usb: musb: Add musb_set_host and peripheral and use them for omap2430

At least some revisions of musb core need to set devctl session bit
in peripheral mode to force musb to host mode. And we have places
clearing the devctl session bit.

Let's add a generic function to do this, and use it for omap2430.
This should get us a bit closer to completely removing devctl register
tinkering in the SoC glue code.

Before making use of this code for the other glue layers, things need
to be tested carefully as there may be a approximately a 200 ms delay
needed between powering up musb and calling musb_set_host() to avoid.
Otherwise the system hangs at least with omap2430 glue layer.

Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Tony Lindgren <tony@atomide.com>
[b-liu@ti.com: fixed "line over 80 characters" warning]
Signed-off-by: Bin Liu <b-liu@ti.com>
Link: https://lore.kernel.org/r/20200115132547.364-8-b-liu@ti.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/usb/musb/musb_core.h b/drivers/usb/musb/musb_core.h
index 04203b7126d5..8a13a46cd891 100644
--- a/drivers/usb/musb/musb_core.h
+++ b/drivers/usb/musb/musb_core.h
@@ -487,6 +487,9 @@ extern void musb_start(struct musb *musb);
 extern void musb_write_fifo(struct musb_hw_ep *ep, u16 len, const u8 *src);
 extern void musb_read_fifo(struct musb_hw_ep *ep, u16 len, u8 *dst);
 
+extern int musb_set_host(struct musb *musb);
+extern int musb_set_peripheral(struct musb *musb);
+
 extern void musb_load_testpacket(struct musb *);
 
 extern irqreturn_t musb_interrupt(struct musb *);