Since commit 6d735722063a ("usb: dwc3: core: Prevent phy suspend during init"), system suspend is broken on AM62 TI platforms.

Before that commit, both DWC3_GUSB3PIPECTL_SUSPHY and DWC3_GUSB2PHYCFG_SUSPHY bits (hence forth called 2 SUSPHY bits) were being set during core initialization and even during core re-initialization after a system suspend/resume.

These bits are required to be set for system suspend/resume to work correctly on AM62 platforms.

Since that commit, the 2 SUSPHY bits are not set for DEVICE/OTG mode if gadget driver is not loaded and started. For Host mode, the 2 SUSPHY bits are set before the first system suspend but get cleared at system resume during core re-init and are never set again.

This patch resovles these two issues by ensuring the 2 SUSPHY bits are set before system suspend and restored to the original state during system resume.

Cc: stable@vger.kernel.org # v6.9+ Fixes: 6d735722063a ("usb: dwc3: core: Prevent phy suspend during init") Link: https://lore.kernel.org/all/1519dbe7-73b6-4afc-bfe3-23f4f75d772f@kernel.org/ Signed-off-by: Roger Quadros rogerq@kernel.org Acked-by: Thinh Nguyen Thinh.Nguyen@synopsys.com --- Changes in v3: - Fix single line comment style - add DWC3_GUSB3PIPECTL_SUSPHY to documentation of susphy_state - Added Acked-by tag - Link to v2: https://lore.kernel.org/r/20241009-am62-lpm-usb-v2-1-da26c0cd2b1e@kernel.org

Changes in v2: - Fix comment style - Use both USB3 and USB2 SUSPHY bits to determine susphy_state during system suspend/resume. - Restore SUSPHY bits at system resume regardless if it was set or cleared before system suspend. - Link to v1: https://lore.kernel.org/r/20241001-am62-lpm-usb-v1-1-9916b71165f7@kernel.org --- drivers/usb/dwc3/core.c | 19 +++++++++++++++++++ drivers/usb/dwc3/core.h | 3 +++ 2 files changed, 22 insertions(+)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c index 9eb085f359ce..ca77f0b186c4 100644 --- a/drivers/usb/dwc3/core.c +++ b/drivers/usb/dwc3/core.c @@ -2336,6 +2336,11 @@ static int dwc3_suspend_common(struct dwc3 *dwc, pm_message_t msg) u32 reg; int i;

+ dwc->susphy_state = (dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0)) & + DWC3_GUSB2PHYCFG_SUSPHY) || + (dwc3_readl(dwc->regs, DWC3_GUSB3PIPECTL(0)) & + DWC3_GUSB3PIPECTL_SUSPHY); + switch (dwc->current_dr_role) { case DWC3_GCTL_PRTCAP_DEVICE: if (pm_runtime_suspended(dwc->dev)) @@ -2387,6 +2392,15 @@ static int dwc3_suspend_common(struct dwc3 *dwc, pm_message_t msg) break; }

+ if (!PMSG_IS_AUTO(msg)) { + /* + * TI AM62 platform requires SUSPHY to be + * enabled for system suspend to work. + */ + if (!dwc->susphy_state) + dwc3_enable_susphy(dwc, true); + } + return 0; }

@@ -2454,6 +2468,11 @@ static int dwc3_resume_common(struct dwc3 *dwc, pm_message_t msg) break; }

+ if (!PMSG_IS_AUTO(msg)) { + /* restore SUSPHY state to that before system suspend. */ + dwc3_enable_susphy(dwc, dwc->susphy_state); + } + return 0; }

diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h index c71240e8f7c7..31de4b57ae7c 100644 --- a/drivers/usb/dwc3/core.h +++ b/drivers/usb/dwc3/core.h @@ -1150,6 +1150,8 @@ struct dwc3_scratchpad_array { * @sys_wakeup: set if the device may do system wakeup. * @wakeup_configured: set if the device is configured for remote wakeup. * @suspended: set to track suspend event due to U3/L2. + * @susphy_state: state of DWC3_GUSB2PHYCFG_SUSPHY + DWC3_GUSB3PIPECTL_SUSPHY + * before PM suspend. * @imod_interval: set the interrupt moderation interval in 250ns * increments or 0 to disable. * @max_cfg_eps: current max number of IN eps used across all USB configs. @@ -1382,6 +1384,7 @@ struct dwc3 { unsigned sys_wakeup:1; unsigned wakeup_configured:1; unsigned suspended:1; + unsigned susphy_state:1;

u16 imod_interval;

--- base-commit: 9852d85ec9d492ebef56dc5f229416c925758edc change-id: 20240923-am62-lpm-usb-f420917bd707

Best regards,