net: iosm: uevent support

Report modem status via uevent.
Signed-off-by: M Chetan Kumar <m.chetan.kumar@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/wwan/iosm/iosm_ipc_uevent.c

+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2020-21 Intel Corporation.
+ */
+
+#include <linux/device.h>
+#include <linux/kobject.h>
+#include <linux/slab.h>
+
+#include "iosm_ipc_uevent.h"
+
+/* Update the uevent in work queue context */
+static void ipc_uevent_work(struct work_struct *data)
+{
+	struct ipc_uevent_info *info;
+	char *envp[2] = { NULL, NULL };
+
+	info = container_of(data, struct ipc_uevent_info, work);
+
+	envp[0] = info->uevent;
+
+	if (kobject_uevent_env(&info->dev->kobj, KOBJ_CHANGE, envp))
+		pr_err("uevent %s failed to sent", info->uevent);
+
+	kfree(info);
+}
+
+void ipc_uevent_send(struct device *dev, char *uevent)
+{
+	struct ipc_uevent_info *info = kzalloc(sizeof(*info), GFP_ATOMIC);
+
+	if (!info)
+		return;
+
+	/* Initialize the kernel work queue */
+	INIT_WORK(&info->work, ipc_uevent_work);
+
+	/* Store the device and event information */
+	info->dev = dev;
+	snprintf(info->uevent, MAX_UEVENT_LEN, "%s: %s", dev_name(dev), uevent);
+
+	/* Schedule uevent in process context using work queue */
+	schedule_work(&info->work);
+}

drivers/net/wwan/iosm/iosm_ipc_uevent.h

+/* SPDX-License-Identifier: GPL-2.0-only
+ *
+ * Copyright (C) 2020-21 Intel Corporation.
+ */
+
+#ifndef IOSM_IPC_UEVENT_H
+#define IOSM_IPC_UEVENT_H
+
+/* Baseband event strings */
+#define UEVENT_MDM_NOT_READY "MDM_NOT_READY"
+#define UEVENT_ROM_READY "ROM_READY"
+#define UEVENT_MDM_READY "MDM_READY"
+#define UEVENT_CRASH "CRASH"
+#define UEVENT_CD_READY "CD_READY"
+#define UEVENT_CD_READY_LINK_DOWN "CD_READY_LINK_DOWN"
+#define UEVENT_MDM_TIMEOUT "MDM_TIMEOUT"
+
+/* Maximum length of user events */
+#define MAX_UEVENT_LEN 64
+
+/**
+ * struct ipc_uevent_info - Uevent information structure.
+ * @dev:	Pointer to device structure
+ * @uevent:	Uevent information
+ * @work:	Uevent work struct
+ */
+struct ipc_uevent_info {
+	struct device *dev;
+	char uevent[MAX_UEVENT_LEN];
+	struct work_struct work;
+};
+
+/**
+ * ipc_uevent_send - Send modem event to user space.
+ * @dev:	Generic device pointer
+ * @uevent:	Uevent information
+ *
+ */
+void ipc_uevent_send(struct device *dev, char *uevent);
+
+#endif