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: <stable@xxxxxxxxxxxxxxx> # v4.6+
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
---
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
