usb: musb: cppi41: don't check early-TX-interrupt for Isoch transfer
commit51a3f3ec531adb09e96ea38b8dd8f21a4321d6ed
authorBin Liu <b-liu@ti.com>
Fri, 10 Mar 2017 20:43:35 +0000 (10 14:43 -0600)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 30 Mar 2017 07:41:24 +0000 (30 09:41 +0200)
treeb83d3dfa1a3ddb0742c7a56ededd59e9577ca806
parent46aeeb2ac18acdaee65355d335b63fa2a49ac01b
usb: musb: cppi41: don't check early-TX-interrupt for Isoch transfer

commit 0090114d336a9604aa2d90bc83f20f7cd121b76c upstream.

The CPPI 4.1 driver polls register to workaround the premature TX
interrupt issue, but it causes audio playback underrun when triggered in
Isoch transfers.

Isoch doesn't do back-to-back transfers, the TX should be done by the
time the next transfer is scheduled. So skip this polling workaround for
Isoch transfer.

Fixes: a655f481d83d6 ("usb: musb: musb_cppi41: handle pre-mature TX complete interrupt")
Reported-by: Alexandre Bailon <abailon@baylibre.com>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: Alexandre Bailon <abailon@baylibre.com>
Signed-off-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/musb/musb_cppi41.c