[PATCH 03/12] rtc: omap: fix class-device registration

Johan Hovold johan at kernel.org
Thu Oct 9 12:06:25 PDT 2014


Make sure not to register the class device until after it has been
configured and interrupt handlers registered at probe.

Currently, the device is not fully configured (e.g. 24-hour mode) when
the class device is registered, something which involves driver
callbacks for example to read the current time.

This reordering also prevents user space from enabling an alarm before
an interrupt handler has been registered.

Note that the interrupts are now registered using the platform-device
rather than class-device name.

Signed-off-by: Johan Hovold <johan at kernel.org>
---
 drivers/rtc/rtc-omap.c | 32 +++++++++++++++++---------------
 1 file changed, 17 insertions(+), 15 deletions(-)

diff --git a/drivers/rtc/rtc-omap.c b/drivers/rtc/rtc-omap.c
index 828cb9983cc2..2eca141e784e 100644
--- a/drivers/rtc/rtc-omap.c
+++ b/drivers/rtc/rtc-omap.c
@@ -147,8 +147,9 @@ static void rtc_wait_not_busy(void)
 	/* now we have ~15 usec to read/write various registers */
 }
 
-static irqreturn_t rtc_irq(int irq, void *rtc)
+static irqreturn_t rtc_irq(int irq, void *dev_id)
 {
+	struct rtc_device	*rtc = platform_get_drvdata(dev_id);
 	unsigned long		events = 0;
 	u8			irq_data;
 
@@ -164,7 +165,8 @@ static irqreturn_t rtc_irq(int irq, void *rtc)
 	if (irq_data & OMAP_RTC_STATUS_1S_EVENT)
 		events |= RTC_IRQF | RTC_UF;
 
-	rtc_update_irq(rtc, 1, events);
+	if (rtc)
+		rtc_update_irq(rtc, 1, events);
 
 	return IRQ_HANDLED;
 }
@@ -416,17 +418,6 @@ static int __init omap_rtc_probe(struct platform_device *pdev)
 		rtc_writel(KICK1_VALUE, OMAP_RTC_KICK1_REG);
 	}
 
-	device_init_wakeup(&pdev->dev, true);
-
-	rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
-			&omap_rtc_ops, THIS_MODULE);
-	if (IS_ERR(rtc)) {
-		pr_debug("%s: can't register RTC device, err %ld\n",
-			pdev->name, PTR_ERR(rtc));
-		goto fail0;
-	}
-	platform_set_drvdata(pdev, rtc);
-
 	/* clear pending irqs, and set 1/second periodic,
 	 * which we'll use instead of update irqs
 	 */
@@ -450,14 +441,14 @@ static int __init omap_rtc_probe(struct platform_device *pdev)
 
 	/* handle periodic and alarm irqs */
 	if (devm_request_irq(&pdev->dev, omap_rtc_timer, rtc_irq, 0,
-			dev_name(&rtc->dev), rtc)) {
+			dev_name(&pdev->dev), pdev)) {
 		pr_debug("%s: RTC timer interrupt IRQ%d already claimed\n",
 			pdev->name, omap_rtc_timer);
 		goto fail0;
 	}
 	if ((omap_rtc_timer != omap_rtc_alarm) &&
 		(devm_request_irq(&pdev->dev, omap_rtc_alarm, rtc_irq, 0,
-			dev_name(&rtc->dev), rtc))) {
+			dev_name(&pdev->dev), pdev))) {
 		pr_debug("%s: RTC alarm interrupt IRQ%d already claimed\n",
 			pdev->name, omap_rtc_alarm);
 		goto fail0;
@@ -492,6 +483,17 @@ static int __init omap_rtc_probe(struct platform_device *pdev)
 	if (reg != new_ctrl)
 		rtc_write(new_ctrl, OMAP_RTC_CTRL_REG);
 
+	device_init_wakeup(&pdev->dev, true);
+
+	rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
+			&omap_rtc_ops, THIS_MODULE);
+	if (IS_ERR(rtc)) {
+		pr_debug("%s: can't register RTC device, err %ld\n",
+			pdev->name, PTR_ERR(rtc));
+		goto fail0;
+	}
+	platform_set_drvdata(pdev, rtc);
+
 	return 0;
 
 fail0:
-- 
2.0.4




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