imx233: add automatic battery conversion using delay channel, make 5V a virtual channel since it has a builtin divider

fuze+: use 5V virtual channel

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@30982 a1c6a512-1295-4272-9138-f99709370657

3 files changed, 22 insertions, 7 deletions

diff --git a/firmware/target/arm/imx233/adc-imx233.c b/firmware/target/arm/imx233/adc-imx233.c
index b23e57f9b4..5e9717b922 100644
--- a/firmware/target/arm/imx233/adc-imx233.c
+++ b/firmware/target/arm/imx233/adc-imx233.c
@@ -30,25 +30,37 @@
  * and channel 6 to vddio */
 static int pmos_chan, nmos_chan;
 static int battery_chan, vddio_chan;
+static int battery_delay_chan;
 
 void adc_init(void)
 {
     imx233_lradc_init();
+    /* reserve channels 6 for vddio and 7 for battery (special for conversion) */
     battery_chan = 7;
     vddio_chan = 6;
     imx233_lradc_reserve_channel(battery_chan);
     imx233_lradc_reserve_channel(vddio_chan);
-    
+    /* reserve any channels for PMOS and NMOS */
     pmos_chan = imx233_lradc_acquire_channel(TIMEOUT_NOBLOCK);
     if(pmos_chan < 0) panicf("No LRADC channel for PMOS !");
     nmos_chan = imx233_lradc_acquire_channel(TIMEOUT_NOBLOCK);
     if(nmos_chan < 0) panicf("No LRADC channel for NMOS !");
 
-    // setup them
+    /* setup them for the simplest use: no accumulation, no division*/
     imx233_lradc_setup_channel(battery_chan, false, false, 0, HW_LRADC_CHANNEL_BATTERY);
     imx233_lradc_setup_channel(vddio_chan, false, false, 0, HW_LRADC_CHANNEL_VDDIO);
     imx233_lradc_setup_channel(nmos_chan, false, false, 0, HW_LRADC_CHANNEL_NMOS_THIN);
     imx233_lradc_setup_channel(pmos_chan, false, false, 0, HW_LRADC_CHANNEL_PMOS_THIN);
+    /* setup delay channel for battery for automatic reading and scaling */
+    battery_delay_chan = 0;
+    imx233_lradc_reserve_delay(battery_delay_chan);
+    /* setup delay to trigger battery channel and retrigger itself.
+     * The counter runs at 2KHz so a delay of 200 will trigger 10
+     * conversions per seconds */
+    imx233_lradc_setup_delay(battery_delay_chan, 1 << battery_chan,
+        1 << battery_delay_chan, 0, 200);
+    /* enable automatic conversion, use Li-Ion type battery */
+    imx233_lradc_setup_battery_conversion(true, HW_LRADC_CONVERSION__SCALE_FACTOR__LI_ION);
 }
 
 int adc_read_physical_ex(int virt)
@@ -56,8 +68,7 @@ int adc_read_physical_ex(int virt)
     imx233_lradc_clear_channel(virt);
     imx233_lradc_kick_channel(virt);
     imx233_lradc_wait_channel(virt);
-    int v = imx233_lradc_read_channel(virt);
-    return v;
+    return imx233_lradc_read_channel(virt);
 }
 
 int adc_read_physical(int src)
@@ -75,9 +86,12 @@ unsigned short adc_read_virtual(int c)
     switch(c)
     {
         case IMX233_ADC_BATTERY:
-            return adc_read_physical_ex(battery_chan);
+            return /*imx233_lradc_read_battery_voltage()*/adc_read_physical_ex(battery_chan);
         case IMX233_ADC_VDDIO:
             return adc_read_physical_ex(vddio_chan);
+        case IMX233_ADC_5V:
+            /* channel 15 5V has a 4:1 built it divider */
+            return adc_read_physical(HW_LRADC_CHANNEL_5V) * 4;
         case IMX233_ADC_DIE_TEMP:
             // do kelvin to celsius conversion
             return imx233_lradc_sense_die_temperature(nmos_chan, pmos_chan) - 273;
diff --git a/firmware/target/arm/imx233/adc-imx233.h b/firmware/target/arm/imx233/adc-imx233.h
index 6025fdcdf8..7468fbe3c3 100644
--- a/firmware/target/arm/imx233/adc-imx233.h
+++ b/firmware/target/arm/imx233/adc-imx233.h
@@ -29,6 +29,7 @@
 #define IMX233_ADC_BATTERY      -1 /* Battery voltage (mV) */
 #define IMX233_ADC_DIE_TEMP     -2 /* Die temperature (°C) */
 #define IMX233_ADC_VDDIO        -3 /* VddIO voltage (mV) */
+#define IMX233_ADC_5V           -4 /* Vdd5V voltage (mV) */
 
 /* Channel mapping */
 extern int imx233_adc_mapping[];
diff --git a/firmware/target/arm/imx233/sansa-fuzeplus/adc-fuzeplus.c b/firmware/target/arm/imx233/sansa-fuzeplus/adc-fuzeplus.c
index 757ec72519..2da440b170 100644
--- a/firmware/target/arm/imx233/sansa-fuzeplus/adc-fuzeplus.c
+++ b/firmware/target/arm/imx233/sansa-fuzeplus/adc-fuzeplus.c
@@ -26,7 +26,7 @@ int imx233_adc_mapping[] =
     [ADC_BATTERY] = IMX233_ADC_BATTERY,
     [ADC_DIE_TEMP] = IMX233_ADC_DIE_TEMP,
     [ADC_VDDIO] = IMX233_ADC_VDDIO,
-    [ADC_5V] = HW_LRADC_CHANNEL_5V,
+    [ADC_5V] = IMX233_ADC_5V,
 };
 
 const char *imx233_adc_channel_name[] =
@@ -34,5 +34,5 @@ const char *imx233_adc_channel_name[] =
     "Battery(mV)",
     "Die temperature(°C)",
     "VddIO",
-    "5V",
+    "Vdd5V",
 };