--- /dev/null
+---
+ arch/arm/mach-omap2/board-n8x0.c | 13 +
+ drivers/cbus/Kconfig | 12 +
+ drivers/cbus/Makefile | 1
+ drivers/cbus/n810bm.c | 396 +++++++++++++++++++++++++++++++++++++++
+ drivers/cbus/retu.c | 4
+ drivers/cbus/retu.h | 2
+ 6 files changed, 425 insertions(+), 3 deletions(-)
+
+--- linux-2.6.35.3.orig/drivers/cbus/Kconfig
++++ linux-2.6.35.3/drivers/cbus/Kconfig
+@@ -94,4 +94,16 @@ config CBUS_RETU_HEADSET
+ to Retu/Vilma. Detection state and events are exposed through
+ sysfs.
+
++config N810BM
++ depends on CBUS_RETU && CBUS_TAHVO
++ tristate "Nokia n810 battery management"
++ ---help---
++ Nokia n810 device battery management.
++
++ WARNING: This driver is based on reverse engineered information.
++ It is possibly dangerous to use this software.
++ Use this software at your own risk!
++
++ If unsure, say N.
++
+ endmenu
+--- linux-2.6.35.3.orig/drivers/cbus/Makefile
++++ linux-2.6.35.3/drivers/cbus/Makefile
+@@ -12,3 +12,4 @@ obj-$(CONFIG_CBUS_RETU_WDT) += retu-wdt.
+ obj-$(CONFIG_CBUS_TAHVO_USER) += tahvo-user.o
+ obj-$(CONFIG_CBUS_RETU_USER) += retu-user.o
+ obj-$(CONFIG_CBUS_RETU_HEADSET) += retu-headset.o
++obj-$(CONFIG_N810BM) += n810bm.o
+--- /dev/null
++++ linux-2.6.35.3/drivers/cbus/n810bm.c
+@@ -0,0 +1,396 @@
++/*
++ * Nokia n810 battery management
++ *
++ * WARNING: This driver is based on reverse engineered information.
++ * It is possibly dangerous to use this software.
++ * Use this software at your own risk!
++ *
++ * Copyright (c) 2010 Michael Buesch <mb@bu3sch.de>
++ *
++ * 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 program is distributed in the hope that it will be useful,
++ * but WITHOUT ANY WARRANTY; without even the implied warranty of
++ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
++ * GNU General Public License for more details.
++ */
++
++#include <linux/module.h>
++#include <linux/device.h>
++#include <linux/platform_device.h>
++#include <linux/slab.h>
++#include <linux/spinlock.h>
++#include <linux/timer.h>
++#include <linux/reboot.h>
++
++#include "retu.h"
++#include "tahvo.h"
++
++
++#define N810BM_CHECK_INTERVAL (HZ * 5)
++#define N810BM_MIN_VOLTAGE_THRES 3400 /* Absolute minimum voltage threshold */
++/* FIXME: Not sure about the actual value of the low threshold, yet.
++ * We must give userspace a chance to detect undervoltage and perform
++ * a clean shutdown, before we flip the big switch. */
++
++
++/* Battery related retu ADC channels */
++#define RETU_ADC_BSI 0x01 /* Battery Size Indicator */
++#define RETU_ADC_BATTVOLT 0x08 /* Battery voltage measurement */
++
++/* RETU_ADC_BSI
++ * The battery size indicator ADC measures the resistance between
++ * the battery BSI pin and ground. This is used to detect the battery
++ * capacity, as the BSI resistor is related to capacity.
++ *
++ * Manually measured lookup table.
++ * Hard to measure, thus not very accurate.
++ *
++ * Resistance | ADC value
++ * ========================
++ * 120k | 0x3AC
++ * 110k | 0x37C
++ * 100k | 0x351
++ * 90k | 0x329
++ */
++
++/* RETU_ADC_BATTVOLT
++ * Manually measured lookup table.
++ * Hard to measure, thus not very accurate.
++ *
++ * Voltage | ADC value
++ * =====================
++ * 2.80V | 0x037
++ * 2.90V | 0x05E
++ * 3.00V | 0x090
++ * 3.10V | 0x0A4
++ * 3.20V | 0x0CC
++ * 3.30V | 0x0EF
++ * 3.40V | 0x115
++ * 3.50V | 0x136
++ * 3.60V | 0x15C
++ * 3.70V | 0x187
++ * 3.80V | 0x1A5
++ * 3.90V | 0x1C9
++ * 4.00V | 0x1ED
++ * 4.10V | 0x212
++ * 4.20V | 0x236
++ */
++
++
++enum n810bm_capacity {
++ N810BM_CAP_UNKNOWN = 0,
++ N810BM_CAP_1500MAH = 1500, /* 1500 mAh battery */
++};
++
++struct n810bm {
++ struct platform_device *pdev;
++ enum n810bm_capacity capacity;
++ struct timer_list check_timer;
++ spinlock_t lock;
++};
++
++
++static NORET_TYPE void n810bm_emergency(struct n810bm *bm, const char *message) ATTRIB_NORET;
++static void n810bm_emergency(struct n810bm *bm, const char *message)
++{
++ printk(KERN_EMERG "Nokia n810 battery management fatal fault: %s\n", message);
++ /* Force a hard shutdown. */
++ machine_power_off();
++ panic("n810bm: Failed to halt machine in emergency state\n");
++}
++
++#if 0
++static u16 retu_read(struct n810bm *bm, unsigned int reg)
++{
++ int ret;
++ unsigned long flags;
++
++ spin_lock_irqsave(&retu_lock, flags);
++ ret = retu_read_reg(reg);
++ spin_unlock_irqrestore(&retu_lock, flags);
++ if (ret < 0 || ret > 0xFFFF)
++ n810bm_emergency(bm, "retu_read");
++
++ return ret;
++}
++#endif
++
++static void retu_maskset(struct n810bm *bm, unsigned int reg, u16 mask, u16 set)
++{
++ int ret;
++ unsigned long flags;
++ u16 value;
++
++ spin_lock_irqsave(&retu_lock, flags);
++ if (~mask) {
++ ret = retu_read_reg(reg);
++ if (ret < 0 || ret > 0xFFFF)
++ goto fatal_unlock;
++ value = ret;
++ } else
++ value = 0;
++ value &= ~mask;
++ value |= set;
++ ret = retu_write_reg(reg, value);
++ if (ret)
++ goto fatal_unlock;
++ spin_unlock_irqrestore(&retu_lock, flags);
++
++ return;
++
++fatal_unlock:
++ spin_unlock_irqrestore(&retu_lock, flags);
++ n810bm_emergency(bm, "retu_maskset");
++}
++
++static inline void retu_write(struct n810bm *bm, unsigned int reg, u16 value)
++{
++ return retu_maskset(bm, reg, 0xFFFF, value);
++}
++
++static int retu_adc_average(struct n810bm *bm, unsigned int chan,
++ unsigned int nr_passes)
++{
++ unsigned int i, value = 0;
++ int ret;
++
++ if (WARN_ON(!nr_passes))
++ return 0;
++ for (i = 0; i < nr_passes; i++) {
++ ret = retu_read_adc(chan);
++ if (ret < 0)
++ return ret;
++ value += ret;
++ }
++ value /= nr_passes;
++
++ return value;
++}
++
++/* Measure the battery voltage. Returns the value in mV (or negative value on error). */
++static int n810bm_measure_batt_voltage(struct n810bm *bm)
++{
++ int adc;
++ unsigned int mv;
++ const unsigned int scale = 1000;
++
++ adc = retu_adc_average(bm, RETU_ADC_BATTVOLT, 5);
++ if (adc < 0)
++ return adc;
++ if (adc <= 0x37)
++ return 2800;
++ mv = 2800 + ((adc - 0x37) * (((4200 - 2800) * scale) / (0x236 - 0x37))) / scale;
++
++ return mv;
++}
++
++/* Read the battery capacity via BSI pin. */
++static enum n810bm_capacity n810bm_read_batt_capacity(struct n810bm *bm)
++{
++ int adc;
++ const unsigned int hyst = 16;
++
++ adc = retu_adc_average(bm, RETU_ADC_BSI, 5);
++ if (adc < 0)
++ return N810BM_CAP_UNKNOWN;
++
++ if (adc >= 0x3AC - hyst && adc <= 0x3AC + hyst)
++ return N810BM_CAP_1500MAH;
++
++ return N810BM_CAP_UNKNOWN;
++}
++
++struct mv2p {
++ unsigned int mv;
++ unsigned int p;
++};
++
++/* Convert a battery voltage (in mV) to percentage. */
++static unsigned int n810bm_mvolt2percent(unsigned int mv)
++{
++ /* FIXME: Create a correct table. */
++ static const struct mv2p table[] = {
++ { .mv = 4200, .p = 100, },
++ { .mv = 4150, .p = 90, },
++ { .mv = 4100, .p = 80, },
++ { .mv = 4050, .p = 70, },
++ { .mv = 4000, .p = 60, },
++ { .mv = 3950, .p = 50, },
++ { .mv = 3900, .p = 40, },
++ { .mv = 3850, .p = 30, },
++ { .mv = 3800, .p = 20, },
++ { .mv = 3750, .p = 10, },
++ { .mv = 3700, .p = 0, },
++ };
++ const struct mv2p *e;
++ unsigned int i;
++
++ for (i = 0; i < ARRAY_SIZE(table); i++) {
++ e = &table[i];
++ if (mv >= e->mv)
++ return e->p;
++ }
++
++ return 0;
++}
++
++static void n810bm_check_timer(unsigned long data)
++{
++ struct n810bm *bm = (struct n810bm *)data;
++ unsigned long flags;
++ int mv;
++
++ spin_lock_irqsave(&bm->lock, flags);
++
++ mv = n810bm_measure_batt_voltage(bm);
++ if (mv < 0)
++ n810bm_emergency(bm, "check timer: Failed to measure");
++ if (mv < N810BM_MIN_VOLTAGE_THRES)
++ n810bm_emergency(bm, "check timer: Minimum voltage threshold reached");
++
++ mod_timer(&bm->check_timer, round_jiffies(jiffies + N810BM_CHECK_INTERVAL));
++ spin_unlock_irqrestore(&bm->lock, flags);
++
++ return;
++}
++
++static ssize_t n810bm_attr_charge_show(struct device *dev,
++ struct device_attribute *attr,
++ char *buf)
++{
++ struct platform_device *pdev = to_platform_device(dev);
++ struct n810bm *bm = platform_get_drvdata(pdev);
++ int err = -ENODEV;
++ ssize_t count = 0;
++ int millivolt;
++
++ spin_lock_irq(&bm->lock);
++ millivolt = n810bm_measure_batt_voltage(bm);
++ if (millivolt >= 0) {
++ count = snprintf(buf, PAGE_SIZE, "%u\n",
++ n810bm_mvolt2percent(millivolt));
++ err = 0;
++ }
++ spin_unlock_irq(&bm->lock);
++
++ return err ? err : count;
++}
++static DEVICE_ATTR(batt_charge, 0444, n810bm_attr_charge_show, NULL);
++
++static ssize_t n810bm_attr_capacity_show(struct device *dev,
++ struct device_attribute *attr,
++ char *buf)
++{
++ struct platform_device *pdev = to_platform_device(dev);
++ struct n810bm *bm = platform_get_drvdata(pdev);
++ ssize_t count;
++
++ spin_lock_irq(&bm->lock);
++ count = snprintf(buf, PAGE_SIZE, "%u\n",
++ (unsigned int)bm->capacity);
++ spin_unlock_irq(&bm->lock);
++
++ return count;
++}
++static DEVICE_ATTR(batt_capacity, 0444, n810bm_attr_capacity_show, NULL);
++
++static void n810bm_hw_exit(struct n810bm *bm)
++{
++ retu_write(bm, RETU_REG_ADCSCR, 0);
++}
++
++static int n810bm_hw_init(struct n810bm *bm)
++{
++ retu_write(bm, RETU_REG_ADCSCR, 0);
++
++ bm->capacity = n810bm_read_batt_capacity(bm);
++ if (bm->capacity == N810BM_CAP_UNKNOWN) {
++ dev_err(&bm->pdev->dev, "Unknown battery detected");
++ return -ENODEV;
++ }
++ dev_info(&bm->pdev->dev, "Detected %u mAh battery\n",
++ (unsigned int)bm->capacity);
++
++ return 0;
++}
++
++static int __devinit n810bm_probe(struct platform_device *pdev)
++{
++ struct n810bm *bm;
++ int err;
++
++ bm = kzalloc(sizeof(*bm), GFP_KERNEL);
++ if (!bm)
++ return -ENOMEM;
++ bm->pdev = pdev;
++ platform_set_drvdata(pdev, bm);
++ spin_lock_init(&bm->lock);
++ setup_timer(&bm->check_timer, n810bm_check_timer, (unsigned long)bm);
++
++ err = n810bm_hw_init(bm);
++ if (err)
++ goto err_free;
++ err = device_create_file(&pdev->dev, &dev_attr_batt_charge);
++ if (err)
++ goto err_exit;
++ err = device_create_file(&pdev->dev, &dev_attr_batt_capacity);
++ if (err)
++ goto err_rem_charge;
++
++ mod_timer(&bm->check_timer, round_jiffies(jiffies + N810BM_CHECK_INTERVAL));
++
++ dev_info(&pdev->dev, "Battery management initialized");
++
++ return 0;
++
++err_rem_charge:
++ device_remove_file(&pdev->dev, &dev_attr_batt_charge);
++err_exit:
++ n810bm_hw_exit(bm);
++err_free:
++ kfree(bm);
++ platform_set_drvdata(pdev, NULL);
++ return err;
++}
++
++static int __devexit n810bm_remove(struct platform_device *pdev)
++{
++ struct n810bm *bm = platform_get_drvdata(pdev);
++
++ del_timer_sync(&bm->check_timer);
++ device_remove_file(&pdev->dev, &dev_attr_batt_capacity);
++ device_remove_file(&pdev->dev, &dev_attr_batt_charge);
++ n810bm_hw_exit(bm);
++
++ kfree(bm);
++ platform_set_drvdata(pdev, NULL);
++
++ return 0;
++}
++
++static struct platform_driver n810bm_driver = {
++ .remove = __devexit_p(n810bm_remove),
++ .driver = {
++ .name = "n810bm",
++ }
++};
++
++static int __init n810bm_modinit(void)
++{
++ return platform_driver_probe(&n810bm_driver, n810bm_probe);
++}
++module_init(n810bm_modinit);
++
++static void __exit n810bm_modexit(void)
++{
++ platform_driver_unregister(&n810bm_driver);
++}
++module_exit(n810bm_modexit);
++
++MODULE_DESCRIPTION("Nokia n810 battery management");
++MODULE_LICENSE("GPL");
++MODULE_AUTHOR("Michael Buesch");
+--- linux-2.6.35.3.orig/drivers/cbus/retu.c
++++ linux-2.6.35.3/drivers/cbus/retu.c
+@@ -85,10 +85,10 @@ int retu_read_reg(int reg)
+ *
+ * This function writes a value to the specified register
+ */
+-void retu_write_reg(int reg, u16 val)
++int retu_write_reg(int reg, u16 val)
+ {
+ BUG_ON(!retu_initialized);
+- cbus_write_reg(cbus_host, RETU_ID, reg, val);
++ return cbus_write_reg(cbus_host, RETU_ID, reg, val);
+ }
+
+ void retu_set_clear_reg_bits(int reg, u16 set, u16 clear)
+--- linux-2.6.35.3.orig/drivers/cbus/retu.h
++++ linux-2.6.35.3/drivers/cbus/retu.h
+@@ -58,7 +58,7 @@
+ #define MAX_RETU_IRQ_HANDLERS 16
+
+ int retu_read_reg(int reg);
+-void retu_write_reg(int reg, u16 val);
++int retu_write_reg(int reg, u16 val);
+ void retu_set_clear_reg_bits(int reg, u16 set, u16 clear);
+ int retu_read_adc(int channel);
+ int retu_request_irq(int id, void *irq_handler, unsigned long arg, char *name);
+--- linux-2.6.35.3.orig/arch/arm/mach-omap2/board-n8x0.c
++++ linux-2.6.35.3/arch/arm/mach-omap2/board-n8x0.c
+@@ -875,6 +875,17 @@ extern void n8x0_blizzard_init(void);
+ #define n8x0_blizzard_init() 0
+ #endif
+
++static struct platform_device n810_bm_device = {
++ .name = "n810bm",
++ .id = -1,
++};
++
++static void __init n810_bm_init(void)
++{
++ if (platform_device_register(&n810_bm_device))
++ BUG();
++}
++
+ static void __init n8x0_init_machine(void)
+ {
+ platform_device_register(&n8x0_cbus_device);
+@@ -901,6 +912,8 @@ static void __init n8x0_init_machine(voi
+ n8x0_onenand_init();
+ n8x0_mmc_init();
+ n8x0_usb_init();
++
++ n810_bm_init();
+ }
+
+ MACHINE_START(NOKIA_N800, "Nokia N800")
projects / openwrt / staging / neocturne.git / commitdiff