diff mbox

[v2,2/2] Add uio_dmem_genirq description to UIO documentation

Message ID 1348553352-14334-3-git-send-email-dhobsong@igel.co.jp (mailing list archive)
State Awaiting Upstream
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Commit Message

Damian Hobson-Garcia Sept. 25, 2012, 6:09 a.m. UTC
Signed-off-by: Damian Hobson-Garcia <dhobsong@igel.co.jp>
---
 Documentation/DocBook/uio-howto.tmpl |   56 ++++++++++++++++++++++++++++++++++
 1 files changed, 56 insertions(+), 0 deletions(-)

Comments

Hans J. Koch Sept. 26, 2012, 11:41 p.m. UTC | #1
On Tue, Sep 25, 2012 at 03:09:12PM +0900, Damian Hobson-Garcia wrote:
> Signed-off-by: Damian Hobson-Garcia <dhobsong@igel.co.jp>

Signed-off-by: "Hans J. Koch" <hjk@hansjkoch.de>

> ---
>  Documentation/DocBook/uio-howto.tmpl |   56 ++++++++++++++++++++++++++++++++++
>  1 files changed, 56 insertions(+), 0 deletions(-)
> 
> diff --git a/Documentation/DocBook/uio-howto.tmpl b/Documentation/DocBook/uio-howto.tmpl
> index ac3d001..db08c1a 100644
> --- a/Documentation/DocBook/uio-howto.tmpl
> +++ b/Documentation/DocBook/uio-howto.tmpl
> @@ -719,6 +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.
> +	Simiar 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 dynmaic 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 DMA_ERROR_CODE.
> +	</para>
> +</sect1>
> +
>  </chapter>
>  
>  <chapter id="userspace_driver" xreflabel="Writing a driver in user space">
> -- 
> 1.7.5.4
> 
> 
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diff mbox

Patch

diff --git a/Documentation/DocBook/uio-howto.tmpl b/Documentation/DocBook/uio-howto.tmpl
index ac3d001..db08c1a 100644
--- a/Documentation/DocBook/uio-howto.tmpl
+++ b/Documentation/DocBook/uio-howto.tmpl
@@ -719,6 +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.
+	Simiar 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 dynmaic 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 DMA_ERROR_CODE.
+	</para>
+</sect1>
+
 </chapter>
 
 <chapter id="userspace_driver" xreflabel="Writing a driver in user space">