Since the controller on R-Car Gen3 doesn't have any status registers
to detect initialization (LPSTS.SUSPM = 1) and the initialization needs
up to 45 usec, this patch adds wait after the initialization. Otherwise,
writing other registers (e.g. INTENB0) will fail.

Fixes: de18757e272d ("usb: renesas_usbhs: add R-Car Gen3 power control")
Cc: <[email protected]> # v4.6+
Signed-off-by: Yoshihiro Shimoda <[email protected]>
---
 This patch is based on the latest Felipe's usb.git / testing/fixes branch
 (commit id = a1aa8cf6471b17c0fa7132ea5eeef0ae07ca07cd).

 drivers/usb/renesas_usbhs/rcar3.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/renesas_usbhs/rcar3.c 
b/drivers/usb/renesas_usbhs/rcar3.c
index 1d70add..d544b33 100644
--- a/drivers/usb/renesas_usbhs/rcar3.c
+++ b/drivers/usb/renesas_usbhs/rcar3.c
@@ -9,6 +9,7 @@
  *
  */
 
+#include <linux/delay.h>
 #include <linux/io.h>
 #include "common.h"
 #include "rcar3.h"
@@ -35,10 +36,13 @@ static int usbhs_rcar3_power_ctrl(struct platform_device 
*pdev,
 
        usbhs_write32(priv, UGCTRL2, UGCTRL2_RESERVED_3 | UGCTRL2_USB0SEL_OTG);
 
-       if (enable)
+       if (enable) {
                usbhs_bset(priv, LPSTS, LPSTS_SUSPM, LPSTS_SUSPM);
-       else
+               /* The controller on R-Car Gen3 needs to wait up to 45 usec */
+               udelay(45);
+       } else {
                usbhs_bset(priv, LPSTS, LPSTS_SUSPM, 0);
+       }
 
        return 0;
 }
-- 
1.9.1

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