1 files changed, 74 insertions, 2 deletions

diff --git a/drivers/misc/pvpanic/pvpanic.c b/drivers/misc/pvpanic/pvpanic.c
index 049a12006348..305b367e0ce3 100644
--- a/drivers/misc/pvpanic/pvpanic.c
+++ b/drivers/misc/pvpanic/pvpanic.c
@@ -7,6 +7,7 @@
  *  Copyright (C) 2021 Oracle.
  */
 
+#include <linux/device.h>
 #include <linux/io.h>
 #include <linux/kernel.h>
 #include <linux/kexec.h>
@@ -26,6 +27,13 @@ MODULE_AUTHOR("Mihai Carabas <mihai.carabas@oracle.com>");
 MODULE_DESCRIPTION("pvpanic device driver");
 MODULE_LICENSE("GPL");
 
+struct pvpanic_instance {
+	void __iomem *base;
+	unsigned int capability;
+	unsigned int events;
+	struct list_head list;
+};
+
 static struct list_head pvpanic_list;
 static spinlock_t pvpanic_lock;
 
@@ -81,11 +89,75 @@ static void pvpanic_remove(void *param)
 	spin_unlock(&pvpanic_lock);
 }
 
-int devm_pvpanic_probe(struct device *dev, struct pvpanic_instance *pi)
+static ssize_t capability_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct pvpanic_instance *pi = dev_get_drvdata(dev);
+
+	return sysfs_emit(buf, "%x\n", pi->capability);
+}
+static DEVICE_ATTR_RO(capability);
+
+static ssize_t events_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct pvpanic_instance *pi = dev_get_drvdata(dev);
+
+	return sysfs_emit(buf, "%x\n", pi->events);
+}
+
+static ssize_t events_store(struct device *dev, struct device_attribute *attr,
+			    const char *buf, size_t count)
+{
+	struct pvpanic_instance *pi = dev_get_drvdata(dev);
+	unsigned int tmp;
+	int err;
+
+	err = kstrtouint(buf, 16, &tmp);
+	if (err)
+		return err;
+
+	if ((tmp & pi->capability) != tmp)
+		return -EINVAL;
+
+	pi->events = tmp;
+
+	return count;
+}
+static DEVICE_ATTR_RW(events);
+
+static struct attribute *pvpanic_dev_attrs[] = {
+	&dev_attr_capability.attr,
+	&dev_attr_events.attr,
+	NULL
+};
+
+static const struct attribute_group pvpanic_dev_group = {
+	.attrs = pvpanic_dev_attrs,
+};
+
+const struct attribute_group *pvpanic_dev_groups[] = {
+	&pvpanic_dev_group,
+	NULL
+};
+EXPORT_SYMBOL_GPL(pvpanic_dev_groups);
+
+int devm_pvpanic_probe(struct device *dev, void __iomem *base)
 {
-	if (!pi || !pi->base)
+	struct pvpanic_instance *pi;
+
+	if (!base)
 		return -EINVAL;
 
+	pi = devm_kmalloc(dev, sizeof(*pi), GFP_KERNEL);
+	if (!pi)
+		return -ENOMEM;
+
+	pi->base = base;
+	pi->capability = PVPANIC_PANICKED | PVPANIC_CRASH_LOADED;
+
+	/* initlize capability by RDPT */
+	pi->capability &= ioread8(base);
+	pi->events = pi->capability;
+
 	spin_lock(&pvpanic_lock);
 	list_add(&pi->list, &pvpanic_list);
 	spin_unlock(&pvpanic_lock);