Commit 705e3ce3 authored by Roger Quadros's avatar Roger Quadros Committed by Greg Kroah-Hartman
Browse files

usb: dwc3: core: Fix system suspend on TI AM62 platforms 

Since commit 6d735722 ("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: 6d735722 ("usb: dwc3: core: Prevent phy suspend during init")
Link: https://lore.kernel.org/all/1519dbe7-73b6-4afc-bfe3-23f4f75d772f@kernel.org/


Signed-off-by: default avatarRoger Quadros <rogerq@kernel.org>
Acked-by: default avatarThinh Nguyen <Thinh.Nguyen@synopsys.com>
Tested-by: default avatarMarkus Schneider-Pargmann <msp@baylibre.com>
Reviewed-by: default avatarDhruva Gole <d-gole@ti.com>
Link: https://lore.kernel.org/r/20241011-am62-lpm-usb-v3-1-562d445625b5@kernel.org


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 7d381137

drivers/usb/dwc3/core.c

+19 −0
Original line number Diff line number Diff line
@@ -2342,6 +2342,11 @@ 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))
@@ -2393,6 +2398,15 @@ 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;

}
@@ -2460,6 +2474,11 @@ 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;

}

drivers/usb/dwc3/core.h

+3 −0
Original line number Diff line number Diff line
@@ -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;