diff mbox

[3/4] rtc: pl031: avoid exposing alarm if no interrupt

Message ID E1dYKiK-0001kZ-6E@rmk-PC.armlinux.org.uk (mailing list archive)
State New, archived
Headers show

Commit Message

Russell King (Oracle) July 20, 2017, 11:18 p.m. UTC 
If the RTC has no interrupt, there is little point in exposing the RTC
alarm capabilities, as it can't be used as a wakeup source nor can it
deliver an event to userspace.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 drivers/rtc/rtc-pl031.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

Comments

Linus Walleij Aug. 2, 2017, 12:32 p.m. UTC | #1 
On Fri, Jul 21, 2017 at 1:18 AM, Russell King
<rmk+kernel@armlinux.org.uk> wrote:

> If the RTC has no interrupt, there is little point in exposing the RTC
> alarm capabilities, as it can't be used as a wakeup source nor can it
> deliver an event to userspace.
>
> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>

This makes all kind of sense.
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

Yours,
Linus Walleij
diff mbox

Patch

diff --git a/drivers/rtc/rtc-pl031.c b/drivers/rtc/rtc-pl031.c
index 5960fbd08b05..64c77ec1b4ea 100644
--- a/drivers/rtc/rtc-pl031.c
+++ b/drivers/rtc/rtc-pl031.c
@@ -329,12 +329,14 @@  static int pl031_probe(struct amba_device *adev, const struct amba_id *id)
 
 	ldata = devm_kzalloc(&adev->dev, sizeof(struct pl031_local),
 			     GFP_KERNEL);
-	if (!ldata) {
+	ops = devm_kmemdup(&adev->dev, &vendor->ops, sizeof(vendor->ops),
+			   GFP_KERNEL);
+	if (!ldata || !ops) {
 		ret = -ENOMEM;
 		goto out;
 	}
-	ldata->vendor = vendor;
 
+	ldata->vendor = vendor;
 	ldata->base = devm_ioremap(&adev->dev, adev->res.start,
 				   resource_size(&adev->res));
 	if (!ldata->base) {
@@ -372,6 +374,13 @@  static int pl031_probe(struct amba_device *adev, const struct amba_id *id)
 		}
 	}
 
+	if (!adev->irq[0]) {
+		/* When there's no interrupt, no point in exposing the alarm */
+		ops->read_alarm = NULL;
+		ops->set_alarm = NULL;
+		ops->alarm_irq_enable = NULL;
+	}
+
 	device_init_wakeup(&adev->dev, true);
 	ldata->rtc = rtc_device_register("pl031", &adev->dev, ops,
 					THIS_MODULE);