UIO: Add name attributes for mappings and port regions

If a UIO device has several memory mappings, it can be difficult for userspace to find the right one. The situation becomes even worse if the UIO driver can handle different versions of a card that have different numbers of mappings. Benedikt Spranger has such cards and pointed this out to me. Thanks, Bene! To address this problem, this patch adds "name" sysfs attributes for each mapping. Userspace can use these to clearly identify each mapping. The name string is optional. If a driver doesn't set it, an empty string will be returned, so this patch won't break existing drivers. The same problem exists for port region information, so a "name" attribute is added there, too. Signed-off-by: Hans J. Koch <hjk@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

UIO: Add name attributes for mappings and port regions
If a UIO device has several memory mappings, it can be difficult for userspace to find the right one. The situation becomes even worse if the UIO driver can handle different versions of a card that have different numbers of mappings. Benedikt Spranger has such cards and pointed this out to me. Thanks, Bene! To address this problem, this patch adds "name" sysfs attributes for each mapping. Userspace can use these to clearly identify each mapping. The name string is optional. If a driver doesn't set it, an empty string will be returned, so this patch won't break existing drivers. The same problem exists for port region information, so a "name" attribute is added there, too. Signed-off-by: Hans J. Koch <hjk@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Hans J. Koch · Greg Kroah-Hartman
1 parent 57fee4a58f
Showing 3 changed files with 51 additions and 4 deletions Side-by-side Diff
Documentation/DocBook/uio-howto.tmpl
drivers/uio/uio.c
include/linux/uio_driver.h
@@ -42,6 +42,13 @@
  
 <revhistory>
 	<revision>
+	<revnumber>0.8</revnumber>
+	<date>2008-12-24</date>
+	<authorinitials>hjk</authorinitials>
+	<revremark>Added name attributes in mem and portio sysfs directories.
+		</revremark>
+	</revision>
+	<revision>
 	<revnumber>0.7</revnumber>
 	<date>2008-12-23</date>
 	<authorinitials>hjk</authorinitials>
  
@@ -303,12 +310,19 @@
 	appear if the size of the mapping is not 0.
 </para>
 <para>
-	Each <filename>mapX/</filename> directory contains two read-only files
-	that show start address and size of the memory:
+	Each <filename>mapX/</filename> directory contains four read-only files
+	that show attributes of the memory:
 </para>
 <itemizedlist>
 <listitem>
 	<para>
+	<filename>name</filename>: A string identifier for this mapping. This
+	is optional, the string can be empty. Drivers can set this to make it
+	easier for userspace to find the correct mapping.
+	</para>
+</listitem>
+<listitem>
+	<para>
 	<filename>addr</filename>: The address of memory that can be mapped.
 	</para>
 </listitem>
  
@@ -366,10 +380,17 @@
 	<filename>/sys/class/uio/uioX/portio/</filename>.
 </para>
 <para>
-	Each <filename>portX/</filename> directory contains three read-only
-	files that show start, size, and type of the port region:
+	Each <filename>portX/</filename> directory contains four read-only
+	files that show name, start, size, and type of the port region:
 </para>
 <itemizedlist>
+<listitem>
+	<para>
+	<filename>name</filename>: A string identifier for this port region.
+	The string is optional and can be empty. Drivers can set it to make it
+	easier for userspace to find a certain port region.
+	</para>
+</listitem>
 <listitem>
 	<para>
 	<filename>start</filename>: The first port of this region.
@@ -61,6 +61,14 @@
 };
 #define to_map(map) container_of(map, struct uio_map, kobj)
  
+static ssize_t map_name_show(struct uio_mem *mem, char *buf)
+{
+	if (unlikely(!mem->name))
+		mem->name = "";
+
+	return sprintf(buf, "%s\n", mem->name);
+}
+
 static ssize_t map_addr_show(struct uio_mem *mem, char *buf)
 {
 	return sprintf(buf, "0x%lx\n", mem->addr);
@@ -82,6 +90,8 @@
 	ssize_t (*store)(struct uio_mem *, const char *, size_t);
 };
  
+static struct map_sysfs_entry name_attribute =
+	__ATTR(name, S_IRUGO, map_name_show, NULL);
 static struct map_sysfs_entry addr_attribute =
 	__ATTR(addr, S_IRUGO, map_addr_show, NULL);
 static struct map_sysfs_entry size_attribute =
@@ -90,6 +100,7 @@
 	__ATTR(offset, S_IRUGO, map_offset_show, NULL);
  
 static struct attribute *attrs[] = {
+	&name_attribute.attr,
 	&addr_attribute.attr,
 	&size_attribute.attr,
 	&offset_attribute.attr,
@@ -133,6 +144,14 @@
 };
 #define to_portio(portio) container_of(portio, struct uio_portio, kobj)
  
+static ssize_t portio_name_show(struct uio_port *port, char *buf)
+{
+	if (unlikely(!port->name))
+		port->name = "";
+
+	return sprintf(buf, "%s\n", port->name);
+}
+
 static ssize_t portio_start_show(struct uio_port *port, char *buf)
 {
 	return sprintf(buf, "0x%lx\n", port->start);
@@ -159,6 +178,8 @@
 	ssize_t (*store)(struct uio_port *, const char *, size_t);
 };
  
+static struct portio_sysfs_entry portio_name_attribute =
+	__ATTR(name, S_IRUGO, portio_name_show, NULL);
 static struct portio_sysfs_entry portio_start_attribute =
 	__ATTR(start, S_IRUGO, portio_start_show, NULL);
 static struct portio_sysfs_entry portio_size_attribute =
@@ -167,6 +188,7 @@
 	__ATTR(porttype, S_IRUGO, portio_porttype_show, NULL);
  
 static struct attribute *portio_attrs[] = {
+	&portio_name_attribute.attr,
 	&portio_start_attribute.attr,
 	&portio_size_attribute.attr,
 	&portio_porttype_attribute.attr,
@@ -22,6 +22,7 @@
  
 /**
  * struct uio_mem - description of a UIO memory region
+ * @name:		name of the memory region for identification
  * @addr:		address of the device's memory
  * @size:		size of IO
  * @memtype:		type of memory addr points to
@@ -29,6 +30,7 @@
  * @map:		for use by the UIO core only.
  */
 struct uio_mem {
+	const char		*name;
 	unsigned long		addr;
 	unsigned long		size;
 	int			memtype;
  
@@ -42,12 +44,14 @@
  
 /**
  * struct uio_port - description of a UIO port region
+ * @name:		name of the port region for identification
  * @start:		start of port region
  * @size:		size of port region
  * @porttype:		type of port (see UIO_PORT_* below)
  * @portio:		for use by the UIO core only.
  */
 struct uio_port {
+	const char		*name;
 	unsigned long		start;
 	unsigned long		size;
 	int			porttype;
...	...	@@ -42,6 +42,13 @@
42	42
43	43	<revhistory>
44	44	<revision>
	45	+ <revnumber>0.8</revnumber>
	46	+ <date>2008-12-24</date>
	47	+ <authorinitials>hjk</authorinitials>
	48	+ <revremark>Added name attributes in mem and portio sysfs directories.
	49	+ </revremark>
	50	+ </revision>
	51	+ <revision>
45	52	<revnumber>0.7</revnumber>
46	53	<date>2008-12-23</date>
47	54	<authorinitials>hjk</authorinitials>
48	55
...	...	@@ -303,12 +310,19 @@
303	310	appear if the size of the mapping is not 0.
304	311	</para>
305	312	<para>
306		- Each <filename>mapX/</filename> directory contains two read-only files
307		- that show start address and size of the memory:
	313	+ Each <filename>mapX/</filename> directory contains four read-only files
	314	+ that show attributes of the memory:
308	315	</para>
309	316	<itemizedlist>
310	317	<listitem>
311	318	<para>
	319	+ <filename>name</filename>: A string identifier for this mapping. This
	320	+ is optional, the string can be empty. Drivers can set this to make it
	321	+ easier for userspace to find the correct mapping.
	322	+ </para>
	323	+</listitem>
	324	+<listitem>
	325	+ <para>
312	326	<filename>addr</filename>: The address of memory that can be mapped.
313	327	</para>
314	328	</listitem>
315	329
...	...	@@ -366,10 +380,17 @@
366	380	<filename>/sys/class/uio/uioX/portio/</filename>.
367	381	</para>
368	382	<para>
369		- Each <filename>portX/</filename> directory contains three read-only
370		- files that show start, size, and type of the port region:
	383	+ Each <filename>portX/</filename> directory contains four read-only
	384	+ files that show name, start, size, and type of the port region:
371	385	</para>
372	386	<itemizedlist>
	387	+<listitem>
	388	+ <para>
	389	+ <filename>name</filename>: A string identifier for this port region.
	390	+ The string is optional and can be empty. Drivers can set it to make it
	391	+ easier for userspace to find a certain port region.
	392	+ </para>
	393	+</listitem>
373	394	<listitem>
374	395	<para>
375	396	<filename>start</filename>: The first port of this region.
...	...	@@ -61,6 +61,14 @@
61	61	};
62	62	#define to_map(map) container_of(map, struct uio_map, kobj)
63	63
	64	+static ssize_t map_name_show(struct uio_mem mem, char buf)
	65	+{
	66	+ if (unlikely(!mem->name))
	67	+ mem->name = "";
	68	+
	69	+ return sprintf(buf, "%s\n", mem->name);
	70	+}
	71	+
64	72	static ssize_t map_addr_show(struct uio_mem mem, char buf)
65	73	{
66	74	return sprintf(buf, "0x%lx\n", mem->addr);
...	...	@@ -82,6 +90,8 @@
82	90	ssize_t (store)(struct uio_mem , const char *, size_t);
83	91	};
84	92
	93	+static struct map_sysfs_entry name_attribute =
	94	+ __ATTR(name, S_IRUGO, map_name_show, NULL);
85	95	static struct map_sysfs_entry addr_attribute =
86	96	__ATTR(addr, S_IRUGO, map_addr_show, NULL);
87	97	static struct map_sysfs_entry size_attribute =
...	...	@@ -90,6 +100,7 @@
90	100	__ATTR(offset, S_IRUGO, map_offset_show, NULL);
91	101
92	102	static struct attribute *attrs[] = {
	103	+ &name_attribute.attr,
93	104	&addr_attribute.attr,
94	105	&size_attribute.attr,
95	106	&offset_attribute.attr,
...	...	@@ -133,6 +144,14 @@
133	144	};
134	145	#define to_portio(portio) container_of(portio, struct uio_portio, kobj)
135	146
	147	+static ssize_t portio_name_show(struct uio_port port, char buf)
	148	+{
	149	+ if (unlikely(!port->name))
	150	+ port->name = "";
	151	+
	152	+ return sprintf(buf, "%s\n", port->name);
	153	+}
	154	+
136	155	static ssize_t portio_start_show(struct uio_port port, char buf)
137	156	{
138	157	return sprintf(buf, "0x%lx\n", port->start);
...	...	@@ -159,6 +178,8 @@
159	178	ssize_t (store)(struct uio_port , const char *, size_t);
160	179	};
161	180
	181	+static struct portio_sysfs_entry portio_name_attribute =
	182	+ __ATTR(name, S_IRUGO, portio_name_show, NULL);
162	183	static struct portio_sysfs_entry portio_start_attribute =
163	184	__ATTR(start, S_IRUGO, portio_start_show, NULL);
164	185	static struct portio_sysfs_entry portio_size_attribute =
...	...	@@ -167,6 +188,7 @@
167	188	__ATTR(porttype, S_IRUGO, portio_porttype_show, NULL);
168	189
169	190	static struct attribute *portio_attrs[] = {
	191	+ &portio_name_attribute.attr,
170	192	&portio_start_attribute.attr,
171	193	&portio_size_attribute.attr,
172	194	&portio_porttype_attribute.attr,
...	...	@@ -22,6 +22,7 @@
22	22
23	23	/**
24	24	* struct uio_mem - description of a UIO memory region
	25	+ * @name: name of the memory region for identification
25	26	* @addr: address of the device's memory
26	27	* @size: size of IO
27	28	* @memtype: type of memory addr points to
...	...	@@ -29,6 +30,7 @@
29	30	* @map: for use by the UIO core only.
30	31	*/
31	32	struct uio_mem {
	33	+ const char *name;
32	34	unsigned long addr;
33	35	unsigned long size;
34	36	int memtype;
35	37
...	...	@@ -42,12 +44,14 @@
42	44
43	45	/**
44	46	* struct uio_port - description of a UIO port region
	47	+ * @name: name of the port region for identification
45	48	* @start: start of port region
46	49	* @size: size of port region
47	50	* @porttype: type of port (see UIO_PORT_* below)
48	51	* @portio: for use by the UIO core only.
49	52	*/
50	53	struct uio_port {
	54	+ const char *name;
51	55	unsigned long start;
52	56	unsigned long size;
53	57	int porttype;