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-rw-r--r--Documentation/DocBook/uio-howto.tmpl67
1 files changed, 64 insertions, 3 deletions
diff --git a/Documentation/DocBook/uio-howto.tmpl b/Documentation/DocBook/uio-howto.tmpl
index 7c4b514d62b..bbe9c1fd5ce 100644
--- a/Documentation/DocBook/uio-howto.tmpl
+++ b/Documentation/DocBook/uio-howto.tmpl
@@ -521,6 +521,11 @@ Here's a description of the fields of <varname>struct uio_mem</varname>:
<itemizedlist>
<listitem><para>
+<varname>const char *name</varname>: Optional. Set this to help identify
+the memory region, it will show up in the corresponding sysfs node.
+</para></listitem>
+
+<listitem><para>
<varname>int memtype</varname>: Required if the mapping is used. Set this to
<varname>UIO_MEM_PHYS</varname> if you you have physical memory on your
card to be mapped. Use <varname>UIO_MEM_LOGICAL</varname> for logical
@@ -529,7 +534,7 @@ memory (e.g. allocated with <function>kmalloc()</function>). There's also
</para></listitem>
<listitem><para>
-<varname>unsigned long addr</varname>: Required if the mapping is used.
+<varname>phys_addr_t addr</varname>: Required if the mapping is used.
Fill in the address of your memory block. This address is the one that
appears in sysfs.
</para></listitem>
@@ -553,7 +558,7 @@ instead to remember such an address.
</itemizedlist>
<para>
-Please do not touch the <varname>kobj</varname> element of
+Please do not touch the <varname>map</varname> element of
<varname>struct uio_mem</varname>! It is used by the UIO framework
to set up sysfs files for this mapping. Simply leave it alone.
</para>
@@ -714,6 +719,62 @@ framework to set up sysfs files for this region. Simply leave it alone.
</para>
</sect1>
+<sect1 id="using uio_dmem_genirq">
+<title>Using uio_dmem_genirq for platform devices</title>
+ <para>
+ In addition to statically allocated memory ranges, they may also be
+ a desire to use dynamically allocated regions in a user space driver.
+ In particular, being able to access memory made available through the
+ dma-mapping API, may be particularly useful. The
+ <varname>uio_dmem_genirq</varname> driver provides a way to accomplish
+ this.
+ </para>
+ <para>
+ This driver is used in a similar manner to the
+ <varname>"uio_pdrv_genirq"</varname> driver with respect to interrupt
+ configuration and handling.
+ </para>
+ <para>
+ Set the <varname>.name</varname> element of
+ <varname>struct platform_device</varname> to
+ <varname>"uio_dmem_genirq"</varname> to use this driver.
+ </para>
+ <para>
+ When using this driver, fill in the <varname>.platform_data</varname>
+ element of <varname>struct platform_device</varname>, which is of type
+ <varname>struct uio_dmem_genirq_pdata</varname> and which contains the
+ following elements:
+ </para>
+ <itemizedlist>
+ <listitem><varname>struct uio_info uioinfo</varname>: The same
+ structure used as the <varname>uio_pdrv_genirq</varname> platform
+ data</listitem>
+ <listitem><varname>unsigned int *dynamic_region_sizes</varname>:
+ Pointer to list of sizes of dynamic memory regions to be mapped into
+ user space.
+ </listitem>
+ <listitem><varname>unsigned int num_dynamic_regions</varname>:
+ Number of elements in <varname>dynamic_region_sizes</varname> array.
+ </listitem>
+ </itemizedlist>
+ <para>
+ The dynamic regions defined in the platform data will be appended to
+ the <varname> mem[] </varname> array after the platform device
+ resources, which implies that the total number of static and dynamic
+ memory regions cannot exceed <varname>MAX_UIO_MAPS</varname>.
+ </para>
+ <para>
+ The dynamic memory regions will be allocated when the UIO device file,
+ <varname>/dev/uioX</varname> is opened.
+ Similar to static memory resources, the memory region information for
+ dynamic regions is then visible via sysfs at
+ <varname>/sys/class/uio/uioX/maps/mapY/*</varname>.
+ The dynamic memory regions will be freed when the UIO device file is
+ closed. When no processes are holding the device file open, the address
+ returned to userspace is ~0.
+ </para>
+</sect1>
+
</chapter>
<chapter id="userspace_driver" xreflabel="Writing a driver in user space">
@@ -923,7 +984,7 @@ int main()
return errno;
}
configfd = open(&quot;/sys/class/uio/uio0/device/config&quot;, O_RDWR);
- if (uiofd &lt; 0) {
+ if (configfd &lt; 0) {
perror(&quot;config open:&quot;);
return errno;
}