@@ -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:
This is a note to let you know that I have just added a patch titled usb: musb: call musb_start() only once in OTG mode to the linux-3.11.y-queue branch of the 3.11.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.11.y-queue If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.11.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From 26d6aa2c327dfd4c8dd2d9a94affff2cb6f29ec1 Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Tue, 15 Oct 2013 18:29:22 +0200 Subject: 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: Luis Henriques <luis.henriques@canonical.com> --- drivers/usb/musb/musb_virthub.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) -- 1.8.3.2