linux/drivers/usb/dwc3/drd.c

75 lines
1.5 KiB
C

// SPDX-License-Identifier: GPL-2.0
/**
* drd.c - DesignWare USB3 DRD Controller Dual-role support
*
* Copyright (C) 2017 Texas Instruments Incorporated - http://www.ti.com
*
* Authors: Roger Quadros <rogerq@ti.com>
*/
#include <linux/extcon.h>
#include "debug.h"
#include "core.h"
#include "gadget.h"
static void dwc3_drd_update(struct dwc3 *dwc)
{
int id;
id = extcon_get_state(dwc->edev, EXTCON_USB_HOST);
if (id < 0)
id = 0;
dwc3_set_mode(dwc, id ?
DWC3_GCTL_PRTCAP_HOST :
DWC3_GCTL_PRTCAP_DEVICE);
}
static int dwc3_drd_notifier(struct notifier_block *nb,
unsigned long event, void *ptr)
{
struct dwc3 *dwc = container_of(nb, struct dwc3, edev_nb);
dwc3_set_mode(dwc, event ?
DWC3_GCTL_PRTCAP_HOST :
DWC3_GCTL_PRTCAP_DEVICE);
return NOTIFY_DONE;
}
int dwc3_drd_init(struct dwc3 *dwc)
{
int ret;
if (dwc->dev->of_node) {
if (of_property_read_bool(dwc->dev->of_node, "extcon"))
dwc->edev = extcon_get_edev_by_phandle(dwc->dev, 0);
if (IS_ERR(dwc->edev))
return PTR_ERR(dwc->edev);
dwc->edev_nb.notifier_call = dwc3_drd_notifier;
ret = extcon_register_notifier(dwc->edev, EXTCON_USB_HOST,
&dwc->edev_nb);
if (ret < 0) {
dev_err(dwc->dev, "couldn't register cable notifier\n");
return ret;
}
}
dwc3_drd_update(dwc);
return 0;
}
void dwc3_drd_exit(struct dwc3 *dwc)
{
extcon_unregister_notifier(dwc->edev, EXTCON_USB_HOST,
&dwc->edev_nb);
dwc3_set_mode(dwc, DWC3_GCTL_PRTCAP_DEVICE);
flush_work(&dwc->drd_work);
dwc3_gadget_exit(dwc);
}