[U-Boot] [PATCH v4 02/15] usb: dwc3: switch to peripheral mode when exiting

Jean-Jacques Hiblot jjhiblot at ti.com
Wed Sep 11 09:33:45 UTC 2019


This allow the phy to enter idle and then suspend.
the K2 platforms require the PHY to be suspended before the USB domain
clock can be turned off.

Signed-off-by: Jean-Jacques Hiblot <jjhiblot at ti.com>
---

Changes in v4: None
Changes in v3: None
Changes in v2: None

 drivers/usb/dwc3/core.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index 56e2a046bf..ae01490306 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -581,6 +581,12 @@ static int dwc3_core_init_mode(struct dwc3 *dwc)
 	return 0;
 }
 
+static void dwc3_gadget_run(struct dwc3 *dwc)
+{
+	dwc3_writel(dwc->regs, DWC3_DCTL, DWC3_DCTL_RUN_STOP);
+	mdelay(100);
+}
+
 static void dwc3_core_exit_mode(struct dwc3 *dwc)
 {
 	switch (dwc->dr_mode) {
@@ -598,6 +604,13 @@ static void dwc3_core_exit_mode(struct dwc3 *dwc)
 		/* do nothing */
 		break;
 	}
+
+	/*
+	 * switch back to peripheral mode
+	 * This enables the phy to enter idle and then, if enabled, suspend.
+	 */
+	dwc3_set_mode(dwc, DWC3_GCTL_PRTCAP_DEVICE);
+	dwc3_gadget_run(dwc);
 }
 
 #define DWC3_ALIGN_MASK		(16 - 1)
-- 
2.17.1



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