| // SPDX-License-Identifier: GPL-2.0-only | 
 | /* | 
 |  * extcon-axp288.c - X-Power AXP288 PMIC extcon cable detection driver | 
 |  * | 
 |  * Copyright (c) 2017-2018 Hans de Goede <hdegoede@redhat.com> | 
 |  * Copyright (C) 2015 Intel Corporation | 
 |  * Author: Ramakrishna Pallala <ramakrishna.pallala@intel.com> | 
 |  */ | 
 |  | 
 | #include <linux/acpi.h> | 
 | #include <linux/module.h> | 
 | #include <linux/kernel.h> | 
 | #include <linux/io.h> | 
 | #include <linux/slab.h> | 
 | #include <linux/interrupt.h> | 
 | #include <linux/platform_device.h> | 
 | #include <linux/property.h> | 
 | #include <linux/notifier.h> | 
 | #include <linux/extcon-provider.h> | 
 | #include <linux/regmap.h> | 
 | #include <linux/mfd/axp20x.h> | 
 | #include <linux/usb/role.h> | 
 | #include <linux/workqueue.h> | 
 |  | 
 | #include <asm/cpu_device_id.h> | 
 | #include <asm/intel-family.h> | 
 |  | 
 | /* Power source status register */ | 
 | #define PS_STAT_VBUS_TRIGGER		BIT(0) | 
 | #define PS_STAT_BAT_CHRG_DIR		BIT(2) | 
 | #define PS_STAT_VBUS_ABOVE_VHOLD	BIT(3) | 
 | #define PS_STAT_VBUS_VALID		BIT(4) | 
 | #define PS_STAT_VBUS_PRESENT		BIT(5) | 
 |  | 
 | /* BC module global register */ | 
 | #define BC_GLOBAL_RUN			BIT(0) | 
 | #define BC_GLOBAL_DET_STAT		BIT(2) | 
 | #define BC_GLOBAL_DBP_TOUT		BIT(3) | 
 | #define BC_GLOBAL_VLGC_COM_SEL		BIT(4) | 
 | #define BC_GLOBAL_DCD_TOUT_MASK		(BIT(6)|BIT(5)) | 
 | #define BC_GLOBAL_DCD_TOUT_300MS	0 | 
 | #define BC_GLOBAL_DCD_TOUT_100MS	1 | 
 | #define BC_GLOBAL_DCD_TOUT_500MS	2 | 
 | #define BC_GLOBAL_DCD_TOUT_900MS	3 | 
 | #define BC_GLOBAL_DCD_DET_SEL		BIT(7) | 
 |  | 
 | /* BC module vbus control and status register */ | 
 | #define VBUS_CNTL_DPDM_PD_EN		BIT(4) | 
 | #define VBUS_CNTL_DPDM_FD_EN		BIT(5) | 
 | #define VBUS_CNTL_FIRST_PO_STAT		BIT(6) | 
 |  | 
 | /* BC USB status register */ | 
 | #define USB_STAT_BUS_STAT_MASK		(BIT(3)|BIT(2)|BIT(1)|BIT(0)) | 
 | #define USB_STAT_BUS_STAT_SHIFT		0 | 
 | #define USB_STAT_BUS_STAT_ATHD		0 | 
 | #define USB_STAT_BUS_STAT_CONN		1 | 
 | #define USB_STAT_BUS_STAT_SUSP		2 | 
 | #define USB_STAT_BUS_STAT_CONF		3 | 
 | #define USB_STAT_USB_SS_MODE		BIT(4) | 
 | #define USB_STAT_DEAD_BAT_DET		BIT(6) | 
 | #define USB_STAT_DBP_UNCFG		BIT(7) | 
 |  | 
 | /* BC detect status register */ | 
 | #define DET_STAT_MASK			(BIT(7)|BIT(6)|BIT(5)) | 
 | #define DET_STAT_SHIFT			5 | 
 | #define DET_STAT_SDP			1 | 
 | #define DET_STAT_CDP			2 | 
 | #define DET_STAT_DCP			3 | 
 |  | 
 | enum axp288_extcon_reg { | 
 | 	AXP288_PS_STAT_REG		= 0x00, | 
 | 	AXP288_PS_BOOT_REASON_REG	= 0x02, | 
 | 	AXP288_BC_GLOBAL_REG		= 0x2c, | 
 | 	AXP288_BC_VBUS_CNTL_REG		= 0x2d, | 
 | 	AXP288_BC_USB_STAT_REG		= 0x2e, | 
 | 	AXP288_BC_DET_STAT_REG		= 0x2f, | 
 | }; | 
 |  | 
 | enum axp288_extcon_irq { | 
 | 	VBUS_FALLING_IRQ = 0, | 
 | 	VBUS_RISING_IRQ, | 
 | 	MV_CHNG_IRQ, | 
 | 	BC_USB_CHNG_IRQ, | 
 | 	EXTCON_IRQ_END, | 
 | }; | 
 |  | 
 | static const unsigned int axp288_extcon_cables[] = { | 
 | 	EXTCON_CHG_USB_SDP, | 
 | 	EXTCON_CHG_USB_CDP, | 
 | 	EXTCON_CHG_USB_DCP, | 
 | 	EXTCON_USB, | 
 | 	EXTCON_NONE, | 
 | }; | 
 |  | 
 | struct axp288_extcon_info { | 
 | 	struct device *dev; | 
 | 	struct regmap *regmap; | 
 | 	struct regmap_irq_chip_data *regmap_irqc; | 
 | 	struct usb_role_switch *role_sw; | 
 | 	struct work_struct role_work; | 
 | 	int irq[EXTCON_IRQ_END]; | 
 | 	struct extcon_dev *edev; | 
 | 	struct extcon_dev *id_extcon; | 
 | 	struct notifier_block id_nb; | 
 | 	unsigned int previous_cable; | 
 | 	bool vbus_attach; | 
 | }; | 
 |  | 
 | static const struct x86_cpu_id cherry_trail_cpu_ids[] = { | 
 | 	{ X86_VENDOR_INTEL, 6, INTEL_FAM6_ATOM_AIRMONT, X86_FEATURE_ANY }, | 
 | 	{} | 
 | }; | 
 |  | 
 | /* Power up/down reason string array */ | 
 | static const char * const axp288_pwr_up_down_info[] = { | 
 | 	"Last wake caused by user pressing the power button", | 
 | 	"Last wake caused by a charger insertion", | 
 | 	"Last wake caused by a battery insertion", | 
 | 	"Last wake caused by SOC initiated global reset", | 
 | 	"Last wake caused by cold reset", | 
 | 	"Last shutdown caused by PMIC UVLO threshold", | 
 | 	"Last shutdown caused by SOC initiated cold off", | 
 | 	"Last shutdown caused by user pressing the power button", | 
 | }; | 
 |  | 
 | /* | 
 |  * Decode and log the given "reset source indicator" (rsi) | 
 |  * register and then clear it. | 
 |  */ | 
 | static void axp288_extcon_log_rsi(struct axp288_extcon_info *info) | 
 | { | 
 | 	unsigned int val, i, clear_mask = 0; | 
 | 	unsigned long bits; | 
 | 	int ret; | 
 |  | 
 | 	ret = regmap_read(info->regmap, AXP288_PS_BOOT_REASON_REG, &val); | 
 | 	if (ret < 0) { | 
 | 		dev_err(info->dev, "failed to read reset source indicator\n"); | 
 | 		return; | 
 | 	} | 
 |  | 
 | 	bits = val & GENMASK(ARRAY_SIZE(axp288_pwr_up_down_info) - 1, 0); | 
 | 	for_each_set_bit(i, &bits, ARRAY_SIZE(axp288_pwr_up_down_info)) | 
 | 		dev_dbg(info->dev, "%s\n", axp288_pwr_up_down_info[i]); | 
 | 	clear_mask = bits; | 
 |  | 
 | 	/* Clear the register value for next reboot (write 1 to clear bit) */ | 
 | 	regmap_write(info->regmap, AXP288_PS_BOOT_REASON_REG, clear_mask); | 
 | } | 
 |  | 
 | /* | 
 |  * The below code to control the USB role-switch on devices with an AXP288 | 
 |  * may seem out of place, but there are 2 reasons why this is the best place | 
 |  * to control the USB role-switch on such devices: | 
 |  * 1) On many devices the USB role is controlled by AML code, but the AML code | 
 |  *    only switches between the host and none roles, because of Windows not | 
 |  *    really using device mode. To make device mode work we need to toggle | 
 |  *    between the none/device roles based on Vbus presence, and this driver | 
 |  *    gets interrupts on Vbus insertion / removal. | 
 |  * 2) In order for our BC1.2 charger detection to work properly the role | 
 |  *    mux must be properly set to device mode before we do the detection. | 
 |  */ | 
 |  | 
 | /* Returns the id-pin value, note pulled low / false == host-mode */ | 
 | static bool axp288_get_id_pin(struct axp288_extcon_info *info) | 
 | { | 
 | 	enum usb_role role; | 
 |  | 
 | 	if (info->id_extcon) | 
 | 		return extcon_get_state(info->id_extcon, EXTCON_USB_HOST) <= 0; | 
 |  | 
 | 	/* We cannot access the id-pin, see what mode the AML code has set */ | 
 | 	role = usb_role_switch_get_role(info->role_sw); | 
 | 	return role != USB_ROLE_HOST; | 
 | } | 
 |  | 
 | static void axp288_usb_role_work(struct work_struct *work) | 
 | { | 
 | 	struct axp288_extcon_info *info = | 
 | 		container_of(work, struct axp288_extcon_info, role_work); | 
 | 	enum usb_role role; | 
 | 	bool id_pin; | 
 | 	int ret; | 
 |  | 
 | 	id_pin = axp288_get_id_pin(info); | 
 | 	if (!id_pin) | 
 | 		role = USB_ROLE_HOST; | 
 | 	else if (info->vbus_attach) | 
 | 		role = USB_ROLE_DEVICE; | 
 | 	else | 
 | 		role = USB_ROLE_NONE; | 
 |  | 
 | 	ret = usb_role_switch_set_role(info->role_sw, role); | 
 | 	if (ret) | 
 | 		dev_err(info->dev, "failed to set role: %d\n", ret); | 
 | } | 
 |  | 
 | static bool axp288_get_vbus_attach(struct axp288_extcon_info *info) | 
 | { | 
 | 	int ret, pwr_stat; | 
 |  | 
 | 	ret = regmap_read(info->regmap, AXP288_PS_STAT_REG, &pwr_stat); | 
 | 	if (ret < 0) { | 
 | 		dev_err(info->dev, "failed to read vbus status\n"); | 
 | 		return false; | 
 | 	} | 
 |  | 
 | 	return !!(pwr_stat & PS_STAT_VBUS_VALID); | 
 | } | 
 |  | 
 | static int axp288_handle_chrg_det_event(struct axp288_extcon_info *info) | 
 | { | 
 | 	int ret, stat, cfg; | 
 | 	u8 chrg_type; | 
 | 	unsigned int cable = info->previous_cable; | 
 | 	bool vbus_attach = false; | 
 |  | 
 | 	vbus_attach = axp288_get_vbus_attach(info); | 
 | 	if (!vbus_attach) | 
 | 		goto no_vbus; | 
 |  | 
 | 	/* Check charger detection completion status */ | 
 | 	ret = regmap_read(info->regmap, AXP288_BC_GLOBAL_REG, &cfg); | 
 | 	if (ret < 0) | 
 | 		goto dev_det_ret; | 
 | 	if (cfg & BC_GLOBAL_DET_STAT) { | 
 | 		dev_dbg(info->dev, "can't complete the charger detection\n"); | 
 | 		goto dev_det_ret; | 
 | 	} | 
 |  | 
 | 	ret = regmap_read(info->regmap, AXP288_BC_DET_STAT_REG, &stat); | 
 | 	if (ret < 0) | 
 | 		goto dev_det_ret; | 
 |  | 
 | 	chrg_type = (stat & DET_STAT_MASK) >> DET_STAT_SHIFT; | 
 |  | 
 | 	switch (chrg_type) { | 
 | 	case DET_STAT_SDP: | 
 | 		dev_dbg(info->dev, "sdp cable is connected\n"); | 
 | 		cable = EXTCON_CHG_USB_SDP; | 
 | 		break; | 
 | 	case DET_STAT_CDP: | 
 | 		dev_dbg(info->dev, "cdp cable is connected\n"); | 
 | 		cable = EXTCON_CHG_USB_CDP; | 
 | 		break; | 
 | 	case DET_STAT_DCP: | 
 | 		dev_dbg(info->dev, "dcp cable is connected\n"); | 
 | 		cable = EXTCON_CHG_USB_DCP; | 
 | 		break; | 
 | 	default: | 
 | 		dev_warn(info->dev, "unknown (reserved) bc detect result\n"); | 
 | 		cable = EXTCON_CHG_USB_SDP; | 
 | 	} | 
 |  | 
 | no_vbus: | 
 | 	extcon_set_state_sync(info->edev, info->previous_cable, false); | 
 | 	if (info->previous_cable == EXTCON_CHG_USB_SDP) | 
 | 		extcon_set_state_sync(info->edev, EXTCON_USB, false); | 
 |  | 
 | 	if (vbus_attach) { | 
 | 		extcon_set_state_sync(info->edev, cable, vbus_attach); | 
 | 		if (cable == EXTCON_CHG_USB_SDP) | 
 | 			extcon_set_state_sync(info->edev, EXTCON_USB, | 
 | 						vbus_attach); | 
 |  | 
 | 		info->previous_cable = cable; | 
 | 	} | 
 |  | 
 | 	if (info->role_sw && info->vbus_attach != vbus_attach) { | 
 | 		info->vbus_attach = vbus_attach; | 
 | 		/* Setting the role can take a while */ | 
 | 		queue_work(system_long_wq, &info->role_work); | 
 | 	} | 
 |  | 
 | 	return 0; | 
 |  | 
 | dev_det_ret: | 
 | 	if (ret < 0) | 
 | 		dev_err(info->dev, "failed to detect BC Mod\n"); | 
 |  | 
 | 	return ret; | 
 | } | 
 |  | 
 | static int axp288_extcon_id_evt(struct notifier_block *nb, | 
 | 				unsigned long event, void *param) | 
 | { | 
 | 	struct axp288_extcon_info *info = | 
 | 		container_of(nb, struct axp288_extcon_info, id_nb); | 
 |  | 
 | 	/* We may not sleep and setting the role can take a while */ | 
 | 	queue_work(system_long_wq, &info->role_work); | 
 |  | 
 | 	return NOTIFY_OK; | 
 | } | 
 |  | 
 | static irqreturn_t axp288_extcon_isr(int irq, void *data) | 
 | { | 
 | 	struct axp288_extcon_info *info = data; | 
 | 	int ret; | 
 |  | 
 | 	ret = axp288_handle_chrg_det_event(info); | 
 | 	if (ret < 0) | 
 | 		dev_err(info->dev, "failed to handle the interrupt\n"); | 
 |  | 
 | 	return IRQ_HANDLED; | 
 | } | 
 |  | 
 | static void axp288_extcon_enable(struct axp288_extcon_info *info) | 
 | { | 
 | 	regmap_update_bits(info->regmap, AXP288_BC_GLOBAL_REG, | 
 | 						BC_GLOBAL_RUN, 0); | 
 | 	/* Enable the charger detection logic */ | 
 | 	regmap_update_bits(info->regmap, AXP288_BC_GLOBAL_REG, | 
 | 					BC_GLOBAL_RUN, BC_GLOBAL_RUN); | 
 | } | 
 |  | 
 | static void axp288_put_role_sw(void *data) | 
 | { | 
 | 	struct axp288_extcon_info *info = data; | 
 |  | 
 | 	cancel_work_sync(&info->role_work); | 
 | 	usb_role_switch_put(info->role_sw); | 
 | } | 
 |  | 
 | static int axp288_extcon_probe(struct platform_device *pdev) | 
 | { | 
 | 	struct axp288_extcon_info *info; | 
 | 	struct axp20x_dev *axp20x = dev_get_drvdata(pdev->dev.parent); | 
 | 	struct device *dev = &pdev->dev; | 
 | 	struct acpi_device *adev; | 
 | 	int ret, i, pirq; | 
 |  | 
 | 	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL); | 
 | 	if (!info) | 
 | 		return -ENOMEM; | 
 |  | 
 | 	info->dev = &pdev->dev; | 
 | 	info->regmap = axp20x->regmap; | 
 | 	info->regmap_irqc = axp20x->regmap_irqc; | 
 | 	info->previous_cable = EXTCON_NONE; | 
 | 	INIT_WORK(&info->role_work, axp288_usb_role_work); | 
 | 	info->id_nb.notifier_call = axp288_extcon_id_evt; | 
 |  | 
 | 	platform_set_drvdata(pdev, info); | 
 |  | 
 | 	info->role_sw = usb_role_switch_get(dev); | 
 | 	if (IS_ERR(info->role_sw)) | 
 | 		return PTR_ERR(info->role_sw); | 
 | 	if (info->role_sw) { | 
 | 		ret = devm_add_action_or_reset(dev, axp288_put_role_sw, info); | 
 | 		if (ret) | 
 | 			return ret; | 
 |  | 
 | 		adev = acpi_dev_get_first_match_dev("INT3496", NULL, -1); | 
 | 		if (adev) { | 
 | 			info->id_extcon = extcon_get_extcon_dev(acpi_dev_name(adev)); | 
 | 			put_device(&adev->dev); | 
 | 			if (!info->id_extcon) | 
 | 				return -EPROBE_DEFER; | 
 |  | 
 | 			dev_info(dev, "controlling USB role\n"); | 
 | 		} else { | 
 | 			dev_info(dev, "controlling USB role based on Vbus presence\n"); | 
 | 		} | 
 | 	} | 
 |  | 
 | 	info->vbus_attach = axp288_get_vbus_attach(info); | 
 |  | 
 | 	axp288_extcon_log_rsi(info); | 
 |  | 
 | 	/* Initialize extcon device */ | 
 | 	info->edev = devm_extcon_dev_allocate(&pdev->dev, | 
 | 					      axp288_extcon_cables); | 
 | 	if (IS_ERR(info->edev)) { | 
 | 		dev_err(&pdev->dev, "failed to allocate memory for extcon\n"); | 
 | 		return PTR_ERR(info->edev); | 
 | 	} | 
 |  | 
 | 	/* Register extcon device */ | 
 | 	ret = devm_extcon_dev_register(&pdev->dev, info->edev); | 
 | 	if (ret) { | 
 | 		dev_err(&pdev->dev, "failed to register extcon device\n"); | 
 | 		return ret; | 
 | 	} | 
 |  | 
 | 	for (i = 0; i < EXTCON_IRQ_END; i++) { | 
 | 		pirq = platform_get_irq(pdev, i); | 
 | 		if (pirq < 0) | 
 | 			return pirq; | 
 |  | 
 | 		info->irq[i] = regmap_irq_get_virq(info->regmap_irqc, pirq); | 
 | 		if (info->irq[i] < 0) { | 
 | 			dev_err(&pdev->dev, | 
 | 				"failed to get virtual interrupt=%d\n", pirq); | 
 | 			ret = info->irq[i]; | 
 | 			return ret; | 
 | 		} | 
 |  | 
 | 		ret = devm_request_threaded_irq(&pdev->dev, info->irq[i], | 
 | 				NULL, axp288_extcon_isr, | 
 | 				IRQF_ONESHOT | IRQF_NO_SUSPEND, | 
 | 				pdev->name, info); | 
 | 		if (ret) { | 
 | 			dev_err(&pdev->dev, "failed to request interrupt=%d\n", | 
 | 							info->irq[i]); | 
 | 			return ret; | 
 | 		} | 
 | 	} | 
 |  | 
 | 	if (info->id_extcon) { | 
 | 		ret = devm_extcon_register_notifier_all(dev, info->id_extcon, | 
 | 							&info->id_nb); | 
 | 		if (ret) | 
 | 			return ret; | 
 | 	} | 
 |  | 
 | 	/* Make sure the role-sw is set correctly before doing BC detection */ | 
 | 	if (info->role_sw) { | 
 | 		queue_work(system_long_wq, &info->role_work); | 
 | 		flush_work(&info->role_work); | 
 | 	} | 
 |  | 
 | 	/* Start charger cable type detection */ | 
 | 	axp288_extcon_enable(info); | 
 |  | 
 | 	device_init_wakeup(dev, true); | 
 | 	platform_set_drvdata(pdev, info); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int __maybe_unused axp288_extcon_suspend(struct device *dev) | 
 | { | 
 | 	struct axp288_extcon_info *info = dev_get_drvdata(dev); | 
 |  | 
 | 	if (device_may_wakeup(dev)) | 
 | 		enable_irq_wake(info->irq[VBUS_RISING_IRQ]); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static int __maybe_unused axp288_extcon_resume(struct device *dev) | 
 | { | 
 | 	struct axp288_extcon_info *info = dev_get_drvdata(dev); | 
 |  | 
 | 	/* | 
 | 	 * Wakeup when a charger is connected to do charger-type | 
 | 	 * connection and generate an extcon event which makes the | 
 | 	 * axp288 charger driver set the input current limit. | 
 | 	 */ | 
 | 	if (device_may_wakeup(dev)) | 
 | 		disable_irq_wake(info->irq[VBUS_RISING_IRQ]); | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static SIMPLE_DEV_PM_OPS(axp288_extcon_pm_ops, axp288_extcon_suspend, | 
 | 			 axp288_extcon_resume); | 
 |  | 
 | static const struct platform_device_id axp288_extcon_table[] = { | 
 | 	{ .name = "axp288_extcon" }, | 
 | 	{}, | 
 | }; | 
 | MODULE_DEVICE_TABLE(platform, axp288_extcon_table); | 
 |  | 
 | static struct platform_driver axp288_extcon_driver = { | 
 | 	.probe = axp288_extcon_probe, | 
 | 	.id_table = axp288_extcon_table, | 
 | 	.driver = { | 
 | 		.name = "axp288_extcon", | 
 | 		.pm = &axp288_extcon_pm_ops, | 
 | 	}, | 
 | }; | 
 |  | 
 | static struct device_connection axp288_extcon_role_sw_conn = { | 
 | 	.endpoint[0] = "axp288_extcon", | 
 | 	.endpoint[1] = "intel_xhci_usb_sw-role-switch", | 
 | 	.id = "usb-role-switch", | 
 | }; | 
 |  | 
 | static int __init axp288_extcon_init(void) | 
 | { | 
 | 	if (x86_match_cpu(cherry_trail_cpu_ids)) | 
 | 		device_connection_add(&axp288_extcon_role_sw_conn); | 
 |  | 
 | 	return platform_driver_register(&axp288_extcon_driver); | 
 | } | 
 | module_init(axp288_extcon_init); | 
 |  | 
 | static void __exit axp288_extcon_exit(void) | 
 | { | 
 | 	if (x86_match_cpu(cherry_trail_cpu_ids)) | 
 | 		device_connection_remove(&axp288_extcon_role_sw_conn); | 
 |  | 
 | 	platform_driver_unregister(&axp288_extcon_driver); | 
 | } | 
 | module_exit(axp288_extcon_exit); | 
 |  | 
 | MODULE_AUTHOR("Ramakrishna Pallala <ramakrishna.pallala@intel.com>"); | 
 | MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>"); | 
 | MODULE_DESCRIPTION("X-Powers AXP288 extcon driver"); | 
 | MODULE_LICENSE("GPL v2"); |