scsi: mpi3mr: Add shost related sysfs attributes

Add shost related sysfs attributes to display the controller's firmware
version, queue depth, number of requests, and number of reply queues. Also
add an attribute to set & get the logging_level.

Link: https://lore.kernel.org/r/20220517115310.13062-2-sreekanth.reddy@broadcom.com
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Sreekanth Reddy <sreekanth.reddy@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Author: sreekanthbrcm

drivers/scsi/mpi3mr/mpi3mr_app.c

@@ -1558,13 +1558,147 @@ void mpi3mr_bsg_init(struct mpi3mr_ioc *mrioc)
 	kfree(mrioc->bsg_dev);
 }
 
+/**
+ * version_fw_show - SysFS callback for firmware version read
+ * @dev: class device
+ * @attr: Device attributes
+ * @buf: Buffer to copy
+ *
+ * Return: sysfs_emit() return after copying firmware version
+ */
+static ssize_t
+version_fw_show(struct device *dev, struct device_attribute *attr,
+	char *buf)
+{
+	struct Scsi_Host *shost = class_to_shost(dev);
+	struct mpi3mr_ioc *mrioc = shost_priv(shost);
+	struct mpi3mr_compimg_ver *fwver = &mrioc->facts.fw_ver;
+
+	return sysfs_emit(buf, "%d.%d.%d.%d.%05d-%05d\n",
+	    fwver->gen_major, fwver->gen_minor, fwver->ph_major,
+	    fwver->ph_minor, fwver->cust_id, fwver->build_num);
+}
+static DEVICE_ATTR_RO(version_fw);
+
+/**
+ * fw_queue_depth_show - SysFS callback for firmware max cmds
+ * @dev: class device
+ * @attr: Device attributes
+ * @buf: Buffer to copy
+ *
+ * Return: sysfs_emit() return after copying firmware max commands
+ */
+static ssize_t
+fw_queue_depth_show(struct device *dev, struct device_attribute *attr,
+			char *buf)
+{
+	struct Scsi_Host *shost = class_to_shost(dev);
+	struct mpi3mr_ioc *mrioc = shost_priv(shost);
+
+	return sysfs_emit(buf, "%d\n", mrioc->facts.max_reqs);
+}
+static DEVICE_ATTR_RO(fw_queue_depth);
+
+/**
+ * op_req_q_count_show - SysFS callback for request queue count
+ * @dev: class device
+ * @attr: Device attributes
+ * @buf: Buffer to copy
+ *
+ * Return: sysfs_emit() return after copying request queue count
+ */
+static ssize_t
+op_req_q_count_show(struct device *dev, struct device_attribute *attr,
+			char *buf)
+{
+	struct Scsi_Host *shost = class_to_shost(dev);
+	struct mpi3mr_ioc *mrioc = shost_priv(shost);
+
+	return sysfs_emit(buf, "%d\n", mrioc->num_op_req_q);
+}
+static DEVICE_ATTR_RO(op_req_q_count);
+
+/**
+ * reply_queue_count_show - SysFS callback for reply queue count
+ * @dev: class device
+ * @attr: Device attributes
+ * @buf: Buffer to copy
+ *
+ * Return: sysfs_emit() return after copying reply queue count
+ */
+static ssize_t
+reply_queue_count_show(struct device *dev, struct device_attribute *attr,
+			char *buf)
+{
+	struct Scsi_Host *shost = class_to_shost(dev);
+	struct mpi3mr_ioc *mrioc = shost_priv(shost);
+
+	return sysfs_emit(buf, "%d\n", mrioc->num_op_reply_q);
+}
+
+static DEVICE_ATTR_RO(reply_queue_count);
+
+/**
+ * logging_level_show - Show controller debug level
+ * @dev: class device
+ * @attr: Device attributes
+ * @buf: Buffer to copy
+ *
+ * A sysfs 'read/write' shost attribute, to show the current
+ * debug log level used by the driver for the specific
+ * controller.
+ *
+ * Return: sysfs_emit() return
+ */
+static ssize_t
+logging_level_show(struct device *dev,
+	struct device_attribute *attr, char *buf)
+
+{
+	struct Scsi_Host *shost = class_to_shost(dev);
+	struct mpi3mr_ioc *mrioc = shost_priv(shost);
+
+	return sysfs_emit(buf, "%08xh\n", mrioc->logging_level);
+}
+
+/**
+ * logging_level_store- Change controller debug level
+ * @dev: class device
+ * @attr: Device attributes
+ * @buf: Buffer to copy
+ * @count: size of the buffer
+ *
+ * A sysfs 'read/write' shost attribute, to change the current
+ * debug log level used by the driver for the specific
+ * controller.
+ *
+ * Return: strlen() return
+ */
+static ssize_t
+logging_level_store(struct device *dev,
+	struct device_attribute *attr,
+	const char *buf, size_t count)
+{
+	struct Scsi_Host *shost = class_to_shost(dev);
+	struct mpi3mr_ioc *mrioc = shost_priv(shost);
+	int val = 0;
+
+	if (kstrtoint(buf, 0, &val) != 0)
+		return -EINVAL;
+
+	mrioc->logging_level = val;
+	ioc_info(mrioc, "logging_level=%08xh\n", mrioc->logging_level);
+	return strlen(buf);
+}
+static DEVICE_ATTR_RW(logging_level);
+
 /**
  * adapter_state_show - SysFS callback for adapter state show
  * @dev: class device
  * @attr: Device attributes
  * @buf: Buffer to copy
  *
- * Return: snprintf() return after copying adapter state
+ * Return: sysfs_emit() return after copying adapter state
  */
 static ssize_t
 adp_state_show(struct device *dev, struct device_attribute *attr,
@@ -1585,12 +1719,17 @@ adp_state_show(struct device *dev, struct device_attribute *attr,
 	else
 		adp_state = MPI3MR_BSG_ADPSTATE_OPERATIONAL;
 
-	return snprintf(buf, PAGE_SIZE, "%u\n", adp_state);
+	return sysfs_emit(buf, "%u\n", adp_state);
 }
 
 static DEVICE_ATTR_RO(adp_state);
 
 static struct attribute *mpi3mr_host_attrs[] = {
+	&dev_attr_version_fw.attr,
+	&dev_attr_fw_queue_depth.attr,
+	&dev_attr_op_req_q_count.attr,
+	&dev_attr_reply_queue_count.attr,
+	&dev_attr_logging_level.attr,
 	&dev_attr_adp_state.attr,
 	NULL,
 };