This simple charger driver uses the USB PHY framework to detect the presence of a charger. Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx> --- drivers/power/supply/Kconfig | 7 ++ drivers/power/supply/Makefile | 1 + drivers/power/supply/generic-usb-charger.c | 140 +++++++++++++++++++++ 3 files changed, 148 insertions(+) create mode 100644 drivers/power/supply/generic-usb-charger.c diff --git a/drivers/power/supply/Kconfig b/drivers/power/supply/Kconfig index c84a7b1caeb6..069a91d89a42 100644 --- a/drivers/power/supply/Kconfig +++ b/drivers/power/supply/Kconfig @@ -51,6 +51,13 @@ config GENERIC_ADC_BATTERY Say Y here to enable support for the generic battery driver which uses IIO framework to read adc. +config GENERIC_USB_CHARGER + tristate "Generic USB charger" + depends on USB_PHY + help + Say Y here to enable a generic USB charger driver which uses + the USB PHY framework to detect the presence of the charger. + config MAX8925_POWER tristate "MAX8925 battery charger support" depends on MFD_MAX8925 diff --git a/drivers/power/supply/Makefile b/drivers/power/supply/Makefile index 6c7da920ea83..03f9b553bdfc 100644 --- a/drivers/power/supply/Makefile +++ b/drivers/power/supply/Makefile @@ -8,6 +8,7 @@ power_supply-$(CONFIG_LEDS_TRIGGERS) += power_supply_leds.o obj-$(CONFIG_POWER_SUPPLY) += power_supply.o obj-$(CONFIG_POWER_SUPPLY_HWMON) += power_supply_hwmon.o obj-$(CONFIG_GENERIC_ADC_BATTERY) += generic-adc-battery.o +obj-$(CONFIG_GENERIC_USB_CHARGER) += generic-usb-charger.o obj-$(CONFIG_PDA_POWER) += pda_power.o obj-$(CONFIG_APM_POWER) += apm_power.o diff --git a/drivers/power/supply/generic-usb-charger.c b/drivers/power/supply/generic-usb-charger.c new file mode 100644 index 000000000000..d005acfc33c7 --- /dev/null +++ b/drivers/power/supply/generic-usb-charger.c @@ -0,0 +1,140 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Simple USB charger driver + * Copyright (c) 2019 Paul Cercueil <paul@xxxxxxxxxxxxxxx> + */ + +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/power_supply.h> +#include <linux/usb/phy.h> + +struct usb_charger { + struct usb_phy *phy; + struct notifier_block nb; + struct power_supply_desc desc; + struct power_supply *charger; +}; + +static enum power_supply_property usb_charger_properties[] = { + POWER_SUPPLY_PROP_ONLINE, +}; + +static int usb_charger_get_property(struct power_supply *psy, + enum power_supply_property psp, + union power_supply_propval *val) +{ + struct usb_charger *charger = power_supply_get_drvdata(psy); + + switch (psp) { + case POWER_SUPPLY_PROP_ONLINE: + val->intval = charger->phy->chg_state == USB_CHARGER_PRESENT; + break; + default: + return -EINVAL; + } + + return 0; +} + +static int usb_charger_event(struct notifier_block *nb, + unsigned long event, void *d) +{ + struct usb_charger *charger = container_of(nb, struct usb_charger, nb); + + power_supply_changed(charger->charger); + + return 0; +} + +static int usb_charger_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct power_supply_desc *desc; + struct usb_charger *charger; + struct power_supply_config cfg = { + .of_node = dev->of_node, + }; + int err; + + charger = devm_kzalloc(dev, sizeof(*charger), GFP_KERNEL); + if (!charger) + return -ENOMEM; + + platform_set_drvdata(pdev, charger); + charger->nb.notifier_call = usb_charger_event; + cfg.drv_data = charger; + + if (dev->of_node) + charger->phy = devm_usb_get_phy_by_phandle(dev, "phys", 0); + else + charger->phy = devm_usb_get_phy(dev, USB_PHY_TYPE_USB2); + if (IS_ERR(charger->phy)) { + err = PTR_ERR(charger->phy); + if (err != -EPROBE_DEFER) + dev_err(dev, "No transceiver configured"); + return err; + } + + desc = &charger->desc; + desc->name = "usb-charger"; + desc->properties = usb_charger_properties; + desc->num_properties = ARRAY_SIZE(usb_charger_properties); + desc->get_property = usb_charger_get_property; + + switch (charger->phy->chg_type) { + case SDP_TYPE: + desc->type = POWER_SUPPLY_TYPE_USB; + break; + case DCP_TYPE: + desc->type = POWER_SUPPLY_TYPE_USB_DCP; + break; + case CDP_TYPE: + desc->type = POWER_SUPPLY_TYPE_USB_CDP; + break; + case ACA_TYPE: + desc->type = POWER_SUPPLY_TYPE_USB_ACA; + break; + default: + desc->type = POWER_SUPPLY_TYPE_UNKNOWN; + } + + charger->charger = devm_power_supply_register(dev, desc, &cfg); + if (IS_ERR(charger->charger)) { + dev_err(dev, "Unable to register charger"); + return PTR_ERR(charger->charger); + } + + return usb_register_notifier(charger->phy, &charger->nb); +} + +static int usb_charger_remove(struct platform_device *pdev) +{ + struct usb_charger *charger = platform_get_drvdata(pdev); + + usb_unregister_notifier(charger->phy, &charger->nb); + + return 0; +} + +#ifdef CONFIG_OF +static const struct of_device_id usb_charger_of_match[] = { + { .compatible = "usb-charger" }, + { /* sentinel */ }, +}; +MODULE_DEVICE_TABLE(of, usb_charger_of_match); +#endif + +static struct platform_driver usb_charger_driver = { + .driver = { + .name = "usb-charger", + .of_match_table = of_match_ptr(usb_charger_of_match), + }, + .probe = usb_charger_probe, + .remove = usb_charger_remove, +}; +module_platform_driver(usb_charger_driver); + +MODULE_DESCRIPTION("Simple USB charger driver"); +MODULE_AUTHOR("Paul Cercueil <paul@xxxxxxxxxxxxxxx>"); +MODULE_LICENSE("GPL"); -- 2.24.0.rc1