1 files changed, 136 insertions, 0 deletions

diff --git a/firmware/target/arm/imx31/gigabeat-s/adc-gigabeat-s.c b/firmware/target/arm/imx31/gigabeat-s/adc-gigabeat-s.c
new file mode 100644
index 0000000000..52293228f8
--- /dev/null
+++ b/firmware/target/arm/imx31/gigabeat-s/adc-gigabeat-s.c
@@ -0,0 +1,136 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2008 by Michael Sevakis
+ *
+ * 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 "mc13783.h"
+#include "adc.h"
+#include "adc-target.h"
+#include "kernel.h"
+
+/* Do this so we may read all channels in a single SPI message */
+static const unsigned char reg_array[4] =
+{
+    MC13783_ADC2,
+    MC13783_ADC2,
+    MC13783_ADC2,
+    MC13783_ADC2,
+};
+
+static uint32_t channels[2][4];
+static struct wakeup adc_wake;
+static struct mutex adc_mtx;
+static long last_adc_read[2]; /* One for each input group */
+
+/* Read 10-bit ADC channel */
+unsigned short adc_read(int channel)
+{
+    uint32_t data;
+    int input_select;
+
+    if ((unsigned)channel >= NUM_ADC_CHANNELS)
+        return ADC_READ_ERROR;
+
+    input_select = channel >> 3;
+
+    mutex_lock(&adc_mtx);
+
+    /* Limit the traffic through here */
+    if (current_tick != last_adc_read[input_select])
+    {
+        /* Keep enable, start conversion, increment from channel 0,
+         * increment from channel 4 */
+        uint32_t adc1 = MC13783_ADEN | MC13783_ASC |
+                        (0 << MC13783_ADA1_POS) | (4 << MC13783_ADA2_POS);
+
+        if (input_select == 1)
+            adc1 |= MC13783_ADSEL; /* 2nd set of inputs */
+
+        /* Start conversion */
+        mc13783_write(MC13783_ADC1, adc1);
+
+        /* Wait for done signal */
+        wakeup_wait(&adc_wake, TIMEOUT_BLOCK);
+
+        /* Read all 8 channels that are converted - two channels in each
+         * word. */
+        mc13783_read_regset(reg_array, channels[input_select], 4);
+
+        last_adc_read[input_select] = current_tick;
+    }
+
+    data = channels[input_select][channel & 3];
+
+    mutex_unlock(&adc_mtx);
+
+    /* Channels 0-3/8-11 in ADD1, 4-7/12-15 in ADD2 */
+    return (channel & 4) ?
+        ((data & MC13783_ADD2) >> MC13783_ADD2_POS) :
+        ((data & MC13783_ADD1) >> MC13783_ADD1_POS);
+}
+
+bool adc_enable_channel(int channel, bool enable)
+{
+    uint32_t bit, mask;
+
+    switch (channel)
+    {
+    case ADC_CHARGER_CURRENT:
+        mask = MC13783_CHRGICON;
+        break;
+
+    case ADC_BATTERY_TEMP:
+        mask = MC13783_RTHEN;
+        break;
+
+    default:
+        return false;
+    }
+
+    bit = enable ? mask : 0;
+
+    return mc13783_write_masked(MC13783_ADC0, bit, mask)
+                != MC13783_DATA_ERROR;
+}
+
+/* Called by mc13783 interrupt thread when conversion is complete */
+void adc_done(void)
+{
+    wakeup_signal(&adc_wake);
+}
+
+void adc_init(void) 
+{
+    wakeup_init(&adc_wake);
+    mutex_init(&adc_mtx);
+
+    /* Init so first reads get data */
+    last_adc_read[0] = last_adc_read[1] = current_tick-1;
+
+    /* Enable increment-by-read, turn off extra conversions. */
+    mc13783_write(MC13783_ADC0, MC13783_ADINC2 | MC13783_ADINC1);
+
+    /* Enable ADC, set multi-channel mode */
+    mc13783_write(MC13783_ADC1, MC13783_ADEN);
+
+    /* Enable ADCDONE event */
+    mc13783_write(MC13783_INTERRUPT_STATUS0, MC13783_ADCDONEI);
+    mc13783_enable_event(MC13783_ADCDONE_EVENT);
+}