC driver for the LPC32XX SoC In-Reply-To: <20100810120055.GD11268@pengutronix.de> References: <1281370650-29520-1-git-send-email-wellsk40@gmail.com> <1281370650-29520-2-git-send-email-wellsk40@gmail.com> <20100810102507.GB4268@pengutronix.de> <20100810120055.GD11268@pengutronix.de> Message-ID: <20100810134055.GC4268@pengutronix.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Tue, Aug 10, 2010 at 02:00:55PM +0200, Uwe Kleine-K?nig wrote: > Hi Wolfram, > > > > + retval = request_irq(rtc->irq, lpc32xx_rtc_alarm_interrupt, > > > + IRQF_DISABLED, "rtcalarm", rtc); > > > + if (retval < 0) { > > > + dev_err(&pdev->dev, "Can't request interrupt\n"); > > > + goto err_free_irq; > > > + } > > > > I saw that a number of rtc-drivers register their irq after they > > register the device. I wonder if this is OK here? Couldn't it happen > > that after rtc_device_register() there is a preemption and another > > process could set the alarm? Then there is a race between interrupts > > already enabled and no handler available, no? > If you do it the other way around the irq might trigger and the handler > reports an irq for a device that doesn't exist yet. Well, I was assuming that you initially have all interrupts disabled... -- Pengutronix e.K. | Wolfram Sang | Industrial Linux Solutions | http://www.pengutronix.de/ | -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: application/pgp-signature Size: 198 bytes Desc: Digital signature URL: