DOC: A couple corrections and clarifications in USB doc.
A couple of corrections and clarifications in USB documentation. Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca> Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
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@ -100,8 +100,8 @@
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useful documents, at the USB home page (see Resources). An excellent
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introduction to the Linux USB subsystem can be found at the USB Working
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Devices List (see Resources). It explains how the Linux USB subsystem is
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structured and introduces the reader to the concept of USB urbs, which
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are essential to USB drivers.
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structured and introduces the reader to the concept of USB urbs
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(USB Request Blocks), which are essential to USB drivers.
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</para>
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<para>
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The first thing a Linux USB driver needs to do is register itself with
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@ -162,8 +162,8 @@ static int __init usb_skel_init(void)
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module_init(usb_skel_init);
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</programlisting>
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<para>
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When the driver is unloaded from the system, it needs to unregister
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itself with the USB subsystem. This is done with the usb_unregister
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When the driver is unloaded from the system, it needs to deregister
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itself with the USB subsystem. This is done with the usb_deregister
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function:
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</para>
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<programlisting>
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@ -232,7 +232,7 @@ static int skel_probe(struct usb_interface *interface,
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were passed to the USB subsystem will be called from a user program trying
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to talk to the device. The first function called will be open, as the
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program tries to open the device for I/O. We increment our private usage
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count and save off a pointer to our internal structure in the file
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count and save a pointer to our internal structure in the file
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structure. This is done so that future calls to file operations will
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enable the driver to determine which device the user is addressing. All
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of this is done with the following code:
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@ -252,8 +252,8 @@ file->private_data = dev;
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send to the device based on the size of the write urb it has created (this
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size depends on the size of the bulk out end point that the device has).
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Then it copies the data from user space to kernel space, points the urb to
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the data and submits the urb to the USB subsystem. This can be shown in
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he following code:
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the data and submits the urb to the USB subsystem. This can be seen in
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the following code:
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</para>
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<programlisting>
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/* we can only write as much as 1 urb will hold */
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