Commit c6fdea96 authored by Pavel Machek's avatar Pavel Machek Committed by Sebastian Reichel
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power: supply: cpcap-charger: Limiting charge current on Droid 4 



Droid 4 has same problem as N900: it is often necessary to manually
tweak current draw from USB, for example when using thin charging cable.

Cc: Arthur Demchenkov <spinal.by@gmail.com>
Cc: Carl Philipp Klemm <philipp@uvos.xyz>
Cc: Merlijn Wajer <merlijn@wizzup.org>
Cc: Pavel Machek <pavel@ucw.cz>
Signed-off-by: default avatarPavel Machek <pavel@ucw.cz>
[tony@atomide.com: rebased, cleaned up whitespace issues, updated comments]
Signed-off-by: default avatarTony Lindgren <tony@atomide.com>
Signed-off-by: default avatarSebastian Reichel <sebastian.reichel@collabora.com>
parent 41ac23f5

drivers/power/supply/cpcap-charger.c

+43 −6
Original line number Diff line number Diff line
@@ -89,6 +89,8 @@ 
 * CPCAP_REG_CRM charge currents. These seem to match MC13783UG.pdf

 * values in "Table 8-3. Charge Path Regulator Current Limit

 * Characteristics" for the nominal values.

 *

 * Except 70mA and 1.596A and unlimited, these are simply 88.7mA / step.

 */

#define CPCAP_REG_CRM_ICHRG(val)	(((val) & 0xf) << 0)

#define CPCAP_REG_CRM_ICHRG_0A000	CPCAP_REG_CRM_ICHRG(0x0)
@@ -140,6 +142,7 @@ struct cpcap_charger_ddata { 
	int status;

	int state;

	int voltage;

	int limit_current;

};



struct cpcap_interrupt_desc {
@@ -166,6 +169,7 @@ static enum power_supply_property cpcap_charger_props[] = { 
	POWER_SUPPLY_PROP_STATUS,

	POWER_SUPPLY_PROP_ONLINE,

	POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE,

	POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT,

	POWER_SUPPLY_PROP_VOLTAGE_NOW,

	POWER_SUPPLY_PROP_CURRENT_NOW,

};
@@ -229,6 +233,9 @@ static int cpcap_charger_get_property(struct power_supply *psy, 
	case POWER_SUPPLY_PROP_STATUS:

		val->intval = ddata->status;

		break;

	case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT:

		val->intval = ddata->limit_current;

		break;

	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE:

		val->intval = ddata->voltage;

		break;
@@ -300,6 +307,26 @@ cpcap_charger_get_bat_const_charge_voltage(struct cpcap_charger_ddata *ddata) 
	return voltage;

}



static int cpcap_charger_current_to_regval(int microamp)

{

	int miliamp = microamp / 1000;

	int res;



	if (miliamp < 0)

		return -EINVAL;

	if (miliamp < 70)

		return CPCAP_REG_CRM_ICHRG(0x0);

	if (miliamp < 177)

		return CPCAP_REG_CRM_ICHRG(0x1);

	if (miliamp > 1596)

		return CPCAP_REG_CRM_ICHRG(0xe);



	res = microamp / 88666;

	if (res > 0xd)

		res = 0xd;

	return CPCAP_REG_CRM_ICHRG(res);

}



static int cpcap_charger_set_property(struct power_supply *psy,

				      enum power_supply_property psp,

				      const union power_supply_propval *val)
@@ -308,6 +335,12 @@ static int cpcap_charger_set_property(struct power_supply *psy, 
	int voltage, batvolt;



	switch (psp) {

	case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT:

		if (cpcap_charger_current_to_regval(val->intval) < 0)

			return -EINVAL;

		ddata->limit_current = val->intval;

		schedule_delayed_work(&ddata->detect_work, 0);

		break;

	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE:

		voltage = cpcap_charger_match_voltage(val->intval);

		batvolt = cpcap_charger_get_bat_const_charge_voltage(ddata);
@@ -327,6 +360,7 @@ static int cpcap_charger_property_is_writeable(struct power_supply *psy, 
					       enum power_supply_property psp)

{

	switch (psp) {

	case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT:

	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_VOLTAGE:

		return 1;

	default:
@@ -652,18 +686,20 @@ static void cpcap_usb_detect(struct work_struct *work) 


	if (!ddata->feeding_vbus && cpcap_charger_vbus_valid(ddata) &&

	    s.chrgcurr1) {

		int max_current;

		int vchrg;

		int max_current = 532000;

		int vchrg, ichrg;



		if (cpcap_charger_battery_found(ddata))

			max_current = CPCAP_REG_CRM_ICHRG_1A596;

		else

			max_current = CPCAP_REG_CRM_ICHRG_0A532;

			max_current = 1596000;



		if (max_current > ddata->limit_current)

			max_current = ddata->limit_current;



		ichrg = cpcap_charger_current_to_regval(max_current);

		vchrg = cpcap_charger_voltage_to_regval(ddata->voltage);

		error = cpcap_charger_set_state(ddata,

						CPCAP_REG_CRM_VCHRG(vchrg),

						max_current, 0);

						ichrg, 0);

		if (error)

			goto out_err;

		cpcap_charger_update_state(ddata,
@@ -837,6 +873,7 @@ static int cpcap_charger_probe(struct platform_device *pdev) 


	ddata->dev = &pdev->dev;

	ddata->voltage = 4200000;

	ddata->limit_current = 532000;



	ddata->reg = dev_get_regmap(ddata->dev->parent, NULL);

	if (!ddata->reg)