From: Michael Büsch Date: Sun, 22 Aug 2010 14:45:08 +0000 (+0000) Subject: n810: Add basic battery management driver X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=8c43d37dbb201841b5b43f93061cd3e127d7183d;p=openwrt%2Fstaging%2Fldir.git n810: Add basic battery management driver SVN-Revision: 22760 --- diff --git a/target/linux/omap24xx/config-2.6.35 b/target/linux/omap24xx/config-2.6.35 index b5ac7a5ad2..0294b4b72b 100644 --- a/target/linux/omap24xx/config-2.6.35 +++ b/target/linux/omap24xx/config-2.6.35 @@ -351,6 +351,7 @@ CONFIG_MTD_ONENAND_OTP=y # CONFIG_MTD_ONENAND_VERIFY_WRITE is not set # CONFIG_MTD_ROOTFS_ROOT_DEV is not set # CONFIG_MTD_ROOTFS_SPLIT is not set +CONFIG_N810BM=y CONFIG_NAMESPACES=y CONFIG_NEED_DMA_MAP_STATE=y CONFIG_NETDEV_10000=y diff --git a/target/linux/omap24xx/patches-2.6.35/900-n810-battery-management.patch b/target/linux/omap24xx/patches-2.6.35/900-n810-battery-management.patch new file mode 100644 index 0000000000..fcb46c0e3b --- /dev/null +++ b/target/linux/omap24xx/patches-2.6.35/900-n810-battery-management.patch @@ -0,0 +1,489 @@ +--- + 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 ++ * ++ * 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 ++#include ++#include ++#include ++#include ++#include ++#include ++ ++#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")