[PATCH 3/3] w1: ds2760_battery: add support for sleep mode feature

Daniel Mack
2009-04-28T08:56:19Z

This adds support for ds2760's sleep mode feature. With this feature
enabled, the chip enters a deep sleep mode and disconnects from the
battery when the w1 line is held down for more than 2 seconds.

This new behaviour can be switched on and off using a new module
parameter.

Cc: Szabolcs Gyurko <szabolcs.gyurko@tlt.hu>
Cc: Matt Reimer <mreimer@vpop.net>
Cc: Anton Vorontsov <cbou@mail.ru>
Signed-off-by: Daniel Mack <daniel@caiaq.de>
---
drivers/power/ds2760_battery.c | 26 ++++++++++++++++++++++++++
drivers/w1/slaves/w1_ds2760.h | 5 +++++
2 files changed, 31 insertions(+), 0 deletions(-)

diff --git a/drivers/power/ds2760_battery.c b/drivers/power/ds2760_battery.c
index 9331009..520b5c4 100644
--- a/drivers/power/ds2760_battery.c
+++ b/drivers/power/ds2760_battery.c
@@ -62,6 +62,10 @@ static unsigned int cache_time = 1000;
module_param(cache_time, uint, 0644);
MODULE_PARM_DESC(cache_time, "cache time in milliseconds");

+static unsigned int pmod_enabled;
+module_param(pmod_enabled, bool, 0644);
+MODULE_PARM_DESC(pmod_enabled, "PMOD enable bit");
+
/* Some batteries have their rated capacity stored a N * 10 mAh, while
* others use an index into this table. */
static int rated_capacities[] = {
@@ -259,6 +263,17 @@ static void ds2760_battery_update_status(struct ds2760_device_info *di)
power_supply_changed(&di->bat);
}

+static void ds2760_battery_write_status(struct ds2760_device_info *di,
+ char status)
+{
+ if (status == di->raw[DS2760_STATUS_REG])
+ return;
+
+ w1_ds2760_write(di->w1_dev, &status, DS2760_STATUS_WRITE_REG, 1);
+ w1_ds2760_store_eeprom(di->w1_dev, DS2760_EEPROM_BLOCK1);
+ w1_ds2760_recall_eeprom(di->w1_dev, DS2760_EEPROM_BLOCK1);
+}
+
static void ds2760_battery_work(struct work_struct *work)
{
struct ds2760_device_info *di = container_of(work,
@@ -342,6 +357,7 @@ static enum power_supply_property ds2760_battery_props[] = {

static int ds2760_battery_probe(struct platform_device *pdev)
{
+ char status;
int retval = 0;
struct ds2760_device_info *di;

@@ -371,6 +387,16 @@ static int ds2760_battery_probe(struct platform_device *pdev)
goto batt_failed;
}

+ /* enable sleep mode feature */
+ ds2760_battery_read_status(di);
+ status = di->raw[DS2760_STATUS_REG];
+ if (pmod_enabled)
+ status |= DS2760_STATUS_PMOD;
+ else
+ status &= ~DS2760_STATUS_PMOD;
+
+ ds2760_battery_write_status(di, status);
+
INIT_DELAYED_WORK(&di->monitor_work, ds2760_battery_work);
di->monitor_wqueue = create_singlethread_workqueue(dev_name(&pdev->dev));
if (!di->monitor_wqueue) {
diff --git a/drivers/w1/slaves/w1_ds2760.h b/drivers/w1/slaves/w1_ds2760.h
index ea39419..58e7741 100644
--- a/drivers/w1/slaves/w1_ds2760.h
+++ b/drivers/w1/slaves/w1_ds2760.h
@@ -25,6 +25,10 @@

#define DS2760_PROTECTION_REG 0x00
#define DS2760_STATUS_REG 0x01
+ #define DS2760_STATUS_IE (1 << 2)
+ #define DS2760_STATUS_SWEN (1 << 3)
+ #define DS2760_STATUS_RNAOP (1 << 4)
+ #define DS2760_STATUS_PMOD (1 << 5)
#define DS2760_EEPROM_REG 0x07
#define DS2760_SPECIAL_FEATURE_REG 0x08
#define DS2760_VOLTAGE_MSB 0x0c
@@ -38,6 +42,7 @@
#define DS2760_EEPROM_BLOCK0 0x20
#define DS2760_ACTIVE_FULL 0x20
#define DS2760_EEPROM_BLOCK1 0x30
+#define DS2760_STATUS_WRITE_REG 0x31
#define DS2760_RATED_CAPACITY 0x32
#define DS2760_CURRENT_OFFSET_BIAS 0x33
#define DS2760_ACTIVE_EMPTY 0x3b
--
1.6.2.1