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

1 files changed, 482 insertions, 0 deletions

diff --git a/firmware/drivers/synaptics-mep.c b/firmware/drivers/synaptics-mep.c
new file mode 100644
index 0000000..44b1860
--- /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