* Bin Liu | 2013-07-26 22:07:14 [-0500]:
>Sebastian,
Hi Bin,
>I have not tested it yet, but I believe I found why host mode works on
>TI 3.2 kernel but not on mainline. Please look at Line 786 in 3.2
>kernel musb_core.c [1].
>
>773 if ((int_usb & MUSB_INTR_DISCONNECT) && !musb->ignore_disconnect) {
>......
>785 if (musb->a_wait_bcon != 0 &&
>786 is_otg_enabled(musb))
>787 musb_platform_try_idle(musb, jiffies
>788 +
>msecs_to_jiffies(musb->a_wait_bcon));
>
>So when the device is unplugged, *_try_idle() is not called in host
>mode, then the SESSION bit will stay set. But in mainline kernel,
>*_try_idle() will be called regardless.
>
>Please let me know your thoughts.
I am not too familiar with what should happen. The is_otg_enabled() part
is gone since v3.7-rc1 via:
|commit 032ec49f5351e9cb242b1a1c367d14415043ab95
|Author: Felipe Balbi <balbi@xxxxxx>
|Date: Thu Nov 24 15:46:26 2011 +0200
|
| usb: musb: drop useless board_mode usage
|
| we are compiling the driver always with full OTG
| capabilities, so that board_mode trick becomes
| useless.
|
| Signed-off-by: Felipe Balbi <balbi@xxxxxx>
So you say, am335x-evm is not able to run OTG mode and may only run in
host mode and as a consequence it must not call musb_platform_try_idle()
because it throws that one bit away and there is no way to bring it back?
However, if I look at the tree you reference, I see in
arch/arm/mach-omap2/board-am335xevm.c:
| static struct omap_musb_board_data musb_board_data = {
| .interface_type = MUSB_INTERFACE_ULPI,
| .mode = MUSB_OTG,
| .power = 500,
| .instances = 1,
| };
…
| static void __init am335x_evm_init(void)
…
| usb_musb_init(&musb_board_data);
and it creates a "ti81xx-usbss" device.
So it creates a musb device with mode MUSB_OTG no matter what.
I agree that without that try_idle part things keep working but it
seems, that it is also called in the other tree.
>
>Regards,
>-Bin.
Sebastian
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