remoteproc: qcom: Add sysfs entry to detect device shutdown

This change adds a sysfs entry which indicates whether the device is being
shutdown to the qcom remoteproc drivers. This is going to be used in the
following patches.

Signed-off-by: Gokul krishna Krishnakumar <quic_gokukris@quicinc.com>

drivers/remoteproc/qcom_common.c

@@ -87,9 +87,32 @@ struct qcom_ssr_subsystem {
 	struct list_head list;
 };
 
+static struct kobject *sysfs_kobject;
+bool qcom_device_shutdown_in_progress;
+EXPORT_SYMBOL(qcom_device_shutdown_in_progress);
+
 static LIST_HEAD(qcom_ssr_subsystem_list);
 static DEFINE_MUTEX(qcom_ssr_subsys_lock);
 
+static const char * const ssr_timeout_msg = "srcu notifier chain for %s:%s taking too long";
+
+static ssize_t qcom_rproc_shutdown_request_store(struct kobject *kobj, struct kobj_attribute *attr,
+						 const char *buf, size_t count)
+{
+	bool val;
+	int ret;
+
+	ret = kstrtobool(buf, &val);
+	if (ret)
+		return ret;
+
+	qcom_device_shutdown_in_progress = val;
+	pr_info("qcom rproc: Device shutdown requested: %s\n", val ? "true" : "false");
+	return count;
+}
+static struct kobj_attribute shutdown_requested_attr = __ATTR(shutdown_in_progress, 0220, NULL,
+							  qcom_rproc_shutdown_request_store);
+
 static void qcom_minidump_cleanup(struct rproc *rproc)
 {
 	struct rproc_dump_segment *entry, *tmp;
@@ -505,5 +528,40 @@ void qcom_remove_ssr_subdev(struct rproc *rproc, struct qcom_rproc_ssr *ssr)
 }
 EXPORT_SYMBOL_GPL(qcom_remove_ssr_subdev);
 
+static int __init qcom_common_init(void)
+{
+	int ret = 0;
+
+	qcom_device_shutdown_in_progress = false;
+
+	sysfs_kobject = kobject_create_and_add("qcom_rproc", kernel_kobj);
+	if (!sysfs_kobject) {
+		pr_err("qcom rproc: failed to create sysfs kobject\n");
+		return -EINVAL;
+	}
+
+	ret = sysfs_create_file(sysfs_kobject, &shutdown_requested_attr.attr);
+	if (ret) {
+		pr_err("qcom rproc: failed to create sysfs file\n");
+		goto remove_kobject;
+	}
+
+	return 0;
+
+	sysfs_remove_file(sysfs_kobject, &shutdown_requested_attr.attr);
+remove_kobject:
+	kobject_put(sysfs_kobject);
+	return ret;
+
+}
+module_init(qcom_common_init);
+
+static void __exit qcom_common_exit(void)
+{
+	sysfs_remove_file(sysfs_kobject, &shutdown_requested_attr.attr);
+	kobject_put(sysfs_kobject);
+}
+module_exit(qcom_common_exit);
+
 MODULE_DESCRIPTION("Qualcomm Remoteproc helper driver");
 MODULE_LICENSE("GPL v2");

drivers/remoteproc/qcom_common.h

@@ -34,6 +34,7 @@ struct qcom_rproc_ssr {
 };
 
 void qcom_minidump(struct rproc *rproc, unsigned int minidump_id);
+extern bool qcom_device_shutdown_in_progress;
 
 void qcom_add_glink_subdev(struct rproc *rproc, struct qcom_rproc_glink *glink,
 			   const char *ssr_name);