2b1c6b21b5
As usual these patches were extracted and rebased from the raspberry pi repo: https://github.com/raspberrypi/linux/tree/rpi-4.4.y Also adds support for Raspberry Pi Compute Module 3 (untested). Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
58 lines
1.8 KiB
Diff
58 lines
1.8 KiB
Diff
From dab463aa0dbd5ac45403dade2723046eba214359 Mon Sep 17 00:00:00 2001
|
|
From: Nicolas Boullis <nboullis@debian.org>
|
|
Date: Sun, 10 Apr 2016 13:23:05 +0200
|
|
Subject: [PATCH] rtc: ds1307: ensure that any pending alarm is cleared before
|
|
a new alarm is enabled
|
|
MIME-Version: 1.0
|
|
Content-Type: text/plain; charset=UTF-8
|
|
Content-Transfer-Encoding: 8bit
|
|
|
|
If a previously-set alarm was disabled and then triggered, it may still
|
|
be pending when a new alarm is configured.
|
|
|
|
Then, if the alarm is enabled before the pending alarm is cleared, then
|
|
an interrupt is immediately raised.
|
|
|
|
Unfortunately, when the alarm is cleared and enabled during the same I²C
|
|
block write, the chip (at least the DS1339 I have) considers that the
|
|
alarm is enabled before it is cleared, and raises an interrupt.
|
|
|
|
This patch ensures that the pending alarm is cleared before the alarm is
|
|
enabled.
|
|
|
|
Signed-off-by: Nicolas Boullis <nboullis@debian.org>
|
|
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
|
|
---
|
|
drivers/rtc/rtc-ds1307.c | 13 ++++++++-----
|
|
1 file changed, 8 insertions(+), 5 deletions(-)
|
|
|
|
--- a/drivers/rtc/rtc-ds1307.c
|
|
+++ b/drivers/rtc/rtc-ds1307.c
|
|
@@ -540,12 +540,8 @@ static int ds1337_set_alarm(struct devic
|
|
buf[5] = 0;
|
|
buf[6] = 0;
|
|
|
|
- /* optionally enable ALARM1 */
|
|
+ /* disable alarms */
|
|
buf[7] = control & ~(DS1337_BIT_A1IE | DS1337_BIT_A2IE);
|
|
- if (t->enabled) {
|
|
- dev_dbg(dev, "alarm IRQ armed\n");
|
|
- buf[7] |= DS1337_BIT_A1IE; /* only ALARM1 is used */
|
|
- }
|
|
buf[8] = status & ~(DS1337_BIT_A1I | DS1337_BIT_A2I);
|
|
|
|
ret = ds1307->write_block_data(client,
|
|
@@ -555,6 +551,13 @@ static int ds1337_set_alarm(struct devic
|
|
return ret;
|
|
}
|
|
|
|
+ /* optionally enable ALARM1 */
|
|
+ if (t->enabled) {
|
|
+ dev_dbg(dev, "alarm IRQ armed\n");
|
|
+ buf[7] |= DS1337_BIT_A1IE; /* only ALARM1 is used */
|
|
+ i2c_smbus_write_byte_data(client, DS1337_REG_CONTROL, buf[7]);
|
|
+ }
|
|
+
|
|
return 0;
|
|
}
|
|
|