Hammerhead: NFC: Use empty I-Block presence check.
Use empty I-blocks for presence checking as defined
in the ISO/IEC14443-4 standard.
Previous method used read binary commands, which might
inadvertently alter tag state.
Change-Id: Ib4cecb0cc80c6ef9fe7ec05169eb9e075b4f2fa0
diff --git a/nfc/libnfc-brcm-20791b05.conf b/nfc/libnfc-brcm-20791b05.conf
index ba0d846..2b72602 100644
--- a/nfc/libnfc-brcm-20791b05.conf
+++ b/nfc/libnfc-brcm-20791b05.conf
@@ -67,3 +67,13 @@
# 1 Host Wake active mode (0=ActiveLow 1=ActiveHigh)
#
#SNOOZE_MODE_CFG={08:00:00:00:01}
+
+###############################################################################
+# Choose the presence-check algorithm for type-4 tag. If not defined,
+# the default value is 1.
+# 0 NFA_RW_PRES_CHK_DEFAULT; Let stack selects an algorithm
+# 1 NFA_RW_PRES_CHK_I_BLOCK; ISO-DEP protocol's empty I-block
+# 2 NFA_RW_PRES_CHK_RESET; Deactivate to Sleep, then re-activate
+# 3 NFA_RW_PRES_CHK_RB_CH0; Type-4 tag protocol's ReadBinary command on channel 0
+# 4 NFA_RW_PRES_CHK_RB_CH3; Type-4 tag protocol's ReadBinary command on channel 3
+PRESENCE_CHECK_ALGORITHM=1
