diff options
author | Sebastian Andrzej Siewior <bigeasy@linutronix.de> | 2013-10-15 16:29:22 (GMT) |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-11-29 19:28:11 (GMT) |
commit | 43ac9e1999b72122ee20e942263584f95d993aaa (patch) | |
tree | fa9914ab603eb45fcb21b68a61f1e3d1c79a0269 | |
parent | bbc21afd5bd6d52976d74afc73ef2a9e9db631e6 (diff) | |
download | linux-fsl-qoriq-43ac9e1999b72122ee20e942263584f95d993aaa.tar.xz |
usb: musb: call musb_start() only once in OTG mode
commit ae44df2e21b50f9fff28ac75c57e399c04df812c upstream.
In commit 001dd84 ("usb: musb: start musb on the udc side, too") it was
ensured that the state engine is started also in OTG mode after a
removal / insertion of the gadget.
Unfortunately this change also introduced a bug: If the device is
configured as OTG and it connected with a remote host _without_ loading
a gadget then we bug() later (because musb->otg->gadget is not
initialized).
Initially I assumed it might be nice to have the host part of musb in
OTG mode working without having a gadget loaded. This bug and fact that
it wasn't working like this before the host/gadget split made me realize
that this was a silly idea.
This patch now introduces back the old behavior where in OTG mode the
host mode is only working after the gadget has been loaded.
Cc: Daniel Mack <zonque@gmail.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | drivers/usb/musb/musb_virthub.c | 19 |
1 files changed, 18 insertions, 1 deletions
diff --git a/drivers/usb/musb/musb_virthub.c b/drivers/usb/musb/musb_virthub.c index d1d6b83..9af6bba 100644 --- a/drivers/usb/musb/musb_virthub.c +++ b/drivers/usb/musb/musb_virthub.c @@ -220,6 +220,23 @@ int musb_hub_status_data(struct usb_hcd *hcd, char *buf) return retval; } +static int musb_has_gadget(struct musb *musb) +{ + /* + * In host-only mode we start a connection right away. In OTG mode + * we have to wait until we loaded a gadget. We don't really need a + * gadget if we operate as a host but we should not start a session + * as a device without a gadget or else we explode. + */ +#ifdef CONFIG_USB_MUSB_HOST + return 1; +#else + if (musb->port_mode == MUSB_PORT_MODE_HOST) + return 1; + return musb->g.dev.driver != NULL; +#endif +} + int musb_hub_control( struct usb_hcd *hcd, u16 typeReq, @@ -362,7 +379,7 @@ int musb_hub_control( * initialization logic, e.g. for OTG, or change any * logic relating to VBUS power-up. */ - if (!hcd->self.is_b_host) + if (!hcd->self.is_b_host && musb_has_gadget(musb)) musb_start(musb); break; case USB_PORT_FEAT_RESET: |