On 22/03/18 10:10, Chunfeng Yun wrote: > Hi, > On Wed, 2018-03-21 at 13:30 +0200, Roger Quadros wrote: >> Martin, >> >> On 21/03/18 00:01, Martin Blumenstingl wrote: >>> Hi Roger, Hi Chunfeng, >>> >>> On Tue, Mar 20, 2018 at 1:04 PM, Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx> wrote: >>>> Hi Martin & Roger: >>>> >>>> On Mon, 2018-03-19 at 17:12 +0100, Martin Blumenstingl wrote: >>>>> Hi Roger, >>>>> >>>>> On Mon, Mar 19, 2018 at 9:49 AM, Roger Quadros <rogerq@xxxxxx> wrote: >>>>>> Hi, >>>>>> >>>>>> On 19/03/18 00:29, Martin Blumenstingl wrote: >>>>>>> Hi Roger, >>>>>>> >>>>>>> On Fri, Mar 16, 2018 at 3:32 PM, Roger Quadros <rogerq@xxxxxx> wrote: >>>>>>>> +some TI folks >>>>>>>> >>>>>>>> Hi Martin, >>>>>>>> >>>>>>>> On 18/02/18 20:44, Martin Blumenstingl wrote: >>>>>>>>> Many SoC platforms have separate devices for the USB PHY which are >>>>>>>>> registered through the generic PHY framework. These PHYs have to be >>>>>>>>> enabled to make the USB controller actually work. They also have to be >>>>>>>>> disabled again on shutdown/suspend. >>>>>>>>> >>>>>>>>> Currently (at least) the following HCI platform drivers are using custom >>>>>>>>> code to obtain all PHYs via devicetree for the roothub/controller and >>>>>>>>> disable/enable them when required: >>>>>>>>> - ehci-platform.c has ehci_platform_power_{on,off} >>>>>>>>> - xhci-mtk.c has xhci_mtk_phy_{init,exit,power_on,power_off} >>>>>>>>> - ohci-platform.c has ohci_platform_power_{on,off} >>>>>>>>> >>>>>>>>> With this new wrapper the USB PHYs can be specified directly in the >>>>>>>>> USB controller's devicetree node (just like on the drivers listed >>>>>>>>> above). This allows SoCs like the Amlogic Meson GXL family to operate >>>>>>>>> correctly once this is wired up correctly. These SoCs use a dwc3 >>>>>>>>> controller and require all USB PHYs to be initialized (if one of the USB >>>>>>>>> PHYs it not initialized then none of USB port works at all). >>>>>>>>> >>>>>>>>> Signed-off-by: Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx> >>>>>>>>> Tested-by: Yixun Lan <yixun.lan@xxxxxxxxxxx> >>>>>>>>> Cc: Neil Armstrong <narmstrong@xxxxxxxxxxxx> >>>>>>>>> Cc: Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx> >>>>>>>> >>>>>>>> This patch is breaking low power cases on TI SoCs when USB is in host mode. >>>>>>>> I'll explain why below. >>>>>>> based on your explanation and reading the TI PHY drivers I am assuming >>>>>>> that the affected SoCs are using the "phy-omap-usb2" driver >>>>>>> >>>>>> yes and phy-ti-pipe3 as well i.e. "ti,phy-usb3" and "ti,omap-usb3" >>>>> I missed that, thanks >>>>> >>>>>>>>> --- >>>>>>>>> drivers/usb/core/Makefile | 2 +- >>>>>>>>> drivers/usb/core/phy.c | 158 ++++++++++++++++++++++++++++++++++++++++++++++ >>>>>>>>> drivers/usb/core/phy.h | 7 ++ >>>>>>>>> 3 files changed, 166 insertions(+), 1 deletion(-) >>>>>>>>> create mode 100644 drivers/usb/core/phy.c >>>>>>>>> create mode 100644 drivers/usb/core/phy.h >>>>>>>>> >>>>>>>>> diff --git a/drivers/usb/core/Makefile b/drivers/usb/core/Makefile >>>>>>>>> index 92c9cefb4317..18e874b0441e 100644 >>>>>>>>> --- a/drivers/usb/core/Makefile >>>>>>>>> +++ b/drivers/usb/core/Makefile >>>>>>>>> @@ -6,7 +6,7 @@ >>>>>>>>> usbcore-y := usb.o hub.o hcd.o urb.o message.o driver.o >>>>>>>>> usbcore-y += config.o file.o buffer.o sysfs.o endpoint.o >>>>>>>>> usbcore-y += devio.o notify.o generic.o quirks.o devices.o >>>>>>>>> -usbcore-y += port.o >>>>>>>>> +usbcore-y += phy.o port.o >>>>>>>>> >>>>>>>>> usbcore-$(CONFIG_OF) += of.o >>>>>>>>> usbcore-$(CONFIG_USB_PCI) += hcd-pci.o >>>>>>>>> diff --git a/drivers/usb/core/phy.c b/drivers/usb/core/phy.c >>>>>>>>> new file mode 100644 >>>>>>>>> index 000000000000..09b7c43c0ea4 >>>>>>>>> --- /dev/null >>>>>>>>> +++ b/drivers/usb/core/phy.c >>>>>>>>> @@ -0,0 +1,158 @@ >>>>>>>>> +// SPDX-License-Identifier: GPL-2.0+ >>>>>>>>> +/* >>>>>>>>> + * A wrapper for multiple PHYs which passes all phy_* function calls to >>>>>>>>> + * multiple (actual) PHY devices. This is comes handy when initializing >>>>>>>>> + * all PHYs on a HCD and to keep them all in the same state. >>>>>>>>> + * >>>>>>>>> + * Copyright (C) 2018 Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx> >>>>>>>>> + */ >>>>>>>>> + >>>>>>>>> +#include <linux/device.h> >>>>>>>>> +#include <linux/list.h> >>>>>>>>> +#include <linux/phy/phy.h> >>>>>>>>> +#include <linux/of.h> >>>>>>>>> + >>>>>>>>> +#include "phy.h" >>>>>>>>> + >>>>>>>>> +struct usb_phy_roothub { >>>>>>>>> + struct phy *phy; >>>>>>>>> + struct list_head list; >>>>>>>>> +}; >>>>>>>>> + >>>>>>>>> +static struct usb_phy_roothub *usb_phy_roothub_alloc(struct device *dev) >>>>>>>>> +{ >>>>>>>>> + struct usb_phy_roothub *roothub_entry; >>>>>>>>> + >>>>>>>>> + roothub_entry = devm_kzalloc(dev, sizeof(*roothub_entry), GFP_KERNEL); >>>>>>>>> + if (!roothub_entry) >>>>>>>>> + return ERR_PTR(-ENOMEM); >>>>>>>>> + >>>>>>>>> + INIT_LIST_HEAD(&roothub_entry->list); >>>>>>>>> + >>>>>>>>> + return roothub_entry; >>>>>>>>> +} >>>>>>>>> + >>>>>>>>> +static int usb_phy_roothub_add_phy(struct device *dev, int index, >>>>>>>>> + struct list_head *list) >>>>>>>>> +{ >>>>>>>>> + struct usb_phy_roothub *roothub_entry; >>>>>>>>> + struct phy *phy = devm_of_phy_get_by_index(dev, dev->of_node, index); >>>>>>>>> + >>>>>>>>> + if (IS_ERR_OR_NULL(phy)) { >>>>>>>>> + if (!phy || PTR_ERR(phy) == -ENODEV) >>>>>>>>> + return 0; >>>>>>>>> + else >>>>>>>>> + return PTR_ERR(phy); >>>>>>>>> + } >>>>>>>>> + >>>>>>>>> + roothub_entry = usb_phy_roothub_alloc(dev); >>>>>>>>> + if (IS_ERR(roothub_entry)) >>>>>>>>> + return PTR_ERR(roothub_entry); >>>>>>>>> + >>>>>>>>> + roothub_entry->phy = phy; >>>>>>>>> + >>>>>>>>> + list_add_tail(&roothub_entry->list, list); >>>>>>>>> + >>>>>>>>> + return 0; >>>>>>>>> +} >>>>>>>>> + >>>>>>>>> +struct usb_phy_roothub *usb_phy_roothub_init(struct device *dev) >>>>>>>>> +{ >>>>>>>>> + struct usb_phy_roothub *phy_roothub; >>>>>>>>> + struct usb_phy_roothub *roothub_entry; >>>>>>>>> + struct list_head *head; >>>>>>>>> + int i, num_phys, err; >>>>>>>>> + >>>>>>>>> + num_phys = of_count_phandle_with_args(dev->of_node, "phys", >>>>>>>>> + "#phy-cells"); >>>>>>>>> + if (num_phys <= 0) >>>>>>>>> + return NULL; >>>>>>>>> + >>>>>>>>> + phy_roothub = usb_phy_roothub_alloc(dev); >>>>>>>>> + if (IS_ERR(phy_roothub)) >>>>>>>>> + return phy_roothub; >>>>>>>>> + >>>>>>>>> + for (i = 0; i < num_phys; i++) { >>>>>>>>> + err = usb_phy_roothub_add_phy(dev, i, &phy_roothub->list); >>>>>>>>> + if (err) >>>>>>>>> + goto err_out; >>>>>>>>> + } >>>>>>>>> + >>>>>>>>> + head = &phy_roothub->list; >>>>>>>>> + >>>>>>>>> + list_for_each_entry(roothub_entry, head, list) { >>>>>>>>> + err = phy_init(roothub_entry->phy); >>>>>>>> >>>>>>>> The phy_init() function actually enables the PHY clocks. >>>>>>>> It should be moved to the usb_phy_roothub_exit() routine just before calling phy_power_on(). >>>>>>> do you mean that phy_init should be moved to usb_phy_roothub_power_on >>>>>>> (just before phy_power_on is called within usb_phy_roothub_power_on)? >>>>>>> >>>>>> >>>>>> Yes. >>>>>> >>>>>>> an earlier version of my patch did exactly this, but it caused >>>>>>> problems during a suspend/resume cycle on Mediatek devices >>>>>>> Chunfeng Yun reported that issue here [0], quote from that mail for >>>>>>> easier reading: >>>>>>> "In order to keep link state on mt8173, we just power off all phys(not >>>>>>> exit) when system enter suspend, then power on them again (needn't >>>>>>> init, otherwise device will be disconnected) when system resume, this >>>>>>> can avoid re-enumerating device." >>>>>>> >>>>>>>>> + if (err) >>>>>>>>> + goto err_exit_phys; >>>>>>>>> + } >>>>>>>>> + >>>>>>>>> + return phy_roothub; >>>>>>>>> + >>>>>>>>> +err_exit_phys: >>>>>>>>> + list_for_each_entry_continue_reverse(roothub_entry, head, list) >>>>>>>>> + phy_exit(roothub_entry->phy); >>>>>>>>> + >>>>>>>>> +err_out: >>>>>>>>> + return ERR_PTR(err); >>>>>>>>> +} >>>>>>>>> +EXPORT_SYMBOL_GPL(usb_phy_roothub_init); >>>>>>>>> + >>>>>>>>> +int usb_phy_roothub_exit(struct usb_phy_roothub *phy_roothub) >>>>>>>>> +{ >>>>>>>>> + struct usb_phy_roothub *roothub_entry; >>>>>>>>> + struct list_head *head; >>>>>>>>> + int err, ret = 0; >>>>>>>>> + >>>>>>>>> + if (!phy_roothub) >>>>>>>>> + return 0; >>>>>>>>> + >>>>>>>>> + head = &phy_roothub->list; >>>>>>>>> + >>>>>>>>> + list_for_each_entry(roothub_entry, head, list) { >>>>>>>>> + err = phy_exit(roothub_entry->phy); >>>>>>>>> + if (err) >>>>>>>>> + ret = ret; >>>>>>>>> + } >>>>>>>> >>>>>>>> phy_exit() should be moved to usb_phy_roothub_poweroff() just after calling phy_power_off(). >>>>>>> if I understood Chunfeng Yun correctly this will require >>>>>>> re-enumeration of the USB devices after a suspend/resume cycle on >>>>>>> Mediatek SoCs >>>>>>> >>>>>> >>>>>> OK. I suppose that there are 2 cases >>>>>> 1) Mediatek's case: USB controller context retained across suspend/resume. >>>>>> Remote wakeup probably required. >>>>>> No re-enumeration preferred after resume. phy_exit()/phy_init() must not be called >>>>>> during suspend/resume to keep PHY link active. >>>>> Documentation/devicetree/bindings/usb/mediatek,mtu3.txt indeed shows >>>>> that the parent of the USB controller can be marked as "wakeup-source" >>>>> >>>>>> 2) TI's case: low power important: USB context is lost, OK to re-enumerate. >>>>>> phy_exit()/phy_init() must be called during suspend/resume. >>>>> ACK >>>>> >>>>>>>> With that there is nothing else being done here. Shouldn't we be doing the equivalent of >>>>>>>> usb_phy_roothub_del_phy() and usb_phy_roothub_free() here? >>>>>>>> >>>>>>>>> + >>>>>>>>> + return ret; >>>>>>>>> +} >>>>>>>>> +EXPORT_SYMBOL_GPL(usb_phy_roothub_exit); >>>>>>>>> + >>>>>>>>> +int usb_phy_roothub_power_on(struct usb_phy_roothub *phy_roothub) >>>>>>>>> +{ >>>>>>>>> + struct usb_phy_roothub *roothub_entry; >>>>>>>>> + struct list_head *head; >>>>>>>>> + int err; >>>>>>>>> + >>>>>>>>> + if (!phy_roothub) >>>>>>>>> + return 0; >>>>>>>>> + >>>>>>>>> + head = &phy_roothub->list; >>>>>>>>> + >>>>>>>>> + list_for_each_entry(roothub_entry, head, list) { >>>>>>>>> + err = phy_power_on(roothub_entry->phy); >>>>>>>>> + if (err) >>>>>>>>> + goto err_out; >>>>>>>>> + } >>>>>>>>> + >>>>>>>>> + return 0; >>>>>>>>> + >>>>>>>>> +err_out: >>>>>>>>> + list_for_each_entry_continue_reverse(roothub_entry, head, list) >>>>>>>>> + phy_power_off(roothub_entry->phy); >>>>>>>>> + >>>>>>>>> + return err; >>>>>>>>> +} >>>>>>>>> +EXPORT_SYMBOL_GPL(usb_phy_roothub_power_on); >>>>>>>>> + >>>>>>>>> +void usb_phy_roothub_power_off(struct usb_phy_roothub *phy_roothub) >>>>>>>>> +{ >>>>>>>>> + struct usb_phy_roothub *roothub_entry; >>>>>>>>> + >>>>>>>>> + if (!phy_roothub) >>>>>>>>> + return; >>>>>>>>> + >>>>>>>>> + list_for_each_entry_reverse(roothub_entry, &phy_roothub->list, list) >>>>>>>>> + phy_power_off(roothub_entry->phy); >>>>>>>> >>>>>>>> Not doing the phy_exit() here leaves the clocks enabled on our SoC and >>>>>>>> we're no longer able to reach low power states on system suspend. >>>>>>> I'm not sure where this problem should be solved: >>>>>>> - set skip_phy_initialization in struct usb_hcd to 1 for the affected >>>>>>> TI platforms >>>>>> >>>>>> Many TI platforms are affected, omap5*, dra7*, am43* >>>>>> >>>>>>> - fix this in the usb_phy_roothub code >>>>>> >>>>>> I'd vote for fixing it in the usb_phy_roothub code. How? >>>>>> How about using the device_can_wakeup() to decide if we should call phy_exit()/init() or not? >>>>>> If the USB device can't wakeup the system there is no point in keeping it powered/clocked right? >>>>> @Chunfeng: can you confirm Roger's idea that we could call phy_exit if >>>>> the controller is *NOT* marked as "wakeup-source"? >>>>> I am also not sure if it would work, since the "wakeup-source" >>>>> property is defined on the USB controller's parent node in case of the >>>>> Mediatek MTU3 (Mediatek USB3.0 DRD) controller >>>>> >>>> Very sorry, I forgot that MTU3 & xHCI drivers always set them as wakeup >>>> devices by device_init_wakeup(dev, true),but not dependent on >>>> "wakeup-source" property, so maybe we can use device_can_wakeup() to >>>> decide whether call phy_exit()/init() or not. >>> the 64-bit Amlogic Meson GXL/GXM SoCs don't support suspend/resume >>> yet, so I cannot test this >>> based on this suggestion I threw up two patches which are *compile >>> tested only* based on Greg's usb-next branch >>> you can find them here: [0] (as well as attached to this mail) >>> >>> @Chunfeng: can you please test this on one of your Mediatek SoCs? >>> @Roger: can you please test this on a TI SoC? >>> >>> (apologies in advance if these patches don't work) >>> >>> please note that I won't have access to my computer until Saturday. >>> if these patches need to be rewritten/replaced/etc. then feel free to >>> send your own version to the list >> >> Had to do the following to build >> >> diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c >> index 6d4a419..2884607 100644 >> --- a/drivers/usb/core/hcd.c >> +++ b/drivers/usb/core/hcd.c >> @@ -2262,7 +2262,7 @@ int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg) >> hcd->state = HC_STATE_SUSPENDED; >> >> if (!PMSG_IS_AUTO(msg)) >> - usb_phy_roothub_suspend(hcd->phy_roothub); >> + usb_phy_roothub_suspend(&rhdev->dev, hcd->phy_roothub); > > Try to use hcd->self.controller instead of &rhdev->dev; Actually it should be hcd->self.sysdev. > >> >> /* Did we race with a root-hub wakeup event? */ >> if (rhdev->do_remote_wakeup) { >> @@ -2302,7 +2302,7 @@ int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg) >> } >> >> if (!PMSG_IS_AUTO(msg)) { >> - status = usb_phy_roothub_resume(hcd->phy_roothub); >> + status = usb_phy_roothub_resume(&rhdev->dev, hcd->phy_roothub); > ditto >> if (status) >> return status; >> } >> @@ -2344,7 +2344,7 @@ int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg) >> } >> } else { >> hcd->state = old_state; >> - usb_phy_roothub_suspend(hcd->phy_roothub); >> + usb_phy_roothub_suspend(&rhdev->dev, hcd->phy_roothub); > ditto >> dev_dbg(&rhdev->dev, "bus %s fail, err %d\n", >> "resume", status); >> if (status != -ESHUTDOWN) >> >> >> And the following to fix runtime issues >> >> diff --git a/drivers/usb/core/phy.c b/drivers/usb/core/phy.c >> index 2eca371..8598906 100644 >> --- a/drivers/usb/core/phy.c >> +++ b/drivers/usb/core/phy.c >> @@ -32,9 +32,9 @@ static int usb_phy_roothub_add_phy(struct device *dev, int index, >> return PTR_ERR(phy); >> } >> >> - roothub_entry = usb_phy_roothub_alloc(dev); >> - if (IS_ERR(roothub_entry)) >> - return PTR_ERR(roothub_entry); >> + roothub_entry = devm_kzalloc(dev, sizeof(*roothub_entry), GFP_KERNEL); >> + if (!roothub_entry) >> + return -ENOMEM; >> >> roothub_entry->phy = phy; >> >> @@ -162,7 +162,7 @@ int usb_phy_roothub_suspend(struct device *dev, >> usb_phy_roothub_power_off(phy_roothub); >> >> /* keep the PHYs initialized so the device can wake up the system */ >> - if (device_can_wakeup(dev)) >> + if (device_may_wakeup(dev)) > It's ok I had to additionally fix usb_phy_roothub_resume() from if (device_can_wakeup(dev)) to if (!device_may_wakeup(dev)) >> return 0; >> >> return usb_phy_roothub_exit(phy_roothub); >> >> >> Here are my obervations >> - if wakeup is disabled it works fine as expected, phy_exit() is called and I'm able to reach >> low power states. >> >> - if wakeup is enabled (/sys/bus/usb/device/usb2/power/wakeup), then hcd_bus_suspend() is never called >> and so phy_power_off won't be called either. >> >> This means that the device_may_wakeup() check is redundant. Sorry for suggesting this. > You maybe use a wrong device. Yes, after using the correct device I don't see the problem. Can you please try the below patch on top of the 2 Patches that Martin sent and the new patch you sent? Once you confirm it works for you I can send the 2 patches officially. diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c index 6d4a419..04cc453 100644 --- a/drivers/usb/core/hcd.c +++ b/drivers/usb/core/hcd.c @@ -2262,7 +2262,7 @@ int hcd_bus_suspend(struct usb_device *rhdev, pm_message_t msg) hcd->state = HC_STATE_SUSPENDED; if (!PMSG_IS_AUTO(msg)) - usb_phy_roothub_suspend(hcd->phy_roothub); + usb_phy_roothub_suspend(hcd->self.sysdev, hcd->phy_roothub); /* Did we race with a root-hub wakeup event? */ if (rhdev->do_remote_wakeup) { @@ -2302,7 +2302,7 @@ int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg) } if (!PMSG_IS_AUTO(msg)) { - status = usb_phy_roothub_resume(hcd->phy_roothub); + status = usb_phy_roothub_resume(hcd->self.sysdev, hcd->phy_roothub); if (status) return status; } @@ -2344,7 +2344,7 @@ int hcd_bus_resume(struct usb_device *rhdev, pm_message_t msg) } } else { hcd->state = old_state; - usb_phy_roothub_suspend(hcd->phy_roothub); + usb_phy_roothub_suspend(hcd->self.sysdev, hcd->phy_roothub); dev_dbg(&rhdev->dev, "bus %s fail, err %d\n", "resume", status); if (status != -ESHUTDOWN) diff --git a/drivers/usb/core/phy.c b/drivers/usb/core/phy.c index 2eca371..25fe729 100644 --- a/drivers/usb/core/phy.c +++ b/drivers/usb/core/phy.c @@ -32,9 +32,9 @@ static int usb_phy_roothub_add_phy(struct device *dev, int index, return PTR_ERR(phy); } - roothub_entry = usb_phy_roothub_alloc(dev); - if (IS_ERR(roothub_entry)) - return PTR_ERR(roothub_entry); + roothub_entry = devm_kzalloc(dev, sizeof(*roothub_entry), GFP_KERNEL); + if (!roothub_entry) + return -ENOMEM; roothub_entry->phy = phy; @@ -162,7 +162,7 @@ int usb_phy_roothub_suspend(struct device *dev, usb_phy_roothub_power_off(phy_roothub); /* keep the PHYs initialized so the device can wake up the system */ - if (device_can_wakeup(dev)) + if (device_may_wakeup(dev)) return 0; return usb_phy_roothub_exit(phy_roothub); @@ -175,7 +175,7 @@ int usb_phy_roothub_resume(struct device *dev, int err; /* if the device can't wake up the system _exit was called */ - if (device_can_wakeup(dev)) { + if (!device_may_wakeup(dev)) { err = usb_phy_roothub_init(phy_roothub); if (err) return err; -- cheers, -roger Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki. 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