mei: export fw status registers through sysfs

The interface is for applications that monitor
the fw health.

We use device_create_with_groups interface
to register attribute with the mei class device

Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/misc/mei/main.c b/drivers/misc/mei/main.c
index beedc91f03a631cc9fd5902d7cd14e840edcef33..ae56ba6ca0e3615758953259c4223efab7322613 100644 (file)
--- a/drivers/misc/mei/main.c
+++ b/drivers/misc/mei/main.c
@@ -631,6 +631,44 @@ out:
        return mask;
 }
 
+/**
+ * fw_status_show - mei device attribute show method
+ *
+ * @device: device pointer
+ * @attr: attribute pointer
+ * @buf:  char out buffer
+ *
+ * Return: number of the bytes printed into buf or error
+ */
+static ssize_t fw_status_show(struct device *device,
+               struct device_attribute *attr, char *buf)
+{
+       struct mei_device *dev = dev_get_drvdata(device);
+       struct mei_fw_status fw_status;
+       int err, i;
+       ssize_t cnt = 0;
+
+       mutex_lock(&dev->device_lock);
+       err = mei_fw_status(dev, &fw_status);
+       mutex_unlock(&dev->device_lock);
+       if (err) {
+               dev_err(device, "read fw_status error = %d\n", err);
+               return err;
+       }
+
+       for (i = 0; i < fw_status.count; i++)
+               cnt += scnprintf(buf + cnt, PAGE_SIZE - cnt, "%08X\n",
+                               fw_status.status[i]);
+       return cnt;
+}
+static DEVICE_ATTR_RO(fw_status);
+
+static struct attribute *mei_attrs[] = {
+       &dev_attr_fw_status.attr,
+       NULL
+};
+ATTRIBUTE_GROUPS(mei);
+
 /*
  * file operations structure will be used for mei char device.
  */
@@ -710,8 +748,9 @@ int mei_register(struct mei_device *dev, struct device *parent)
                goto err_dev_add;
        }
 
-       clsdev = device_create(mei_class, parent, devno,
-                        NULL, "mei%d", dev->minor);
+       clsdev = device_create_with_groups(mei_class, parent, devno,
+                                          dev, mei_groups,
+                                          "mei%d", dev->minor);
 
        if (IS_ERR(clsdev)) {
                dev_err(parent, "unable to create device %d:%d\n",