lkml.org 
[lkml]   [2007]   [Apr]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
SubjectRe: [PATCH 6/7] [RFC] ds2760 battery driver
On Thu, Apr 12, 2007 at 03:25:45AM +0400, Anton Vorontsov wrote:
> This is driver for batteries with ds2760 chip inside. Such batteries
> used in almost every HP iPaq and HTC PDAs/phones.

Changes:

- follow battery class changes (get rid of vast amount of macro-created
functions).

- cleanups based on comments by Randy Dunlap.


Subject: [PATCH] [take2] ds2760 battery driver


Signed-off-by: Anton Vorontsov <cbou@mail.ru>
---
drivers/battery/Kconfig | 7 +
drivers/battery/Makefile | 1 +
drivers/battery/ds2760_battery.c | 493 ++++++++++++++++++++++++++++++++++++++
include/linux/ds2760_battery.h | 32 +++
4 files changed, 533 insertions(+), 0 deletions(-)
create mode 100644 drivers/battery/ds2760_battery.c
create mode 100644 include/linux/ds2760_battery.h
diff --git a/drivers/battery/Kconfig b/drivers/battery/Kconfig
index c386593..0c14ae0 100644
--- a/drivers/battery/Kconfig
+++ b/drivers/battery/Kconfig
@@ -8,4 +8,11 @@ config BATTERY
Say Y here to enable generic battery status reporting in
the /sys filesystem.

+config BATTERY_DS2760
+ tristate "DS2760 battery driver (HP iPAQ & others)"
+ depends on BATTERY && W1
+ select W1_SLAVE_DS2760
+ help
+ Say Y here to enable support for batteries with ds2760 chip.
+
endmenu
diff --git a/drivers/battery/Makefile b/drivers/battery/Makefile
index a2239cb..9902513 100644
--- a/drivers/battery/Makefile
+++ b/drivers/battery/Makefile
@@ -1 +1,2 @@
obj-$(CONFIG_BATTERY) += battery.o
+obj-$(CONFIG_BATTERY_DS2760) += ds2760_battery.o
diff --git a/drivers/battery/ds2760_battery.c b/drivers/battery/ds2760_battery.c
new file mode 100644
index 0000000..d996994
--- /dev/null
+++ b/drivers/battery/ds2760_battery.c
@@ -0,0 +1,493 @@
+/*
+ * Driver for batteries with DS2760 chips inside.
+ *
+ * Copyright (c) 2007 Anton Vorontsov
+ * 2004 Matt Reimer
+ * 2004 Szabolcs Gyurko
+ *
+ * Use consistent with the GNU GPL is permitted,
+ * provided that this copyright notice is
+ * preserved in its entirety in all copies and derived works.
+ *
+ * Author: Anton Vorontsov <cbou@mail.ru>
+ * February 2007
+ *
+ * Matt Reimer <mreimer@vpop.net>
+ * April 2004, 2005
+ *
+ * Szabolcs Gyurko <szabolcs.gyurko@tlt.hu>
+ * September 2004
+ */
+
+#include <linux/module.h>
+#include <linux/param.h>
+#include <linux/jiffies.h>
+#include <linux/workqueue.h>
+#include <linux/pm.h>
+#include <linux/platform_device.h>
+#include <linux/ds2760_battery.h>
+
+#include "../w1/w1.h"
+#include "../w1/slaves/w1_ds2760.h"
+
+struct ds2760_device_info {
+ struct battery_info *bi;
+
+ /* DS2760 data, valid after calling ds2760_battery_read_status() */
+ unsigned long update_time; /* jiffies when data read */
+ char raw[DS2760_DATA_SIZE]; /* raw DS2760 data */
+ int voltage_raw; /* units of 4.88 mV */
+ int voltage_mV; /* units of mV */
+ int current_raw; /* units of 0.625 mA */
+ int current_mA; /* units of mA */
+ int accum_current_raw; /* units of 0.25 mAh */
+ int accum_current_mAh; /* units of mAh */
+ int temp_raw; /* units of 0.125 C */
+ int temp_C; /* units of 0.1 C */
+ int rated_capacity; /* units of mAh */
+ int rem_capacity; /* percentage */
+ int full_active_mAh; /* units of mAh */
+ int empty_mAh; /* units of mAh */
+ int life_min; /* units of minutes */
+ int charge_status; /* BATTERY_STATUS_* */
+
+ int full_counter;
+ struct battery batt;
+ struct device *w1_dev;
+ struct workqueue_struct *monitor_wqueue;
+ struct delayed_work monitor_work;
+};
+
+static unsigned int cache_time = 1000;
+module_param(cache_time, uint, 0644);
+MODULE_PARM_DESC(cache_time, "cache time in milliseconds");
+
+/* Some batteries have their rated capacity stored a N * 10 mAh, while
+ * others use an index into this table. */
+static int rated_capacities[] = {
+ 0,
+ 920, /* Samsung */
+ 920, /* BYD */
+ 920, /* Lishen */
+ 920, /* NEC */
+ 1440, /* Samsung */
+ 1440, /* BYD */
+ 1440, /* Lishen */
+ 1440, /* NEC */
+ 2880, /* Samsung */
+ 2880, /* BYD */
+ 2880, /* Lishen */
+ 2880 /* NEC */
+};
+
+/* array is level at temps 0C, 10C, 20C, 30C, 40C
+ * temp is in Celsius */
+static int battery_interpolate(int array[], int temp)
+{
+ int index, dt;
+
+ if (temp <= 0)
+ return array[0];
+ if (temp >= 40)
+ return array[4];
+
+ index = temp / 10;
+ dt = temp % 10;
+
+ return array[index] + (((array[index + 1] - array[index]) * dt) / 10);
+}
+
+static int ds2760_battery_read_status(struct ds2760_device_info *di)
+{
+ int ret, i, start, count, scale[5];
+
+ if (di->update_time && time_before(jiffies, di->update_time +
+ msecs_to_jiffies(cache_time)))
+ return 0;
+
+ if (!di->w1_dev)
+ return 0;
+
+ /* The first time we read the entire contents of SRAM/EEPROM,
+ * but after that we just read the interesting bits that change. */
+ if (di->update_time == 0) {
+ start = 0;
+ count = DS2760_DATA_SIZE;
+ }
+ else {
+ start = DS2760_VOLTAGE_MSB;
+ count = DS2760_TEMP_LSB - start + 1;
+ }
+
+ ret = w1_ds2760_read(di->w1_dev, di->raw + start, start, count);
+ if (ret != count) {
+ printk("call to w1_ds2760_read failed (0x%08x)\n",
+ (unsigned int)di->w1_dev);
+ return 1;
+ }
+
+ di->update_time = jiffies;
+
+ /* DS2760 reports voltage in units of 4.88mV, but the battery class
+ * reports in units of mV, so convert by multiplying by 4.875.
+ * We approximate because integer math is cheap, and close enough. */
+ di->voltage_raw = (di->raw[DS2760_VOLTAGE_MSB] << 3) |
+ (di->raw[DS2760_VOLTAGE_LSB] >> 5);
+ di->voltage_mV = (di->voltage_raw * 5) - (di->voltage_raw / 8);
+
+ /* DS2760 reports current in signed units of 0.625mA, but the battery
+ * class reports in units of mA, so convert by multiplying by 0.625. */
+ di->current_raw =
+ (((signed char)di->raw[DS2760_CURRENT_MSB]) << 5) |
+ (di->raw[DS2760_CURRENT_LSB] >> 3);
+ di->current_mA = (di->current_raw / 2) + (di->current_raw / 8);
+
+ /* DS2760 reports accumulated current in signed units of 0.25mAh. */
+ di->accum_current_raw =
+ (((signed char)di->raw[DS2760_CURRENT_ACCUM_MSB]) << 8) |
+ di->raw[DS2760_CURRENT_ACCUM_LSB];
+ di->accum_current_mAh = di->accum_current_raw / 4;
+
+ /* DS2760 reports temperature in signed units of 0.125C, but the
+ * battery class reports in units of 1/10 C, so we convert by
+ * multiplying by .125 * 10 = 1.25. */
+ di->temp_raw = (((signed char)di->raw[DS2760_TEMP_MSB]) << 3) |
+ (di->raw[DS2760_TEMP_LSB] >> 5);
+ di->temp_C = di->temp_raw + (di->temp_raw / 4);
+
+ /* At least some battery monitors (e.g. HP iPAQ) store the battery's
+ * maximum rated capacity. */
+ if (di->raw[DS2760_RATED_CAPACITY] < ARRAY_SIZE(rated_capacities))
+ di->rated_capacity = rated_capacities[
+ (unsigned int)di->raw[DS2760_RATED_CAPACITY]];
+ else
+ di->rated_capacity = di->raw[DS2760_RATED_CAPACITY] * 10;
+
+ /* Calculate the full level at the present temperature. */
+ di->full_active_mAh = di->raw[DS2760_ACTIVE_FULL] << 8 |
+ di->raw[DS2760_ACTIVE_FULL + 1];
+
+ scale[0] = di->raw[DS2760_ACTIVE_FULL] << 8 |
+ di->raw[DS2760_ACTIVE_FULL + 1];
+ for (i = 1; i < 5; i++)
+ scale[i] = scale[i - 1] + di->raw[DS2760_ACTIVE_FULL + 2 + i];
+
+ di->full_active_mAh = battery_interpolate(scale, di->temp_C / 10);
+
+ /* Calculate the empty level at the present temperature. */
+ scale[4] = di->raw[DS2760_ACTIVE_EMPTY + 4];
+ for (i = 3; i >= 0; i--)
+ scale[i] = scale[i + 1] + di->raw[DS2760_ACTIVE_EMPTY + i];
+
+ di->empty_mAh = battery_interpolate(scale, di->temp_C / 10);
+
+ /* From Maxim Application Note 131: remaining capacity =
+ * ((ICA - Empty Value) / (Full Value - Empty Value)) x 100% */
+ di->rem_capacity = ((di->accum_current_mAh - di->empty_mAh) * 100) /
+ (di->full_active_mAh - di->empty_mAh);
+
+ if (di->rem_capacity < 0)
+ di->rem_capacity = 0;
+ if (di->rem_capacity > 100)
+ di->rem_capacity = 100;
+
+ if (di->current_mA)
+ di->life_min = -((di->accum_current_mAh - di->empty_mAh) *
+ 60) / di->current_mA;
+ else
+ di->life_min = 0;
+
+ return 0;
+}
+
+static void ds2760_battery_update_status(struct ds2760_device_info *di)
+{
+ int old_charge_status = di->charge_status;
+
+ ds2760_battery_read_status(di);
+
+ if (di->charge_status == BATTERY_STATUS_UNKNOWN)
+ di->full_counter = 0;
+
+ if (battery_is_external_power_supplied(&di->batt)) {
+ if (di->current_mA > 10) {
+ di->charge_status = BATTERY_STATUS_CHARGING;
+ di->full_counter = 0;
+ }
+ else if (di->current_mA < -5) {
+ if (di->charge_status != BATTERY_STATUS_DISCHARGING)
+ printk(KERN_WARNING "%s: not enough power to "
+ "charge\n", di->bi->name);
+ di->charge_status = BATTERY_STATUS_DISCHARGING;
+ di->full_counter = 0;
+ }
+ else if (di->current_mA < 10 &&
+ di->charge_status != BATTERY_STATUS_FULL) {
+
+ /* Don't consider the battery to be full unless
+ * we've seen the current < 10 mA at least two
+ * consecutive times. */
+
+ di->full_counter++;
+
+ if (di->full_counter < 2)
+ di->charge_status = BATTERY_STATUS_CHARGING;
+ else {
+ unsigned char acr[2];
+
+ acr[0] = (di->full_active_mAh * 4) >> 8;
+ acr[1] = (di->full_active_mAh * 4) & 0xff;
+
+ if (w1_ds2760_write(di->w1_dev, acr,
+ DS2760_CURRENT_ACCUM_MSB, 2) < 2)
+ printk(KERN_ERR "ACR reset failed\n");
+ di->charge_status = BATTERY_STATUS_FULL;
+ }
+ }
+ }
+ else {
+ di->charge_status = BATTERY_STATUS_DISCHARGING;
+ di->full_counter = 0;
+ }
+
+ if (di->charge_status != old_charge_status)
+ battery_status_changed(&di->batt);
+
+ return;
+}
+
+static int ds2760_battery_match_callback(struct device *dev, void *data)
+{
+ struct w1_slave *sl;
+
+ if (!(dev->driver && dev->driver->name &&
+ (strcmp(dev->driver->name, "w1_slave_driver") == 0)))
+ return 0;
+
+ sl = container_of(dev, struct w1_slave, dev);
+
+ /* DS2760 w1 slave device names begin with the family number 0x30. */
+ if (strncmp(sl->name, "30-", 3) != 0)
+ return 0;
+
+ return 1;
+}
+
+static void ds2760_battery_work(struct work_struct *work)
+{
+ struct ds2760_device_info *di = container_of(work,
+ struct ds2760_device_info, monitor_work.work);
+ struct bus_type *bus;
+ int interval = HZ * 60;
+
+ pr_debug("%s\n", __FUNCTION__);
+
+ if (!di->w1_dev) {
+ /* Get the battery w1 slave device. */
+ bus = find_bus("w1");
+ if (bus)
+ di->w1_dev = bus_find_device(bus, NULL, NULL,
+ ds2760_battery_match_callback);
+
+ if (!di->w1_dev) {
+ pr_debug("%s: no dev found\n", __FUNCTION__);
+ interval = HZ * 10;
+ goto again_please;
+ }
+ pr_debug("%s: dev found\n", __FUNCTION__);
+ }
+
+ ds2760_battery_update_status(di);
+
+again_please:
+ queue_delayed_work(di->monitor_wqueue, &di->monitor_work, interval);
+ return;
+}
+
+#define to_ds2760_device_info(x) container_of((x), struct ds2760_device_info, \
+ batt);
+
+static void ds2760_battery_external_power_changed(struct battery *bat)
+{
+ struct ds2760_device_info *di = to_ds2760_device_info(bat);
+
+ pr_debug("%s\n", __FUNCTION__);
+
+ cancel_delayed_work(&di->monitor_work);
+ queue_delayed_work(di->monitor_wqueue, &di->monitor_work, HZ/10);
+
+ return;
+}
+
+static void *ds2760_battery_get_property(struct battery *bat,
+ enum battery_property bp)
+{
+ struct ds2760_device_info *di = to_ds2760_device_info(bat);
+
+ switch (bp) {
+ case BATTERY_PROP_MAX_VOLTAGE:
+ return &di->bi->max_voltage;
+ case BATTERY_PROP_MIN_VOLTAGE:
+ return &di->bi->min_voltage;
+ case BATTERY_PROP_VOLTAGE:
+ ds2760_battery_read_status(di);
+ return &di->voltage_mV;
+ case BATTERY_PROP_MAX_CURRENT:
+ return &di->bi->max_current;
+ case BATTERY_PROP_CURRENT:
+ ds2760_battery_read_status(di);
+ return &di->current_mA;
+ case BATTERY_PROP_MAX_CHARGE:
+ ds2760_battery_read_status(di);
+ return &di->full_active_mAh;
+ case BATTERY_PROP_MIN_CHARGE:
+ ds2760_battery_read_status(di);
+ return &di->empty_mAh;
+ case BATTERY_PROP_CHARGE:
+ ds2760_battery_read_status(di);
+ return &di->accum_current_mAh;
+ case BATTERY_PROP_TEMP:
+ ds2760_battery_read_status(di);
+ return &di->temp_C;
+ case BATTERY_PROP_STATUS:
+ return &di->charge_status;
+ default:
+ return NULL;
+ };
+}
+
+static int ds2760_battery_properties[] = {
+ BATTERY_PROP_MAX_VOLTAGE,
+ BATTERY_PROP_MIN_VOLTAGE,
+ BATTERY_PROP_VOLTAGE,
+ BATTERY_PROP_MAX_CURRENT,
+ BATTERY_PROP_CURRENT,
+ BATTERY_PROP_MAX_CHARGE,
+ BATTERY_PROP_MIN_CHARGE,
+ BATTERY_PROP_CHARGE,
+ BATTERY_PROP_TEMP,
+ BATTERY_PROP_STATUS,
+};
+
+static int ds2760_battery_probe(struct platform_device *pdev)
+{
+ int retval = 0;
+ struct ds2760_device_info *di;
+ struct ds2760_platform_data *pdata;
+
+ di = kzalloc(sizeof(*di), GFP_KERNEL);
+ if (!di) {
+ retval = -ENOMEM;
+ goto di_alloc_failed;
+ }
+
+ platform_set_drvdata(pdev, di);
+
+ pdata = pdev->dev.platform_data;
+ di->bi = &pdata->battery_info;
+
+ di->batt.name = di->bi->name;
+ di->batt.properties = ds2760_battery_properties;
+ di->batt.num_properties = ARRAY_SIZE(ds2760_battery_properties);
+ di->batt.get_property = ds2760_battery_get_property;
+ di->batt.external_power_changed =
+ ds2760_battery_external_power_changed;
+
+ di->charge_status = BATTERY_STATUS_UNKNOWN;
+
+ retval = battery_register(&pdev->dev, &di->batt);
+ if (retval) {
+ printk(KERN_ERR "Failed to register class dev for %s",
+ pdev->name);
+ goto batt_failed;
+ }
+
+ INIT_DELAYED_WORK(&di->monitor_work, ds2760_battery_work);
+ di->monitor_wqueue = create_singlethread_workqueue("ds2760_mon");
+ if (!di->monitor_wqueue) {
+ retval = -ESRCH;
+ goto workqueue_failed;
+ }
+ queue_delayed_work(di->monitor_wqueue, &di->monitor_work, HZ * 1);
+
+ goto success;
+
+workqueue_failed:
+ battery_unregister(&di->batt);
+batt_failed:
+ kfree(di);
+di_alloc_failed:
+success:
+ return retval;
+}
+
+static int ds2760_battery_remove(struct platform_device *pdev)
+{
+ struct ds2760_device_info *di = platform_get_drvdata(pdev);
+
+ cancel_rearming_delayed_workqueue(di->monitor_wqueue,
+ &di->monitor_work);
+ destroy_workqueue(di->monitor_wqueue);
+ battery_unregister(&di->batt);
+ if (di->w1_dev)
+ put_device(di->w1_dev);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int ds2760_battery_suspend(struct platform_device *pdev,
+ pm_message_t state)
+{
+ struct ds2760_device_info *di = platform_get_drvdata(pdev);
+
+ di->charge_status = BATTERY_STATUS_UNKNOWN;
+ battery_status_changed(&di->batt);
+
+ return 0;
+}
+
+static int ds2760_battery_resume(struct platform_device *pdev)
+{
+ struct ds2760_device_info *di = platform_get_drvdata(pdev);
+
+ di->charge_status = BATTERY_STATUS_UNKNOWN;
+ battery_status_changed(&di->batt);
+
+ cancel_delayed_work(&di->monitor_work);
+ queue_delayed_work(di->monitor_wqueue, &di->monitor_work, HZ);
+
+ return 0;
+}
+#endif /* CONFIG_PM */
+
+static struct platform_driver ds2760_battery_driver = {
+ .driver = {
+ .name = "ds2760-battery",
+ },
+ .probe = ds2760_battery_probe,
+ .remove = ds2760_battery_remove,
+#ifdef CONFIG_PM
+ .suspend = ds2760_battery_suspend,
+ .resume = ds2760_battery_resume,
+#endif
+};
+
+static int __init ds2760_battery_init(void)
+{
+ return platform_driver_register(&ds2760_battery_driver);
+}
+
+static void __exit ds2760_battery_exit(void)
+{
+ platform_driver_unregister(&ds2760_battery_driver);
+}
+
+module_init(ds2760_battery_init);
+module_exit(ds2760_battery_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Szabolcs Gyurko <szabolcs.gyurko@tlt.hu>, "
+ "Matt Reimer <mreimer@vpop.net>, "
+ "Anton Vorontsov <cbou@mail.ru>");
+MODULE_DESCRIPTION("ds2760 battery driver");
diff --git a/include/linux/ds2760_battery.h b/include/linux/ds2760_battery.h
new file mode 100644
index 0000000..2937a54
--- /dev/null
+++ b/include/linux/ds2760_battery.h
@@ -0,0 +1,32 @@
+/*
+ * Driver for batteries with DS2760 chips inside.
+ *
+ * Copyright (c) 2007 Anton Vorontsov
+ * 2004 Matt Reimer
+ * 2004 Szabolcs Gyurko
+ *
+ * Use consistent with the GNU GPL is permitted,
+ * provided that this copyright notice is
+ * preserved in its entirety in all copies and derived works.
+ *
+ * Author: Anton Vorontsov <cbou@mail.ru>
+ * February 2007
+ *
+ * Matt Reimer <mreimer@vpop.net>
+ * April 2004, 2005
+ *
+ * Szabolcs Gyurko <szabolcs.gyurko@tlt.hu>
+ * September 2004
+ */
+
+#ifndef __DS2760_BATTERY__
+#define __DS2760_BATTERY__
+
+#include <linux/battery.h>
+
+struct ds2760_platform_data {
+ /* Battery information and characteristics. */
+ struct battery_info battery_info;
+};
+
+#endif
--
1.5.0.5-dirty
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2007-04-13 15:57    [from the cache]
©2003-2011 Jasper Spaans. Advertise on this site