From 4d3b4aa58ac9e18029c4d0259630414cffd3ba76 Mon Sep 17 00:00:00 2001 From: Lee Jones Date: Fri, 15 Feb 2013 10:58:58 +0000 Subject: [PATCH] abx500-chargalg: Add charging current step interface 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 --- 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); -- 2.7.4