Re: [PATCH v3] usb: dwc2: add bus suspend/resume for dwc2
On 01/05/2015 09:02 PM, Paul Zimmerman wrote: From: Kever Yang [mailto:kever.y...@rock-chips.com] Sent: Monday, January 05, 2015 5:42 PM Hi Paul, I think you need this patch to fix the problem: usb: dwc2: resume root hub when device detect with suspend state https://patchwork.kernel.org/patch/5325111/ This patch may have fixed hotplug when a device is connected directly to the USB port, but it does not seem to fix a hotplug when a device is connected to a hub. I booted the board up with a device connected to a 4-port hub, the device is detected, unplug the device from a hub, wait 5-sec, re-plug the device into hub. The device is not detected. Thanks, - Kever On 01/06/2015 09:23 AM, Paul Zimmerman wrote: From: Kever Yang [mailto:kever.y...@rock-chips.com] Sent: Wednesday, November 12, 2014 4:42 PM On 11/13/2014 07:22 AM, Doug Anderson wrote: Kever, On Mon, Nov 10, 2014 at 5:09 AM, Kever Yang kever.y...@rock-chips.com wrote: Hcd controller needs bus_suspend/resume, dwc2 controller make root hub generate suspend/resume signal with hprt0 register when work in host mode. After the root hub enter suspend, we can make controller enter low power state with PCGCTL register. We also update the lx_state for hsotg state. This patch has tested on rk3288 with suspend/resume. Signed-off-by: Kever Yang kever.y...@rock-chips.com Acked-by: Paul Zimmerman pa...@synopsys.com --- Changes in v3: - remove CONFIG_PM macro for bus_suspend/resume - add PCGCTL operation for no device connect case Changes in v2: - update commit message - make dwc2 suspend/resume sourcecode work drivers/usb/dwc2/hcd.c | 88 +++--- 1 file changed, 77 insertions(+), 11 deletions(-) I would certainly appreciate confirmation, but my inclination is to NAK this change due to the fact that it regresses functionality. I haven't done any serious review of it, but I've been testing it and it appears to break hotplug. Said another way, I did this: 1. Without this patch, I booted with a USB stick in. It was detected. I unplugged it, waited 5 seconds, and then plugged it back in. The USB stick was redetcted. 2. With this patch, I did the same thing. The USB not redected after plugging it back in. With this patch, the dwc2 hcd/root hub will be auto suspend after device on port is disconnected, and it can't detect the device connect any more, I think that's the problem. I will figure out how to make dwc2 detect the device connect after auto suspend, or disable the auto suspend feature for the dwc2 hcd. Kever, This patch has made it into Linus' kernel as commit 0cf884e819e0, and it breaks disconnect/connect on at least the Altera SOCFPGA platform. I haven't been able to test it on any other platforms. You need to submit a patch to either fix this, or to only enable this feature for the Rock-chip platform. Otherwise the patch has to be reverted. Unfortunately, after applying that patch there is another problem. If I connect a device that causes an overcurrent condition to the root port, then the port is dead after that. No further devices are detected until after I reboot. I tried adding another call to usb_hcd_resume_root_hub() in the if (hprt0 HPRT0_OVRCURRCHG) branch, but then an overcurrent condition causes a continuous stream of these messages: [ 133.348776] dwc2 ffb4.usb: GetPortStatus wIndex=0x0001 flags=0x0022 [ 133.355717] dwc2 ffb4.usb: Overcurrent change detected [ 133.361179] dwc2 ffb4.usb: HPRT0: 0x0002 [ 133.365960] dwc2 ffb4.usb: port_status=0008 [ 133.373236] hub 1-0:1.0: state 7 ports 1 chg evt [ 133.380038] hub 1-0:1.0: hub_suspend [ 133.384237] usb usb1: bus auto-suspend, wakeup 1 [ 133.393631] dwc2 ffb4.usb: DWC OTG HCD HUB STATUS DATA: Root port status changed [ 133.401341] dwc2 ffb4.usb: port_connect_status_change: 0 [ 133.407157] dwc2 ffb4.usb: port_reset_change: 0 [ 133.412186] dwc2 ffb4.usb: port_enable_change: 0 [ 133.417310] dwc2 ffb4.usb: port_suspend_change: 0 [ 133.422519] dwc2 ffb4.usb: port_over_current_change: 1 [ 133.428154] usb usb1: suspend raced with wakeup event [ 133.433191] usb usb1: usb auto-resume [ 133.441522] hub 1-0:1.0: hub_resume [ 133.455505] dwc2 ffb4.usb: GetPortStatus wIndex=0x0001 flags=0x0022 [ 133.462443] dwc2 ffb4.usb: Overcurrent change detected [ 133.467907] dwc2 ffb4.usb: HPRT0: 0x0002 [ 133.472684] dwc2 ffb4.usb: port_status=0008 [ 133.480088] hub 1-0:1.0: state 7 ports 1 chg evt [ 133.485578] hub 1-0:1.0: hub_suspend [ 133.489157] usb usb1: bus auto-suspend, wakeup 1 [ 133.493768] dwc2 ffb4.usb: _dwc2_hcd_suspend() [ 133.498540] dwc2 ffb4.usb: DWC OTG HCD HUB STATUS DATA: Root port status changed [ 133.506257] dwc2 ffb4.usb: port_connect_status_change: 0 [ 133.512065] dwc2
Re: [PATCH v3] usb: dwc2: add bus suspend/resume for dwc2
Hi Paul, I think you need this patch to fix the problem: usb: dwc2: resume root hub when device detect with suspend state https://patchwork.kernel.org/patch/5325111/ Thanks, - Kever On 01/06/2015 09:23 AM, Paul Zimmerman wrote: From: Kever Yang [mailto:kever.y...@rock-chips.com] Sent: Wednesday, November 12, 2014 4:42 PM On 11/13/2014 07:22 AM, Doug Anderson wrote: Kever, On Mon, Nov 10, 2014 at 5:09 AM, Kever Yang kever.y...@rock-chips.com wrote: Hcd controller needs bus_suspend/resume, dwc2 controller make root hub generate suspend/resume signal with hprt0 register when work in host mode. After the root hub enter suspend, we can make controller enter low power state with PCGCTL register. We also update the lx_state for hsotg state. This patch has tested on rk3288 with suspend/resume. Signed-off-by: Kever Yang kever.y...@rock-chips.com Acked-by: Paul Zimmerman pa...@synopsys.com --- Changes in v3: - remove CONFIG_PM macro for bus_suspend/resume - add PCGCTL operation for no device connect case Changes in v2: - update commit message - make dwc2 suspend/resume sourcecode work drivers/usb/dwc2/hcd.c | 88 +++--- 1 file changed, 77 insertions(+), 11 deletions(-) I would certainly appreciate confirmation, but my inclination is to NAK this change due to the fact that it regresses functionality. I haven't done any serious review of it, but I've been testing it and it appears to break hotplug. Said another way, I did this: 1. Without this patch, I booted with a USB stick in. It was detected. I unplugged it, waited 5 seconds, and then plugged it back in. The USB stick was redetcted. 2. With this patch, I did the same thing. The USB not redected after plugging it back in. With this patch, the dwc2 hcd/root hub will be auto suspend after device on port is disconnected, and it can't detect the device connect any more, I think that's the problem. I will figure out how to make dwc2 detect the device connect after auto suspend, or disable the auto suspend feature for the dwc2 hcd. Kever, This patch has made it into Linus' kernel as commit 0cf884e819e0, and it breaks disconnect/connect on at least the Altera SOCFPGA platform. I haven't been able to test it on any other platforms. You need to submit a patch to either fix this, or to only enable this feature for the Rock-chip platform. Otherwise the patch has to be reverted. -- To unsubscribe from this list: send the line unsubscribe linux-usb in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
RE: [PATCH v3] usb: dwc2: add bus suspend/resume for dwc2
From: Kever Yang [mailto:kever.y...@rock-chips.com]
Sent: Wednesday, November 12, 2014 4:42 PM
On 11/13/2014 07:22 AM, Doug Anderson wrote:
Kever,
On Mon, Nov 10, 2014 at 5:09 AM, Kever Yang kever.y...@rock-chips.com
wrote:
Hcd controller needs bus_suspend/resume, dwc2 controller make
root hub generate suspend/resume signal with hprt0 register
when work in host mode.
After the root hub enter suspend, we can make controller enter
low power state with PCGCTL register.
We also update the lx_state for hsotg state.
This patch has tested on rk3288 with suspend/resume.
Signed-off-by: Kever Yang kever.y...@rock-chips.com
Acked-by: Paul Zimmerman pa...@synopsys.com
---
Changes in v3:
- remove CONFIG_PM macro for bus_suspend/resume
- add PCGCTL operation for no device connect case
Changes in v2:
- update commit message
- make dwc2 suspend/resume sourcecode work
drivers/usb/dwc2/hcd.c | 88
+++---
1 file changed, 77 insertions(+), 11 deletions(-)
I would certainly appreciate confirmation, but my inclination is to
NAK this change due to the fact that it regresses functionality. I
haven't done any serious review of it, but I've been testing it and it
appears to break hotplug.
Said another way, I did this:
1. Without this patch, I booted with a USB stick in. It was detected.
I unplugged it, waited 5 seconds, and then plugged it back in. The
USB stick was redetcted.
2. With this patch, I did the same thing. The USB not redected after
plugging it back in.
With this patch, the dwc2 hcd/root hub will be auto suspend after device
on port is disconnected, and it can't detect the device connect any more,
I think that's the problem.
I will figure out how to make dwc2 detect the device connect after auto
suspend,
or disable the auto suspend feature for the dwc2 hcd.
Kever,
This patch has made it into Linus' kernel as commit 0cf884e819e0, and
it breaks disconnect/connect on at least the Altera SOCFPGA platform.
I haven't been able to test it on any other platforms.
You need to submit a patch to either fix this, or to only enable this
feature for the Rock-chip platform. Otherwise the patch has to be
reverted.
--
Paul
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RE: [PATCH v3] usb: dwc2: add bus suspend/resume for dwc2
From: Kever Yang [mailto:kever.y...@rock-chips.com] Sent: Monday, January 05, 2015 5:42 PM Hi Paul, I think you need this patch to fix the problem: usb: dwc2: resume root hub when device detect with suspend state https://patchwork.kernel.org/patch/5325111/ Thanks, - Kever On 01/06/2015 09:23 AM, Paul Zimmerman wrote: From: Kever Yang [mailto:kever.y...@rock-chips.com] Sent: Wednesday, November 12, 2014 4:42 PM On 11/13/2014 07:22 AM, Doug Anderson wrote: Kever, On Mon, Nov 10, 2014 at 5:09 AM, Kever Yang kever.y...@rock-chips.com wrote: Hcd controller needs bus_suspend/resume, dwc2 controller make root hub generate suspend/resume signal with hprt0 register when work in host mode. After the root hub enter suspend, we can make controller enter low power state with PCGCTL register. We also update the lx_state for hsotg state. This patch has tested on rk3288 with suspend/resume. Signed-off-by: Kever Yang kever.y...@rock-chips.com Acked-by: Paul Zimmerman pa...@synopsys.com --- Changes in v3: - remove CONFIG_PM macro for bus_suspend/resume - add PCGCTL operation for no device connect case Changes in v2: - update commit message - make dwc2 suspend/resume sourcecode work drivers/usb/dwc2/hcd.c | 88 +++--- 1 file changed, 77 insertions(+), 11 deletions(-) I would certainly appreciate confirmation, but my inclination is to NAK this change due to the fact that it regresses functionality. I haven't done any serious review of it, but I've been testing it and it appears to break hotplug. Said another way, I did this: 1. Without this patch, I booted with a USB stick in. It was detected. I unplugged it, waited 5 seconds, and then plugged it back in. The USB stick was redetcted. 2. With this patch, I did the same thing. The USB not redected after plugging it back in. With this patch, the dwc2 hcd/root hub will be auto suspend after device on port is disconnected, and it can't detect the device connect any more, I think that's the problem. I will figure out how to make dwc2 detect the device connect after auto suspend, or disable the auto suspend feature for the dwc2 hcd. Kever, This patch has made it into Linus' kernel as commit 0cf884e819e0, and it breaks disconnect/connect on at least the Altera SOCFPGA platform. I haven't been able to test it on any other platforms. You need to submit a patch to either fix this, or to only enable this feature for the Rock-chip platform. Otherwise the patch has to be reverted. Unfortunately, after applying that patch there is another problem. If I connect a device that causes an overcurrent condition to the root port, then the port is dead after that. No further devices are detected until after I reboot. I tried adding another call to usb_hcd_resume_root_hub() in the if (hprt0 HPRT0_OVRCURRCHG) branch, but then an overcurrent condition causes a continuous stream of these messages: [ 133.348776] dwc2 ffb4.usb: GetPortStatus wIndex=0x0001 flags=0x0022 [ 133.355717] dwc2 ffb4.usb: Overcurrent change detected [ 133.361179] dwc2 ffb4.usb: HPRT0: 0x0002 [ 133.365960] dwc2 ffb4.usb: port_status=0008 [ 133.373236] hub 1-0:1.0: state 7 ports 1 chg evt [ 133.380038] hub 1-0:1.0: hub_suspend [ 133.384237] usb usb1: bus auto-suspend, wakeup 1 [ 133.393631] dwc2 ffb4.usb: DWC OTG HCD HUB STATUS DATA: Root port status changed [ 133.401341] dwc2 ffb4.usb: port_connect_status_change: 0 [ 133.407157] dwc2 ffb4.usb: port_reset_change: 0 [ 133.412186] dwc2 ffb4.usb: port_enable_change: 0 [ 133.417310] dwc2 ffb4.usb: port_suspend_change: 0 [ 133.422519] dwc2 ffb4.usb: port_over_current_change: 1 [ 133.428154] usb usb1: suspend raced with wakeup event [ 133.433191] usb usb1: usb auto-resume [ 133.441522] hub 1-0:1.0: hub_resume [ 133.455505] dwc2 ffb4.usb: GetPortStatus wIndex=0x0001 flags=0x0022 [ 133.462443] dwc2 ffb4.usb: Overcurrent change detected [ 133.467907] dwc2 ffb4.usb: HPRT0: 0x0002 [ 133.472684] dwc2 ffb4.usb: port_status=0008 [ 133.480088] hub 1-0:1.0: state 7 ports 1 chg evt [ 133.485578] hub 1-0:1.0: hub_suspend [ 133.489157] usb usb1: bus auto-suspend, wakeup 1 [ 133.493768] dwc2 ffb4.usb: _dwc2_hcd_suspend() [ 133.498540] dwc2 ffb4.usb: DWC OTG HCD HUB STATUS DATA: Root port status changed [ 133.506257] dwc2 ffb4.usb: port_connect_status_change: 0 [ 133.512065] dwc2 ffb4.usb: port_reset_change: 0 [ 133.517102] dwc2 ffb4.usb: port_enable_change: 0 [ 133.522218] dwc2 ffb4.usb: port_suspend_change: 0 [ 133.527428] dwc2 ffb4.usb: port_over_current_change: 1 [ 133.533069] usb usb1: suspend raced with wakeup event [ 133.538098] usb usb1: usb auto-resume [ 133.546439] hub 1-0:1.0: hub_resume Any ideas? -- Paul
Re: [PATCH v3] usb: dwc2: add bus suspend/resume for dwc2
On 11/14/2014 11:55 PM, Alan Stern wrote: On Thu, 13 Nov 2014, Julius Werner wrote: Another thing might be that the port connect interrupt does not correctly resume the root hub. I don't really know many details about how that works, and it seems pretty complicated. But I can see that all other HCDs seem to call usb_hcd_resume_root_hub() from their interrupt handlers, which we don't. There's also a That's how a root hub sends a wakeup request to the kernel. The controller issues an interrupt, and when the HCD's interrupt handler sees that the root hub is suspended, it calls usb_hcd_resume_root_hub() instead of trying to query the hardware (because in general you _can't_ query the hardware while it's in a low-power state). Thanks Alan and Julius, just like what you have mentioned, the dwc2 miss the usb_hcd_resume_root_hub() when root hub is suspended and device connect detected. I have send another patch for that, hope it did the right thing. - Kever -- To unsubscribe from this list: send the line unsubscribe linux-usb in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH v3] usb: dwc2: add bus suspend/resume for dwc2
On Thu, 13 Nov 2014, Julius Werner wrote: Another thing might be that the port connect interrupt does not correctly resume the root hub. I don't really know many details about how that works, and it seems pretty complicated. But I can see that all other HCDs seem to call usb_hcd_resume_root_hub() from their interrupt handlers, which we don't. There's also a That's how a root hub sends a wakeup request to the kernel. The controller issues an interrupt, and when the HCD's interrupt handler sees that the root hub is suspended, it calls usb_hcd_resume_root_hub() instead of trying to query the hardware (because in general you _can't_ query the hardware while it's in a low-power state). usb_hcd_start_port_resume() in EHCI which I'm not familiar with, that seems to have been added recently. usb_hcd_start_port_resume() and usb_hcd_end_port_resume() were added in order to fix a race. We want to avoid suspending a root hub if a downstream suspended device is currently being resumed. The HCD is supposed to call these two routines when it begins and ends resume signalling on any of its ports. This will prevent the core from suspending the root hub while the port resume is in progress. And finally, it seems that all normal host controllers (UHCI/OHCI/EHCI/XHCI) now do the usb_hcd-uses_new_polling thing (where you're supposed to call hcd_poll_rh_status() from the HCD code)... the old polling code still seems to be in place, but without any relevant driver using I wouldn't be so sure if it's still functional. It is functional. The difference between the old and new polling schemes isn't all that big. In the old scheme, the core polls for root hub status changes every 250 ms. With the new scheme, the core doesn't poll -- it relies on the HCD to call usb_hcd_poll_rh_status() whenever there's a status-change interrupt. There's also a flag the HCD can set to ask for polling even if it uses the new scheme. This helps in situations where the root-hub status-change interrupts aren't reliable (for example, if they are edge-triggered rather than level-triggered). +Alan who should know HCD/core interactions much better and might have some ideas what the DWC2 driver is still missing right now. I know essentially zero about the DWC2 driver. But I'm happy to help by explaining how the core mechanisms are intended to be used. Alan Stern -- To unsubscribe from this list: send the line unsubscribe linux-usb in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
RE: [PATCH v3] usb: dwc2: add bus suspend/resume for dwc2
From: jwer...@google.com [mailto:jwer...@google.com] On Behalf Of Julius
Werner
Sent: Thursday, November 13, 2014 8:50 PM
I will figure out how to make dwc2 detect the device connect after auto
suspend,
or disable the auto suspend feature for the dwc2 hcd.
I think auto-suspend of the root hub device (which is what calls
bus_suspend, but is not the host controller device itself) is expected
to always happen and not really meant to be disabled. I'm surprised
that the controller would fail to come back up, though. Does removing
the PCGCTL part make it work? That's the only thing I can think of
(but then again the function should immediately return if the port is
not in L0, so if there is nothing plugged in the suspend shouldn't
really do anything).
Hi guys,
I don't have any experience with suspend/resume on the dwc2 controller
I'm afraid. One suggestion would be to look at our Synopsys vendor
driver to see how it is handled there.
That driver is part of the Raspberry Pi upstream kernel, which you
can find at https://github.com/raspberrypi/linux. The driver is
under drivers/usb/host/dwc_otg.
In particular, in dwc_otg_cil_intr.c there is a function named
dwc_otg_handle_wakeup_detected_intr() which might be of interest.
Unfortunately, that driver code is rather convoluted, so it may be
difficult to figure out exactly what the driver is doing.
--
Paul
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Re: [PATCH v3] usb: dwc2: add bus suspend/resume for dwc2
I will figure out how to make dwc2 detect the device connect after auto suspend, or disable the auto suspend feature for the dwc2 hcd. I think auto-suspend of the root hub device (which is what calls bus_suspend, but is not the host controller device itself) is expected to always happen and not really meant to be disabled. I'm surprised that the controller would fail to come back up, though. Does removing the PCGCTL part make it work? That's the only thing I can think of (but then again the function should immediately return if the port is not in L0, so if there is nothing plugged in the suspend shouldn't really do anything). Another thing might be that the port connect interrupt does not correctly resume the root hub. I don't really know many details about how that works, and it seems pretty complicated. But I can see that all other HCDs seem to call usb_hcd_resume_root_hub() from their interrupt handlers, which we don't. There's also a usb_hcd_start_port_resume() in EHCI which I'm not familiar with, that seems to have been added recently. And finally, it seems that all normal host controllers (UHCI/OHCI/EHCI/XHCI) now do the usb_hcd-uses_new_polling thing (where you're supposed to call hcd_poll_rh_status() from the HCD code)... the old polling code still seems to be in place, but without any relevant driver using I wouldn't be so sure if it's still functional. +Alan who should know HCD/core interactions much better and might have some ideas what the DWC2 driver is still missing right now. -- To unsubscribe from this list: send the line unsubscribe linux-usb in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH v3] usb: dwc2: add bus suspend/resume for dwc2
Kever, On Mon, Nov 10, 2014 at 5:09 AM, Kever Yang kever.y...@rock-chips.com wrote: Hcd controller needs bus_suspend/resume, dwc2 controller make root hub generate suspend/resume signal with hprt0 register when work in host mode. After the root hub enter suspend, we can make controller enter low power state with PCGCTL register. We also update the lx_state for hsotg state. This patch has tested on rk3288 with suspend/resume. Signed-off-by: Kever Yang kever.y...@rock-chips.com Acked-by: Paul Zimmerman pa...@synopsys.com --- Changes in v3: - remove CONFIG_PM macro for bus_suspend/resume - add PCGCTL operation for no device connect case Changes in v2: - update commit message - make dwc2 suspend/resume sourcecode work drivers/usb/dwc2/hcd.c | 88 +++--- 1 file changed, 77 insertions(+), 11 deletions(-) I would certainly appreciate confirmation, but my inclination is to NAK this change due to the fact that it regresses functionality. I haven't done any serious review of it, but I've been testing it and it appears to break hotplug. Said another way, I did this: 1. Without this patch, I booted with a USB stick in. It was detected. I unplugged it, waited 5 seconds, and then plugged it back in. The USB stick was redetcted. 2. With this patch, I did the same thing. The USB not redected after plugging it back in. -Doug -- To unsubscribe from this list: send the line unsubscribe linux-usb in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: [PATCH v3] usb: dwc2: add bus suspend/resume for dwc2
Doug, On 11/13/2014 07:22 AM, Doug Anderson wrote: Kever, On Mon, Nov 10, 2014 at 5:09 AM, Kever Yang kever.y...@rock-chips.com wrote: Hcd controller needs bus_suspend/resume, dwc2 controller make root hub generate suspend/resume signal with hprt0 register when work in host mode. After the root hub enter suspend, we can make controller enter low power state with PCGCTL register. We also update the lx_state for hsotg state. This patch has tested on rk3288 with suspend/resume. Signed-off-by: Kever Yang kever.y...@rock-chips.com Acked-by: Paul Zimmerman pa...@synopsys.com --- Changes in v3: - remove CONFIG_PM macro for bus_suspend/resume - add PCGCTL operation for no device connect case Changes in v2: - update commit message - make dwc2 suspend/resume sourcecode work drivers/usb/dwc2/hcd.c | 88 +++--- 1 file changed, 77 insertions(+), 11 deletions(-) I would certainly appreciate confirmation, but my inclination is to NAK this change due to the fact that it regresses functionality. I haven't done any serious review of it, but I've been testing it and it appears to break hotplug. Said another way, I did this: 1. Without this patch, I booted with a USB stick in. It was detected. I unplugged it, waited 5 seconds, and then plugged it back in. The USB stick was redetcted. 2. With this patch, I did the same thing. The USB not redected after plugging it back in. With this patch, the dwc2 hcd/root hub will be auto suspend after device on port is disconnected, and it can't detect the device connect any more, I think that's the problem. I will figure out how to make dwc2 detect the device connect after auto suspend, or disable the auto suspend feature for the dwc2 hcd. - Kever -- To unsubscribe from this list: send the line unsubscribe linux-usb in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
