On Thu, Jan 16, 2025 at 02:15:31PM +0100, Markus Burri wrote:
> 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>
Reviewed-by: Manuel Traut <manuel.traut@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
>
