1 files changed, 277 insertions, 0 deletions

diff --git a/drivers/misc/hisi_hikey_usb.c b/drivers/misc/hisi_hikey_usb.c
new file mode 100644
index 000000000..2165ec35a
--- /dev/null
+++ b/drivers/misc/hisi_hikey_usb.c
@@ -0,0 +1,277 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Support for usb functionality of Hikey series boards
+ * based on Hisilicon Kirin Soc.
+ *
+ * Copyright (C) 2017-2018 Hilisicon Electronics Co., Ltd.
+ *		http://www.huawei.com
+ *
+ * Authors: Yu Chen <chenyu56@huawei.com>
+ */
+
+#include <linux/gpio/consumer.h>
+#include <linux/kernel.h>
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/notifier.h>
+#include <linux/of_gpio.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+#include <linux/usb/role.h>
+
+#define DEVICE_DRIVER_NAME "hisi_hikey_usb"
+
+#define HUB_VBUS_POWER_ON 1
+#define HUB_VBUS_POWER_OFF 0
+#define USB_SWITCH_TO_HUB 1
+#define USB_SWITCH_TO_TYPEC 0
+#define TYPEC_VBUS_POWER_ON 1
+#define TYPEC_VBUS_POWER_OFF 0
+
+struct hisi_hikey_usb {
+	struct device *dev;
+	struct gpio_desc *otg_switch;
+	struct gpio_desc *typec_vbus;
+	struct gpio_desc *reset;
+
+	struct regulator *regulator;
+
+	struct usb_role_switch *hub_role_sw;
+
+	struct usb_role_switch *dev_role_sw;
+	enum usb_role role;
+
+	struct mutex lock;
+	struct work_struct work;
+
+	struct notifier_block nb;
+};
+
+static void hub_power_ctrl(struct hisi_hikey_usb *hisi_hikey_usb, int value)
+{
+	int ret, status;
+
+	if (!hisi_hikey_usb->regulator)
+		return;
+
+	status = regulator_is_enabled(hisi_hikey_usb->regulator);
+	if (status == !!value)
+		return;
+
+	if (value)
+		ret = regulator_enable(hisi_hikey_usb->regulator);
+	else
+		ret = regulator_disable(hisi_hikey_usb->regulator);
+
+	if (ret)
+		dev_err(hisi_hikey_usb->dev,
+			"Can't switch regulator state to %s\n",
+			value ? "enabled" : "disabled");
+}
+
+static void usb_switch_ctrl(struct hisi_hikey_usb *hisi_hikey_usb,
+			    int switch_to)
+{
+	if (!hisi_hikey_usb->otg_switch)
+		return;
+
+	gpiod_set_value_cansleep(hisi_hikey_usb->otg_switch, switch_to);
+}
+
+static void usb_typec_power_ctrl(struct hisi_hikey_usb *hisi_hikey_usb,
+				 int value)
+{
+	if (!hisi_hikey_usb->typec_vbus)
+		return;
+
+	gpiod_set_value_cansleep(hisi_hikey_usb->typec_vbus, value);
+}
+
+static void relay_set_role_switch(struct work_struct *work)
+{
+	struct hisi_hikey_usb *hisi_hikey_usb = container_of(work,
+							struct hisi_hikey_usb,
+							work);
+	struct usb_role_switch *sw;
+	enum usb_role role;
+
+	if (!hisi_hikey_usb || !hisi_hikey_usb->dev_role_sw)
+		return;
+
+	mutex_lock(&hisi_hikey_usb->lock);
+	switch (hisi_hikey_usb->role) {
+	case USB_ROLE_NONE:
+		usb_typec_power_ctrl(hisi_hikey_usb, TYPEC_VBUS_POWER_OFF);
+		usb_switch_ctrl(hisi_hikey_usb, USB_SWITCH_TO_HUB);
+		hub_power_ctrl(hisi_hikey_usb, HUB_VBUS_POWER_ON);
+		break;
+	case USB_ROLE_HOST:
+		hub_power_ctrl(hisi_hikey_usb, HUB_VBUS_POWER_OFF);
+		usb_switch_ctrl(hisi_hikey_usb, USB_SWITCH_TO_TYPEC);
+		usb_typec_power_ctrl(hisi_hikey_usb, TYPEC_VBUS_POWER_ON);
+		break;
+	case USB_ROLE_DEVICE:
+		hub_power_ctrl(hisi_hikey_usb, HUB_VBUS_POWER_OFF);
+		usb_typec_power_ctrl(hisi_hikey_usb, TYPEC_VBUS_POWER_OFF);
+		usb_switch_ctrl(hisi_hikey_usb, USB_SWITCH_TO_TYPEC);
+		break;
+	default:
+		break;
+	}
+	sw = hisi_hikey_usb->dev_role_sw;
+	role = hisi_hikey_usb->role;
+	mutex_unlock(&hisi_hikey_usb->lock);
+
+	usb_role_switch_set_role(sw, role);
+}
+
+static int hub_usb_role_switch_set(struct usb_role_switch *sw, enum usb_role role)
+{
+	struct hisi_hikey_usb *hisi_hikey_usb = usb_role_switch_get_drvdata(sw);
+
+	if (!hisi_hikey_usb || !hisi_hikey_usb->dev_role_sw)
+		return -EINVAL;
+
+	mutex_lock(&hisi_hikey_usb->lock);
+	hisi_hikey_usb->role = role;
+	mutex_unlock(&hisi_hikey_usb->lock);
+
+	schedule_work(&hisi_hikey_usb->work);
+
+	return 0;
+}
+
+static int hisi_hikey_usb_of_role_switch(struct platform_device *pdev,
+					 struct hisi_hikey_usb *hisi_hikey_usb)
+{
+	struct device *dev = &pdev->dev;
+	struct usb_role_switch_desc hub_role_switch = {NULL};
+
+	if (!device_property_read_bool(dev, "usb-role-switch"))
+		return 0;
+
+	hisi_hikey_usb->otg_switch = devm_gpiod_get(dev, "otg-switch",
+						    GPIOD_OUT_HIGH);
+	if (IS_ERR(hisi_hikey_usb->otg_switch)) {
+		dev_err(dev, "get otg-switch failed with error %ld\n",
+			PTR_ERR(hisi_hikey_usb->otg_switch));
+		return PTR_ERR(hisi_hikey_usb->otg_switch);
+	}
+
+	hisi_hikey_usb->typec_vbus = devm_gpiod_get(dev, "typec-vbus",
+						    GPIOD_OUT_LOW);
+	if (IS_ERR(hisi_hikey_usb->typec_vbus)) {
+		dev_err(dev, "get typec-vbus failed with error %ld\n",
+			PTR_ERR(hisi_hikey_usb->typec_vbus));
+		return PTR_ERR(hisi_hikey_usb->typec_vbus);
+	}
+
+	hisi_hikey_usb->reset = devm_gpiod_get_optional(dev,
+							"hub-reset-en",
+							GPIOD_OUT_HIGH);
+	if (IS_ERR(hisi_hikey_usb->reset)) {
+		dev_err(dev, "get hub-reset-en failed with error %ld\n",
+			PTR_ERR(hisi_hikey_usb->reset));
+		return PTR_ERR(hisi_hikey_usb->reset);
+	}
+
+	hisi_hikey_usb->dev_role_sw = usb_role_switch_get(dev);
+	if (!hisi_hikey_usb->dev_role_sw)
+		return -EPROBE_DEFER;
+	if (IS_ERR(hisi_hikey_usb->dev_role_sw)) {
+		dev_err(dev, "get device role switch failed with error %ld\n",
+			PTR_ERR(hisi_hikey_usb->dev_role_sw));
+		return PTR_ERR(hisi_hikey_usb->dev_role_sw);
+	}
+
+	INIT_WORK(&hisi_hikey_usb->work, relay_set_role_switch);
+
+	hub_role_switch.fwnode = dev_fwnode(dev);
+	hub_role_switch.set = hub_usb_role_switch_set;
+	hub_role_switch.driver_data = hisi_hikey_usb;
+
+	hisi_hikey_usb->hub_role_sw = usb_role_switch_register(dev,
+							       &hub_role_switch);
+
+	if (IS_ERR(hisi_hikey_usb->hub_role_sw)) {
+		dev_err(dev,
+			"failed to register hub role with error %ld\n",
+			PTR_ERR(hisi_hikey_usb->hub_role_sw));
+		usb_role_switch_put(hisi_hikey_usb->dev_role_sw);
+		return PTR_ERR(hisi_hikey_usb->hub_role_sw);
+	}
+
+	return 0;
+}
+
+static int hisi_hikey_usb_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct hisi_hikey_usb *hisi_hikey_usb;
+	int ret;
+
+	hisi_hikey_usb = devm_kzalloc(dev, sizeof(*hisi_hikey_usb), GFP_KERNEL);
+	if (!hisi_hikey_usb)
+		return -ENOMEM;
+
+	hisi_hikey_usb->dev = &pdev->dev;
+	mutex_init(&hisi_hikey_usb->lock);
+
+	hisi_hikey_usb->regulator = devm_regulator_get(dev, "hub-vdd");
+	if (IS_ERR(hisi_hikey_usb->regulator)) {
+		if (PTR_ERR(hisi_hikey_usb->regulator) == -EPROBE_DEFER) {
+			dev_info(dev, "waiting for hub-vdd-supply\n");
+			return PTR_ERR(hisi_hikey_usb->regulator);
+		}
+		dev_err(dev, "get hub-vdd-supply failed with error %ld\n",
+			PTR_ERR(hisi_hikey_usb->regulator));
+		return PTR_ERR(hisi_hikey_usb->regulator);
+	}
+
+	ret = hisi_hikey_usb_of_role_switch(pdev, hisi_hikey_usb);
+	if (ret)
+		return ret;
+
+	platform_set_drvdata(pdev, hisi_hikey_usb);
+
+	return 0;
+}
+
+static int  hisi_hikey_usb_remove(struct platform_device *pdev)
+{
+	struct hisi_hikey_usb *hisi_hikey_usb = platform_get_drvdata(pdev);
+
+	if (hisi_hikey_usb->hub_role_sw) {
+		usb_role_switch_unregister(hisi_hikey_usb->hub_role_sw);
+
+		if (hisi_hikey_usb->dev_role_sw)
+			usb_role_switch_put(hisi_hikey_usb->dev_role_sw);
+	} else {
+		hub_power_ctrl(hisi_hikey_usb, HUB_VBUS_POWER_OFF);
+	}
+
+	return 0;
+}
+
+static const struct of_device_id id_table_hisi_hikey_usb[] = {
+	{ .compatible = "hisilicon,usbhub" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, id_table_hisi_hikey_usb);
+
+static struct platform_driver hisi_hikey_usb_driver = {
+	.probe = hisi_hikey_usb_probe,
+	.remove = hisi_hikey_usb_remove,
+	.driver = {
+		.name = DEVICE_DRIVER_NAME,
+		.of_match_table = id_table_hisi_hikey_usb,
+	},
+};
+
+module_platform_driver(hisi_hikey_usb_driver);
+
+MODULE_AUTHOR("Yu Chen <chenyu56@huawei.com>");
+MODULE_DESCRIPTION("Driver Support for USB functionality of Hikey");
+MODULE_LICENSE("GPL v2");