power: supply: Add Spreadtrum SC2731 charger support
authorBaolin Wang <baolin.wang@linaro.org>
Mon, 17 Sep 2018 20:03:31 +0000 (13:03 -0700)
committerSebastian Reichel <sebastian.reichel@collabora.com>
Thu, 20 Sep 2018 00:58:08 +0000 (02:58 +0200)
This patch adds the SC2731 PMIC switch charger support.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
drivers/power/supply/Kconfig
drivers/power/supply/Makefile
drivers/power/supply/sc2731_charger.c [new file with mode: 0644]

index ff6dab0..f27cf07 100644 (file)
@@ -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
index a26b402..767105b 100644 (file)
@@ -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 (file)
index 0000000..525a820
--- /dev/null
@@ -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");