Import Mbed OS hard-float snapshot

connectivity/drivers/nfc/PN512/source/transceiver/pn512_timer.c

@@ -0,0 +1,75 @@
+/*
+ * Copyright (c) 2014-2018, ARM Limited, All Rights Reserved
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+/**
+ * \file pn512_timer.c
+ * \copyright Copyright (c) ARM Ltd 2014
+ * \author Donatien Garnier
+ */
+
+#include "stack/nfc_errors.h"
+
+#include "pn512_timer.h"
+#include "pn512_registers.h"
+
+void pn512_timer_config(pn512_t *pPN512, bool autostart, uint16_t prescaler, uint16_t countdown_value)
+{
+    pn512_timer_stop(pPN512); //just in case...
+
+    pn512_register_write(pPN512, PN512_REG_TRELOADLOW, countdown_value & 0xFF);
+    pn512_register_write(pPN512, PN512_REG_TRELOADHIGH, (countdown_value >> 8) & 0xFF);
+
+    pn512_register_write(pPN512, PN512_REG_TPRESCALERLOW, prescaler & 0xFF);
+    pn512_register_write(pPN512, PN512_REG_TMODE_TPRESCALERHIGH, (autostart ? 0x80 : 0x00) | ((prescaler >> 8) & 0x0F));
+}
+
+void pn512_timer_start(pn512_t *pPN512)
+{
+    //The control register also contains the initiator bit that we must set correctly
+    switch (pPN512->framing) {
+        case nfc_framing_initiator_a_106:
+        case nfc_framing_initiator_f_212:
+        case nfc_framing_initiator_f_424:
+            pn512_register_write(pPN512, PN512_REG_CONTROL, 0x50);
+            break;
+        case nfc_framing_target_mode_detector:
+        case nfc_framing_target_a_106:
+        case nfc_framing_target_f_212:
+        case nfc_framing_target_f_424:
+        default:
+            pn512_register_write(pPN512, PN512_REG_CONTROL, 0x40);
+            break;
+    }
+}
+
+void pn512_timer_stop(pn512_t *pPN512)
+{
+    //The control register also contains the initiator bit that we must set correctly
+    switch (pPN512->framing) {
+        case nfc_framing_initiator_a_106:
+        case nfc_framing_initiator_f_212:
+        case nfc_framing_initiator_f_424:
+            pn512_register_write(pPN512, PN512_REG_CONTROL, 0x90);
+            break;
+        case nfc_framing_target_mode_detector:
+        case nfc_framing_target_a_106:
+        case nfc_framing_target_f_212:
+        case nfc_framing_target_f_424:
+        default:
+            pn512_register_write(pPN512, PN512_REG_CONTROL, 0x80);
+            break;
+    }
+}