--- /dev/null
+++ kernel-power/drivers/power/rx51_battery.c
-@@ -0,0 +1,216 @@
+@@ -0,0 +1,263 @@
+/*
+ rx51_battery.c - Nokia RX-51 battery driver
+ Copyright (C) 2012 Pali Rohár <pali.rohar@gmail.com>
+ struct power_supply bat;
+};
+
-+/* Read ADCIN channel value, code copied from maemo kernel */
++/*
++ Read ADCIN channel value, code copied from maemo kernel
++ */
+static int rx51_battery_read_adc(int channel)
+{
+ struct twl4030_madc_request req;
+ req.type = TWL4030_MADC_WAIT;
+
+ if (twl4030_madc_conversion(&req) > 0)
-+ return (u16)req.rbuf[channel];
++ return req.rbuf[channel];
+ else
+ return -ENODATA;
+}
+
-+/* Read ADCIN channel 12 (voltage) and convert RAW value to micro voltage */
-+/* This conversion formula was extracted from maemo program bsi-read */
++/*
++ Read ADCIN channel 12 (voltage) and convert RAW value to micro voltage
++ This conversion formula was extracted from maemo program bsi-read
++ */
+static int rx51_battery_read_voltage(struct rx51_device_info *di)
+{
+ int voltage = rx51_battery_read_adc(12);
+ return 1000 * (10000 * voltage / 1705);
+}
+
-+/* Conversation table based on experimental data */
-+/* Usage: rx51_temp_table[rx51_temp_first - Celsius value] = lowest RAW value */
-+static int rx51_temp_first = 48;
-+static int rx51_temp_table[] = {
-+ 30, 31, 32, 33, 34, 35, 36, 38, 39, 40, 42, 43, 45, 47,
-+ 48, 50, 51, 53, 55, 57, 59, 61, 63, 66, 69, 72, 74, 76,
-+ 80, 83, 86, 90, 93, 96, 100, 105, 109, 114, 119, 124, 130, 136,
-+ 142, 148, 155, 161, 166, 177, 184, 193, 202, 213, 222, 230, 243, 255,
-+ 268, 280
++/*
++ Temperature look-up tables
++ TEMP = (1/(t1 + 1/298) - 273.15)
++ Where t1 = (1/B) * ln((RAW_ADC_U * 2.5)/(R * I * 255))
++ Formula is based on experimental data, RX-51 CAL data, maemo program bme
++ and formula from da9052 driver with values R = 100, B = 3380, I = 0.00671
++ */
++
++/*
++ Table1 (temperature for first 25 RAW values)
++ Usage: TEMP = rx51_temp_table1[RAW]
++ RAW is between 1 and 24
++ TEMP is between 201 C and 55 C
++ */
++static u8 rx51_temp_table1[] = {
++ 255, 201, 159, 138, 124, 114, 106, 99, 94, 89, 85, 82, 78, 75,
++ 73, 70, 68, 66, 64, 62, 61, 59, 57, 56, 55
++};
++
++/*
++ Table2 (lowest RAW value for temperature)
++ Usage: RAW = rx51_temp_table2[TEMP-rx51_temp_table2_first]
++ TEMP is between 53 C and -32 C
++ RAW is between 25 and 993
++ */
++static u8 rx51_temp_table2_first = 53;
++static u16 rx51_temp_table2[] = {
++ 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 39,
++ 40, 41, 43, 44, 46, 48, 49, 51, 53, 55, 57, 59, 61, 64,
++ 66, 69, 71, 74, 77, 80, 83, 86, 90, 94, 97, 101, 106, 110,
++ 115, 119, 125, 130, 136, 141, 148, 154, 161, 168, 176, 184, 202, 211,
++ 221, 231, 242, 254, 266, 279, 293, 308, 323, 340, 357, 375, 395, 415,
++ 437, 460, 485, 511, 539, 568, 600, 633, 669, 706, 747, 790, 836, 885,
++ 937, 993
+};
+
-+/* Read ADCIN channel 0 (battery temp) and convert value to tenths of Celsius */
-+/* Try to find lowest temperature value for raw value in table */
++/*
++ Read ADCIN channel 0 (battery temp) and convert value to tenths of Celsius
++ Use Temperature look-up tables for conversation
++ */
+static int rx51_battery_read_temperature(struct rx51_device_info *di)
+{
+ int min = 0;
-+ int max = ARRAY_SIZE(rx51_temp_table)-1;
-+ int temperature = rx51_battery_read_adc(0);
++ int max = ARRAY_SIZE(rx51_temp_table2)-1;
++ int raw = rx51_battery_read_adc(0);
++
++ /* Zero and negative values are undefined */
++ if (raw <= 0)
++ return INT_MAX;
++
++ /* ADC channels are 10 bit, higher value are undefined */
++ if (raw >= (1 << 10))
++ return INT_MIN;
++
++ /* First check for temperature in first direct table */
++ if (raw < ARRAY_SIZE(rx51_temp_table1))
++ return rx51_temp_table1[raw];
+
-+ if (temperature < 0)
-+ return temperature;
-+ if (temperature < rx51_temp_table[min])
-+ return rx51_temp_first-min+1;
-+ if (temperature > rx51_temp_table[max])
-+ return rx51_temp_first-max-1;
++ /* Possible correct values which are not in tables */
++ if (raw < rx51_temp_table2[min])
++ return rx51_temp_table2_first-min;
++ if (raw > rx51_temp_table2[max])
++ return rx51_temp_table2_first-max;
+
++ /* Binary search RAW value in second inverse table */
+ while (max-min > 1) {
+ int mid = (max+min)/2;
-+ if (rx51_temp_table[mid] <= temperature)
++ if (rx51_temp_table2[mid] <= raw)
+ min = mid;
-+ else if (rx51_temp_table[mid] > temperature)
++ else if (rx51_temp_table2[mid] > raw)
+ max = mid;
-+ if (rx51_temp_table[mid] == temperature)
++ if (rx51_temp_table2[mid] == raw)
+ break;
+ }
+
-+ return (rx51_temp_first - min) * 100;
++ return (rx51_temp_table2_first - min) * 100;
+}
+
-+/* Read ADCIN channel 4 (BSI) and convert RAW value to micro Ah */
-+/* This conversion formula was extracted from maemo program bsi-read */
++/*
++ Read ADCIN channel 4 (BSI) and convert RAW value to micro Ah
++ This conversion formula was extracted from maemo program bsi-read
++ */
+static int rx51_battery_read_capacity(struct rx51_device_info *di)
+{
+ int capacity = rx51_battery_read_adc(4);
+ return 1280 * (1200 * capacity)/(1024 - capacity);
+}
+
-+/* Return power_supply property */
++/*
++ Return power_supply property
++ */
+static int rx51_battery_get_property(struct power_supply *psy,
+ enum power_supply_property psp,
+ union power_supply_propval *val)
+ return -EINVAL;
+ }
+
-+ if (val->intval < 0)
-+ return val->intval;
++ if (val->intval == INT_MAX || val->intval == INT_MIN)
++ return -EINVAL;
+
+ return 0;
+}
projects / kernel-power / commitdiff