Re: [PATCH v13 2/6] usb: dwc3: core: Host wake up support from system suspend

From: Matthias Kaehlcke
Date: Mon Apr 11 2022 - 16:54:28 EST

On Tue, Apr 12, 2022 at 12:46:50AM +0530, Sandeep Maheswaram wrote:
> During suspend read the status of all port and set hs phy mode
> based on current speed. Use this hs phy mode to configure wakeup
> interrupts in qcom glue driver.
>
> Check wakep-source property for dwc3 core node to set the

s/wakep/wakeup/

> wakeup capability. Drop the device_init_wakeup call from
> runtime suspend and resume.
>
> Also check during suspend if any wakeup capable devices are
> connected to the controller (directly or through hubs), if there
> are none set a flag to indicate that the PHY is powered
> down during suspend.
>
> Signed-off-by: Sandeep Maheswaram <quic_c_sanm@xxxxxxxxxxx>
> ---

A per-patch change log would be really helpful for reviewers, even
if it doesn't include older versions.

> drivers/usb/dwc3/core.c | 33 ++++++++++++++++++++-------------
> drivers/usb/dwc3/core.h | 4 ++++
> drivers/usb/dwc3/host.c | 25 +++++++++++++++++++++++++
> 3 files changed, 49 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> index 1170b80..effaa43 100644
> --- a/drivers/usb/dwc3/core.c
> +++ b/drivers/usb/dwc3/core.c
> @@ -32,6 +32,7 @@
> #include <linux/usb/gadget.h>
> #include <linux/usb/of.h>
> #include <linux/usb/otg.h>
> +#include <linux/usb/hcd.h>
>
> #include "core.h"
> #include "gadget.h"
> @@ -1723,6 +1724,7 @@ static int dwc3_probe(struct platform_device *pdev)
>
> platform_set_drvdata(pdev, dwc);
> dwc3_cache_hwparams(dwc);
> + device_init_wakeup(&pdev->dev, of_property_read_bool(dev->of_node, "wakeup-source"));
>
> spin_lock_init(&dwc->lock);
> mutex_init(&dwc->mutex);
> @@ -1865,6 +1867,7 @@ static int dwc3_suspend_common(struct dwc3 *dwc, pm_message_t msg)
> {
> unsigned long flags;
> u32 reg;
> + struct usb_hcd *hcd = platform_get_drvdata(dwc->xhci);
>
> switch (dwc->current_dr_role) {
> case DWC3_GCTL_PRTCAP_DEVICE:
> @@ -1877,10 +1880,7 @@ static int dwc3_suspend_common(struct dwc3 *dwc, pm_message_t msg)
> dwc3_core_exit(dwc);
> break;
> case DWC3_GCTL_PRTCAP_HOST:
> - if (!PMSG_IS_AUTO(msg)) {
> - dwc3_core_exit(dwc);
> - break;
> - }
> + dwc3_check_phy_speed_mode(dwc);
>
> /* Let controller to suspend HSPHY before PHY driver suspends */
> if (dwc->dis_u2_susphy_quirk ||
> @@ -1896,6 +1896,16 @@ static int dwc3_suspend_common(struct dwc3 *dwc, pm_message_t msg)
>
> phy_pm_runtime_put_sync(dwc->usb2_generic_phy);
> phy_pm_runtime_put_sync(dwc->usb3_generic_phy);
> +
> + if (!PMSG_IS_AUTO(msg)) {
> + if (device_may_wakeup(dwc->dev) &&
> + usb_wakeup_enabled_descendants(hcd->self.root_hub)) {

You did not answer my question on v12, reposting it:

Did you ever try whether you could use device_children_wakeup_capable() from
[1] instead of usb_wakeup_enabled_descendants()?

[1] https://patchwork.kernel.org/project/linux-usb/patch/1635753224-23975-2-git-send-email-quic_c_sanm@xxxxxxxxxxx/#24566065

> + dwc->phy_power_off = false;
> + } else {
> + dwc->phy_power_off = true;
> + dwc3_core_exit(dwc);
> + }
> + }
> break;
> case DWC3_GCTL_PRTCAP_OTG:
> /* do nothing during runtime_suspend */
> @@ -1939,11 +1949,12 @@ static int dwc3_resume_common(struct dwc3 *dwc, pm_message_t msg)
> break;
> case DWC3_GCTL_PRTCAP_HOST:
> if (!PMSG_IS_AUTO(msg)) {
> - ret = dwc3_core_init_for_resume(dwc);
> - if (ret)
> - return ret;
> - dwc3_set_prtcap(dwc, DWC3_GCTL_PRTCAP_HOST);
> - break;
> + if (dwc->phy_power_off) {
> + ret = dwc3_core_init_for_resume(dwc);
> + if (ret)
> + return ret;
> + dwc3_set_prtcap(dwc, DWC3_GCTL_PRTCAP_HOST);
> + }
> }
> /* Restore GUSB2PHYCFG bits that were modified in suspend */
> reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0));
> @@ -2015,8 +2026,6 @@ static int dwc3_runtime_suspend(struct device *dev)
> if (ret)
> return ret;
>
> - device_init_wakeup(dev, true);
> -
> return 0;
> }
>
> @@ -2025,8 +2034,6 @@ static int dwc3_runtime_resume(struct device *dev)
> struct dwc3 *dwc = dev_get_drvdata(dev);
> int ret;
>
> - device_init_wakeup(dev, false);
> -
> ret = dwc3_resume_common(dwc, PMSG_AUTO_RESUME);
> if (ret)
> return ret;
> diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
> index 5c9d467..6a5845f 100644
> --- a/drivers/usb/dwc3/core.h
> +++ b/drivers/usb/dwc3/core.h
> @@ -1154,6 +1154,9 @@ struct dwc3 {
>
> bool phys_ready;
>
> + unsigned int hs_phy_mode;
> + bool phy_power_off;
> +
> struct ulpi *ulpi;
> bool ulpi_ready;
>
> @@ -1537,6 +1540,7 @@ int dwc3_core_soft_reset(struct dwc3 *dwc);
> #if IS_ENABLED(CONFIG_USB_DWC3_HOST) || IS_ENABLED(CONFIG_USB_DWC3_DUAL_ROLE)
> int dwc3_host_init(struct dwc3 *dwc);
> void dwc3_host_exit(struct dwc3 *dwc);
> +void dwc3_check_phy_speed_mode(struct dwc3 *dwc);
> #else
> static inline int dwc3_host_init(struct dwc3 *dwc)
> { return 0; }
> diff --git a/drivers/usb/dwc3/host.c b/drivers/usb/dwc3/host.c
> index eda8719..7f22675 100644
> --- a/drivers/usb/dwc3/host.c
> +++ b/drivers/usb/dwc3/host.c
> @@ -13,6 +13,7 @@
> #include <linux/platform_device.h>
>
> #include "core.h"
> +#include "../host/xhci.h"
>
> static void dwc3_host_fill_xhci_irq_res(struct dwc3 *dwc,
> int irq, char *name)
> @@ -138,3 +139,27 @@ void dwc3_host_exit(struct dwc3 *dwc)
> {
> platform_device_unregister(dwc->xhci);
> }
> +
> +void dwc3_check_phy_speed_mode(struct dwc3 *dwc)
> +{
> +

delete empty line

> + int i, num_ports;
> + u32 reg;
> + struct usb_hcd *hcd = platform_get_drvdata(dwc->xhci);
> + struct xhci_hcd *xhci_hcd = hcd_to_xhci(hcd);
> +
> + dwc->hs_phy_mode = 0;
> +
> + reg = readl(&xhci_hcd->cap_regs->hcs_params1);
> +
> + num_ports = HCS_MAX_PORTS(reg);
> + for (i = 0; i < num_ports; i++) {
> + reg = readl(&xhci_hcd->op_regs->port_status_base + i * NUM_PORT_REGS);
> + if (reg & PORT_PE) {
> + if (DEV_HIGHSPEED(reg) || DEV_FULLSPEED(reg))
> + dwc->hs_phy_mode |= PHY_MODE_USB_HOST_HS;
> + else if (DEV_LOWSPEED(reg))
> + dwc->hs_phy_mode |= PHY_MODE_USB_HOST_LS;
> + }
> + }
> +}
> --
> 2.7.4
>