Promote line6 driver from staging to sound/usb/line6 directory, and
maintain through sound subsystem tree.

This commit just moves the code and adapts Makefile / Kconfig.
The further renames and misc cleanups will follow.
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Remove declarations from the header and move the definitions up in the
source so they need not be forward declared.
Signed-off-by: NChris Rorvick <chris@rorvick.com>
Reviewed-by: NStefan Hajnoczi <stefanha@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Which *_disconnect() to call on disconnect is known at initialization.
Add a function pointer to the `usb_line6' struct and use to call into
the appropriate logic instead of evaluating the conditional logic.
Signed-off-by: NChris Rorvick <chris@rorvick.com>
Reviewed-by: NStefan Hajnoczi <stefanha@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

Casting the `struct usb_line6' pointer at the call point makes the code
difficult to read.  This is substantially cleaned up by moving the cast
into the callees.
Signed-off-by: NChris Rorvick <chris@rorvick.com>
Reviewed-by: NStefan Hajnoczi <stefanha@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

The line6 driver checks struct field addresses for NULL where it does
not make sense to do so.  The struct has already been checked for NULL
and there is no value in checking the first field's address too.
Suggested-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NStefan Hajnoczi <stefanha@gmail.com>
Signed-off-by: NMarkus Grabner <grabner@icg.tugraz.at>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

The Pod HD device family uses new MIDI SysEx messages and therefore
cannot reuse the existing Pod code.  Instead of hardcoding Pod HD MIDI
messages into the driver, leave MIDI up to userspace.  This driver
simply presents MIDI and pcm ALSA devices.

This device is similar to the Pod except that it has 48 kHz audio and
does not respond to Pod SysEx messages.
Signed-off-by: NStefan Hajnoczi <stefanha@gmail.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>