Hi,
On 05-08-15 00:57, Felipe Balbi wrote:
Hi,
On Wed, Aug 05, 2015 at 12:05:02AM +0200, Hans de Goede wrote:
Hi,
On 08/04/2015 11:35 PM, Felipe Balbi wrote:
On Tue, Aug 04, 2015 at 11:25:53PM +0200, Hans de Goede wrote:
For some unclear reason sometimes we get VBus errors in host-only mode,
even though we do not have any vbus-detection then. Ignore these.
Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
---
drivers/usb/musb/sunxi.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/drivers/usb/musb/sunxi.c b/drivers/usb/musb/sunxi.c
index f9f6304..34ce5df 100644
--- a/drivers/usb/musb/sunxi.c
+++ b/drivers/usb/musb/sunxi.c
@@ -194,6 +194,10 @@ static irqreturn_t sunxi_musb_interrupt(int irq, void *__hci)
musb_writeb(musb->mregs, MUSB_FADDR, 0);
}
+ /* Ignore Vbus errors when in host only mode */
+ if (musb->port_mode == MUSB_PORT_MODE_HOST)
+ musb->int_usb &= ~MUSB_INTR_VBUSERROR;
check with a scope if VBUS is really dropping. Host does VBUS detection
indeed, at a minimum, for overcurrent protection. You might have
something causing VBUS to drop and that something needs to be found,
rather than masked.
The boards in question do not have any vbus detection, the usb-phy on
allwinner boards do not have a vbus sense pin, instead a gpio is used
in designs which use otg. Designs which use host-only mode typically
do not have any form of vbus detection at all. In this case we always
report vbus as being valid to the musb core, so I've no idea why
the musb core is still generating vbus errors.
PHY must tell MUSB about VBUS level using either ULPI or UTMI+. I'd
check to see if the PHY is at fault, at least.
Right, and the phy code has:
if (data->id_det_gpio) {
/* OTG mode, force ISCR and cable state updates */
data->id_det = -1;
data->vbus_det = -1;
queue_delayed_work(system_wq, &data->detect, 0);
} else {
/* Host only mode */
sun4i_usb_phy0_set_id_detect(_phy, 0);
sun4i_usb_phy0_set_vbus_detect(_phy, 1);
}
Where we enter the host only path (no id-pin in host only mode) and
then sun4i_usb_phy0_set_vbus_detect updates the ISCR register of
the phy to make it report vbus valid. I've done an mmio-dump of
the iscr register while running Linux, and this code does the right
thing.
I agree with you that this is weird, but atm I see no other way
to fix this then the submitted patch.
Regards,
Hans
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