[PATCH 38/40] abx500-chargalg: Add charging current step interface
Lee Jones
lee.jones at linaro.org
Fri Feb 15 07:45:08 EST 2013
To prevent overheating, provide differnt steps of charging current
interface to allow thermal mitigation. This will provide possibility
to reduce gradually the charging current.
Signed-off-by: Lee Jones <lee.jones at linaro.org>
---
drivers/power/abx500_chargalg.c | 231 ++++++++++++++++++++++++++-------------
1 file changed, 155 insertions(+), 76 deletions(-)
diff --git a/drivers/power/abx500_chargalg.c b/drivers/power/abx500_chargalg.c
index 7e4bc01..9863e42 100644
--- a/drivers/power/abx500_chargalg.c
+++ b/drivers/power/abx500_chargalg.c
@@ -47,6 +47,9 @@
/* Plus margin for the low battery threshold */
#define BAT_PLUS_MARGIN (100)
+#define CHARGALG_CURR_STEP_LOW 0
+#define CHARGALG_CURR_STEP_HIGH 100
+
#define to_abx500_chargalg_device_info(x) container_of((x), \
struct abx500_chargalg, chargalg_psy);
@@ -80,6 +83,11 @@ struct abx500_chargalg_suspension_status {
bool usb_suspended;
};
+struct abx500_chargalg_current_step_status {
+ bool curr_step_change;
+ int curr_step;
+};
+
struct abx500_chargalg_battery_data {
int temp;
int volt;
@@ -220,6 +228,7 @@ enum maxim_ret {
* @batt_data: data of the battery
* @susp_status: current charger suspension status
* @bm: Platform specific battery management information
+ * @curr_status: Current step status for over-current protection
* @parent: pointer to the struct abx500
* @chargalg_psy: structure that holds the battery properties exposed by
* the charging algorithm
@@ -245,6 +254,7 @@ struct abx500_chargalg {
struct abx500_chargalg_battery_data batt_data;
struct abx500_chargalg_suspension_status susp_status;
struct ab8500 *parent;
+ struct abx500_chargalg_current_step_status curr_status;
struct abx500_bm_data *bm;
struct power_supply chargalg_psy;
struct ux500_charger *ac_chg;
@@ -268,6 +278,12 @@ static enum power_supply_property abx500_chargalg_props[] = {
POWER_SUPPLY_PROP_HEALTH,
};
+struct abx500_chargalg_sysfs_entry {
+ struct attribute attr;
+ ssize_t (*show)(struct abx500_chargalg *, char *);
+ ssize_t (*store)(struct abx500_chargalg *, const char *, size_t);
+};
+
/**
* abx500_chargalg_safety_timer_expired() - Expiration of the safety timer
* @timer: pointer to the hrtimer structure
@@ -402,6 +418,22 @@ static int abx500_chargalg_check_charger_connection(struct abx500_chargalg *di)
}
/**
+ * abx500_chargalg_check_current_step_status() - Check charging current
+ * step status.
+ * @di: pointer to the abx500_chargalg structure
+ *
+ * This function will check if there is a change in the charging current step
+ * and change charge state accordingly.
+ */
+static void abx500_chargalg_check_current_step_status
+ (struct abx500_chargalg *di)
+{
+ if (di->curr_status.curr_step_change)
+ abx500_chargalg_state_to(di, STATE_NORMAL_INIT);
+ di->curr_status.curr_step_change = false;
+}
+
+/**
* abx500_chargalg_start_safety_timer() - Start charging safety timer
* @di: pointer to the abx500_chargalg structure
*
@@ -1300,6 +1332,7 @@ static void abx500_chargalg_algorithm(struct abx500_chargalg *di)
{
int charger_status;
int ret;
+ int curr_step_lvl;
/* Collect data from all power_supply class devices */
class_for_each_device(power_supply_class, NULL,
@@ -1310,6 +1343,7 @@ static void abx500_chargalg_algorithm(struct abx500_chargalg *di)
abx500_chargalg_check_charger_voltage(di);
charger_status = abx500_chargalg_check_charger_connection(di);
+ abx500_chargalg_check_current_step_status(di);
if (is_ab8500(di->parent)) {
ret = abx500_chargalg_check_charger_enable(di);
@@ -1523,9 +1557,18 @@ static void abx500_chargalg_algorithm(struct abx500_chargalg *di)
}
}
- abx500_chargalg_start_charging(di,
- di->bm->bat_type[di->bm->batt_id].normal_vol_lvl,
- di->bm->bat_type[di->bm->batt_id].normal_cur_lvl);
+ if (di->curr_status.curr_step == CHARGALG_CURR_STEP_LOW)
+ abx500_chargalg_stop_charging(di);
+ else {
+ curr_step_lvl = di->bm->bat_type[
+ di->bm->batt_id].normal_cur_lvl
+ * di->curr_status.curr_step
+ / CHARGALG_CURR_STEP_HIGH;
+ abx500_chargalg_start_charging(di,
+ di->bm->bat_type[di->bm->batt_id]
+ .normal_vol_lvl, curr_step_lvl);
+ }
+
abx500_chargalg_state_to(di, STATE_NORMAL);
abx500_chargalg_start_safety_timer(di);
abx500_chargalg_stop_maintenance_timer(di);
@@ -1767,99 +1810,134 @@ static int abx500_chargalg_get_property(struct power_supply *psy,
/* Exposure to the sysfs interface */
-/**
- * abx500_chargalg_sysfs_show() - sysfs show operations
- * @kobj: pointer to the struct kobject
- * @attr: pointer to the struct attribute
- * @buf: buffer that holds the parameter to send to userspace
- *
- * Returns a buffer to be displayed in user space
- */
-static ssize_t abx500_chargalg_sysfs_show(struct kobject *kobj,
- struct attribute *attr, char *buf)
+static ssize_t abx500_chargalg_curr_step_show(struct abx500_chargalg *di,
+ char *buf)
{
- struct abx500_chargalg *di = container_of(kobj,
- struct abx500_chargalg, chargalg_kobject);
+ return sprintf(buf, "%d\n", di->curr_status.curr_step);
+}
+
+static ssize_t abx500_chargalg_curr_step_store(struct abx500_chargalg *di,
+ const char *buf, size_t length)
+{
+ long int param;
+ int ret;
+
+ ret = kstrtol(buf, 10, ¶m);
+ if (ret < 0)
+ return ret;
+ di->curr_status.curr_step = param;
+ if (di->curr_status.curr_step >= CHARGALG_CURR_STEP_LOW &&
+ di->curr_status.curr_step <= CHARGALG_CURR_STEP_HIGH) {
+ di->curr_status.curr_step_change = true;
+ queue_work(di->chargalg_wq, &di->chargalg_work);
+ } else
+ dev_info(di->dev, "Wrong current step\n"
+ "Enter 0. Disable AC/USB Charging\n"
+ "1--100. Set AC/USB charging current step\n"
+ "100. Enable AC/USB Charging\n");
+
+ return strlen(buf);
+}
+
+
+static ssize_t abx500_chargalg_en_show(struct abx500_chargalg *di,
+ char *buf)
+{
return sprintf(buf, "%d\n",
di->susp_status.ac_suspended &&
di->susp_status.usb_suspended);
}
-/**
- * abx500_chargalg_sysfs_charger() - sysfs store operations
- * @kobj: pointer to the struct kobject
- * @attr: pointer to the struct attribute
- * @buf: buffer that holds the parameter passed from userspace
- * @length: length of the parameter passed
- *
- * Returns length of the buffer(input taken from user space) on success
- * else error code on failure
- * The operation to be performed on passing the parameters from the user space.
- */
-static ssize_t abx500_chargalg_sysfs_charger(struct kobject *kobj,
- struct attribute *attr, const char *buf, size_t length)
+static ssize_t abx500_chargalg_en_store(struct abx500_chargalg *di,
+ const char *buf, size_t length)
{
- struct abx500_chargalg *di = container_of(kobj,
- struct abx500_chargalg, chargalg_kobject);
long int param;
int ac_usb;
int ret;
- char entry = *attr->name;
- switch (entry) {
- case 'c':
- ret = strict_strtol(buf, 10, ¶m);
- if (ret < 0)
- return ret;
-
- ac_usb = param;
- switch (ac_usb) {
- case 0:
- /* Disable charging */
- di->susp_status.ac_suspended = true;
- di->susp_status.usb_suspended = true;
- di->susp_status.suspended_change = true;
- /* Trigger a state change */
- queue_work(di->chargalg_wq,
- &di->chargalg_work);
- break;
- case 1:
- /* Enable AC Charging */
- di->susp_status.ac_suspended = false;
- di->susp_status.suspended_change = true;
- /* Trigger a state change */
- queue_work(di->chargalg_wq,
- &di->chargalg_work);
- break;
- case 2:
- /* Enable USB charging */
- di->susp_status.usb_suspended = false;
- di->susp_status.suspended_change = true;
- /* Trigger a state change */
- queue_work(di->chargalg_wq,
- &di->chargalg_work);
- break;
- default:
- dev_info(di->dev, "Wrong input\n"
- "Enter 0. Disable AC/USB Charging\n"
- "1. Enable AC charging\n"
- "2. Enable USB Charging\n");
- };
+ ret = kstrtol(buf, 10, ¶m);
+ if (ret < 0)
+ return ret;
+
+ ac_usb = param;
+ switch (ac_usb) {
+ case 0:
+ /* Disable charging */
+ di->susp_status.ac_suspended = true;
+ di->susp_status.usb_suspended = true;
+ di->susp_status.suspended_change = true;
+ /* Trigger a state change */
+ queue_work(di->chargalg_wq,
+ &di->chargalg_work);
+ break;
+ case 1:
+ /* Enable AC Charging */
+ di->susp_status.ac_suspended = false;
+ di->susp_status.suspended_change = true;
+ /* Trigger a state change */
+ queue_work(di->chargalg_wq,
+ &di->chargalg_work);
break;
+ case 2:
+ /* Enable USB charging */
+ di->susp_status.usb_suspended = false;
+ di->susp_status.suspended_change = true;
+ /* Trigger a state change */
+ queue_work(di->chargalg_wq,
+ &di->chargalg_work);
+ break;
+ default:
+ dev_info(di->dev, "Wrong input\n"
+ "Enter 0. Disable AC/USB Charging\n"
+ "1. Enable AC charging\n"
+ "2. Enable USB Charging\n");
};
return strlen(buf);
}
-static struct attribute abx500_chargalg_en_charger = \
+static struct abx500_chargalg_sysfs_entry abx500_chargalg_en_charger =
+ __ATTR(chargalg, 0644, abx500_chargalg_en_show,
+ abx500_chargalg_en_store);
+
+static struct abx500_chargalg_sysfs_entry abx500_chargalg_curr_step =
+ __ATTR(chargalg_curr_step, 0644, abx500_chargalg_curr_step_show,
+ abx500_chargalg_curr_step_store);
+
+static ssize_t abx500_chargalg_sysfs_show(struct kobject *kobj,
+ struct attribute *attr, char *buf)
+{
+ struct abx500_chargalg_sysfs_entry *entry = container_of(attr,
+ struct abx500_chargalg_sysfs_entry, attr);
+
+ struct abx500_chargalg *di = container_of(kobj,
+ struct abx500_chargalg, chargalg_kobject);
+
+ if (!entry->show)
+ return -EIO;
+
+ return entry->show(di, buf);
+}
+
+static ssize_t abx500_chargalg_sysfs_charger(struct kobject *kobj,
+ struct attribute *attr, const char *buf, size_t length)
{
- .name = "chargalg",
- .mode = S_IRUGO | S_IWUSR,
-};
+ struct abx500_chargalg_sysfs_entry *entry = container_of(attr,
+ struct abx500_chargalg_sysfs_entry, attr);
+
+ struct abx500_chargalg *di = container_of(kobj,
+ struct abx500_chargalg, chargalg_kobject);
+
+ if (!entry->store)
+ return -EIO;
+
+ return entry->store(di, buf, length);
+}
static struct attribute *abx500_chargalg_chg[] = {
- &abx500_chargalg_en_charger,
- NULL
+ &abx500_chargalg_en_charger.attr,
+ &abx500_chargalg_curr_step.attr,
+ NULL,
};
static const struct sysfs_ops abx500_chargalg_sysfs_ops = {
@@ -2052,6 +2130,7 @@ static int abx500_chargalg_probe(struct platform_device *pdev)
dev_err(di->dev, "failed to create sysfs entry\n");
goto free_psy;
}
+ di->curr_status.curr_step = CHARGALG_CURR_STEP_HIGH;
/* Run the charging algorithm */
queue_delayed_work(di->chargalg_wq, &di->chargalg_periodic_work, 0);
--
1.7.10.4
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