[PATCH v3 2/2] power: supply: Add Spreadtrum SC2731 charger support

From: Baolin Wang
Date: Mon Sep 17 2018 - 16:04:53 EST


This patch adds the SC2731 PMIC switch charger support.

Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxx>
Reviewed-by: Krzysztof Kozlowski <krzk@xxxxxxxxxx>
---
Changes from v2:
- Add reviewed tag from Krzysztof.
- Change current unit to uA instead of mA.

Changes from v1:
- Remove some redundant head files.
- Add one mutex to make sure getting the charger status is correct.
- Fix some coding style issues.
- Use standard DT properties.
---
drivers/power/supply/Kconfig | 7 +
drivers/power/supply/Makefile | 1 +
drivers/power/supply/sc2731_charger.c | 504 ++++++++++++++++++++++++++++++++++
3 files changed, 512 insertions(+)
create mode 100644 drivers/power/supply/sc2731_charger.c

diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig
index ff6dab0..f27cf07 100644
--- a/drivers/power/supply/Kconfig
+++ b/drivers/power/supply/Kconfig
@@ -645,4 +645,11 @@ config CHARGER_CROS_USBPD
what is connected to USB PD ports from the EC and converts
that into power_supply properties.

+config CHARGER_SC2731
+ tristate "Spreadtrum SC2731 charger driver"
+ depends on MFD_SC27XX_PMIC || COMPILE_TEST
+ help
+ Say Y here to enable support for battery charging with SC2731
+ PMIC chips.
+
endif # POWER_SUPPLY
diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile
index a26b402..767105b 100644
--- a/drivers/power/supply/Makefile
+++ b/drivers/power/supply/Makefile
@@ -85,3 +85,4 @@ obj-$(CONFIG_CHARGER_TPS65217) += tps65217_charger.o
obj-$(CONFIG_AXP288_FUEL_GAUGE) += axp288_fuel_gauge.o
obj-$(CONFIG_AXP288_CHARGER) += axp288_charger.o
obj-$(CONFIG_CHARGER_CROS_USBPD) += cros_usbpd-charger.o
+obj-$(CONFIG_CHARGER_SC2731) += sc2731_charger.o
diff --git a/drivers/power/supply/sc2731_charger.c b/drivers/power/supply/sc2731_charger.c
new file mode 100644
index 0000000..525a820
--- /dev/null
+++ b/drivers/power/supply/sc2731_charger.c
@@ -0,0 +1,504 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Spreadtrum Communications Inc.
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/power_supply.h>
+#include <linux/usb/phy.h>
+#include <linux/regmap.h>
+#include <linux/notifier.h>
+#include <linux/of.h>
+
+/* PMIC global registers definition */
+#define SC2731_CHARGE_STATUS 0xedc
+#define SC2731_CHARGE_FULL BIT(4)
+#define SC2731_MODULE_EN1 0xc0c
+#define SC2731_CHARGE_EN BIT(5)
+
+/* SC2731 switch charger registers definition */
+#define SC2731_CHG_CFG0 0x0
+#define SC2731_CHG_CFG1 0x4
+#define SC2731_CHG_CFG2 0x8
+#define SC2731_CHG_CFG3 0xc
+#define SC2731_CHG_CFG4 0x10
+#define SC2731_CHG_CFG5 0x28
+
+/* SC2731_CHG_CFG0 register definition */
+#define SC2731_PRECHG_RNG_SHIFT 11
+#define SC2731_PRECHG_RNG_MASK GENMASK(12, 11)
+
+#define SC2731_TERMINATION_VOL_MASK GENMASK(2, 1)
+#define SC2731_TERMINATION_VOL_SHIFT 1
+#define SC2731_TERMINATION_VOL_CAL_MASK GENMASK(8, 3)
+#define SC2731_TERMINATION_VOL_CAL_SHIFT 3
+#define SC2731_TERMINATION_CUR_MASK GENMASK(2, 0)
+
+#define SC2731_CC_EN BIT(13)
+#define SC2731_CHARGER_PD BIT(0)
+
+/* SC2731_CHG_CFG1 register definition */
+#define SC2731_CUR_MASK GENMASK(5, 0)
+
+/* SC2731_CHG_CFG5 register definition */
+#define SC2731_CUR_LIMIT_SHIFT 8
+#define SC2731_CUR_LIMIT_MASK GENMASK(9, 8)
+
+/* Default current definition (unit is mA) */
+#define SC2731_CURRENT_LIMIT_100 100
+#define SC2731_CURRENT_LIMIT_500 500
+#define SC2731_CURRENT_LIMIT_900 900
+#define SC2731_CURRENT_LIMIT_2000 2000
+#define SC2731_CURRENT_PRECHG 450
+#define SC2731_CURRENT_STEP 50
+
+struct sc2731_charger_info {
+ struct device *dev;
+ struct regmap *regmap;
+ struct usb_phy *usb_phy;
+ struct notifier_block usb_notify;
+ struct power_supply *psy_usb;
+ struct mutex lock;
+ bool charging;
+ u32 base;
+};
+
+static void sc2731_charger_stop_charge(struct sc2731_charger_info *info)
+{
+ regmap_update_bits(info->regmap, info->base + SC2731_CHG_CFG0,
+ SC2731_CC_EN, 0);
+
+ regmap_update_bits(info->regmap, info->base + SC2731_CHG_CFG0,
+ SC2731_CHARGER_PD, SC2731_CHARGER_PD);
+}
+
+static int sc2731_charger_start_charge(struct sc2731_charger_info *info)
+{
+ int ret;
+
+ /* Enable charger constant current mode */
+ ret = regmap_update_bits(info->regmap, info->base + SC2731_CHG_CFG0,
+ SC2731_CC_EN, SC2731_CC_EN);
+ if (ret)
+ return ret;
+
+ /* Start charging */
+ return regmap_update_bits(info->regmap, info->base + SC2731_CHG_CFG0,
+ SC2731_CHARGER_PD, 0);
+}
+
+static int sc2731_charger_set_current_limit(struct sc2731_charger_info *info,
+ u32 limit)
+{
+ u32 val;
+
+ if (limit <= SC2731_CURRENT_LIMIT_100)
+ val = 0;
+ else if (limit <= SC2731_CURRENT_LIMIT_500)
+ val = 3;
+ else if (limit <= SC2731_CURRENT_LIMIT_900)
+ val = 2;
+ else
+ val = 1;
+
+ return regmap_update_bits(info->regmap, info->base + SC2731_CHG_CFG5,
+ SC2731_CUR_LIMIT_MASK,
+ val << SC2731_CUR_LIMIT_SHIFT);
+}
+
+static int sc2731_charger_set_current(struct sc2731_charger_info *info, u32 cur)
+{
+ u32 val;
+ int ret;
+
+ if (cur > SC2731_CURRENT_LIMIT_2000)
+ cur = SC2731_CURRENT_LIMIT_2000;
+ else if (cur < SC2731_CURRENT_PRECHG)
+ cur = SC2731_CURRENT_PRECHG;
+
+ /* Calculate the step value, each step is 50 mA */
+ val = (cur - SC2731_CURRENT_PRECHG) / SC2731_CURRENT_STEP;
+
+ /* Set pre-charge current as 450 mA */
+ ret = regmap_update_bits(info->regmap, info->base + SC2731_CHG_CFG0,
+ SC2731_PRECHG_RNG_MASK,
+ 0x3 << SC2731_PRECHG_RNG_SHIFT);
+ if (ret)
+ return ret;
+
+ return regmap_update_bits(info->regmap, info->base + SC2731_CHG_CFG1,
+ SC2731_CUR_MASK, val);
+}
+
+static int sc2731_charger_get_status(struct sc2731_charger_info *info)
+{
+ u32 val;
+ int ret;
+
+ ret = regmap_read(info->regmap, SC2731_CHARGE_STATUS, &val);
+ if (ret)
+ return ret;
+
+ if (val & SC2731_CHARGE_FULL)
+ return POWER_SUPPLY_STATUS_FULL;
+
+ return POWER_SUPPLY_STATUS_CHARGING;
+}
+
+static int sc2731_charger_get_current(struct sc2731_charger_info *info,
+ u32 *cur)
+{
+ int ret;
+ u32 val;
+
+ ret = regmap_read(info->regmap, info->base + SC2731_CHG_CFG1, &val);
+ if (ret)
+ return ret;
+
+ val &= SC2731_CUR_MASK;
+ *cur = val * SC2731_CURRENT_STEP + SC2731_CURRENT_PRECHG;
+
+ return 0;
+}
+
+static int sc2731_charger_get_current_limit(struct sc2731_charger_info *info,
+ u32 *cur)
+{
+ int ret;
+ u32 val;
+
+ ret = regmap_read(info->regmap, info->base + SC2731_CHG_CFG5, &val);
+ if (ret)
+ return ret;
+
+ val = (val & SC2731_CUR_LIMIT_MASK) >> SC2731_CUR_LIMIT_SHIFT;
+
+ switch (val) {
+ case 0:
+ *cur = SC2731_CURRENT_LIMIT_100;
+ break;
+
+ case 1:
+ *cur = SC2731_CURRENT_LIMIT_2000;
+ break;
+
+ case 2:
+ *cur = SC2731_CURRENT_LIMIT_900;
+ break;
+
+ case 3:
+ *cur = SC2731_CURRENT_LIMIT_500;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int
+sc2731_charger_usb_set_property(struct power_supply *psy,
+ enum power_supply_property psp,
+ const union power_supply_propval *val)
+{
+ struct sc2731_charger_info *info = power_supply_get_drvdata(psy);
+ int ret;
+
+ mutex_lock(&info->lock);
+
+ if (!info->charging) {
+ mutex_unlock(&info->lock);
+ return -ENODEV;
+ }
+
+ switch (psp) {
+ case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT:
+ ret = sc2731_charger_set_current(info, val->intval / 1000);
+ if (ret < 0)
+ dev_err(info->dev, "set charge current failed\n");
+ break;
+
+ case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT:
+ ret = sc2731_charger_set_current_limit(info,
+ val->intval / 1000);
+ if (ret < 0)
+ dev_err(info->dev, "set input current limit failed\n");
+ break;
+
+ default:
+ ret = -EINVAL;
+ }
+
+ mutex_unlock(&info->lock);
+ return ret;
+}
+
+static int sc2731_charger_usb_get_property(struct power_supply *psy,
+ enum power_supply_property psp,
+ union power_supply_propval *val)
+{
+ struct sc2731_charger_info *info = power_supply_get_drvdata(psy);
+ int ret = 0;
+ u32 cur;
+
+ mutex_lock(&info->lock);
+
+ switch (psp) {
+ case POWER_SUPPLY_PROP_STATUS:
+ if (info->charging)
+ val->intval = sc2731_charger_get_status(info);
+ else
+ val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
+ break;
+
+ case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT:
+ if (!info->charging) {
+ val->intval = 0;
+ } else {
+ ret = sc2731_charger_get_current(info, &cur);
+ if (ret)
+ goto out;
+
+ val->intval = cur * 1000;
+ }
+ break;
+
+ case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT:
+ if (!info->charging) {
+ val->intval = 0;
+ } else {
+ ret = sc2731_charger_get_current_limit(info, &cur);
+ if (ret)
+ goto out;
+
+ val->intval = cur * 1000;
+ }
+ break;
+
+ default:
+ ret = -EINVAL;
+ }
+
+out:
+ mutex_unlock(&info->lock);
+ return ret;
+}
+
+static int sc2731_charger_property_is_writeable(struct power_supply *psy,
+ enum power_supply_property psp)
+{
+ int ret;
+
+ switch (psp) {
+ case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT:
+ case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT:
+ ret = 1;
+ break;
+
+ default:
+ ret = 0;
+ }
+
+ return ret;
+}
+
+static enum power_supply_property sc2731_usb_props[] = {
+ POWER_SUPPLY_PROP_STATUS,
+ POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT,
+ POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT,
+};
+
+static const struct power_supply_desc sc2731_charger_desc = {
+ .name = "sc2731_charger",
+ .type = POWER_SUPPLY_TYPE_USB,
+ .properties = sc2731_usb_props,
+ .num_properties = ARRAY_SIZE(sc2731_usb_props),
+ .get_property = sc2731_charger_usb_get_property,
+ .set_property = sc2731_charger_usb_set_property,
+ .property_is_writeable = sc2731_charger_property_is_writeable,
+};
+
+static int sc2731_charger_usb_change(struct notifier_block *nb,
+ unsigned long limit, void *data)
+{
+ struct sc2731_charger_info *info =
+ container_of(nb, struct sc2731_charger_info, usb_notify);
+ int ret = 0;
+
+ mutex_lock(&info->lock);
+
+ if (limit > 0) {
+ /* set current limitation and start to charge */
+ ret = sc2731_charger_set_current_limit(info, limit);
+ if (ret)
+ goto out;
+
+ ret = sc2731_charger_set_current(info, limit);
+ if (ret)
+ goto out;
+
+ ret = sc2731_charger_start_charge(info);
+ if (ret)
+ goto out;
+
+ info->charging = true;
+ } else {
+ /* Stop charging */
+ info->charging = false;
+ sc2731_charger_stop_charge(info);
+ }
+
+out:
+ mutex_unlock(&info->lock);
+ return ret;
+}
+
+static int sc2731_charger_hw_init(struct sc2731_charger_info *info)
+{
+ struct power_supply_battery_info bat_info = { };
+ u32 term_currrent, term_voltage, cur_val, vol_val;
+ int ret;
+
+ /* Enable charger module */
+ ret = regmap_update_bits(info->regmap, SC2731_MODULE_EN1,
+ SC2731_CHARGE_EN, SC2731_CHARGE_EN);
+ if (ret)
+ return ret;
+
+ ret = power_supply_get_battery_info(info->psy_usb, &bat_info);
+ if (ret) {
+ dev_warn(info->dev, "no battery information is supplied\n");
+
+ /*
+ * If no battery information is supplied, we should set
+ * default charge termination current to 120 mA, and default
+ * charge termination voltage to 4.35V.
+ */
+ cur_val = 0x2;
+ vol_val = 0x1;
+ } else {
+ term_currrent = bat_info.charge_term_current_ua / 1000;
+
+ if (term_currrent <= 90)
+ cur_val = 0;
+ else if (term_currrent >= 265)
+ cur_val = 0x7;
+ else
+ cur_val = ((term_currrent - 90) / 25) + 1;
+
+ term_voltage = bat_info.constant_charge_voltage_max_uv / 1000;
+
+ if (term_voltage > 4500)
+ term_voltage = 4500;
+
+ if (term_voltage > 4200)
+ vol_val = (term_voltage - 4200) / 100;
+ else
+ vol_val = 0;
+ }
+
+ /* Set charge termination current */
+ ret = regmap_update_bits(info->regmap, info->base + SC2731_CHG_CFG2,
+ SC2731_TERMINATION_CUR_MASK, cur_val);
+ if (ret)
+ goto error;
+
+ /* Set charge termination voltage */
+ ret = regmap_update_bits(info->regmap, info->base + SC2731_CHG_CFG0,
+ SC2731_TERMINATION_VOL_MASK |
+ SC2731_TERMINATION_VOL_CAL_MASK,
+ (vol_val << SC2731_TERMINATION_VOL_SHIFT) |
+ (0x6 << SC2731_TERMINATION_VOL_CAL_SHIFT));
+ if (ret)
+ goto error;
+
+ return 0;
+
+error:
+ regmap_update_bits(info->regmap, SC2731_MODULE_EN1, SC2731_CHARGE_EN, 0);
+ return ret;
+}
+
+static int sc2731_charger_probe(struct platform_device *pdev)
+{
+ struct device_node *np = pdev->dev.of_node;
+ struct sc2731_charger_info *info;
+ struct power_supply_config charger_cfg = { };
+ int ret;
+
+ info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
+ if (!info)
+ return -ENOMEM;
+
+ mutex_init(&info->lock);
+ info->dev = &pdev->dev;
+
+ info->regmap = dev_get_regmap(pdev->dev.parent, NULL);
+ if (!info->regmap) {
+ dev_err(&pdev->dev, "failed to get charger regmap\n");
+ return -ENODEV;
+ }
+
+ ret = of_property_read_u32(np, "reg", &info->base);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to get register address\n");
+ return -ENODEV;
+ }
+
+ charger_cfg.drv_data = info;
+ charger_cfg.of_node = np;
+ info->psy_usb = devm_power_supply_register(&pdev->dev,
+ &sc2731_charger_desc,
+ &charger_cfg);
+ if (IS_ERR(info->psy_usb)) {
+ dev_err(&pdev->dev, "failed to register power supply\n");
+ return PTR_ERR(info->psy_usb);
+ }
+
+ ret = sc2731_charger_hw_init(info);
+ if (ret)
+ return ret;
+
+ info->usb_phy = devm_usb_get_phy_by_phandle(&pdev->dev, "phys", 0);
+ if (IS_ERR(info->usb_phy)) {
+ dev_err(&pdev->dev, "failed to find USB phy\n");
+ return PTR_ERR(info->usb_phy);
+ }
+
+ info->usb_notify.notifier_call = sc2731_charger_usb_change;
+ ret = usb_register_notifier(info->usb_phy, &info->usb_notify);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to register notifier: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int sc2731_charger_remove(struct platform_device *pdev)
+{
+ struct sc2731_charger_info *info = platform_get_drvdata(pdev);
+
+ usb_unregister_notifier(info->usb_phy, &info->usb_notify);
+
+ return 0;
+}
+
+static const struct of_device_id sc2731_charger_of_match[] = {
+ { .compatible = "sprd,sc2731-charger", },
+ { }
+};
+
+static struct platform_driver sc2731_charger_driver = {
+ .driver = {
+ .name = "sc2731-charger",
+ .of_match_table = sc2731_charger_of_match,
+ },
+ .probe = sc2731_charger_probe,
+ .remove = sc2731_charger_remove,
+};
+
+module_platform_driver(sc2731_charger_driver);
+
+MODULE_DESCRIPTION("Spreadtrum SC2731 Charger Driver");
+MODULE_LICENSE("GPL v2");
--
1.9.1