Messages in this thread Patch in this message |  | | Date | Sun, 25 Sep 2022 21:21:03 +0200 | Subject | Re: [PATCH v4] usb: dwc3: Don't switch OTG -> peripheral if extcon is present | From | Ferry Toth <> |
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Hi,
Promising results below.
Op 24-09-2022 om 23:29 schreef Ferry Toth: > Hi, > > One more test > > Op 23-09-2022 om 20:23 schreef Andrey Smirnov: >> On Fri, Sep 23, 2022 at 9:42 AM Andy Shevchenko >> <andriy.shevchenko@intel.com> wrote: >>> On Thu, Sep 22, 2022 at 04:32:55PM -0700, Andrey Smirnov wrote: >>>> On Thu, Sep 22, 2022 at 3:23 AM Ferry Toth <fntoth@gmail.com> wrote: >>>>> On 22-09-2022 12:08, Andy Shevchenko wrote: >>>>> On Sun, Apr 03, 2022 at 09:49:07AM -0700, Andrey Smirnov wrote: >>> FYI: For now I sent a revert, but if we got a solution quicker we >>> always >>> can choose the course of actions. >>> >> I think we have another problem. This patch happened in parallel to mine >> >> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?h=v6.0-rc6&id=ab7aa2866d295438dc60522f85c5421c6b4f1507 >> >> >> so my changes didn't have that fix in mind and I think your revert >> will not preserve that fix. Can you update your revert to take care of >> that too, please? >> >> I'm really confused how the above commit could be followed up by: >> >> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/drivers/usb/dwc3/drd.c?h=v6.0-rc6&id=0f01017191384e3962fa31520a9fd9846c3d352f >> >> >> the diffs in dwc3_drd_init seem contradictory >> >>>>> If the extcon device exists, get the mode from the extcon device. If >>>>> the controller is DRD and the driver is unable to determine the mode, >>>>> only then default the dr_mode to USB_DR_MODE_PERIPHERAL. >>>>> >>>>> According to Ferry (Cc'ed) this broke Intel Merrifield platform. >>>>> Ferry, can you >>>>> share bisect log? >>>>> >>>>> I can but not right now. But what I did was bisect between 5.18.0 >>>>> (good) and 5.19.0 (bad) then when I got near the culprit (~20 >>>>> remaining) based on the commit message I tried >>>>> 0f01017191384e3962fa31520a9fd9846c3d352f "usb: dwc3: Don't switch >>>>> OTG -> peripheral if extcon is present" (bad) and commit before >>>>> that (good). >>>>> >>>>> The effect of the patch is that on Merrifield (I tested with Intel >>>>> Edison Arduino board which has a HW switch to select between host >>>>> and device mode) device mode works but in host mode USB is >>>>> completely not working. >>>>> >>>>> Currently on host mode - when working - superfluous error messages >>>>> from tusb1210 appear. When host mode is not working there are no >>>>> tusb1210 messages in the logs / on the console at all. Seemingly >>>>> tusb1210 is not probed, which points in the direction of a >>>>> relation to extcon. >>>>> >>>>> Taking into account the late cycle, I would like to revert the >>>>> change. And >>>>> Ferry and I would help to test any other (non-regressive) approach). >>>>> >>>>> I have not yet tested if a simple revert fixes the problem but >>>>> will tonight. >>>>> >>>>> >>>>> I would be happy to test other approaches too. >>>> >>>> It's a bit hard for me to suggest an alternative approach without >>>> knowing how things are breaking in this case. I'd love to order one of >>>> those boards to repro and fix this on my end, but it looks like this >>>> HW is EOLed and out of stock in most places. If you guys know how to >>>> get my hands on those boards I'm all ears. >>> There are still some second hand Intel Edison boards flying around >>> (but maybe cost a bit more than expected) and there are also >>> Dell Venue 7 3740 tablets based on the same platform/SoC. The latter >>> option though requires more actions in order something to be boot >>> there. >>> >> OK, I'll check e-bay just in case. >> >>> In any case, it's probably quicker to ask Ferry or me for testing. >>> (Although currently I have no access to the board to test OTG, it's >>> remote device which I can only power on and off and it has always >>> be in host mode.) >>> >>>> Barring that, Ferry can you dig more into this failure? E.g. is it >>>> this hunk >>>> >>>> @@ -85,7 +86,7 @@ static int dwc3_get_dr_mode(struct dwc3 *dwc) >>>> * mode. If the controller supports DRD but the >>>> dr_mode is not >>>> * specified or set to OTG, then set the mode to >>>> peripheral. >>>> */ >>>> - if (mode == USB_DR_MODE_OTG && >>>> + if (mode == USB_DR_MODE_OTG && !dwc->edev && >>>> (!IS_ENABLED(CONFIG_USB_ROLE_SWITCH) || >>>> !device_property_read_bool(dwc->dev, "usb-role-switch")) && >>>> !DWC3_VER_IS_PRIOR(DWC3, 330A)) >>>> @@ -1632,6 +1633,51 @@ static void dwc3_check_params(struct dwc3 *dwc) >>>> } >>>> } >>>> >>>> that's problematic or moving >>> I think you wanted to revert only this line and test? >> Yes. >> >>>> static int dwc3_probe(struct platform_device *pdev) >>>> { >>>> struct device *dev = &pdev->dev; >>>> @@ -1744,6 +1790,13 @@ static int dwc3_probe(struct platform_device >>>> *pdev) >>>> goto err2; >>>> } >>>> >>>> + dwc->edev = dwc3_get_extcon(dwc); >>>> + if (IS_ERR(dwc->edev)) { >>>> + ret = PTR_ERR(dwc->edev); >>>> + dev_err_probe(dwc->dev, ret, "failed to get >>>> extcon\n"); >>>> + goto err3; >>>> + } >>>> + >>>> ret = dwc3_get_dr_mode(dwc); >>>> if (ret) >>>> goto err3; >>>> >>>> to happen earlier? > > I tried moving dwc3_get_extcon after dwc3_get_dr_mode like so:: > > diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c > index 8c8e32651473..3bf370def546 100644 > --- a/drivers/usb/dwc3/core.c > +++ b/drivers/usb/dwc3/core.c > @@ -1843,6 +1843,10 @@ static int dwc3_probe(struct platform_device > *pdev) > goto err2; > } > > + ret = dwc3_get_dr_mode(dwc); > + if (ret) > + goto err3; > + > dwc->edev = dwc3_get_extcon(dwc); > if (IS_ERR(dwc->edev)) { > ret = PTR_ERR(dwc->edev); > @@ -1850,10 +1854,6 @@ static int dwc3_probe(struct platform_device > *pdev) > goto err3; > } > > - ret = dwc3_get_dr_mode(dwc); > - if (ret) > - goto err3; > - > ret = dwc3_alloc_scratch_buffers(dwc); > if (ret) > goto err3;
After trying to understand the code a bit, I successfully tested the following move:
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c index 8c8e32651473..4a38cff8cb16 100644 --- a/drivers/usb/dwc3/core.c +++ b/drivers/usb/dwc3/core.c @@ -1843,13 +1843,6 @@ static int dwc3_probe(struct platform_device *pdev) goto err2; }
- dwc->edev = dwc3_get_extcon(dwc); - if (IS_ERR(dwc->edev)) { - ret = PTR_ERR(dwc->edev); - dev_err_probe(dwc->dev, ret, "failed to get extcon\n"); - goto err3; - } - ret = dwc3_get_dr_mode(dwc); if (ret) goto err3; @@ -1867,6 +1860,13 @@ static int dwc3_probe(struct platform_device *pdev) dwc3_check_params(dwc); dwc3_debugfs_init(dwc);
+ dwc->edev = dwc3_get_extcon(dwc); + if (IS_ERR(dwc->edev)) { + ret = PTR_ERR(dwc->edev); + dev_err_probe(dwc->dev, ret, "failed to get extcon\n"); + goto err5; + } + ret = dwc3_core_init_mode(dwc); if (ret) goto err5; This moves dwc3_get_extcon() until after dwc3_core_init() but just before dwc3_core_init_mode(). AFAIU initially dwc3_get_extcon() was called from within dwc3_core_init_mode() but only for case USB_DR_MODE_OTG. So with this change order of events is more or less unchanged.
Due to move I modified goto to err5, not sure if that is correct.
Thoughts? Can we get something like this in quick or should we revert first?
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