power: supply: ab8500_chargalg: Drop charging step

There is a sysfs ABI to change the "charging step" of the
charger i.e. limit how much we charge from userspace.

Since we don't have any userspace for this code, this sits
unused and it is not used on production products either.

Drop this code.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>

drivers/power/supply/ab8500_chargalg.c

@@ -46,9 +46,6 @@
 /* Five minutes expressed in seconds */
 #define FIVE_MINUTES_IN_SECONDS        300
 
-#define CHARGALG_CURR_STEP_LOW_UA	0
-#define CHARGALG_CURR_STEP_HIGH_UA	100000
-
 /*
  * This is the battery capacity limit that will trigger a new
  * full charging cycle in the case where maintenance charging
@@ -86,11 +83,6 @@ struct ab8500_chargalg_suspension_status {
 	bool usb_suspended;
 };
 
-struct ab8500_chargalg_current_step_status {
-	bool curr_step_change;
-	int curr_step_ua;
-};
-
 struct ab8500_chargalg_battery_data {
 	int temp;
 	int volt_uv;
@@ -186,8 +178,6 @@ struct ab8500_chargalg_events {
  * struct ab8500_charge_curr_maximization - Charger maximization parameters
  * @original_iset_ua:	the non optimized/maximised charger current
  * @current_iset_ua:	the charging current used at this moment
- * @test_delta_i_ua:	the delta between the current we want to charge and the
-			current that is really going into the battery
  * @condition_cnt:	number of iterations needed before a new charger current
 			is set
  * @max_current_ua:	maximum charger current
@@ -200,7 +190,6 @@ struct ab8500_chargalg_events {
 struct ab8500_charge_curr_maximization {
 	int original_iset_ua;
 	int current_iset_ua;
-	int test_delta_i_ua;
 	int condition_cnt;
 	int max_current_ua;
 	int wait_cnt;
@@ -229,7 +218,6 @@ 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 ab8500
  * @chargalg_psy:	structure that holds the battery properties exposed by
  *			the charging algorithm
@@ -255,7 +243,6 @@ struct ab8500_chargalg {
 	struct ab8500_chargalg_battery_data batt_data;
 	struct ab8500_chargalg_suspension_status susp_status;
 	struct ab8500 *parent;
-	struct ab8500_chargalg_current_step_status curr_status;
 	struct ab8500_bm_data *bm;
 	struct power_supply *chargalg_psy;
 	struct ux500_charger *ac_chg;
@@ -420,22 +407,6 @@ static int ab8500_chargalg_check_charger_connection(struct ab8500_chargalg *di)
 	return di->chg_info.conn_chg;
 }
 
-/**
- * ab8500_chargalg_check_current_step_status() - Check charging current
- * step status.
- * @di:		pointer to the ab8500_chargalg structure
- *
- * This function will check if there is a change in the charging current step
- * and change charge state accordingly.
- */
-static void ab8500_chargalg_check_current_step_status
-	(struct ab8500_chargalg *di)
-{
-	if (di->curr_status.curr_step_change)
-		ab8500_chargalg_state_to(di, STATE_NORMAL_INIT);
-	di->curr_status.curr_step_change = false;
-}
-
 /**
  * ab8500_chargalg_start_safety_timer() - Start charging safety timer
  * @di:		pointer to the ab8500_chargalg structure
@@ -831,7 +802,6 @@ static void init_maxim_chg_curr(struct ab8500_chargalg *di)
 
 	di->ccm.original_iset_ua = bi->constant_charge_current_max_ua;
 	di->ccm.current_iset_ua = bi->constant_charge_current_max_ua;
-	di->ccm.test_delta_i_ua = di->bm->maxi->charger_curr_step_ua;
 	di->ccm.max_current_ua = di->bm->maxi->chg_curr_ua;
 	di->ccm.condition_cnt = di->bm->maxi->wait_cycles;
 	di->ccm.level = 0;
@@ -862,8 +832,7 @@ static enum maxim_ret ab8500_chargalg_chg_curr_maxim(struct ab8500_chargalg *di)
 			dev_dbg(di->dev, "lowering current\n");
 			di->ccm.wait_cnt++;
 			di->ccm.condition_cnt = di->bm->maxi->wait_cycles;
-			di->ccm.max_current_ua =
-				di->ccm.current_iset_ua - di->ccm.test_delta_i_ua;
+			di->ccm.max_current_ua = di->ccm.current_iset_ua;
 			di->ccm.current_iset_ua = di->ccm.max_current_ua;
 			di->ccm.level--;
 			return MAXIM_RET_CHANGE;
@@ -893,29 +862,8 @@ static enum maxim_ret ab8500_chargalg_chg_curr_maxim(struct ab8500_chargalg *di)
 		return MAXIM_RET_IBAT_TOO_HIGH;
 	}
 
-	if (delta_i_ua > di->ccm.test_delta_i_ua &&
-		(di->ccm.current_iset_ua + di->ccm.test_delta_i_ua) <
-		di->ccm.max_current_ua) {
-		if (di->ccm.condition_cnt-- == 0) {
-			/* Increse the iset with cco.test_delta_i */
-			di->ccm.condition_cnt = di->bm->maxi->wait_cycles;
-			di->ccm.current_iset_ua += di->ccm.test_delta_i_ua;
-			di->ccm.level++;
-			dev_dbg(di->dev, " Maximization needed, increase"
-				" with %d uA to %duA (Optimal ibat: %d uA)"
-				" Level %d\n",
-				di->ccm.test_delta_i_ua,
-				di->ccm.current_iset_ua,
-				di->ccm.original_iset_ua,
-				di->ccm.level);
-			return MAXIM_RET_CHANGE;
-		} else {
-			return MAXIM_RET_NOACTION;
-		}
-	}  else {
-		di->ccm.condition_cnt = di->bm->maxi->wait_cycles;
-		return MAXIM_RET_NOACTION;
-	}
+	di->ccm.condition_cnt = di->bm->maxi->wait_cycles;
+	return MAXIM_RET_NOACTION;
 }
 
 static void handle_maxim_chg_curr(struct ab8500_chargalg *di)
@@ -1302,7 +1250,6 @@ static void ab8500_chargalg_algorithm(struct ab8500_chargalg *di)
 	struct power_supply_battery_info *bi = di->bm->bi;
 	int charger_status;
 	int ret;
-	int curr_step_lvl_ua;
 
 	/* Collect data from all power_supply class devices */
 	class_for_each_device(power_supply_class, NULL,
@@ -1313,7 +1260,6 @@ static void ab8500_chargalg_algorithm(struct ab8500_chargalg *di)
 	ab8500_chargalg_check_charger_voltage(di);
 
 	charger_status = ab8500_chargalg_check_charger_connection(di);
-	ab8500_chargalg_check_current_step_status(di);
 
 	if (is_ab8500(di->parent)) {
 		ret = ab8500_chargalg_check_charger_enable(di);
@@ -1511,15 +1457,13 @@ static void ab8500_chargalg_algorithm(struct ab8500_chargalg *di)
 		break;
 
 	case STATE_NORMAL_INIT:
-		if (di->curr_status.curr_step_ua == CHARGALG_CURR_STEP_LOW_UA)
+		if (bi->constant_charge_current_max_ua == 0)
+			/* "charging" with 0 uA */
 			ab8500_chargalg_stop_charging(di);
 		else {
-			curr_step_lvl_ua = bi->constant_charge_current_max_ua
-				* di->curr_status.curr_step_ua
-				/ CHARGALG_CURR_STEP_HIGH_UA;
 			ab8500_chargalg_start_charging(di,
 				bi->constant_charge_voltage_max_uv,
-				curr_step_lvl_ua);
+				bi->constant_charge_current_max_ua);
 		}
 
 		ab8500_chargalg_state_to(di, STATE_NORMAL);
@@ -1742,37 +1686,6 @@ static int ab8500_chargalg_get_property(struct power_supply *psy,
 
 /* Exposure to the sysfs interface */
 
-static ssize_t ab8500_chargalg_curr_step_show(struct ab8500_chargalg *di,
-					      char *buf)
-{
-	return sprintf(buf, "%d\n", di->curr_status.curr_step_ua);
-}
-
-static ssize_t ab8500_chargalg_curr_step_store(struct ab8500_chargalg *di,
-					       const char *buf, size_t length)
-{
-	long param;
-	int ret;
-
-	ret = kstrtol(buf, 10, &param);
-	if (ret < 0)
-		return ret;
-
-	di->curr_status.curr_step_ua = param;
-	if (di->curr_status.curr_step_ua >= CHARGALG_CURR_STEP_LOW_UA &&
-		di->curr_status.curr_step_ua <= CHARGALG_CURR_STEP_HIGH_UA) {
-		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 ab8500_chargalg_en_show(struct ab8500_chargalg *di,
 				       char *buf)
 {
@@ -1832,10 +1745,6 @@ static struct ab8500_chargalg_sysfs_entry ab8500_chargalg_en_charger =
 	__ATTR(chargalg, 0644, ab8500_chargalg_en_show,
 				ab8500_chargalg_en_store);
 
-static struct ab8500_chargalg_sysfs_entry ab8500_chargalg_curr_step =
-	__ATTR(chargalg_curr_step, 0644, ab8500_chargalg_curr_step_show,
-					ab8500_chargalg_curr_step_store);
-
 static ssize_t ab8500_chargalg_sysfs_show(struct kobject *kobj,
 	struct attribute *attr, char *buf)
 {
@@ -1868,7 +1777,6 @@ static ssize_t ab8500_chargalg_sysfs_charger(struct kobject *kobj,
 
 static struct attribute *ab8500_chargalg_chg[] = {
 	&ab8500_chargalg_en_charger.attr,
-	&ab8500_chargalg_curr_step.attr,
 	NULL,
 };
 
@@ -2057,7 +1965,6 @@ static int ab8500_chargalg_probe(struct platform_device *pdev)
 		dev_err(di->dev, "failed to create sysfs entry\n");
 		return ret;
 	}
-	di->curr_status.curr_step_ua = CHARGALG_CURR_STEP_HIGH_UA;
 
 	dev_info(di->dev, "probe success\n");
 	return component_add(dev, &ab8500_chargalg_component_ops);