1 files changed, 136 insertions, 0 deletions
diff --git a/firmware/target/arm/s5l8700/i2c-s5l8700.c b/firmware/target/arm/s5l8700/i2c-s5l8700.c
new file mode 100644
index 0000000000..564bfdd4bd
--- /dev/null
+++ b/firmware/target/arm/s5l8700/i2c-s5l8700.c
@@ -0,0 +1,136 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2009 by Bertrik Sikken
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+ 
+#include "config.h"
+#include "system.h"
+#include "kernel.h"
+#include "i2c-s5l8700.h"
+
+/*  Driver for the s5l8700 built-in I2C controller in master mode
+    
+    Both the i2c_read and i2c_write function take the following arguments:
+    * slave, the address of the i2c slave device to read from / write to
+    * address, optional sub-address in the i2c slave (unused if -1)
+    * len, number of bytes to be transfered
+    * data, pointer to data to be transfered
+    A return value < 0 indicates an error.
+    
+    Known issues:
+    * uses polled mode (not interrupt driven), just like the OF
+    * ACK from slave is not checked, so functions never return an error
+*/
+
+static struct mutex i2c_mtx;
+
+void i2c_init(void)
+{
+    mutex_init(&i2c_mtx);
+
+    /* enable I2C pins */
+    PCON10 = (2 << 2) |
+             (2 << 0);
+
+    /* enable I2C clock */
+    PWRCON &= ~(1 << 5);
+
+    /* initial config */
+    IICADD = 0;
+    IICCON = (1 << 7) | /* ACK_GEN */
+             (1 << 6) | /* CLKSEL = PCLK/512 */
+             (1 << 5) | /* INT_EN */
+             (1 << 4) | /* IRQ clear */
+             (3 << 0);  /* CK_REG */
+
+    /* serial output on */
+    IICSTAT = (1 << 4);
+}
+
+int i2c_write(unsigned char slave, int address, int len, const unsigned char *data)
+{
+    mutex_lock(&i2c_mtx);
+
+    /* START */
+    IICDS = slave & ~1;
+    IICSTAT = 0xF0;
+    IICCON = 0xF3;
+    while ((IICCON & (1 << 4)) == 0);
+    
+    if (address >= 0) {
+        /* write address */
+        IICDS = address;
+        IICCON = 0xF3;
+        while ((IICCON & (1 << 4)) == 0);
+    }
+    
+    /* write data */
+    while (len--) {
+        IICDS = *data++;
+        IICCON = 0xF3;
+        while ((IICCON & (1 << 4)) == 0);
+    }
+
+    /* STOP */
+    IICSTAT = 0xD0;
+    IICCON = 0xF3;
+    while ((IICSTAT & (1 << 5)) != 0);
+    
+    mutex_unlock(&i2c_mtx);
+    return 0;
+}
+
+int i2c_read(unsigned char slave, int address, int len, unsigned char *data)
+{
+    mutex_lock(&i2c_mtx);
+
+    if (address >= 0) {
+        /* START */
+        IICDS = slave & ~1;
+        IICSTAT = 0xF0;
+        IICCON = 0xF3;
+        while ((IICCON & (1 << 4)) == 0);
+
+        /* write address */
+        IICDS = address;
+        IICCON = 0xF3;
+        while ((IICCON & (1 << 4)) == 0);
+    }
+    
+    /* (repeated) START */
+    IICDS = slave | 1;
+    IICSTAT = 0xB0;
+    IICCON = 0xF3;
+    while ((IICCON & (1 << 4)) == 0);
+    
+    while (len--) {
+        IICCON = (len == 0) ? 0x73 : 0xF3; /* NACK or ACK */
+        while ((IICCON & (1 << 4)) == 0);
+        *data++ = IICDS;
+    }
+
+    /* STOP */
+    IICSTAT = 0x90;
+    IICCON = 0xF3;
+    while ((IICSTAT & (1 << 5)) != 0);
+    
+    mutex_unlock(&i2c_mtx);
+    return 0;
+}
+