Add i2c definitions for it8587e

src/ec/it8587e/i2c.c

@@ -0,0 +1,79 @@
+#include <board/cpu.h>
+#include <ec/i2c.h>
+#include <ec/smbus.h>
+
+#define TIMEOUT (F_CPU/1000)
+
+#define HOSTA_BYTE_DONE (1 << 7)
+#define HOSTA_TIMEOUT (1 << 6)
+#define HOSTA_NACK (1 << 5)
+#define HOSTA_FAIL (1 << 4)
+#define HOSTA_BUS_ERR (1 << 3)
+#define HOSTA_DEV_ERR (1 << 2)
+#define HOSTA_FINISH (1 << 1)
+#define HOSTA_BUSY (1 << 0)
+#define HOSTA_ERR (HOSTA_TIMEOUT | HOSTA_NACK | HOSTA_FAIL | HOSTA_BUS_ERR | HOSTA_DEV_ERR)
+
+static void i2c_kill(void) {
+    if (HOSTAA & HOSTA_BUSY) {
+        HOCTLA = (1 << 1);
+        // TODO: is timeout needed?
+        while (HOSTAA & HOSTA_BUSY) {}
+    }
+    HOSTAA = HOSTAA;
+    HOCTLA = 0;
+    HOCTL2A = 0;
+}
+
+uint8_t i2c_transaction(uint8_t addr_rw, uint8_t *data, uint16_t length) {
+    // End any current transaction
+    i2c_kill();
+
+    // Enable host controller with i2c compatibility
+    HOCTL2A = (1 << 1) | 1;
+	// Set slave address
+	TRASLAA = addr_rw;
+
+    static uint8_t __pdata status;
+    static uint32_t __pdata timeout;
+    static uint16_t __pdata i;
+	for (i = 0; i < length; i++) {
+        if ((addr_rw & 1) && ((i + 1) == length)) {
+            // Set last byte
+            HOCTLA |= (1 << 5);
+        }
+        // Clear status
+        HOSTAA = HOSTAA;
+        if (!(addr_rw & 1)) {
+            // Set data byte
+            HOBDBA = data[i];
+        }
+        if (i == 0) {
+            // Start transaction
+            HOCTLA = (1 << 6) | (0b111 << 2);
+        }
+        for(timeout = TIMEOUT; timeout > 0; timeout++) {
+            status = HOSTAA;
+            HOSTAA = status;
+            if (status & HOSTA_ERR) {
+                timeout = 0;
+                break;
+            }
+            if (status & HOSTA_BYTE_DONE) {
+                break;
+            }
+        }
+        if (timeout == 0) {
+            i2c_kill();
+            return 1;
+        }
+        if (addr_rw & 1) {
+            // Get data byte
+            data[i] = HOBDBA;
+        }
+	}
+
+    HOCTL2A = 0;
+
+	return 0;
+}

src/ec/it8587e/include/ec/i2c.h

@@ -0,0 +1,10 @@
+#ifndef _EC_I2C_H
+#define _EC_I2C_H
+
+#include <stdint.h>
+
+uint8_t i2c_transaction(uint8_t addr_rw, uint8_t * data, uint16_t length);
+#define i2c_read(addr, data, length) i2c_transaction(((uint8_t)addr << 1) | 1, data, length)
+#define i2c_write(addr, data, length) i2c_transaction(((uint8_t)addr << 1), data, length)
+
+#endif // _EC_I2C_H