diff mbox series

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

Message ID e8a3aba289cd2505db4a8891256bf731f32072cd.1535446321.git.baolin.wang@linaro.org (mailing list archive)
State Not Applicable, archived
Headers show
Series [1/2] dt-bindings: power: Add Spreadtrum SC2731 charger documentation | expand

Commit Message

(Exiting) Baolin Wang Aug. 28, 2018, 9:02 a.m. UTC
This patch adds the SC2731 PMIC switch charger support.

Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
---
 drivers/power/supply/Kconfig          |    7 +
 drivers/power/supply/Makefile         |    1 +
 drivers/power/supply/sc2731_charger.c |  451 +++++++++++++++++++++++++++++++++
 3 files changed, 459 insertions(+)
 create mode 100644 drivers/power/supply/sc2731_charger.c

Comments

Krzysztof Kozlowski Aug. 29, 2018, 2:36 p.m. UTC | #1
I'll try one more time... but without HTML from Gmail. Previous mail
bounced from lists.

On Tue, 28 Aug 2018 at 11:04, Baolin Wang <baolin.wang@linaro.org> wrote:
>
> This patch adds the SC2731 PMIC switch charger support.
>
> Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
> ---
>  drivers/power/supply/Kconfig          |    7 +
>  drivers/power/supply/Makefile         |    1 +
>  drivers/power/supply/sc2731_charger.c |  451 +++++++++++++++++++++++++++++++++
>  3 files changed, 459 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..49ae16a
> --- /dev/null
> +++ b/drivers/power/supply/sc2731_charger.c
> @@ -0,0 +1,451 @@
> +// SPDX-License-Identifier: GPL-2.0
> +// Copyright (C) 2018 Spreadtrum Communications Inc.
> +
> +#include <linux/err.h>
> +#include <linux/module.h>
> +#include <linux/platform_device.h>
> +#include <linux/power_supply.h>
> +#include <linux/slab.h>

slab.h includes looks not needed.

> +#include <linux/usb/phy.h>
> +#include <linux/regmap.h>
> +#include <linux/extcon.h>

Looks not used.

> +#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)
> +
> +#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

What units are used for all these currents?

> +
> +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;
> +       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;
> +
> +       /* Calculte the step value, each step is 50 mA */

s/Calculte/Calculate/

> +       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;

One empty line please.

> +       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;
> +
> +       switch (psp) {
> +       case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT:
> +               ret = sc2731_charger_set_current(info, val->intval);
> +               if (ret < 0)
> +                       dev_warn(info->dev, "set charge current failed\n");
> +               break;
> +       case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT:
> +               ret = sc2731_charger_set_current_limit(info, val->intval);
> +               if (ret < 0)
> +                       dev_warn(info->dev, "set input current limit failed\n");
> +               break;
> +       default:
> +               ret = -EINVAL;
> +       }
> +
> +       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);
> +       u32 cur;
> +       int ret;
> +
> +       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;
> +                       break;
> +               }
> +
> +               ret = sc2731_charger_get_current(info, &cur);
> +               if (ret)
> +                       return ret;
> +
> +               val->intval = cur;
> +               break;
> +
> +       case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT:
> +               if (!info->charging) {
> +                       val->intval = 0;
> +                       break;
> +               }
> +
> +               ret = sc2731_charger_get_current_limit(info, &cur);
> +               if (ret)
> +                       return ret;
> +
> +               val->intval = cur;
> +               break;
> +
> +       default:
> +               return -EINVAL;
> +       }
> +
> +       return 0;
> +}
> +
> +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;
> +
> +       /* set current limitation and start to charge */
> +       if (limit > 0) {
> +               ret = sc2731_charger_set_current_limit(info, limit);
> +               if (ret)
> +                       return ret;
> +
> +               ret = sc2731_charger_set_current(info, limit);
> +               if (ret)
> +                       return ret;
> +
> +               ret = sc2731_charger_start_charge(info);
> +               if (ret)
> +                       return ret;
> +
> +               info->charging = true;
> +               return 0;
> +       }
> +
> +       /* Stop charging */
> +       sc2731_charger_stop_charge(info);
> +       info->charging = false;

Here and in other places (get_property) you depend on information from
USB phy. But maybe your device already provides information whether it
is charging or not. It should be more accurate.

> +
> +       return 0;
> +}
> +
> +static int sc2731_charger_hw_init(struct sc2731_charger_info *info)
> +{
> +       int ret;
> +
> +       /* Enable charger module */
> +       ret = regmap_update_bits(info->regmap, SC2731_MODULE_EN1,
> +                                SC2731_CHARGE_EN, SC2731_CHARGE_EN);
> +       if (ret)
> +               return ret;
> +
> +       /* Set default charge termination current to 120 mA */
> +       ret = regmap_update_bits(info->regmap, info->base + SC2731_CHG_CFG2,
> +                                SC2731_TERMINATION_CUR_MASK, 0x2);

Looks like DeviceTree property.

> +       if (ret)
> +               goto error;
> +
> +       /* Set default charge termination voltage to 4.35V */

Looks like DeviceTree property.

Best regards,
Krzysztof
(Exiting) Baolin Wang Aug. 30, 2018, 3:08 a.m. UTC | #2
Hi Krzysztof,

On 29 August 2018 at 22:36, Krzysztof Kozlowski <krzk@kernel.org> wrote:
> I'll try one more time... but without HTML from Gmail. Previous mail
> bounced from lists.
>
> On Tue, 28 Aug 2018 at 11:04, Baolin Wang <baolin.wang@linaro.org> wrote:
>>
>> This patch adds the SC2731 PMIC switch charger support.
>>
>> Signed-off-by: Baolin Wang <baolin.wang@linaro.org>
>> ---
>>  drivers/power/supply/Kconfig          |    7 +
>>  drivers/power/supply/Makefile         |    1 +
>>  drivers/power/supply/sc2731_charger.c |  451 +++++++++++++++++++++++++++++++++
>>  3 files changed, 459 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..49ae16a
>> --- /dev/null
>> +++ b/drivers/power/supply/sc2731_charger.c
>> @@ -0,0 +1,451 @@
>> +// SPDX-License-Identifier: GPL-2.0
>> +// Copyright (C) 2018 Spreadtrum Communications Inc.
>> +
>> +#include <linux/err.h>
>> +#include <linux/module.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/power_supply.h>
>> +#include <linux/slab.h>
>
> slab.h includes looks not needed.

Right. will remove it.

>
>> +#include <linux/usb/phy.h>
>> +#include <linux/regmap.h>
>> +#include <linux/extcon.h>
>
> Looks not used.

Will remove it.

>
>> +#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)
>> +
>> +#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
>
> What units are used for all these currents?

Sorry for confusing, and will add comments to explain these macros or
add one postfix ‘MA’.

>
>> +
>> +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;
>> +       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;
>> +
>> +       /* Calculte the step value, each step is 50 mA */
>
> s/Calculte/Calculate/

Sorry for typos.

>
>> +       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;
>
> One empty line please.

OK.

>
>> +       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;
>> +
>> +       switch (psp) {
>> +       case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT:
>> +               ret = sc2731_charger_set_current(info, val->intval);
>> +               if (ret < 0)
>> +                       dev_warn(info->dev, "set charge current failed\n");
>> +               break;
>> +       case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT:
>> +               ret = sc2731_charger_set_current_limit(info, val->intval);
>> +               if (ret < 0)
>> +                       dev_warn(info->dev, "set input current limit failed\n");
>> +               break;
>> +       default:
>> +               ret = -EINVAL;
>> +       }
>> +
>> +       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);
>> +       u32 cur;
>> +       int ret;
>> +
>> +       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;
>> +                       break;
>> +               }
>> +
>> +               ret = sc2731_charger_get_current(info, &cur);
>> +               if (ret)
>> +                       return ret;
>> +
>> +               val->intval = cur;
>> +               break;
>> +
>> +       case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT:
>> +               if (!info->charging) {
>> +                       val->intval = 0;
>> +                       break;
>> +               }
>> +
>> +               ret = sc2731_charger_get_current_limit(info, &cur);
>> +               if (ret)
>> +                       return ret;
>> +
>> +               val->intval = cur;
>> +               break;
>> +
>> +       default:
>> +               return -EINVAL;
>> +       }
>> +
>> +       return 0;
>> +}
>> +
>> +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;
>> +
>> +       /* set current limitation and start to charge */
>> +       if (limit > 0) {
>> +               ret = sc2731_charger_set_current_limit(info, limit);
>> +               if (ret)
>> +                       return ret;
>> +
>> +               ret = sc2731_charger_set_current(info, limit);
>> +               if (ret)
>> +                       return ret;
>> +
>> +               ret = sc2731_charger_start_charge(info);
>> +               if (ret)
>> +                       return ret;
>> +
>> +               info->charging = true;
>> +               return 0;
>> +       }
>> +
>> +       /* Stop charging */
>> +       sc2731_charger_stop_charge(info);
>> +       info->charging = false;
>
> Here and in other places (get_property) you depend on information from
> USB phy. But maybe your device already provides information whether it
> is charging or not. It should be more accurate.

Make sense. Will think about this issue.

>
>> +
>> +       return 0;
>> +}
>> +
>> +static int sc2731_charger_hw_init(struct sc2731_charger_info *info)
>> +{
>> +       int ret;
>> +
>> +       /* Enable charger module */
>> +       ret = regmap_update_bits(info->regmap, SC2731_MODULE_EN1,
>> +                                SC2731_CHARGE_EN, SC2731_CHARGE_EN);
>> +       if (ret)
>> +               return ret;
>> +
>> +       /* Set default charge termination current to 120 mA */
>> +       ret = regmap_update_bits(info->regmap, info->base + SC2731_CHG_CFG2,
>> +                                SC2731_TERMINATION_CUR_MASK, 0x2);
>
> Looks like DeviceTree property.

OK.

>
>> +       if (ret)
>> +               goto error;
>> +
>> +       /* Set default charge termination voltage to 4.35V */
>
> Looks like DeviceTree property.

OK. Thanks for your comments.
Sebastian Reichel Aug. 30, 2018, 9:27 p.m. UTC | #3
Hi,

On Thu, Aug 30, 2018 at 11:08:59AM +0800, Baolin Wang wrote:
> >> +static int sc2731_charger_hw_init(struct sc2731_charger_info *info)
> >> +{
> >> +       int ret;
> >> +
> >> +       /* Enable charger module */
> >> +       ret = regmap_update_bits(info->regmap, SC2731_MODULE_EN1,
> >> +                                SC2731_CHARGE_EN, SC2731_CHARGE_EN);
> >> +       if (ret)
> >> +               return ret;
> >> +
> >> +       /* Set default charge termination current to 120 mA */
> >> +       ret = regmap_update_bits(info->regmap, info->base + SC2731_CHG_CFG2,
> >> +                                SC2731_TERMINATION_CUR_MASK, 0x2);
> >
> > Looks like DeviceTree property.
> 
> OK.
> 
> >
> >> +       if (ret)
> >> +               goto error;
> >> +
> >> +       /* Set default charge termination voltage to 4.35V */
> >
> > Looks like DeviceTree property.
> 
> OK. Thanks for your comments.

I did not review this in detail, but had quick look at this.
Please make sure to derive battery specific DT values using
this:

Documentation/devicetree/bindings/power/supply/battery.txt

-- Sebastian
(Exiting) Baolin Wang Aug. 31, 2018, 5:59 a.m. UTC | #4
Hi Sebastian,

On 31 August 2018 at 05:27, Sebastian Reichel <sre@kernel.org> wrote:
> Hi,
>
> On Thu, Aug 30, 2018 at 11:08:59AM +0800, Baolin Wang wrote:
>> >> +static int sc2731_charger_hw_init(struct sc2731_charger_info *info)
>> >> +{
>> >> +       int ret;
>> >> +
>> >> +       /* Enable charger module */
>> >> +       ret = regmap_update_bits(info->regmap, SC2731_MODULE_EN1,
>> >> +                                SC2731_CHARGE_EN, SC2731_CHARGE_EN);
>> >> +       if (ret)
>> >> +               return ret;
>> >> +
>> >> +       /* Set default charge termination current to 120 mA */
>> >> +       ret = regmap_update_bits(info->regmap, info->base + SC2731_CHG_CFG2,
>> >> +                                SC2731_TERMINATION_CUR_MASK, 0x2);
>> >
>> > Looks like DeviceTree property.
>>
>> OK.
>>
>> >
>> >> +       if (ret)
>> >> +               goto error;
>> >> +
>> >> +       /* Set default charge termination voltage to 4.35V */
>> >
>> > Looks like DeviceTree property.
>>
>> OK. Thanks for your comments.
>
> I did not review this in detail, but had quick look at this.
> Please make sure to derive battery specific DT values using
> this:
>
> Documentation/devicetree/bindings/power/supply/battery.txt

Sure. Will look at this file. Thanks.
diff mbox series

Patch

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..49ae16a
--- /dev/null
+++ b/drivers/power/supply/sc2731_charger.c
@@ -0,0 +1,451 @@ 
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Spreadtrum Communications Inc.
+
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/power_supply.h>
+#include <linux/slab.h>
+#include <linux/usb/phy.h>
+#include <linux/regmap.h>
+#include <linux/extcon.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)
+
+#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;
+	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;
+
+	/* Calculte 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;
+
+	switch (psp) {
+	case POWER_SUPPLY_PROP_CONSTANT_CHARGE_CURRENT:
+		ret = sc2731_charger_set_current(info, val->intval);
+		if (ret < 0)
+			dev_warn(info->dev, "set charge current failed\n");
+		break;
+	case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT:
+		ret = sc2731_charger_set_current_limit(info, val->intval);
+		if (ret < 0)
+			dev_warn(info->dev, "set input current limit failed\n");
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+	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);
+	u32 cur;
+	int ret;
+
+	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;
+			break;
+		}
+
+		ret = sc2731_charger_get_current(info, &cur);
+		if (ret)
+			return ret;
+
+		val->intval = cur;
+		break;
+
+	case POWER_SUPPLY_PROP_INPUT_CURRENT_LIMIT:
+		if (!info->charging) {
+			val->intval = 0;
+			break;
+		}
+
+		ret = sc2731_charger_get_current_limit(info, &cur);
+		if (ret)
+			return ret;
+
+		val->intval = cur;
+		break;
+
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+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;
+
+	/* set current limitation and start to charge */
+	if (limit > 0) {
+		ret = sc2731_charger_set_current_limit(info, limit);
+		if (ret)
+			return ret;
+
+		ret = sc2731_charger_set_current(info, limit);
+		if (ret)
+			return ret;
+
+		ret = sc2731_charger_start_charge(info);
+		if (ret)
+			return ret;
+
+		info->charging = true;
+		return 0;
+	}
+
+	/* Stop charging */
+	sc2731_charger_stop_charge(info);
+	info->charging = false;
+
+	return 0;
+}
+
+static int sc2731_charger_hw_init(struct sc2731_charger_info *info)
+{
+	int ret;
+
+	/* Enable charger module */
+	ret = regmap_update_bits(info->regmap, SC2731_MODULE_EN1,
+				 SC2731_CHARGE_EN, SC2731_CHARGE_EN);
+	if (ret)
+		return ret;
+
+	/* Set default charge termination current to 120 mA */
+	ret = regmap_update_bits(info->regmap, info->base + SC2731_CHG_CFG2,
+				 SC2731_TERMINATION_CUR_MASK, 0x2);
+	if (ret)
+		goto error;
+
+	/* Set default charge termination voltage to 4.35V */
+	ret = regmap_update_bits(info->regmap, info->base + SC2731_CHG_CFG0,
+				 SC2731_TERMINATION_VOL_MASK |
+				 SC2731_TERMINATION_VOL_CAL_MASK,
+				 (0x1 << 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;
+
+	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;
+	}
+
+	info->dev = &pdev->dev;
+	ret = sc2731_charger_hw_init(info);
+	if (ret)
+		return ret;
+
+	charger_cfg.drv_data = info;
+	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);
+	}
+
+	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");