121 lines
2.5 KiB
C
121 lines
2.5 KiB
C
/*
|
|
* otg.c - ChipIdea USB IP core OTG driver
|
|
*
|
|
* Copyright (C) 2013 Freescale Semiconductor, Inc.
|
|
*
|
|
* Author: Peter Chen
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
|
|
/*
|
|
* This file mainly handles otgsc register, it may include OTG operation
|
|
* in the future.
|
|
*/
|
|
|
|
#include <linux/usb/otg.h>
|
|
#include <linux/usb/gadget.h>
|
|
#include <linux/usb/chipidea.h>
|
|
|
|
#include "ci.h"
|
|
#include "bits.h"
|
|
#include "otg.h"
|
|
|
|
/**
|
|
* ci_otg_role - pick role based on ID pin state
|
|
* @ci: the controller
|
|
*/
|
|
enum ci_role ci_otg_role(struct ci_hdrc *ci)
|
|
{
|
|
u32 sts = hw_read(ci, OP_OTGSC, ~0);
|
|
enum ci_role role = sts & OTGSC_ID
|
|
? CI_ROLE_GADGET
|
|
: CI_ROLE_HOST;
|
|
|
|
return role;
|
|
}
|
|
|
|
void ci_handle_vbus_change(struct ci_hdrc *ci)
|
|
{
|
|
u32 otgsc;
|
|
|
|
if (!ci->is_otg)
|
|
return;
|
|
|
|
otgsc = hw_read(ci, OP_OTGSC, ~0);
|
|
|
|
if (otgsc & OTGSC_BSV)
|
|
usb_gadget_vbus_connect(&ci->gadget);
|
|
else
|
|
usb_gadget_vbus_disconnect(&ci->gadget);
|
|
}
|
|
|
|
#define CI_VBUS_STABLE_TIMEOUT_MS 5000
|
|
static void ci_handle_id_switch(struct ci_hdrc *ci)
|
|
{
|
|
enum ci_role role = ci_otg_role(ci);
|
|
|
|
if (role != ci->role) {
|
|
dev_dbg(ci->dev, "switching from %s to %s\n",
|
|
ci_role(ci)->name, ci->roles[role]->name);
|
|
|
|
ci_role_stop(ci);
|
|
/* wait vbus lower than OTGSC_BSV */
|
|
hw_wait_reg(ci, OP_OTGSC, OTGSC_BSV, 0,
|
|
CI_VBUS_STABLE_TIMEOUT_MS);
|
|
ci_role_start(ci, role);
|
|
}
|
|
}
|
|
/**
|
|
* ci_otg_work - perform otg (vbus/id) event handle
|
|
* @work: work struct
|
|
*/
|
|
static void ci_otg_work(struct work_struct *work)
|
|
{
|
|
struct ci_hdrc *ci = container_of(work, struct ci_hdrc, work);
|
|
|
|
if (ci->id_event) {
|
|
ci->id_event = false;
|
|
ci_handle_id_switch(ci);
|
|
} else if (ci->b_sess_valid_event) {
|
|
ci->b_sess_valid_event = false;
|
|
ci_handle_vbus_change(ci);
|
|
} else
|
|
dev_err(ci->dev, "unexpected event occurs at %s\n", __func__);
|
|
|
|
enable_irq(ci->irq);
|
|
}
|
|
|
|
|
|
/**
|
|
* ci_hdrc_otg_init - initialize otg struct
|
|
* ci: the controller
|
|
*/
|
|
int ci_hdrc_otg_init(struct ci_hdrc *ci)
|
|
{
|
|
INIT_WORK(&ci->work, ci_otg_work);
|
|
ci->wq = create_singlethread_workqueue("ci_otg");
|
|
if (!ci->wq) {
|
|
dev_err(ci->dev, "can't create workqueue\n");
|
|
return -ENODEV;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* ci_hdrc_otg_destroy - destroy otg struct
|
|
* ci: the controller
|
|
*/
|
|
void ci_hdrc_otg_destroy(struct ci_hdrc *ci)
|
|
{
|
|
if (ci->wq) {
|
|
flush_workqueue(ci->wq);
|
|
destroy_workqueue(ci->wq);
|
|
}
|
|
ci_disable_otg_interrupt(ci, OTGSC_INT_EN_BITS);
|
|
ci_clear_otg_interrupt(ci, OTGSC_INT_STATUS_BITS);
|
|
}
|