coresight-tpdm: Add nodes to set trigger timestamp and type

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>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/1695882586-10306-8-git-send-email-quic_taozha@quicinc.com

Documentation/ABI/testing/sysfs-bus-coresight-devices-tpdm

@@ -21,3 +21,25 @@ Description:
 
 		Accepts only one value -  1.
 		1 : Reset the dataset of the tpdm
+
+What:		/sys/bus/coresight/devices/<tpdm-name>/dsb_trig_type
+Date:		March 2023
+KernelVersion	6.7
+Contact:	Jinlong Mao (QUIC) <quic_jinlmao@quicinc.com>, Tao Zhang (QUIC) <quic_taozha@quicinc.com>
+Description:
+		(RW) Set/Get the trigger type of the DSB for tpdm.
+
+		Accepts only one of the 2 values -  0 or 1.
+		0 : Set the DSB trigger type to false
+		1 : Set the DSB trigger type to true
+
+What:		/sys/bus/coresight/devices/<tpdm-name>/dsb_trig_ts
+Date:		March 2023
+KernelVersion	6.7
+Contact:	Jinlong Mao (QUIC) <quic_jinlmao@quicinc.com>, Tao Zhang (QUIC) <quic_taozha@quicinc.com>
+Description:
+		(RW) Set/Get the trigger timestamp of the DSB for tpdm.
+
+		Accepts only one of the 2 values -  0 or 1.
+		0 : Set the DSB trigger type to false
+		1 : Set the DSB trigger type to true

drivers/hwtracing/coresight/coresight-tpdm.c

@@ -25,6 +25,18 @@ static bool tpdm_has_dsb_dataset(struct tpdm_drvdata *drvdata)
 	return (drvdata->datasets & TPDM_PIDR0_DS_DSB);
 }
 
+static umode_t tpdm_dsb_is_visible(struct kobject *kobj,
+				   struct attribute *attr, int n)
+{
+	struct device *dev = kobj_to_dev(kobj);
+	struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
+
+	if (drvdata && tpdm_has_dsb_dataset(drvdata))
+		return attr->mode;
+
+	return 0;
+}
+
 static void tpdm_reset_datasets(struct tpdm_drvdata *drvdata)
 {
 	if (tpdm_has_dsb_dataset(drvdata)) {
@@ -232,8 +244,91 @@ 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);
+
+	return sysfs_emit(buf, "%u\n",
+			 (unsigned int)drvdata->dsb->trig_type);
+}
+
+/*
+ * Trigger type (boolean):
+ * false - Disable trigger type.
+ * true  - Enable trigger type.
+ */
+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, 0, &val)) || (val & ~1UL))
+		return -EINVAL;
+
+	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);
+
+	return sysfs_emit(buf, "%u\n",
+			 (unsigned int)drvdata->dsb->trig_ts);
+}
+
+/*
+ * Trigger timestamp (boolean):
+ * false - Disable trigger timestamp.
+ * true  - Enable trigger timestamp.
+ */
+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, 0, &val)) || (val & ~1UL))
+		return -EINVAL;
+
+	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,
+	.is_visible = tpdm_dsb_is_visible,
+};
+
 static const struct attribute_group *tpdm_attr_grps[] = {
 	&tpdm_attr_grp,
+	&tpdm_dsb_attr_grp,
 	NULL,
 };