cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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hisi_hikey_usb.c (7432B)


      1// SPDX-License-Identifier: GPL-2.0
      2/*
      3 * Support for usb functionality of Hikey series boards
      4 * based on Hisilicon Kirin Soc.
      5 *
      6 * Copyright (C) 2017-2018 Hilisicon Electronics Co., Ltd.
      7 *		http://www.huawei.com
      8 *
      9 * Authors: Yu Chen <chenyu56@huawei.com>
     10 */
     11
     12#include <linux/gpio/consumer.h>
     13#include <linux/kernel.h>
     14#include <linux/mod_devicetable.h>
     15#include <linux/module.h>
     16#include <linux/notifier.h>
     17#include <linux/of_gpio.h>
     18#include <linux/platform_device.h>
     19#include <linux/property.h>
     20#include <linux/regulator/consumer.h>
     21#include <linux/slab.h>
     22#include <linux/usb/role.h>
     23
     24#define DEVICE_DRIVER_NAME "hisi_hikey_usb"
     25
     26#define HUB_VBUS_POWER_ON 1
     27#define HUB_VBUS_POWER_OFF 0
     28#define USB_SWITCH_TO_HUB 1
     29#define USB_SWITCH_TO_TYPEC 0
     30#define TYPEC_VBUS_POWER_ON 1
     31#define TYPEC_VBUS_POWER_OFF 0
     32
     33struct hisi_hikey_usb {
     34	struct device *dev;
     35	struct gpio_desc *otg_switch;
     36	struct gpio_desc *typec_vbus;
     37	struct gpio_desc *reset;
     38
     39	struct regulator *regulator;
     40
     41	struct usb_role_switch *hub_role_sw;
     42
     43	struct usb_role_switch *dev_role_sw;
     44	enum usb_role role;
     45
     46	struct mutex lock;
     47	struct work_struct work;
     48
     49	struct notifier_block nb;
     50};
     51
     52static void hub_power_ctrl(struct hisi_hikey_usb *hisi_hikey_usb, int value)
     53{
     54	int ret, status;
     55
     56	if (!hisi_hikey_usb->regulator)
     57		return;
     58
     59	status = regulator_is_enabled(hisi_hikey_usb->regulator);
     60	if (status == !!value)
     61		return;
     62
     63	if (value)
     64		ret = regulator_enable(hisi_hikey_usb->regulator);
     65	else
     66		ret = regulator_disable(hisi_hikey_usb->regulator);
     67
     68	if (ret)
     69		dev_err(hisi_hikey_usb->dev,
     70			"Can't switch regulator state to %s\n",
     71			value ? "enabled" : "disabled");
     72}
     73
     74static void usb_switch_ctrl(struct hisi_hikey_usb *hisi_hikey_usb,
     75			    int switch_to)
     76{
     77	if (!hisi_hikey_usb->otg_switch)
     78		return;
     79
     80	gpiod_set_value_cansleep(hisi_hikey_usb->otg_switch, switch_to);
     81}
     82
     83static void usb_typec_power_ctrl(struct hisi_hikey_usb *hisi_hikey_usb,
     84				 int value)
     85{
     86	if (!hisi_hikey_usb->typec_vbus)
     87		return;
     88
     89	gpiod_set_value_cansleep(hisi_hikey_usb->typec_vbus, value);
     90}
     91
     92static void relay_set_role_switch(struct work_struct *work)
     93{
     94	struct hisi_hikey_usb *hisi_hikey_usb = container_of(work,
     95							struct hisi_hikey_usb,
     96							work);
     97	struct usb_role_switch *sw;
     98	enum usb_role role;
     99
    100	if (!hisi_hikey_usb || !hisi_hikey_usb->dev_role_sw)
    101		return;
    102
    103	mutex_lock(&hisi_hikey_usb->lock);
    104	switch (hisi_hikey_usb->role) {
    105	case USB_ROLE_NONE:
    106		usb_typec_power_ctrl(hisi_hikey_usb, TYPEC_VBUS_POWER_OFF);
    107		usb_switch_ctrl(hisi_hikey_usb, USB_SWITCH_TO_HUB);
    108		hub_power_ctrl(hisi_hikey_usb, HUB_VBUS_POWER_ON);
    109		break;
    110	case USB_ROLE_HOST:
    111		hub_power_ctrl(hisi_hikey_usb, HUB_VBUS_POWER_OFF);
    112		usb_switch_ctrl(hisi_hikey_usb, USB_SWITCH_TO_TYPEC);
    113		usb_typec_power_ctrl(hisi_hikey_usb, TYPEC_VBUS_POWER_ON);
    114		break;
    115	case USB_ROLE_DEVICE:
    116		hub_power_ctrl(hisi_hikey_usb, HUB_VBUS_POWER_OFF);
    117		usb_typec_power_ctrl(hisi_hikey_usb, TYPEC_VBUS_POWER_OFF);
    118		usb_switch_ctrl(hisi_hikey_usb, USB_SWITCH_TO_TYPEC);
    119		break;
    120	default:
    121		break;
    122	}
    123	sw = hisi_hikey_usb->dev_role_sw;
    124	role = hisi_hikey_usb->role;
    125	mutex_unlock(&hisi_hikey_usb->lock);
    126
    127	usb_role_switch_set_role(sw, role);
    128}
    129
    130static int hub_usb_role_switch_set(struct usb_role_switch *sw, enum usb_role role)
    131{
    132	struct hisi_hikey_usb *hisi_hikey_usb = usb_role_switch_get_drvdata(sw);
    133
    134	if (!hisi_hikey_usb || !hisi_hikey_usb->dev_role_sw)
    135		return -EINVAL;
    136
    137	mutex_lock(&hisi_hikey_usb->lock);
    138	hisi_hikey_usb->role = role;
    139	mutex_unlock(&hisi_hikey_usb->lock);
    140
    141	schedule_work(&hisi_hikey_usb->work);
    142
    143	return 0;
    144}
    145
    146static int hisi_hikey_usb_of_role_switch(struct platform_device *pdev,
    147					 struct hisi_hikey_usb *hisi_hikey_usb)
    148{
    149	struct device *dev = &pdev->dev;
    150	struct usb_role_switch_desc hub_role_switch = {NULL};
    151
    152	if (!device_property_read_bool(dev, "usb-role-switch"))
    153		return 0;
    154
    155	hisi_hikey_usb->otg_switch = devm_gpiod_get(dev, "otg-switch",
    156						    GPIOD_OUT_HIGH);
    157	if (IS_ERR(hisi_hikey_usb->otg_switch)) {
    158		dev_err(dev, "get otg-switch failed with error %ld\n",
    159			PTR_ERR(hisi_hikey_usb->otg_switch));
    160		return PTR_ERR(hisi_hikey_usb->otg_switch);
    161	}
    162
    163	hisi_hikey_usb->typec_vbus = devm_gpiod_get(dev, "typec-vbus",
    164						    GPIOD_OUT_LOW);
    165	if (IS_ERR(hisi_hikey_usb->typec_vbus)) {
    166		dev_err(dev, "get typec-vbus failed with error %ld\n",
    167			PTR_ERR(hisi_hikey_usb->typec_vbus));
    168		return PTR_ERR(hisi_hikey_usb->typec_vbus);
    169	}
    170
    171	hisi_hikey_usb->reset = devm_gpiod_get_optional(dev,
    172							"hub-reset-en",
    173							GPIOD_OUT_HIGH);
    174	if (IS_ERR(hisi_hikey_usb->reset)) {
    175		dev_err(dev, "get hub-reset-en failed with error %ld\n",
    176			PTR_ERR(hisi_hikey_usb->reset));
    177		return PTR_ERR(hisi_hikey_usb->reset);
    178	}
    179
    180	hisi_hikey_usb->dev_role_sw = usb_role_switch_get(dev);
    181	if (!hisi_hikey_usb->dev_role_sw)
    182		return -EPROBE_DEFER;
    183	if (IS_ERR(hisi_hikey_usb->dev_role_sw)) {
    184		dev_err(dev, "get device role switch failed with error %ld\n",
    185			PTR_ERR(hisi_hikey_usb->dev_role_sw));
    186		return PTR_ERR(hisi_hikey_usb->dev_role_sw);
    187	}
    188
    189	INIT_WORK(&hisi_hikey_usb->work, relay_set_role_switch);
    190
    191	hub_role_switch.fwnode = dev_fwnode(dev);
    192	hub_role_switch.set = hub_usb_role_switch_set;
    193	hub_role_switch.driver_data = hisi_hikey_usb;
    194
    195	hisi_hikey_usb->hub_role_sw = usb_role_switch_register(dev,
    196							       &hub_role_switch);
    197
    198	if (IS_ERR(hisi_hikey_usb->hub_role_sw)) {
    199		dev_err(dev,
    200			"failed to register hub role with error %ld\n",
    201			PTR_ERR(hisi_hikey_usb->hub_role_sw));
    202		usb_role_switch_put(hisi_hikey_usb->dev_role_sw);
    203		return PTR_ERR(hisi_hikey_usb->hub_role_sw);
    204	}
    205
    206	return 0;
    207}
    208
    209static int hisi_hikey_usb_probe(struct platform_device *pdev)
    210{
    211	struct device *dev = &pdev->dev;
    212	struct hisi_hikey_usb *hisi_hikey_usb;
    213	int ret;
    214
    215	hisi_hikey_usb = devm_kzalloc(dev, sizeof(*hisi_hikey_usb), GFP_KERNEL);
    216	if (!hisi_hikey_usb)
    217		return -ENOMEM;
    218
    219	hisi_hikey_usb->dev = &pdev->dev;
    220	mutex_init(&hisi_hikey_usb->lock);
    221
    222	hisi_hikey_usb->regulator = devm_regulator_get(dev, "hub-vdd");
    223	if (IS_ERR(hisi_hikey_usb->regulator)) {
    224		if (PTR_ERR(hisi_hikey_usb->regulator) == -EPROBE_DEFER) {
    225			dev_info(dev, "waiting for hub-vdd-supply\n");
    226			return PTR_ERR(hisi_hikey_usb->regulator);
    227		}
    228		dev_err(dev, "get hub-vdd-supply failed with error %ld\n",
    229			PTR_ERR(hisi_hikey_usb->regulator));
    230		return PTR_ERR(hisi_hikey_usb->regulator);
    231	}
    232
    233	ret = hisi_hikey_usb_of_role_switch(pdev, hisi_hikey_usb);
    234	if (ret)
    235		return ret;
    236
    237	platform_set_drvdata(pdev, hisi_hikey_usb);
    238
    239	return 0;
    240}
    241
    242static int  hisi_hikey_usb_remove(struct platform_device *pdev)
    243{
    244	struct hisi_hikey_usb *hisi_hikey_usb = platform_get_drvdata(pdev);
    245
    246	if (hisi_hikey_usb->hub_role_sw) {
    247		usb_role_switch_unregister(hisi_hikey_usb->hub_role_sw);
    248
    249		if (hisi_hikey_usb->dev_role_sw)
    250			usb_role_switch_put(hisi_hikey_usb->dev_role_sw);
    251	} else {
    252		hub_power_ctrl(hisi_hikey_usb, HUB_VBUS_POWER_OFF);
    253	}
    254
    255	return 0;
    256}
    257
    258static const struct of_device_id id_table_hisi_hikey_usb[] = {
    259	{ .compatible = "hisilicon,usbhub" },
    260	{}
    261};
    262MODULE_DEVICE_TABLE(of, id_table_hisi_hikey_usb);
    263
    264static struct platform_driver hisi_hikey_usb_driver = {
    265	.probe = hisi_hikey_usb_probe,
    266	.remove = hisi_hikey_usb_remove,
    267	.driver = {
    268		.name = DEVICE_DRIVER_NAME,
    269		.of_match_table = id_table_hisi_hikey_usb,
    270	},
    271};
    272
    273module_platform_driver(hisi_hikey_usb_driver);
    274
    275MODULE_AUTHOR("Yu Chen <chenyu56@huawei.com>");
    276MODULE_DESCRIPTION("Driver Support for USB functionality of Hikey");
    277MODULE_LICENSE("GPL v2");