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linux/drivers/misc/hisi_hikey_usb.c
Uwe Kleine-König 09ed594ee3 misc: hisi_hikey_usb: Convert to platform remove callback returning void 
The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.

To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new(), which already returns void. Eventually after all drivers
are converted, .remove_new() will be renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Acked-by: John Stultz <jstultz@google.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/8775e9573fec55c5fc04151800829e9aeafc5dda.1708508896.git.u.kleine-koenig@pengutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-05 14:28:52 +00:00

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// 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/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 void 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);
}
}
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_new = 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");
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