spin lock was very effective while doing 1 packet send/recv on
current renesas_usbhs driver.
But this lock is enough only
 - modify packet/pipe link
 - modify interrpt mask
 - modify fifo access
This patch shrink spin lock area
Signed-off-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

On current driver, overall data transfer method was implemented in fifo.c,
but its interrupt which is member of packet queue control
was still in mod_gadget.c.
This patch move it into fifo.c.
By this patch, the packet/fifo control is independent from mod_gadget.
Signed-off-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

On current driver, main data transfer function was implemented in fifo.c,
but the overall controlling was implementing in mod_gadget.c.
This style is not useful to support host and DMAEngine in the future.

But the interrupt for data transfer cannot separate easily for now,
because it is deeply related to mod_gadget.

This patch move the overall data transfer method
into fifo.c except interrupt.
Signed-off-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Current renesas_usbhs driver is controlling packet queue on mod_gadget.c.
But it has relationship with pipe/fifo, not host/gadget.
So, controlling USB packet queue in pipe.c/fifo.c is
more convenient than in mod_gadget.c.
This patch modify it.
Signed-off-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

DMAEngine will be supported to this driver in the future.
Then, both PIO and DMA data transfer method should be supported.
But, the transfer function can returns the result immediately
in PIO version, but it can't in DMA version.
This patch divides data transfer functions into top/bottom half
in preparation for DMAEngine support.
Signed-off-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

Current renesas_usbhs has PIO data transfer mode which controls CFIFO.
And it was implemented in pipe.c.
But, fifo control method needs more flexible implementation
to support DMAEngine.
This patch create fifo.c, and it became independent from pipe.c.
Signed-off-by: NKuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>