Extend sysfs to trigger an internal time-stamp event.
The trigger function can be used from an application to trigger an
internal time-stamp event.
Signed-off-by: Markus Burri <markus.burri@xxxxxx>
---
.../ABI/testing/sysfs-class-rtc-tamper | 7 ++++
drivers/rtc/rtc-rv8803.c | 33 +++++++++++++++++++
2 files changed, 40 insertions(+)
diff --git a/Documentation/ABI/testing/sysfs-class-rtc-tamper b/Documentation/ABI/testing/sysfs-class-rtc-tamper
index f035d0fa5..2fd6578a6 100644
--- a/Documentation/ABI/testing/sysfs-class-rtc-tamper
+++ b/Documentation/ABI/testing/sysfs-class-rtc-tamper
@@ -18,4 +18,11 @@ Description: (RO) Attribute to read the stored timestamps form buffer FIFO.
- "1234.567 EVIN1=1" for a trigger from EVIN1 changed from low to high
- "1234.567 EVIN1=0 EVIN2=1 for a simultaneous trigger of EVIN1 changed to low and
EVIN2 changed to high.
+ - "1234.567 CMD=0" for a internal trigger
+What: /sys/class/rtc/rtcX/tamper/trigger
+Date: January 2025
+KernelVersion: 6.13
+Contact: Markus Burri <markus.burri@xxxxxx>
+Description: (WO) Attribute to trigger an internal timestamp event
+ Write a '1' to trigger an internal event and store a timestamp.
diff --git a/drivers/rtc/rtc-rv8803.c b/drivers/rtc/rtc-rv8803.c
index 764e654c2..ca3a19162 100644
--- a/drivers/rtc/rtc-rv8803.c
+++ b/drivers/rtc/rtc-rv8803.c
@@ -904,12 +904,45 @@ static ssize_t read_show(struct device *dev, struct device_attribute *attr, char
return offset;
}
+static ssize_t trigger_store(struct device *dev, struct device_attribute *attr, const char *buf,
+ size_t count)
+{
+ struct rv8803_data *rv8803 = dev_get_drvdata(dev->parent);
+ struct i2c_client *client = rv8803->client;
+ int ret;
+ unsigned long tmo;
+
+ guard(mutex)(&rv8803->flags_lock);
+
+ /* CMDTRGEN */
+ ret = rv8803_write_reg(client, RX8901_WRCMD_CFG, BIT(0));
+ if (ret < 0)
+ return ret;
+ ret = rv8803_write_reg(client, RX8901_WRCMD_TRG, 0xFF);
+ if (ret < 0)
+ return ret;
+
+ tmo = jiffies + msecs_to_jiffies(100); /* timeout 100ms */
+ do {
+ usleep_range(10, 2000);
+ ret = rv8803_read_reg(client, RX8901_WRCMD_TRG);
+ if (ret < 0)
+ return ret;
+ if (time_after(jiffies, tmo))
+ return -EBUSY;
+ } while (ret);
+
+ return count;
+}
+
static DEVICE_ATTR_WO(enable);
static DEVICE_ATTR_RO(read);
+static DEVICE_ATTR_WO(trigger);
static struct attribute *rv8803_rtc_event_attrs[] = {
&dev_attr_enable.attr,
&dev_attr_read.attr,
+ &dev_attr_trigger.attr,
NULL
};
--
2.39.5
