Re: [PATCH v2 10/12] usb: dwc2: Add clock gating entering flow by system suspend

Sergei Shtylyov <sergei.shtylyov@xxxxxxxxx> · Tue, 13 Apr 2021 12:29:41 +0300

On 13.04.2021 10:37, Artur Petrosyan wrote:

If not hibernation nor partial power down are supported,

   s/not/neither/?

clock gating is used to save power.

Adds a new flow of entering clock gating when PC is
suspended.

Signed-off-by: Artur Petrosyan <Arthur.Petrosyan@xxxxxxxxxxxx>
---
  Changes in v2:
  - None

  drivers/usb/dwc2/hcd.c | 9 +++++++++
  1 file changed, 9 insertions(+)

diff --git a/drivers/usb/dwc2/hcd.c b/drivers/usb/dwc2/hcd.c
index 31d6a1b87228..09dcd37b9ef8 100644
--- a/drivers/usb/dwc2/hcd.c
+++ b/drivers/usb/dwc2/hcd.c
@@ -4372,6 +4372,15 @@ static int _dwc2_hcd_suspend(struct usb_hcd *hcd)
  		break;
  	case DWC2_POWER_DOWN_PARAM_HIBERNATION:
  	case DWC2_POWER_DOWN_PARAM_NONE:
+		/*
+		 * If not hibernation nor partial power down are supported,

   s/not/neither/?

+		 * clock gating is used to save power.
+		 */
+		dwc2_host_enter_clock_gating(hsotg);
+
+		/* After entering suspend, hardware is not accessible */
+		clear_bit(HCD_FLAG_HW_ACCESSIBLE, &hcd->flags);
+		break;
  	default:
  		goto skip_power_saving;
  	}
MBR, Sergei






