Move the Synaptics touchpad driver for the m:robe 100 to a common place. It will (soon) be used for the Philips HDD1630.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@19465 a1c6a512-1295-4272-9138-f99709370657

4 files changed, 530 insertions, 477 deletions

diff --git a/firmware/SOURCES b/firmware/SOURCES
index 5d1dd0d800..441f75d31d 100644
--- a/firmware/SOURCES
+++ b/firmware/SOURCES
@@ -820,6 +820,9 @@ target/arm/tms320dm320/creative-zvm/usb-creativezvm.c
 
 #ifdef MROBE_100
 #ifndef SIMULATOR
+#ifndef BOOTLOADER
+drivers/synaptics-mep.c
+#endif /* BOOTLOADER */
 drivers/sw_i2c.c
 target/arm/ata-as-arm.S
 target/arm/ata-pp5020.c
diff --git a/firmware/drivers/synaptics-mep.c b/firmware/drivers/synaptics-mep.c
new file mode 100644
index 0000000000..44b186034f
--- /dev/null
+++ b/firmware/drivers/synaptics-mep.c
@@ -0,0 +1,482 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2008 by Mark Arigo
+ *
+ * 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 <stdlib.h>
+#include "config.h"
+#include "cpu.h"
+#include "system.h"
+#include "kernel.h"
+#include "system.h"
+
+#define LOGF_ENABLE
+#include "logf.h"
+
+/* Driver for the Synaptics Touchpad based on the "Synaptics Modular Embedded
+   Protocol: 3-Wire Interface Specification" documentation */
+
+#define ACK     (GPIOD_INPUT_VAL & 0x1)
+#define ACK_HI  GPIOD_OUTPUT_VAL |=  0x1
+#define ACK_LO  GPIOD_OUTPUT_VAL &= ~0x1
+
+#define CLK     ((GPIOD_INPUT_VAL & 0x2) >> 1)
+#define CLK_HI  GPIOD_OUTPUT_VAL |=  0x2
+#define CLK_LO  GPIOD_OUTPUT_VAL &= ~0x2
+
+#define DATA    ((GPIOD_INPUT_VAL & 0x4) >> 2)
+#define DATA_HI GPIOD_OUTPUT_EN |= 0x4; GPIOD_OUTPUT_VAL |=  0x4
+#define DATA_LO GPIOD_OUTPUT_EN |= 0x4; GPIOD_OUTPUT_VAL &= ~0x4
+#define DATA_CL GPIOD_OUTPUT_EN &= ~0x4
+
+#define LO 0
+#define HI 1
+
+#define READ_RETRY      8
+#define READ_ERROR     -1
+
+#define MEP_HELLO_HEADER 0x19
+#define MEP_HELLO_ID     0x1
+
+#define MEP_READ  0x1
+#define MEP_WRITE 0x3
+
+static int syn_wait_clk_change(unsigned int val)
+{
+    int i;
+
+    for (i = 0; i < 10000; i++)
+    {
+        if (CLK == val)
+            return 1;
+    }
+
+    return 0;
+}
+
+static inline int syn_get_data(void)
+{
+    DATA_CL;
+    return DATA;
+}
+
+static void syn_wait_guest_flush(void)
+{
+    /* Flush receiving (flushee) state:
+       handshake until DATA goes high during P3 stage */
+    if (CLK == LO)
+    {
+        ACK_HI;                  /* P1 -> P2 */
+        syn_wait_clk_change(HI); /* P2 -> P3 */
+    }
+
+    while (syn_get_data() == LO)
+    {
+        ACK_HI;                  /* P3 -> P0 */
+        syn_wait_clk_change(LO); /* P0 -> P1 */
+        ACK_LO;                  /* P1 -> P2 */
+        syn_wait_clk_change(HI); /* P2 -> P3 */
+    }
+
+    /* Continue handshaking until back to P0 */
+    ACK_HI;                      /* P3 -> P0 */
+}
+
+static void syn_flush(void)
+{
+    int i;
+
+    logf("syn_flush...");
+
+    /* Flusher holds DATA low for at least 36 handshake cycles */
+    DATA_LO;
+
+    for (i = 0; i < 36; i++)
+    {
+        syn_wait_clk_change(LO); /* P0 -> P1 */
+        ACK_LO;                  /* P1 -> P2 */
+        syn_wait_clk_change(HI); /* P2 -> P3 */
+        ACK_HI;                  /* P3 -> P0 */
+    }
+
+    /* Raise DATA in P1 stage */
+    syn_wait_clk_change(LO); /* P0 -> P1 */
+    DATA_HI;
+
+    /* After a flush, the flushing device enters a flush-receiving (flushee)
+       state */
+    syn_wait_guest_flush();
+}
+
+static int syn_send_data(int *data, int len)
+{
+    int i, bit;
+    int parity = 0;
+
+    logf("syn_send_data...");
+
+    /* 1. Lower DATA line to issue a request-to-send to guest */
+    DATA_LO;
+
+    /* 2. Wait for guest to lower CLK */
+    syn_wait_clk_change(LO);
+
+    /* 3. Lower ACK (with DATA still low) */
+    ACK_LO;
+
+    /* 4. Wait for guest to raise CLK */
+    syn_wait_clk_change(HI);
+
+    /* 5. Send data */
+    for (i = 0; i < len; i++)
+    {
+       logf("  sending byte: %d", data[i]);
+
+        bit = 0;
+        while (bit < 8)
+        {
+            /* 5a. Drive data low if bit is 0, or high if bit is 1 */
+            if (data[i] & (1 << bit))
+            {
+                DATA_HI;
+                parity++;
+            }
+            else
+            {
+                DATA_LO;
+            }
+            bit++;
+
+            /* 5b. Invert ACK to indicate that the data bit is ready */
+            ACK_HI;
+
+            /* 5c. Wait for guest to invert CLK */
+            syn_wait_clk_change(LO);
+
+            /* Repeat for next bit */
+            if (data[i] & (1 << bit))
+            {
+                DATA_HI;
+                parity++;
+            }
+            else
+            {
+                DATA_LO;
+            }
+            bit++;
+
+            ACK_LO;
+
+            syn_wait_clk_change(HI);
+        }
+    }
+
+    /* 7. Transmission termination sequence: */
+    /* 7a. Host may put parity bit on DATA. Hosts that do not generate
+           parity should set DATA high. Parity is 1 if there's an odd
+           number of '1' bits, or 0 if there's an even number of '1' bits. */
+    parity = parity % 2;
+    if (parity)
+    {
+        DATA_HI;
+    }
+    else
+    {
+        DATA_LO;
+    }
+    logf("  send parity = %d", parity);
+
+    /* 7b. Raise ACK to indicate that the optional parity bit is ready */
+    ACK_HI;
+
+    /* 7c. Guest lowers CLK */
+    syn_wait_clk_change(LO);
+
+    /* 7d. Pull DATA high (if parity bit was 0) */
+    DATA_HI;
+
+    /* 7e. Lower ACK to indicate that the stop bit is ready */
+    ACK_LO;
+
+    /* 7f. Guest raises CLK */
+    syn_wait_clk_change(HI);
+
+    /* 7g. If DATA is low, guest is flushing this transfer. Host should
+           enter the flushee state. */
+    if (syn_get_data() == LO)
+    {
+        logf("  module flushing");
+
+        syn_wait_guest_flush();
+        return -1;
+    }
+
+    /* 7h. Host raises ACK and the link enters the idle state */
+    ACK_HI;
+
+    return len;
+}
+
+static int syn_read_data(int *data, int data_len)
+{
+    int i, len, bit, parity, tmp;
+    int *data_ptr;
+
+    logf("syn_read_data...");
+
+    /* 1. Guest drives CLK low */
+    if (CLK != LO)
+        return 0;
+
+    /* 1a. If the host is willing to receive a packet it lowers ACK */
+    ACK_LO;
+
+    /* 2. Guest may issue a request-to-send by lowering DATA. If the
+          guest decides not to transmit a packet, it may abort the
+          transmission by not lowering DATA. */
+
+    /* 3. The guest raises CLK */
+    syn_wait_clk_change(HI);
+
+    /* 4. If the guest is still driving DATA low, the transfer is commited
+          to occur. Otherwise, the transfer is aborted. In either case, 
+          the host raises ACK. */
+    if (syn_get_data() == HI)
+    {
+        logf("  read abort");
+
+        ACK_HI;
+        return READ_ERROR;
+    }
+    else
+    {
+        ACK_HI;
+    }
+
+    /* 5. Read the incoming data packet */
+    i = 0;
+    len = 0;
+    parity = 0;
+    while (i <= len)
+    {
+        bit = 0;
+
+        if (i < data_len)
+            data_ptr = &data[i];
+        else
+            data_ptr = &tmp;
+
+        *data_ptr = 0;
+        while (bit < 8)
+        {
+            /* 5b. Guset inverts CLK to indicate that data is ready */
+            syn_wait_clk_change(LO);
+
+            /* 5d. Read the data bit from DATA */
+            if (syn_get_data() == HI)
+            {
+                *data_ptr |= (1 << bit);
+                parity++;
+            }
+            bit++;
+
+            /* 5e. Invert ACK to indicate that data has been read */
+            ACK_LO;
+
+            /* Repeat for next bit */
+            syn_wait_clk_change(HI);
+
+            if (syn_get_data() == HI)
+            {
+                *data_ptr |= (1 << bit);
+                parity++;
+            }
+            bit++;
+
+            ACK_HI;
+        }
+
+        /* First byte is the packet header */
+        if (i == 0)
+        {
+            /* Format control (bit 3) should be 1 */
+            if (*data_ptr & 0x8)
+            {
+                /* Packet length is bits 0:2 */
+                len = *data_ptr & 0x7;
+                logf("  packet length = %d", len);
+            }
+            else
+            {
+                logf("  invalid format ctrl bit");
+                return READ_ERROR;
+            }
+        }
+
+        i++;
+    }
+
+    /* 7. Transmission termination cycle */
+    /* 7a. The guest generates a parity bit on DATA */
+    /* 7b. The host waits for guest to lower CLK */
+    syn_wait_clk_change(LO);
+
+    /* 7c. The host verifies the parity bit is correct */
+    parity = parity % 2;
+    logf("  parity check: %d / %d", syn_get_data(), parity);
+
+    /* TODO: parity error handling */
+
+    /* 7d. The host lowers ACK */
+    ACK_LO;
+
+    /* 7e. The host waits for the guest to raise CLK indicating 
+           that the stop bit is ready */
+    syn_wait_clk_change(HI);
+
+    /* 7f. The host reads DATA and verifies that it is 1 */
+    if (syn_get_data() == LO)
+    {
+        logf("  framing error");
+
+        ACK_HI;
+        return READ_ERROR;
+    }
+
+    ACK_HI;
+
+    return len;
+}
+
+int syn_read_device(int *data, int len)
+{
+    int i;
+    int ret = READ_ERROR;
+
+    for (i = 0; i < READ_RETRY; i++)
+    {
+        if (syn_wait_clk_change(LO))
+        {
+            /* module is sending data */
+            ret = syn_read_data(data, len);
+            if (ret != READ_ERROR)
+                return ret;
+
+            syn_flush();
+        }
+        else
+        {
+            /* module is idle */
+            return 0;
+        }
+    }
+
+    return ret;
+}
+
+static int syn_reset(void)
+{
+    int val, id;
+    int data[2];
+
+    logf("syn_reset...");
+
+    /* reset module 0 */
+    val = (0 << 4) | (1 << 3) | 0;
+    syn_send_data(&val, 1);
+
+    val = syn_read_device(data, 2);
+    if (val == 1)
+    {
+        val = data[0] & 0xff;      /* packet header */
+        id = (data[1] >> 4) & 0xf; /* packet id */
+        if ((val == MEP_HELLO_HEADER) && (id == MEP_HELLO_ID))
+        {
+            logf("  module 0 reset");
+            return 1;
+        }
+    }
+
+    logf("  reset failed");
+    return 0;
+}
+
+int syn_init(void)
+{
+    syn_flush();
+    return syn_reset();
+}
+
+#ifdef ROCKBOX_HAS_LOGF
+void syn_info(void)
+{
+    int i, val;
+    int data[8];
+
+    logf("syn_info...");
+
+    /* module base info */
+    logf("module base info:");
+    data[0] = MEP_READ;
+    data[1] = 0x80;
+    syn_send_data(data, 2);
+    val = syn_read_device(data, 8);
+    if (val > 0)
+    {
+        for (i = 0; i < 8; i++)
+            logf("  data[%d] = 0x%02x", i, data[i]);
+    }
+    
+    /* module product info */
+    logf("module product info:");
+    data[0] = MEP_READ;
+    data[1] = 0x81;
+    syn_send_data(data, 2);
+    val = syn_read_device(data, 8);
+    if (val > 0)
+    {
+        for (i = 0; i < 8; i++)
+            logf("  data[%d] = 0x%02x", i, data[i]);
+    }
+
+    /* module serialization */
+    logf("module serialization:");
+    data[0] = MEP_READ;
+    data[1] = 0x82;
+    syn_send_data(data, 2);
+    val = syn_read_device(data, 8);
+    if (val > 0)
+    {
+        for (i = 0; i < 8; i++)
+            logf("  data[%d] = 0x%02x", i, data[i]);
+    }
+
+    /* 1-D sensor info */
+    logf("1-d sensor info:");
+    data[0] = MEP_READ;
+    data[1] = 0x80 + 0x20;
+    syn_send_data(data, 2);
+    val = syn_read_device(data, 8);
+    if (val > 0)
+    {
+        for (i = 0; i < 8; i++)
+            logf("  data[%d] = 0x%02x", i, data[i]);
+    }
+}
+#endif
diff --git a/firmware/export/synaptics-mep.h b/firmware/export/synaptics-mep.h
new file mode 100644
index 0000000000..8f717da884
--- /dev/null
+++ b/firmware/export/synaptics-mep.h
@@ -0,0 +1,27 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2008 by Mark Arigo
+ *
+ * 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.
+ *
+ ****************************************************************************/
+
+int syn_init(void);
+int syn_read_device(int *data, int len);
+
+#ifdef ROCKBOX_HAS_LOGF
+void syn_info(void);
+#endif
diff --git a/firmware/target/arm/olympus/mrobe-100/button-mr100.c b/firmware/target/arm/olympus/mrobe-100/button-mr100.c
index e8fc8b97ea..9cfd8affa9 100644
--- a/firmware/target/arm/olympus/mrobe-100/button-mr100.c
+++ b/firmware/target/arm/olympus/mrobe-100/button-mr100.c
@@ -19,480 +19,24 @@
  *
  ****************************************************************************/
 
-#include <stdlib.h>
-#include "config.h"
-#include "cpu.h"
 #include "system.h"
 #include "button.h"
-#include "kernel.h"
 #include "backlight.h"
 #include "backlight-target.h"
-#include "system.h"
+#include "synaptics-mep.h"
 
 #define LOGF_ENABLE
 #include "logf.h"
 
+#define MEP_BUTTON_HEADER   0x1a
+#define MEP_BUTTON_ID       0x9
+#define MEP_ABSOLUTE_HEADER 0x0b
+
 static int int_btn = BUTTON_NONE;
 
 #ifndef BOOTLOADER
-/* Driver for the Synaptics Touchpad based on the "Synaptics Modular Embedded
-   Protocol: 3-Wire Interface Specification" documentation */
-
-#define ACK     (GPIOD_INPUT_VAL & 0x1)
-#define ACK_HI  GPIOD_OUTPUT_VAL |=  0x1
-#define ACK_LO  GPIOD_OUTPUT_VAL &= ~0x1
-
-#define CLK     ((GPIOD_INPUT_VAL & 0x2) >> 1)
-#define CLK_HI  GPIOD_OUTPUT_VAL |=  0x2
-#define CLK_LO  GPIOD_OUTPUT_VAL &= ~0x2
-
-#define DATA    ((GPIOD_INPUT_VAL & 0x4) >> 2)
-#define DATA_HI GPIOD_OUTPUT_EN |= 0x4; GPIOD_OUTPUT_VAL |=  0x4
-#define DATA_LO GPIOD_OUTPUT_EN |= 0x4; GPIOD_OUTPUT_VAL &= ~0x4
-
-#define LO 0
-#define HI 1
-
-#define STATUS_READY    1
-#define READ_RETRY      8
-#define READ_ERROR     -1
-
-#define HELLO_HEADER    0x19
-#define HELLO_ID        0x1
-#define BUTTONS_HEADER  0x1a
-#define BUTTONS_ID      0x9
-#define ABSOLUTE_HEADER 0x0b
-
-#define MEP_READ 0x1
-#define MEP_WRITE 0x3
-
 static int syn_status = 0;
 
-static int syn_wait_clk_change(unsigned int val)
-{
-    int i;
-
-    for (i = 0; i < 10000; i++)
-    {
-        if (CLK == val)
-            return 1;
-    }
-
-    return 0;
-}
-
-static inline int syn_get_data(void)
-{
-    GPIOD_OUTPUT_EN &= ~0x4;
-    return DATA;
-}
-
-static void syn_wait_guest_flush(void)
-{
-    /* Flush receiving (flushee) state:
-       handshake until DATA goes high during P3 stage */
-    if (CLK == LO)
-    {
-        ACK_HI;                  /* P1 -> P2 */
-        syn_wait_clk_change(HI); /* P2 -> P3 */
-    }
-
-    while (syn_get_data() == LO)
-    {
-        ACK_HI;                  /* P3 -> P0 */
-        syn_wait_clk_change(LO); /* P0 -> P1 */
-        ACK_LO;                  /* P1 -> P2 */
-        syn_wait_clk_change(HI); /* P2 -> P3 */
-    }
-
-    /* Continue handshaking until back to P0 */
-    ACK_HI;                      /* P3 -> P0 */
-}
-
-static void syn_flush(void)
-{
-    int i;
-#if defined(LOGF_ENABLE)
-    logf("syn_flush...");
-#endif
-    /* Flusher holds DATA low for at least 36 handshake cycles */
-    DATA_LO;
-
-    for (i = 0; i < 36; i++)
-    {
-        syn_wait_clk_change(LO); /* P0 -> P1 */
-        ACK_LO;                  /* P1 -> P2 */
-        syn_wait_clk_change(HI); /* P2 -> P3 */
-        ACK_HI;                  /* P3 -> P0 */
-    }
-
-    /* Raise DATA in P1 stage */
-    syn_wait_clk_change(LO); /* P0 -> P1 */
-    DATA_HI;
-
-    /* After a flush, the flushing device enters a flush-receiving (flushee)
-       state */
-    syn_wait_guest_flush();
-}
-
-static int syn_send_data(int *data, int len)
-{
-    int i, bit;
-    int parity = 0;
-#if defined(LOGF_ENABLE)
-    logf("syn_send_data...");
-#endif
-    /* 1. Lower DATA line to issue a request-to-send to guest */
-    DATA_LO;
-
-    /* 2. Wait for guest to lower CLK */
-    syn_wait_clk_change(LO);
-
-    /* 3. Lower ACK (with DATA still low) */
-    ACK_LO;
-
-    /* 4. Wait for guest to raise CLK */
-    syn_wait_clk_change(HI);
-
-    /* 5. Send data */
-    for (i = 0; i < len; i++)
-    {
-#if defined(LOGF_ENABLE)
-       logf("  sending byte: %d", data[i]);
-#endif
-        bit = 0;
-        while (bit < 8)
-        {
-            /* 5a. Drive data low if bit is 0, or high if bit is 1 */
-            if (data[i] & (1 << bit))
-            {
-                DATA_HI;
-                parity++;
-            }
-            else
-            {
-                DATA_LO;
-            }
-            bit++;
-
-            /* 5b. Invert ACK to indicate that the data bit is ready */
-            ACK_HI;
-
-            /* 5c. Wait for guest to invert CLK */
-            syn_wait_clk_change(LO);
-
-            /* Repeat for next bit */
-            if (data[i] & (1 << bit))
-            {
-                DATA_HI;
-                parity++;
-            }
-            else
-            {
-                DATA_LO;
-            }
-            bit++;
-
-            ACK_LO;
-
-            syn_wait_clk_change(HI);
-        }
-    }
-
-    /* 7. Transmission termination sequence: */
-    /* 7a. Host may put parity bit on DATA. Hosts that do not generate
-           parity should set DATA high. Parity is 1 if there's an odd
-           number of '1' bits, or 0 if there's an even number of '1' bits. */
-    parity = parity % 2;
-#if defined(LOGF_ENABLE)    
-    logf("  send parity = %d", parity);
-#endif   
-    if (parity)
-    {
-        DATA_HI;
-    }
-    else
-    {
-        DATA_LO;
-    }
-
-    /* 7b. Raise ACK to indicate that the optional parity bit is ready */
-    ACK_HI;
-
-    /* 7c. Guest lowers CLK */
-    syn_wait_clk_change(LO);
-
-    /* 7d. Pull DATA high (if parity bit was 0) */
-    DATA_HI;
-
-    /* 7e. Lower ACK to indicate that the stop bit is ready */
-    ACK_LO;
-
-    /* 7f. Guest raises CLK */
-    syn_wait_clk_change(HI);
-
-    /* 7g. If DATA is low, guest is flushing this transfer. Host should
-           enter the flushee state. */
-    if (syn_get_data() == LO)
-    {
-#if defined(LOGF_ENABLE)
-        logf("  module flushing");
-#endif     
-        syn_wait_guest_flush();
-        return -1;
-    }
-
-    /* 7h. Host raises ACK and the link enters the idle state */
-    ACK_HI;
-
-    return len;
-}
-
-static int syn_read_data(int *data, int data_len)
-{
-    int i, len, bit, parity, tmp;
-    int *data_ptr;
-#if defined(LOGF_ENABLE)
-    logf("syn_read_data...");
-#endif
-    /* 1. Guest drives CLK low */
-    if (CLK != LO)
-        return 0;
-
-    /* 1a. If the host is willing to receive a packet it lowers ACK */
-    ACK_LO;
-
-    /* 2. Guest may issue a request-to-send by lowering DATA. If the
-          guest decides not to transmit a packet, it may abort the
-          transmission by not lowering DATA. */
-
-    /* 3. The guest raises CLK */
-    syn_wait_clk_change(HI);
-
-    /* 4. If the guest is still driving DATA low, the transfer is commited
-          to occur. Otherwise, the transfer is aborted. In either case, 
-          the host raises ACK. */
-    if (syn_get_data() == HI)
-    {
-        logf("  read abort");
-
-        ACK_HI;
-        return READ_ERROR;
-    }
-    else
-    {
-        ACK_HI;
-    }
-
-    /* 5. Read the incoming data packet */
-    i = 0;
-    len = 0;
-    parity = 0;
-    while (i <= len)
-    {
-        bit = 0;
-
-        if (i < data_len)
-            data_ptr = &data[i];
-        else
-            data_ptr = &tmp;
-
-        *data_ptr = 0;
-        while (bit < 8)
-        {
-            /* 5b. Guset inverts CLK to indicate that data is ready */
-            syn_wait_clk_change(LO);
-
-            /* 5d. Read the data bit from DATA */
-            if (syn_get_data() == HI)
-            {
-                *data_ptr |= (1 << bit);
-                parity++;
-            }
-            bit++;
-
-            /* 5e. Invert ACK to indicate that data has been read */
-            ACK_LO;
-
-            /* Repeat for next bit */
-            syn_wait_clk_change(HI);
-
-            if (syn_get_data() == HI)
-            {
-                *data_ptr |= (1 << bit);
-                parity++;
-            }
-            bit++;
-
-            ACK_HI;
-        }
-
-        /* First byte is the packet header */
-        if (i == 0)
-        {
-            /* Format control (bit 3) should be 1 */
-            if (*data_ptr & 0x8)
-            {
-                /* Packet length is bits 0:2 */
-                len = *data_ptr & 0x7;
-#if defined(LOGF_ENABLE)
-                logf("  packet length = %d", len);
-#endif
-            }
-            else
-            {
-                logf("  invalid format ctrl bit");
-                return READ_ERROR;
-            }
-        }
-
-        i++;
-    }
-
-    /* 7. Transmission termination cycle */
-    /* 7a. The guest generates a parity bit on DATA */
-    /* 7b. The host waits for guest to lower CLK */
-    syn_wait_clk_change(LO);
-
-    /* 7c. The host verifies the parity bit is correct */
-    parity = parity % 2;
-#if defined(LOGF_ENABLE)
-    logf("  parity check: %d / %d", syn_get_data(), parity);
-#endif
-    /* TODO: parity error handling */
-
-    /* 7d. The host lowers ACK */
-    ACK_LO;
-
-    /* 7e. The host waits for the guest to raise CLK indicating 
-           that the stop bit is ready */
-    syn_wait_clk_change(HI);
-
-    /* 7f. The host reads DATA and verifies that it is 1 */
-    if (syn_get_data() == LO)
-    {
-        logf("  framing error");
-
-        ACK_HI;
-        return READ_ERROR;
-    }
-
-    ACK_HI;
-
-    return len;
-}
-
-static int syn_read_device(int *data, int len)
-{
-    int i;
-    int ret = READ_ERROR;
-
-    for (i = 0; i < READ_RETRY; i++)
-    {
-        if (syn_wait_clk_change(LO))
-        {
-            /* module is sending data */
-            ret = syn_read_data(data, len);
-            if (ret != READ_ERROR)
-                return ret;
-
-            syn_flush();
-        }
-        else
-        {
-            /* module is idle */
-            return 0;
-        }
-    }
-
-    return ret;
-}
-
-static int syn_reset(void)
-{
-    int val, id;
-    int data[2];
-#if defined(LOGF_ENABLE)
-    logf("syn_reset...");
-#endif
-    /* reset module 0 */
-    val = (0 << 4) | (1 << 3) | 0;
-    syn_send_data(&val, 1);
-
-    val = syn_read_device(data, 2);
-    if (val == 1)
-    {
-        val = data[0] & 0xff;      /* packet header */
-        id = (data[1] >> 4) & 0xf; /* packet id */
-        if ((val == HELLO_HEADER) && (id == HELLO_ID))
-        {
-            logf("  module 0 reset");
-            return 1;
-        }
-    }
-
-    logf("  reset failed");
-    return 0;
-}
-
-#if defined(ROCKBOX_HAS_LOGF) && defined(LOGF_ENABLE)
-static void syn_info(void)
-{
-    int i, val;
-    int data[8];
-
-    logf("syn_info...");
-
-    /* module base info */
-    logf("module base info:");
-    data[0] = MEP_READ;
-    data[1] = 0x80;
-    syn_send_data(data, 2);
-    val = syn_read_device(data, 8);
-    if (val > 0)
-    {
-        for (i = 0; i < 8; i++)
-            logf("  data[%d] = 0x%02x", i, data[i]);
-    }
-    
-    /* module product info */
-    logf("module product info:");
-    data[0] = MEP_READ;
-    data[1] = 0x81;
-    syn_send_data(data, 2);
-    val = syn_read_device(data, 8);
-    if (val > 0)
-    {
-        for (i = 0; i < 8; i++)
-            logf("  data[%d] = 0x%02x", i, data[i]);
-    }
-
-    /* module serialization */
-    logf("module serialization:");
-    data[0] = MEP_READ;
-    data[1] = 0x82;
-    syn_send_data(data, 2);
-    val = syn_read_device(data, 8);
-    if (val > 0)
-    {
-        for (i = 0; i < 8; i++)
-            logf("  data[%d] = 0x%02x", i, data[i]);
-    }
-
-    /* 1-D sensor info */
-    logf("1-d sensor info:");
-    data[0] = MEP_READ;
-    data[1] = 0x80 + 0x20;
-    syn_send_data(data, 2);
-    val = syn_read_device(data, 8);
-    if (val > 0)
-    {
-        for (i = 0; i < 8; i++)
-            logf("  data[%d] = 0x%02x", i, data[i]);
-    }
-}
-#endif
-
 void button_init_device(void)
 {
     /* enable touchpad leds */
@@ -514,15 +58,13 @@ void button_init_device(void)
     GPIOD_OUTPUT_EN  |=  0x4; /* DATA */
     GPIOD_OUTPUT_VAL |=  0x4; /* high */
 
-    syn_flush();
-
-    if (syn_reset())
+    if (syn_init())
     {
-#if defined(ROCKBOX_HAS_LOGF) && defined(LOGF_ENABLE)
+#ifdef ROCKBOX_HAS_LOGF
         syn_info();
 #endif
 
-        syn_status = STATUS_READY;
+        syn_status = 1;
 
         /* enable interrupts */
         GPIOD_INT_LEV &= ~0x2;
@@ -544,24 +86,25 @@ void button_int(void)
 
     int_btn = BUTTON_NONE;
 
-    if (syn_status == STATUS_READY)
+    if (syn_status)
     {
         /* disable interrupt while we read the touchpad */
-        GPIOD_INT_EN &= ~0x2;
+        GPIOD_INT_EN  &= ~0x2;
+        GPIOD_INT_CLR |=  0x2;
 
         val = syn_read_device(data, 4);
         if (val > 0)
         {
             val = data[0] & 0xff;      /* packet header */
             id = (data[1] >> 4) & 0xf; /* packet id */
-#if defined(LOGF_ENABLE)
+
             logf("button_read_device...");
             logf("  data[0] = 0x%08x", data[0]);
             logf("  data[1] = 0x%08x", data[1]);
             logf("  data[2] = 0x%08x", data[2]);
             logf("  data[3] = 0x%08x", data[3]);
-#endif
-            if ((val == BUTTONS_HEADER) && (id == BUTTONS_ID))
+
+            if ((val == MEP_BUTTON_HEADER) && (id == MEP_BUTTON_ID))
             {
                 /* Buttons packet - touched one of the 5 "buttons" */
                 if (data[1] & 0x1)
@@ -577,22 +120,21 @@ void button_int(void)
 
                 /* An Absolute packet should follow which we ignore */
                 val = syn_read_device(data, 4);
-#if defined(LOGF_ENABLE)
+
                 logf("  int_btn = 0x%04x", int_btn);
-#endif            
             }
-            else if (val == ABSOLUTE_HEADER)
+            else if (val == MEP_ABSOLUTE_HEADER)
             {
                 /* Absolute packet - the finger is on the vertical strip.
                    Position ranges from 1-4095, with 1 at the bottom. */
                 val = ((data[1] >> 4) << 8) | data[2]; /* position */
-#if defined(LOGF_ENABLE)                
+
                 logf(" pos %d", val);
                 logf(" z %d", data[3]);
                 logf(" finger %d", data[1] & 0x1);
                 logf(" gesture %d", data[1] & 0x2);
                 logf(" RelPosVld %d", data[1] & 0x4);
-#endif                
+
                 if(data[1] & 0x1)  /* if finger on touch strip */
                 {
                     if ((val > 0) && (val <= 1365))
@@ -607,7 +149,6 @@ void button_int(void)
 
         /* re-enable interrupts */
         GPIOD_INT_LEV &= ~0x2;
-        GPIOD_INT_CLR |=  0x2;
         GPIOD_INT_EN  |=  0x2;
     }
 }