From 1ccd114e35d885f2014330261fc413658ce056ca Mon Sep 17 00:00:00 2001 From: Roy Luo Date: Wed, 12 Mar 2025 22:34:34 +0000 Subject: [PATCH] UPSTREAM: usb: dwc3: core: Avoid redundant system suspend/resume callbacks dwc3 device suspend/resume callbacks were being triggered during system suspend and resume even if the device was already runtime-suspended. This is redundant for device mode because the suspend and resume routines are essentially identical for system PM and runtime PM. To prevent these unnecessary callbacks, indicate to the PM core that it can safely leave the device in runtime suspend if it's already runtime-suspended in device mode by returning a positive value in prepare() callback. This optimization only applies to devices without pinctrl, as pinctrl has distinct logic tied to system suspend/resume. Signed-off-by: Roy Luo Acked-by: Thinh Nguyen Link: https://lore.kernel.org/r/20250312223434.3071598-1-royluo@google.com Signed-off-by: Greg Kroah-Hartman Bug: 394262559 Change-Id: If119cf8569105fe2f0d7613e932bd0db24ef4e07 (cherry picked from commit 850e634006f453d57fffe86ca07da15713dea3b8) Signed-off-by: Roy Luo --- drivers/usb/dwc3/core.c | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-) diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c index a30643bd46f2..4e3845ec13bf 100644 --- a/drivers/usb/dwc3/core.c +++ b/drivers/usb/dwc3/core.c @@ -26,6 +26,7 @@ #include #include #include +#include #include #include @@ -2651,14 +2652,31 @@ static void dwc3_complete(struct device *dev) dwc3_writel(dwc->regs, DWC3_GUCTL3, reg); } } + +static int dwc3_prepare(struct device *dev) +{ + struct dwc3 *dwc = dev_get_drvdata(dev); + + /* + * Indicate to the PM core that it may safely leave the device in + * runtime suspend if runtime-suspended already in device mode. + */ + if (dwc->current_dr_role == DWC3_GCTL_PRTCAP_DEVICE && + pm_runtime_suspended(dev) && + !dev_pinctrl(dev)) + return 1; + + return 0; +} #else #define dwc3_complete NULL +#define dwc3_prepare NULL #endif /* CONFIG_PM_SLEEP */ static const struct dev_pm_ops dwc3_dev_pm_ops = { SET_SYSTEM_SLEEP_PM_OPS(dwc3_suspend, dwc3_resume) .complete = dwc3_complete, - + .prepare = dwc3_prepare, /* * Runtime suspend halts the controller on disconnection. It relies on * platforms with custom connection notification to start the controller