Felipe,
On 05/13/2015 10:31 AM, Felipe Balbi wrote:
Hi,
On Wed, May 13, 2015 at 10:18:03AM -0500, Bin Liu wrote:
Felipe,
On 05/12/2015 05:11 PM, Felipe Balbi wrote:
As it turns out, all we have to do is set
Session bit and MUSB will figure out automatically,
based on ID pin, if it should enter host or
peripheral roles.
Signed-off-by: Felipe Balbi <balbi@xxxxxx>
---
drivers/usb/musb/musb_dsps.c | 43 +++++++++++--------------------------------
1 file changed, 11 insertions(+), 32 deletions(-)
diff --git a/drivers/usb/musb/musb_dsps.c b/drivers/usb/musb/musb_dsps.c
index 659c1099b21f..e7d2d1eb1270 100644
--- a/drivers/usb/musb/musb_dsps.c
+++ b/drivers/usb/musb/musb_dsps.c
@@ -253,45 +253,24 @@ static void otg_timer(unsigned long _musb)
const struct dsps_musb_wrapper *wrp = glue->wrp;
u8 devctl;
unsigned long flags;
- int skip_session = 0;
/*
* We poll because DSPS IP's won't expose several OTG-critical
* status change events (from the transceiver) otherwise.
*/
- devctl = dsps_readb(mregs, MUSB_DEVCTL);
- dev_dbg(musb->controller, "Poll devctl %02x (%s)\n", devctl,
- usb_otg_state_string(musb->xceiv->otg->state));
-
spin_lock_irqsave(&musb->lock, flags);
- switch (musb->xceiv->otg->state) {
- case OTG_STATE_A_WAIT_BCON:
- dsps_writeb(musb->mregs, MUSB_DEVCTL, 0);
- skip_session = 1;
- /* fall */
-
- case OTG_STATE_A_IDLE:
- case OTG_STATE_B_IDLE:
- if (devctl & MUSB_DEVCTL_BDEVICE) {
- musb->xceiv->otg->state = OTG_STATE_B_IDLE;
- MUSB_DEV_MODE(musb);
- } else {
- musb->xceiv->otg->state = OTG_STATE_A_IDLE;
- MUSB_HST_MODE(musb);
- }
- if (!(devctl & MUSB_DEVCTL_SESSION) && !skip_session)
- dsps_writeb(mregs, MUSB_DEVCTL, MUSB_DEVCTL_SESSION);
- mod_timer(&glue->timer, jiffies +
- msecs_to_jiffies(wrp->poll_timeout));
- break;
- case OTG_STATE_A_WAIT_VFALL:
- musb->xceiv->otg->state = OTG_STATE_A_WAIT_VRISE;
- dsps_writel(musb->ctrl_base, wrp->coreintr_set,
- MUSB_INTR_VBUSERROR << wrp->usb_shift);
- break;
This case is for handling VBUSERROR recovery. I am wondering removing
it breaks the recovery.
no idea how to test that.
You can remove the VBUS cap, then plug in a thumb drive or hub will most
likely generate the VBUSERROR interrupt. I think what I did was just
short VBUS to ground very quickly.
- default:
- break;
+ devctl = dsps_readb(mregs, MUSB_DEVCTL);
+ if (devctl & MUSB_DEVCTL_SESSION) {
+ goto out;
+ } else {
+ devctl |= MUSB_DEVCTL_SESSION;
+ dsps_writeb(mregs, MUSB_DEVCTL, devctl);
Is it guaranteed this is for A_IDLE and B_IDLE states? The original
code has otg state check.
that check was pointless. This will only do anything when we don't have
anything on the other end, so we will always be either in a_idle or
b_idle.
It is OK if that was the case. I was wondering if otg_timer() will be
fired in wrong state which causes SESSION to be set unintentionally.
Regards,
-Bin.
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