openwrt/target/linux/generic/patches-3.13/555-gluebi-sysfs-support.patch

Index: linux-3.13.2/drivers/mtd/ubi/gluebi.c
===================================================================
--- linux-3.13.2.orig/drivers/mtd/ubi/gluebi.c
+++ linux-3.13.2/drivers/mtd/ubi/gluebi.c
@@ -38,6 +38,7 @@
 #include <linux/mutex.h>
 #include <linux/mtd/ubi.h>
 #include <linux/mtd/mtd.h>
+#include <linux/export.h>
 #include "ubi-media.h"
 
 #define err_msg(fmt, ...)                                   \
@@ -66,6 +67,16 @@ struct gluebi_device {
 static LIST_HEAD(gluebi_devices);
 static DEFINE_MUTEX(devices_mutex);
 
+/* Device attribute handler for gluebi files in '/<sysfs>/class/mtd/mtdX' */
+static ssize_t gluebi_attribute_show(struct device *dev,
+	struct device_attribute *attr, char *buf);
+
+/* Device attributes corresponding to files in '/<sysfs>/class/mtd/mtdX' */
+static struct device_attribute attr_vol_gluebi_ubi_num =
+__ATTR(gluebi_ubi_num, S_IRUGO, gluebi_attribute_show, NULL);
+static struct device_attribute attr_vol_gluebi_vol_id =
+__ATTR(gluebi_vol_id, S_IRUGO, gluebi_attribute_show, NULL);
+
 /**
  * find_gluebi_nolock - find a gluebi device.
  * @ubi_num: UBI device number
@@ -288,6 +299,36 @@ out_err:
 }
 
 /**
+ * gluebi_attribute_show - "Show" method for gluebi files in sysfs.
+ */
+static ssize_t gluebi_attribute_show(struct device *dev,
+				  struct device_attribute *attr, char *buf)
+{
+	int ret;
+	struct mtd_info *mtd = container_of(dev, struct mtd_info, dev);
+	struct gluebi_device *gluebi;
+
+	gluebi_get_device(mtd);
+	gluebi = container_of(mtd, struct gluebi_device, mtd);
+
+	/* This really shouldn't happen */
+	if (!gluebi)
+		return -ENODEV;
+
+	if (attr == &attr_vol_gluebi_ubi_num) {
+		ret = sprintf(buf, "%u\n", gluebi->ubi_num);
+	} else if (attr == &attr_vol_gluebi_vol_id) {
+		ret = sprintf(buf, "%u\n", gluebi->vol_id);
+	} else {
+		/* This must be a bug */
+		ret = -EINVAL;
+	}
+
+	gluebi_put_device(mtd);
+	return ret;
+}
+
+/**
  * gluebi_create - create a gluebi device for an UBI volume.
  * @di: UBI device description object
  * @vi: UBI volume description object
@@ -355,6 +396,8 @@ static int gluebi_create(struct ubi_devi
 	mutex_lock(&devices_mutex);
 	list_add_tail(&gluebi->list, &gluebi_devices);
 	mutex_unlock(&devices_mutex);
+	device_create_file(&mtd->dev, &attr_vol_gluebi_ubi_num);
+	device_create_file(&mtd->dev, &attr_vol_gluebi_vol_id);
 	return 0;
 }
 
@@ -380,8 +423,11 @@ static int gluebi_remove(struct ubi_volu
 		err = -ENOENT;
 	} else if (gluebi->refcnt)
 		err = -EBUSY;
-	else
+	else {
+		device_remove_file(&gluebi->mtd.dev, &attr_vol_gluebi_ubi_num);
+		device_remove_file(&gluebi->mtd.dev, &attr_vol_gluebi_vol_id);
 		list_del(&gluebi->list);
+	}
 	mutex_unlock(&devices_mutex);
 	if (err)
 		return err;