D2: Implement battery voltage readout from PCF50606 (levels not yet calibrated). Adjust I2C delay to ensure this also works when boosted.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@17085 a1c6a512-1295-4272-9138-f99709370657

3 files changed, 35 insertions, 16 deletions

diff --git a/firmware/export/config-cowond2.h b/firmware/export/config-cowond2.h
index 74cf90eac4..3938bd0739 100644
--- a/firmware/export/config-cowond2.h
+++ b/firmware/export/config-cowond2.h
@@ -105,10 +105,6 @@
 #define BATTERY_CAPACITY_INC 50   /* capacity increment */
 #define BATTERY_TYPES_COUNT  1    /* only one type */
 
-/* define this if the unit should not shut down on low battery. */
-/* TODO: this is temporary until battery monitoring implemented */
-#define NO_LOW_BATTERY_SHUTDOWN
-
 #ifndef SIMULATOR
 
 /* Define this if you have a TCC7801 */
diff --git a/firmware/target/arm/i2c-telechips.c b/firmware/target/arm/i2c-telechips.c
index e3e8fd3d33..8e5db2f26f 100644
--- a/firmware/target/arm/i2c-telechips.c
+++ b/firmware/target/arm/i2c-telechips.c
@@ -23,7 +23,7 @@
 #include "i2c-target.h"
 
 /* arbitrary delay loop */
-#define DELAY  do { int _x; for(_x=0;_x<20;_x++);} while (0)
+#define DELAY  do { int _x; for(_x=0;_x<40;_x++);} while (0)
 
 static struct mutex i2c_mtx;
 
diff --git a/firmware/target/arm/tcc780x/cowond2/powermgmt-cowond2.c b/firmware/target/arm/tcc780x/cowond2/powermgmt-cowond2.c
index b3572307e9..71e4e325e8 100644
--- a/firmware/target/arm/tcc780x/cowond2/powermgmt-cowond2.c
+++ b/firmware/target/arm/tcc780x/cowond2/powermgmt-cowond2.c
@@ -21,39 +21,62 @@
 #include "adc.h"
 #include "powermgmt.h"
 #include "kernel.h"
+#include "pcf50606.h"
 
 unsigned short current_voltage = 3910;
+
 const unsigned short battery_level_dangerous[BATTERY_TYPES_COUNT] =
 {
-    0
+    /* FIXME: calibrate value */
+    3380
 };
 
 const unsigned short battery_level_shutoff[BATTERY_TYPES_COUNT] =
 {
-    0
+    /* FIXME: calibrate value */
+    3300
 };
 
 /* voltages (millivolt) of 0%, 10%, ... 100% when charging disabled */
 const unsigned short percent_to_volt_discharge[BATTERY_TYPES_COUNT][11] =
 {
-    { 100, 300, 400, 500, 600, 700, 800, 900, 1000, 1200, 1320 },
+    /* FIXME: calibrate values. Table is "inherited" from iPod-PCF / H100 */
+    { 3370, 3650, 3700, 3740, 3780, 3820, 3870, 3930, 4000, 4080, 4160 }
 };
 
+#if CONFIG_CHARGING
 /* voltages (millivolt) of 0%, 10%, ... 100% when charging enabled */
 const unsigned short percent_to_volt_charge[11] =
 {
-    100, 300, 400, 500, 600, 700, 800, 900, 1000, 1200, 1320,
+    /* FIXME: calibrate values. Table is "inherited" from iPod-PCF / H100 */
+    { 3370, 3650, 3700, 3740, 3780, 3820, 3870, 3930, 4000, 4080, 4160 }
 };
+#endif /* CONFIG_CHARGING */
+
+#define BATTERY_SCALE_FACTOR 6000
+/* full-scale ADC readout (2^10) in millivolt */
 
-void read_battery_inputs(void)
-{
-    #warning function not implemented
-}
-    
 /* Returns battery voltage from ADC [millivolts] */
 unsigned int battery_adc_voltage(void)
 {
-    #warning function not implemented
-    return 0;
+    static unsigned last_tick = 0;
+
+    if (TIME_BEFORE(last_tick+HZ, current_tick))
+    {
+        int adc_val, irq_status;
+        unsigned char buf[2];
+
+        irq_status = disable_interrupt_save(IRQ_FIQ_DISABLED);
+        pcf50606_write(PCF5060X_ADCC2, 0x1);
+        pcf50606_read_multiple(PCF5060X_ADCS1, buf, 2);
+        restore_interrupt(irq_status);
+
+        adc_val = (buf[0]<<2) | (buf[1] & 3); //ADCDAT1H+ADCDAT1L
+        current_voltage = (adc_val * BATTERY_SCALE_FACTOR) >> 10;
+
+        last_tick = current_tick;
+    }
+
+    return current_voltage;
 }