George, On Wed, May 14, 2014 at 12:37 AM, George Cherian <george.cherian@xxxxxx> wrote: > On 5/14/2014 12:07 AM, Bin Liu wrote: >> >> Hi, >> >> On Tue, May 13, 2014 at 8:24 AM, George Cherian <george.cherian@xxxxxx> >> wrote: >>> >>> Hi Daniel, >>> >>> >>> On 5/13/2014 6:44 PM, Daniel Mack wrote: >>>> >>>> Hi George, >>>> >>>> On 05/13/2014 02:57 PM, George Cherian wrote: >>>>> >>>>> I never enabled the MUSB_BABBLE_SW_SESSION_CTRL in the MUSB_BABBLE_CTL >>>>> reg. >>>>> can you try with the following patch. >>>>> >>>>> diff --git a/drivers/usb/musb/musb_dsps.c >>>>> b/drivers/usb/musb/musb_dsps.c >>>>> index 1ae6681..1160cd1 100644 >>>>> --- a/drivers/usb/musb/musb_dsps.c >>>>> +++ b/drivers/usb/musb/musb_dsps.c >>>>> @@ -477,8 +477,11 @@ static int dsps_musb_init(struct musb *musb) >>>>> * logic enabled. >>>>> */ >>>>> val = dsps_readb(musb->mregs, MUSB_BABBLE_CTL); >>>>> - if (val == MUSB_BABBLE_RCV_DISABLE) >>>>> + if (val == MUSB_BABBLE_RCV_DISABLE) { >>>>> glue->sw_babble_enabled = true; >>>>> + val |= MUSB_BABBLE_SW_SESSION_CTRL; >>>>> + dsps_writeb(musb->mregs, MUSB_BABBLE_CTL, val); >>>>> + } >>>>> ret = dsps_musb_dbg_init(musb, glue); >>>>> if (ret) >>>> >>>> MUSB_BABBLE_STUCK_J still remains unset, so I get the same result as >>>> without the patch: a full glue reset is conducted. Do I get you right >>>> that you expect MUSB_BABBLE_STUCK_J to be set in babble conditions when >>>> MUSB_BABBLE_SW_SESSION_CTRL is set? >>>> >>> Basically, there are 2 types of babble conditions. >>> 1) Transient babble condition - which could be recovered from without an >>> IP >>> reset . >>> 2) Babble condition - which could be recovered from only by doing an IP >>> reset. >>> >>> Looks like you are always hitting case 2 (Most times am also hitting the >>> same). >>> Case 1 is really hard to reproduce. I don't have a reliable method as of >>> now >>> to >>> reproduce this case consistently. >>> >>>> [ 19.672373] CAUTION: musb: Babble Interrupt Occurred >>>> [ 19.677776] musb_stage0_irq 789: unhandled DISCONNECT transition >>>> (a_wait_bcon) >>>> [ 19.685815] usb 1-1: USB disconnect, device number 3 >>>> [ 19.769720] musb-hdrc musb-hdrc.0.auto: babble: MUSB_BABBLE_CTL value >>>> 44 >>>> [ 19.776765] musb-hdrc musb-hdrc.0.auto: STUCK_J is reset >>>> >>>> >>>> I don't quite follow, especially as I lack documentation of the IP core. >>>> How do you test babble errors, is there any way to force them to happen >>>> reliably? >>> >>> >>> There is no 100% reliable method to force it to happen. Following is >> >> I have a way to force babble happen reliably - shorting DP or DM to >> VBUS. I opened the far-end plug of the USB cable, so I can easily >> short DP or DM to VBUS. > > Good to know that you have a reliable way to test babble condition. > Can you please do a quick test on 3.15.0-rc4 with the series applied? > In case of any assistance please do let me know. Sure, but could you please re-send those patches to my corporate email so that I can apply them from Thunderbird? I read these linux-usb emails in Gmail, and am not aware of any easy way to extract patches from Gmail. BTY, I tested with TI 3.12.10 kernel, in which I guess the babble handling is similar to this patch set. With TI3.12.10, MISC is always 0x64, so MUSB never restarts. Thanks, -Bin. > >> But the interesting thing is that with TI 3.2 kernel, shorting DP or >> DM to VBUS causes MISC register to be 0x4, but the result is >> completely opposite in TI 3.12.10 kernel, which cause MISC to be 0x64. >> >> So in the 3.2 kernel, the babble handing resets the controller, but >> the 3.12.10 does not. >> >> Regards, >> -Bin. >> >>> my setup , >>> I have a HUB with 4 devices connected , which gives me a Babble interrupt >>> on both connects and disconnects ( Not always though). >>> >>>> Anyway, the full glue layer solves this rare condition quite well for >>>> me. Is there any downside of this? >>>> >>>> >>>> Daniel >>>> >>> >>> -- >>> -George >>> >>> -- >>> To unsubscribe from this list: send the line "unsubscribe linux-omap" in >>> >>> the body of a message to majordomo@xxxxxxxxxxxxxxx >>> More majordomo info at http://vger.kernel.org/majordomo-info.html > > > > -- > -George > -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html