power: qpnp-charger: change USB debounce time to 20ms

To avoid spurious USBIN_VALID interrupts increase the
debounce time on the USB peripheral to 20ms.

CRs-Fixed: 433617
Change-Id: I312c8643709bc4dec3e5924b6108e934cb528680
Signed-off-by: David Keitel <dkeitel@codeaurora.org>
diff --git a/drivers/power/qpnp-charger.c b/drivers/power/qpnp-charger.c
index 510071a..7b53038 100644
--- a/drivers/power/qpnp-charger.c
+++ b/drivers/power/qpnp-charger.c
@@ -81,6 +81,7 @@
 #define CHGR_MISC_BOOT_DONE			0x42
 #define CHGR_BUCK_COMPARATOR_OVRIDE_3		0xED
 #define MISC_REVISION2				0x01
+#define USB_OVP_CTL				0x42
 #define SEC_ACCESS				0xD0
 
 /* SMBB peripheral subtype values */
@@ -99,6 +100,7 @@
 #define CHGR_BOOT_DONE			BIT(7)
 #define CHGR_CHG_EN			BIT(7)
 #define CHGR_ON_BAT_FORCE_BIT		BIT(0)
+#define USB_VALID_DEB_20MS		0x03
 
 /* Interrupt definitions */
 /* smbb_chg_interrupts */
@@ -1189,6 +1191,11 @@
 		}
 
 		rc = qpnp_chg_masked_write(chip,
+			chip->usb_chgpth_base + USB_OVP_CTL,
+			USB_VALID_DEB_20MS,
+			USB_VALID_DEB_20MS, 1);
+
+		rc = qpnp_chg_masked_write(chip,
 			chip->usb_chgpth_base + CHGR_USB_ENUM_T_STOP,
 			ENUM_T_STOP_BIT,
 			ENUM_T_STOP_BIT, 1);