From 47ea030e2e68a51f91a2c2302b7ea4d3ee1a2a07 Mon Sep 17 00:00:00 2001
From: Rob Purchase <shotofadds@rockbox.org>
Date: Mon, 14 Jan 2008 22:04:48 +0000
Subject: Initial Cowon D2 commit: * bootloader test program (basic LCD &
 button drivers, reads touchscreen) * work-in-progress stubs for main build

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@16090 a1c6a512-1295-4272-9138-f99709370657
---
 firmware/target/arm/i2c-telechips.c | 187 ++++++++++++++++++++++++++++++++++++
 1 file changed, 187 insertions(+)
 create mode 100644 firmware/target/arm/i2c-telechips.c

(limited to 'firmware/target/arm/i2c-telechips.c')

diff --git a/firmware/target/arm/i2c-telechips.c b/firmware/target/arm/i2c-telechips.c
new file mode 100644
index 0000000000..e3e8fd3d33
--- /dev/null
+++ b/firmware/target/arm/i2c-telechips.c
@@ -0,0 +1,187 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2008 by Rob Purchase
+ *
+ * All files in this archive are subject to the GNU General Public License.
+ * See the file COPYING in the source tree root for full license agreement.
+ *
+ * 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 "i2c.h"
+#include "i2c-target.h"
+
+/* arbitrary delay loop */
+#define DELAY  do { int _x; for(_x=0;_x<20;_x++);} while (0)
+
+static struct mutex i2c_mtx;
+
+void i2c_init(void)
+{
+    /* nothing to do */
+}
+
+void i2c_start(void)
+{
+    SDA_OUTPUT;
+    
+    SCL_HI;
+    SDA_HI;
+    DELAY;
+    
+    SDA_LO;
+    DELAY;
+    SCL_LO;
+    DELAY;
+}
+
+void i2c_stop(void)
+{
+    SDA_OUTPUT;
+
+    SDA_LO;
+    DELAY;
+    
+    SCL_HI;
+    DELAY;
+    SDA_HI;
+    DELAY;
+}
+
+void i2c_outb(unsigned char byte)
+{
+    int bit;
+
+    SDA_OUTPUT;
+    
+    for (bit = 0; bit < 8; bit++)
+    {
+        if ((byte<<bit) & 0x80)
+          SDA_HI;
+        else
+          SDA_LO;
+          
+        DELAY;
+
+        SCL_HI;
+        DELAY;
+        SCL_LO;
+        DELAY;
+    }
+}
+
+unsigned char i2c_inb(int ack)
+{
+    int i;
+    unsigned char byte = 0;
+    
+    SDA_INPUT;
+    
+    /* clock in each bit, MSB first */
+    for ( i=0x80; i; i>>=1 )
+    {
+        SCL_HI;
+        DELAY;
+        
+        if ( SDA ) byte |= i;
+        
+        SCL_LO;
+        DELAY;
+    }
+    
+    i2c_ack(ack);
+    return byte;
+}
+
+void i2c_ack(int bit)
+{
+    SDA_OUTPUT;
+
+    if (bit)
+      SDA_HI;
+    else
+      SDA_LO;
+
+    SCL_HI;
+    DELAY;
+    SCL_LO;
+    DELAY;
+}
+
+int i2c_getack(void)
+{
+    bool ack_bit;
+    
+    SDA_INPUT;
+
+    SCL_HI;
+    DELAY;
+    
+    ack_bit = SDA;
+    DELAY;
+
+    SCL_LO;
+    DELAY;
+    
+    return ack_bit;
+}
+
+/* device = 8 bit slave address */
+int i2c_write(int device, unsigned char* buf, int count )
+{
+    int i = 0;
+    mutex_lock(&i2c_mtx);
+    
+    i2c_start();
+    i2c_outb(device & 0xfe);
+    
+    while (!i2c_getack() && i < count)
+    {
+        i2c_outb(buf[i++]);
+    }
+    
+    i2c_stop();
+    mutex_unlock(&i2c_mtx);
+    return 0;
+}
+
+
+/* device = 8 bit slave address */
+int i2c_readmem(int device, int address, unsigned char* buf, int count )
+{
+    int i = 0;
+    mutex_lock(&i2c_mtx);
+    
+    i2c_start();
+    i2c_outb(device & 0xfe);
+    if (i2c_getack()) goto exit;
+    
+    i2c_outb(address);
+    if (i2c_getack()) goto exit;
+
+    i2c_start();
+    i2c_outb(device | 1);
+    if (i2c_getack()) goto exit;
+    
+    while (i < count)
+    {
+        buf[i] = i2c_inb(i == (count-1));
+        i++;
+    }
+
+exit:
+    i2c_stop();
+    mutex_unlock(&i2c_mtx);
+    return 0;
+}
-- 
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