Commit ddae7979 authored by Thinh Nguyen's avatar Thinh Nguyen Committed by Greg Kroah-Hartman
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usb: dwc3: gadget: Handle DEV_TXF_FLUSH_BYPASS capability 



DWC_usb32 IP introduces a new behavior when handling NoStream event for
IN endpoints. If the controller is capable of DEV_TXF_FLUSH_BYPASS, then
the driver does not need to force to restart stream for IN endpoints.
The controller will generate ERDY and restart the stream periodically.

Acked-by: default avatarFelipe Balbi <balbi@kernel.org>
Signed-off-by: default avatarThinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/65c3070c666cd6b8beeee62d7f8e3e704ebf2d32.1619134559.git.Thinh.Nguyen@synopsys.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 16710380

drivers/usb/dwc3/core.h

+3 −0
Original line number Diff line number Diff line
@@ -379,6 +379,9 @@ 
#define DWC3_GHWPARAMS7_RAM1_DEPTH(n)	((n) & 0xffff)

#define DWC3_GHWPARAMS7_RAM2_DEPTH(n)	(((n) >> 16) & 0xffff)



/* Global HWPARAMS9 Register */

#define DWC3_GHWPARAMS9_DEV_TXF_FLUSH_BYPASS	BIT(0)



/* Global Frame Length Adjustment Register */

#define DWC3_GFLADJ_30MHZ_SDBND_SEL		BIT(7)

#define DWC3_GFLADJ_30MHZ_MASK			0x3f

drivers/usb/dwc3/gadget.c

+9 −1
Original line number Diff line number Diff line
@@ -730,7 +730,15 @@ static int __dwc3_gadget_ep_enable(struct dwc3_ep *dep, unsigned int action) 
			 * All stream eps will reinitiate stream on NoStream

			 * rejection until we can determine that the host can

			 * prime after the first transfer.

			 *

			 * However, if the controller is capable of

			 * TXF_FLUSH_BYPASS, then IN direction endpoints will

			 * automatically restart the stream without the driver

			 * initiation.

			 */

			if (!dep->direction ||

			    !(dwc->hwparams.hwparams9 &

			      DWC3_GHWPARAMS9_DEV_TXF_FLUSH_BYPASS))

				dep->flags |= DWC3_EP_FORCE_RESTART_STREAM;

		}

	}