common: Add the port module.

[gps-watch.git] / src / common / port.rs

diff --git a/src/common/port.rs b/src/common/port.rs
new file mode 100644 (file)
index 0000000..0dc95a8
--- /dev/null
+++ b/src/common/port.rs
@@ -0,0 +1,80 @@
+/*
+ * Copyright (c) 2019 Tilman Sauerbeck (tilman at code-monkey de)
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+use register;
+
+type Reg32 = register::Register<u32>;
+
+const PORT_BASE: u32 = 0x40049000;
+
+pub const PORTA: u32 = PORT_BASE + 0x0000;
+pub const PORTB: u32 = PORT_BASE + 0x1000;
+pub const PORTC: u32 = PORT_BASE + 0x2000;
+pub const PORTD: u32 = PORT_BASE + 0x3000;
+pub const PORTE: u32 = PORT_BASE + 0x4000;
+
+const PORT_PCR_MUX_SHIFT: u32 = 8;
+const PORT_PCR_MUX_MASK: u32 = 3 << PORT_PCR_MUX_SHIFT;
+
+const PORT_PCR_PE: u32 = 1 << 1;
+const PORT_PCR_PS: u32 = 1 << 0;
+
+pub enum Pull {
+    None,
+    Up,
+    Down,
+}
+
+fn pcr_offset(pin: u32) -> u32 {
+    pin * 4
+}
+
+pub fn set_af(port: u32, pin: u32, af: u32) {
+    let mut pcr = Reg32::new(port + pcr_offset(pin));
+
+    pcr.modify(|v| {
+        (v & !PORT_PCR_MUX_MASK) | (af << PORT_PCR_MUX_SHIFT)
+    });
+}
+
+pub fn set_pull(port: u32, pin: u32, pull: Pull) {
+    let mut pcr = Reg32::new(port + pcr_offset(pin));
+
+    match pull {
+        Pull::None => {
+            pcr.modify(|v| {
+                v & !PORT_PCR_PE
+            });
+        },
+        Pull::Up => {
+            pcr.modify(|v| {
+                v | PORT_PCR_PE | PORT_PCR_PS
+            });
+        },
+        Pull::Down => {
+            pcr.modify(|v| {
+                (v | PORT_PCR_PE) & !PORT_PCR_PS
+            });
+        },
+    }
+}