// SPDX-License-Identifier: GPL-2.0-only/* * Copyright (c) 2015-2021, The Linux Foundation. All rights reserved. */ #include <linux/bitops.h>#include <linux/err.h>#include <linux/interrupt.h>#include <linux/io.h>#include <linux/iopoll.h>#include <linux/kernel.h>#include <linux/module.h>#include <linux/of.h>#include <linux/platform_device.h>#include <linux/slab.h>#include <linux/sysfs.h>#include <linux/usb/role.h>#include <linux/firmware/qcom/qcom_scm.h> #define EUD_REG_INT1_EN_MASK	0x0024#define EUD_REG_INT_STATUS_1	0x0044#define EUD_REG_CTL_OUT_1	0x0074#define EUD_REG_VBUS_INT_CLR	0x0080#define EUD_REG_CSR_EUD_EN	0x1014#define EUD_REG_SW_ATTACH_DET	0x1018#define EUD_REG_EUD_EN2		0x0000 #define EUD_ENABLE		BIT(0)#define EUD_INT_PET_EUD		BIT(0)#define EUD_INT_VBUS		BIT(2)#define EUD_INT_SAFE_MODE	BIT(4)#define EUD_INT_ALL		(EUD_INT_VBUS | EUD_INT_SAFE_MODE) struct eud_chip {	struct device			*dev;	struct usb_role_switch		*role_sw;	void __iomem			*base;	phys_addr_t			mode_mgr;	unsigned int			int_status;	int				irq;	bool				enabled;	bool				usb_attached;}; static int enable_eud(struct eud_chip *priv){	int ret; 	ret = qcom_scm_io_writel(priv->mode_mgr + EUD_REG_EUD_EN2, 1);	if (ret)		return ret; 	writel(EUD_ENABLE, priv->base + EUD_REG_CSR_EUD_EN);	writel(EUD_INT_VBUS | EUD_INT_SAFE_MODE,			priv->base + EUD_REG_INT1_EN_MASK); 	return usb_role_switch_set_role(priv->role_sw, USB_ROLE_DEVICE);} static int disable_eud(struct eud_chip *priv){	int ret; 	ret = qcom_scm_io_writel(priv->mode_mgr + EUD_REG_EUD_EN2, 0);	if (ret)		return ret; 	writel(0, priv->base + EUD_REG_CSR_EUD_EN);	return 0;} static ssize_t enable_show(struct device *dev,		struct device_attribute *attr, char *buf){	struct eud_chip *chip = dev_get_drvdata(dev); 	return sysfs_emit(buf, "%d\n", chip->enabled);} static ssize_t enable_store(struct device *dev,		struct device_attribute *attr,		const char *buf, size_t count){	struct eud_chip *chip = dev_get_drvdata(dev);	bool enable;	int ret; 	if (kstrtobool(buf, &enable))		return -EINVAL; 	if (enable) {		ret = enable_eud(chip);		if (!ret)			chip->enabled = enable;		else			disable_eud(chip); 	} else {		ret = disable_eud(chip);	} 	return ret < 0 ? ret : count;} static DEVICE_ATTR_RW(enable); static struct attribute *eud_attrs[] = {	&dev_attr_enable.attr,	NULL,};ATTRIBUTE_GROUPS(eud); static void usb_attach_detach(struct eud_chip *chip){	u32 reg; 	/* read ctl_out_1[4] to find USB attach or detach event */	reg = readl(chip->base + EUD_REG_CTL_OUT_1);	chip->usb_attached = reg & EUD_INT_SAFE_MODE;} static void pet_eud(struct eud_chip *chip){	u32 reg;	int ret; 	/* When the EUD_INT_PET_EUD in SW_ATTACH_DET is set, the cable has been	 * disconnected and we need to detach the pet to check if EUD is in safe	 * mode before attaching again.	 */	reg = readl(chip->base + EUD_REG_SW_ATTACH_DET);	if (reg & EUD_INT_PET_EUD) {		/* Detach & Attach pet for EUD */		writel(0, chip->base + EUD_REG_SW_ATTACH_DET);		/* Delay to make sure detach pet is done before attach pet */		ret = readl_poll_timeout(chip->base + EUD_REG_SW_ATTACH_DET,					reg, (reg == 0), 1, 100);		if (ret) {			dev_err(chip->dev, "Detach pet failed\n");			return;		}	}	/* Attach pet for EUD */	writel(EUD_INT_PET_EUD, chip->base + EUD_REG_SW_ATTACH_DET);} static irqreturn_t handle_eud_irq(int irq, void *data){	struct eud_chip *chip = data;	u32 reg; 	reg = readl(chip->base + EUD_REG_INT_STATUS_1);	switch (reg & EUD_INT_ALL) {	case EUD_INT_VBUS:		usb_attach_detach(chip);		return IRQ_WAKE_THREAD;	case EUD_INT_SAFE_MODE:		pet_eud(chip);		return IRQ_HANDLED;	default:		return IRQ_NONE;	}} static irqreturn_t handle_eud_irq_thread(int irq, void *data){	struct eud_chip *chip = data;	int ret; 	if (chip->usb_attached)		ret = usb_role_switch_set_role(chip->role_sw, USB_ROLE_DEVICE);	else		ret = usb_role_switch_set_role(chip->role_sw, USB_ROLE_HOST);	if (ret)		dev_err(chip->dev, "failed to set role switch\n"); 	/* set and clear vbus_int_clr[0] to clear interrupt */	writel(BIT(0), chip->base + EUD_REG_VBUS_INT_CLR);	writel(0, chip->base + EUD_REG_VBUS_INT_CLR); 	return IRQ_HANDLED;} static void eud_role_switch_release(void *data){	struct eud_chip *chip = data; 	usb_role_switch_put(chip->role_sw);} static int eud_probe(struct platform_device *pdev){	struct eud_chip *chip;	struct resource *res;	int ret; 	chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);	if (!chip)		return -ENOMEM; 	chip->dev = &pdev->dev; 	chip->role_sw = usb_role_switch_get(&pdev->dev);	if (IS_ERR(chip->role_sw))		return dev_err_probe(chip->dev, PTR_ERR(chip->role_sw),					"failed to get role switch\n"); 	ret = devm_add_action_or_reset(chip->dev, eud_role_switch_release, chip);	if (ret)		return ret; 	chip->base = devm_platform_ioremap_resource(pdev, 0);	if (IS_ERR(chip->base))		return PTR_ERR(chip->base); 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);	if (!res)		return -ENODEV;	chip->mode_mgr = res->start; 	chip->irq = platform_get_irq(pdev, 0);	if (chip->irq < 0)		return chip->irq; 	ret = devm_request_threaded_irq(&pdev->dev, chip->irq, handle_eud_irq,			handle_eud_irq_thread, IRQF_ONESHOT, NULL, chip);	if (ret)		return dev_err_probe(chip->dev, ret, "failed to allocate irq\n"); 	enable_irq_wake(chip->irq); 	platform_set_drvdata(pdev, chip); 	return 0;} static void eud_remove(struct platform_device *pdev){	struct eud_chip *chip = platform_get_drvdata(pdev); 	if (chip->enabled)		disable_eud(chip); 	device_init_wakeup(&pdev->dev, false);	disable_irq_wake(chip->irq);} static const struct of_device_id eud_dt_match[] = {	{ .compatible = "qcom,eud" },	{ }};MODULE_DEVICE_TABLE(of, eud_dt_match); static struct platform_driver eud_driver = {	.probe	= eud_probe,	.remove = eud_remove,	.driver	= {		.name = "qcom_eud",		.dev_groups = eud_groups,		.of_match_table = eud_dt_match,	},};module_platform_driver(eud_driver); MODULE_DESCRIPTION("QTI EUD driver");MODULE_LICENSE("GPL v2");