Hi,
On 05/10/2024 04:04, Thinh Nguyen wrote:
Hi,
On Tue, Oct 01, 2024, Roger Quadros wrote:
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://urldefense.com/v3/__https://lore.kernel.org/all/1519dbe7-73b6-4afc-b... Signed-off-by: Roger Quadros rogerq@kernel.org
drivers/usb/dwc3/core.c | 16 ++++++++++++++++ drivers/usb/dwc3/core.h | 2 ++ 2 files changed, 18 insertions(+)
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c index 9eb085f359ce..1233922d4d54 100644 --- a/drivers/usb/dwc3/core.c +++ b/drivers/usb/dwc3/core.c @@ -2336,6 +2336,9 @@ 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);- switch (dwc->current_dr_role) { case DWC3_GCTL_PRTCAP_DEVICE: if (pm_runtime_suspended(dwc->dev))
@@ -2387,6 +2390,11 @@ static int dwc3_suspend_common(struct dwc3 *dwc, pm_message_t msg) break; }
- if (!PMSG_IS_AUTO(msg)) {
if (!dwc->susphy_state)dwc3_enable_susphy(dwc, true);- }
- return 0;
} @@ -2454,6 +2462,14 @@ static int dwc3_resume_common(struct dwc3 *dwc, pm_message_t msg) break; }
- if (!PMSG_IS_AUTO(msg)) {
/* dwc3_core_init_for_resume() disables SUSPHY so just handle* the enable case*/Can we note that this is a particular behavior needed for AM62 here? And can we use this comment style:
/*
- xxxxx
- xxxxx
*/
OK.
if (dwc->susphy_state)Shouldn't we check for if (!dwc->susphy_state) and clear the susphy bits?
In that case it would have already been cleared so no need to check and clear again.
dwc3_enable_susphy(dwc, true);The dwc3_enable_susphy() set and clear both GUSB3PIPECTL_SUSPHY and GUSB2PHYCFG_SUSPHY, perhaps we should split that function out so we can only need to set for GUSB2PHYCFG_SUSPHY since you only track for that.
As dwc3_enable_susphy() sets and clears both GUSB3PIPECTL_SUSPHY and GUSB2PHYCFG_SUSPHY together it doesn't really help to track both separately, but just complicates things.
- }
- return 0;
} diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h index c71240e8f7c7..b2ed5aba4c72 100644 --- a/drivers/usb/dwc3/core.h +++ b/drivers/usb/dwc3/core.h @@ -1150,6 +1150,7 @@ 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 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 +1383,7 @@ 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,
Roger Quadros rogerq@kernel.org
<rant/> While reviewing your change, I see that we misuse the dis_u2_susphy_quirk to make this property a conditional thing during suspend and resume for certain platform. That bugs me because we can't easily change it without the reported hardware to test. </rant>
No it is not conditional. if dis_u2_susphy_quirk or dis_u3_susphy_quirk is set then we never enable the respective U2/U3 SUSPHY bit.
Thanks for the patch!
BR, Thinh