Commit 7c9a2598 authored by Wesley Cheng's avatar Wesley Cheng Committed by Greg Kroah-Hartman
Browse files

usb: dwc3: gadget: Preserve UDC max speed setting 



The USB gadget/UDC driver can restrict the DWC3 controller speed using
dwc3_gadget_set_speed().  Store this setting into a variable, in order for
this setting to persist across controller resets due to runtime PM.

Signed-off-by: default avatarWesley Cheng <wcheng@codeaurora.org>
Link: https://lore.kernel.org/r/1609283136-22140-3-git-send-email-wcheng@codeaurora.org


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 77adb8bd

drivers/usb/dwc3/core.h

+1 −0
Original line number Diff line number Diff line
@@ -1125,6 +1125,7 @@ struct dwc3 { 
	u32			nr_scratch;

	u32			u1u2;

	u32			maximum_speed;

	u32			gadget_max_speed;



	u32			ip;

drivers/usb/dwc3/gadget.c

+57 −51
Original line number Diff line number Diff line
@@ -2036,6 +2036,61 @@ static void dwc3_stop_active_transfers(struct dwc3 *dwc) 
	}

}



static void __dwc3_gadget_set_speed(struct dwc3 *dwc)

{

	u32			reg;



	reg = dwc3_readl(dwc->regs, DWC3_DCFG);

	reg &= ~(DWC3_DCFG_SPEED_MASK);



	/*

	 * WORKAROUND: DWC3 revision < 2.20a have an issue

	 * which would cause metastability state on Run/Stop

	 * bit if we try to force the IP to USB2-only mode.

	 *

	 * Because of that, we cannot configure the IP to any

	 * speed other than the SuperSpeed

	 *

	 * Refers to:

	 *

	 * STAR#9000525659: Clock Domain Crossing on DCTL in

	 * USB 2.0 Mode

	 */

	if (DWC3_VER_IS_PRIOR(DWC3, 220A) &&

	    !dwc->dis_metastability_quirk) {

		reg |= DWC3_DCFG_SUPERSPEED;

	} else {

		switch (dwc->gadget_max_speed) {

		case USB_SPEED_LOW:

			reg |= DWC3_DCFG_LOWSPEED;

			break;

		case USB_SPEED_FULL:

			reg |= DWC3_DCFG_FULLSPEED;

			break;

		case USB_SPEED_HIGH:

			reg |= DWC3_DCFG_HIGHSPEED;

			break;

		case USB_SPEED_SUPER:

			reg |= DWC3_DCFG_SUPERSPEED;

			break;

		case USB_SPEED_SUPER_PLUS:

			if (DWC3_IP_IS(DWC3))

				reg |= DWC3_DCFG_SUPERSPEED;

			else

				reg |= DWC3_DCFG_SUPERSPEED_PLUS;

			break;

		default:

			dev_err(dwc->dev, "invalid speed (%d)\n", dwc->gadget_max_speed);



			if (DWC3_IP_IS(DWC3))

				reg |= DWC3_DCFG_SUPERSPEED;

			else

				reg |= DWC3_DCFG_SUPERSPEED_PLUS;

		}

	}

	dwc3_writel(dwc->regs, DWC3_DCFG, reg);

}



static int dwc3_gadget_run_stop(struct dwc3 *dwc, int is_on, int suspend)

{

	u32			reg;
@@ -2058,6 +2113,7 @@ static int dwc3_gadget_run_stop(struct dwc3 *dwc, int is_on, int suspend) 
		if (dwc->has_hibernation)

			reg |= DWC3_DCTL_KEEP_CONNECT;



		__dwc3_gadget_set_speed(dwc);

		dwc->pullups_connected = true;

	} else {

		reg &= ~DWC3_DCTL_RUN_STOP;
@@ -2420,59 +2476,9 @@ static void dwc3_gadget_set_speed(struct usb_gadget *g, 
{

	struct dwc3		*dwc = gadget_to_dwc(g);

	unsigned long		flags;

	u32			reg;



	spin_lock_irqsave(&dwc->lock, flags);

	reg = dwc3_readl(dwc->regs, DWC3_DCFG);

	reg &= ~(DWC3_DCFG_SPEED_MASK);



	/*

	 * WORKAROUND: DWC3 revision < 2.20a have an issue

	 * which would cause metastability state on Run/Stop

	 * bit if we try to force the IP to USB2-only mode.

	 *

	 * Because of that, we cannot configure the IP to any

	 * speed other than the SuperSpeed

	 *

	 * Refers to:

	 *

	 * STAR#9000525659: Clock Domain Crossing on DCTL in

	 * USB 2.0 Mode

	 */

	if (DWC3_VER_IS_PRIOR(DWC3, 220A) &&

	    !dwc->dis_metastability_quirk) {

		reg |= DWC3_DCFG_SUPERSPEED;

	} else {

		switch (speed) {

		case USB_SPEED_LOW:

			reg |= DWC3_DCFG_LOWSPEED;

			break;

		case USB_SPEED_FULL:

			reg |= DWC3_DCFG_FULLSPEED;

			break;

		case USB_SPEED_HIGH:

			reg |= DWC3_DCFG_HIGHSPEED;

			break;

		case USB_SPEED_SUPER:

			reg |= DWC3_DCFG_SUPERSPEED;

			break;

		case USB_SPEED_SUPER_PLUS:

			if (DWC3_IP_IS(DWC3))

				reg |= DWC3_DCFG_SUPERSPEED;

			else

				reg |= DWC3_DCFG_SUPERSPEED_PLUS;

			break;

		default:

			dev_err(dwc->dev, "invalid speed (%d)\n", speed);



			if (DWC3_IP_IS(DWC3))

				reg |= DWC3_DCFG_SUPERSPEED;

			else

				reg |= DWC3_DCFG_SUPERSPEED_PLUS;

		}

	}

	dwc3_writel(dwc->regs, DWC3_DCFG, reg);



	dwc->gadget_max_speed = speed;

	spin_unlock_irqrestore(&dwc->lock, flags);

}