Re: [PATCH 5/9] coresight-tpdm: Add nodes to set trigger timestamp and type

[Suzuki K Poulose <suzuki.poulose@arm.com>]

On 08/09/2022 09:45, Tao Zhang wrote:
> The nodes are needed to set or show the trigger timestamp and
> trigger type. This change is to add these nodes to achieve these
> function.
> 
> Signed-off-by: Tao Zhang <quic_taozha@quicinc.com>
> ---
>   drivers/hwtracing/coresight/coresight-tpdm.c | 90 ++++++++++++++++++++++++++++
>   1 file changed, 90 insertions(+)
> 
> diff --git a/drivers/hwtracing/coresight/coresight-tpdm.c b/drivers/hwtracing/coresight/coresight-tpdm.c
> index 74cc653..fae9963 100644
> --- a/drivers/hwtracing/coresight/coresight-tpdm.c
> +++ b/drivers/hwtracing/coresight/coresight-tpdm.c
> @@ -232,8 +232,98 @@ static struct attribute_group tpdm_attr_grp = {
>   	.attrs = tpdm_attrs,
>   };
>   
> +static ssize_t dsb_trig_type_show(struct device *dev,
> +				     struct device_attribute *attr,
> +				     char *buf)
> +{
> +	struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
> +
> +	if (!(drvdata->datasets & TPDM_PIDR0_DS_DSB))
> +		return -EPERM;
> +
> +	return scnprintf(buf, PAGE_SIZE, "%u\n",
> +			 (unsigned int)drvdata->dsb->trig_type);
> +}
> +
> +/*
> + * value 0: set trigger type as enablement
> + * value 1: set trigger type as disablement
> + */
> +static ssize_t dsb_trig_type_store(struct device *dev,
> +				      struct device_attribute *attr,
> +				      const char *buf,
> +				      size_t size)
> +{
> +	struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
> +	unsigned long val;
> +
> +	if ((kstrtoul(buf, 16, &val)) || val < 0 || val > 1)
> +		return -EINVAL;
> +	if (!(drvdata->datasets & TPDM_PIDR0_DS_DSB))
> +		return -EPERM;
> +
> +	spin_lock(&drvdata->spinlock);
> +	if (val)
> +		drvdata->dsb->trig_type = true;
> +	else
> +		drvdata->dsb->trig_type = false;
> +	spin_unlock(&drvdata->spinlock);
> +	return size;
> +}
> +static DEVICE_ATTR_RW(dsb_trig_type);
> +
> +static ssize_t dsb_trig_ts_show(struct device *dev,
> +				     struct device_attribute *attr,
> +				     char *buf)
> +{
> +	struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
> +
> +	if (!(drvdata->datasets & TPDM_PIDR0_DS_DSB))
> +		return -EPERM;
> +
> +	return scnprintf(buf, PAGE_SIZE, "%u\n",
> +			 (unsigned int)drvdata->dsb->trig_ts);
> +}
> +
> +/*
> + * value 0: set trigger timestamp as enablement
> + * value 1: set trigger timestamp as disablement
> + */
> +static ssize_t dsb_trig_ts_store(struct device *dev,
> +				      struct device_attribute *attr,
> +				      const char *buf,
> +				      size_t size)
> +{
> +	struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
> +	unsigned long val;
> +
> +	if ((kstrtoul(buf, 16, &val)) || val < 0 || val > 1)
> +		return -EINVAL;
> +	if (!(drvdata->datasets & TPDM_PIDR0_DS_DSB))
> +		return -EPERM;
> +
> +	spin_lock(&drvdata->spinlock);
> +	if (val)
> +		drvdata->dsb->trig_ts = true;
> +	else
> +		drvdata->dsb->trig_ts = false;
> +	spin_unlock(&drvdata->spinlock);
> +	return size;
> +}
> +static DEVICE_ATTR_RW(dsb_trig_ts);
> +static struct attribute *tpdm_dsb_attrs[] = {
> +	&dev_attr_dsb_trig_ts.attr,
> +	&dev_attr_dsb_trig_type.attr,
> +	NULL,
> +};
> +
> +static struct attribute_group tpdm_dsb_attr_grp = {
> +	.attrs = tpdm_dsb_attrs,
> +};
> +

Please could we hide the "DSB" related knobs, if the
the Data sets are missing using is_visible() hook ?

Suzuki