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/*
* Copyright (C) 2011 Samsung Electronics Co. Ltd.
* Hyuk Kang <hyuk78.kang@samsung.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#include <linux/module.h>
#include <linux/irq.h>
#include <linux/gpio.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/kthread.h>
#include <linux/wakelock.h>
#include <linux/host_notify.h>
struct host_notifier_info {
struct host_notifier_platform_data *pdata;
struct task_struct *th;
struct wake_lock wlock;
struct delayed_work current_dwork;
wait_queue_head_t delay_wait;
int thread_remove;
int currentlimit_irq;
};
static struct host_notifier_info ninfo;
static int currentlimit_thread(void *data)
{
struct host_notifier_info *ninfo = data;
struct host_notify_dev *ndev = &ninfo->pdata->ndev;
int gpio = ninfo->pdata->gpio;
int prev = ndev->booster;
int ret = 0;
pr_info("host_notifier usbhostd: start %d\n", prev);
while (!kthread_should_stop()) {
wait_event_interruptible_timeout(ninfo->delay_wait,
ninfo->thread_remove, 1 * HZ);
ret = gpio_get_value(gpio);
if (prev != ret) {
pr_info("host_notifier usbhostd: gpio %d = %s\n",
gpio, ret ? "HIGH" : "LOW");
ndev->booster = ret ?
NOTIFY_POWER_ON : NOTIFY_POWER_OFF;
prev = ret;
if (!ret && ndev->mode == NOTIFY_HOST_MODE) {
host_state_notify(ndev,
NOTIFY_HOST_OVERCURRENT);
pr_err("host_notifier usbhostd: overcurrent\n");
break;
}
}
}
ninfo->thread_remove = 1;
pr_info("host_notifier usbhostd: exit %d\n", ret);
return 0;
}
static int start_usbhostd_thread(void)
{
if (!ninfo.th) {
pr_info("host_notifier: start usbhostd thread\n");
init_waitqueue_head(&ninfo.delay_wait);
ninfo.thread_remove = 0;
ninfo.th = kthread_run(currentlimit_thread,
&ninfo, "usbhostd");
if (IS_ERR(ninfo.th)) {
pr_err("host_notifier: Unable to start usbhostd\n");
ninfo.th = NULL;
ninfo.thread_remove = 1;
return -1;
}
host_state_notify(&ninfo.pdata->ndev, NOTIFY_HOST_ADD);
wake_lock(&ninfo.wlock);
} else
pr_info("host_notifier: usbhostd already started!\n");
return 0;
}
static int stop_usbhostd_thread(void)
{
if (ninfo.th) {
pr_info("host_notifier: stop thread\n");
if (!ninfo.thread_remove)
kthread_stop(ninfo.th);
ninfo.th = NULL;
host_state_notify(&ninfo.pdata->ndev, NOTIFY_HOST_REMOVE);
wake_unlock(&ninfo.wlock);
} else
pr_info("host_notifier: no thread\n");
return 0;
}
static int start_usbhostd_notify(void)
{
pr_info("host_notifier: start usbhostd notify\n");
host_state_notify(&ninfo.pdata->ndev, NOTIFY_HOST_ADD);
wake_lock(&ninfo.wlock);
return 0;
}
static int stop_usbhostd_notify(void)
{
pr_info("host_notifier: stop usbhostd notify\n");
host_state_notify(&ninfo.pdata->ndev, NOTIFY_HOST_REMOVE);
wake_unlock(&ninfo.wlock);
return 0;
}
static void host_notifier_booster(int enable)
{
pr_info("host_notifier: booster %s\n", enable ? "ON" : "OFF");
ninfo.pdata->booster(enable);
if (ninfo.pdata->thread_enable) {
if (enable)
start_usbhostd_thread();
else
stop_usbhostd_thread();
}
}
static irqreturn_t currentlimit_irq_thread(int irq, void *data)
{
struct host_notifier_info *hostinfo = data;
struct host_notify_dev *ndev = &hostinfo->pdata->ndev;
int gpio = hostinfo->pdata->gpio;
int prev = ndev->booster;
int ret = 0;
ret = gpio_get_value(gpio);
pr_info("currentlimit_irq_thread gpio : %d, value : %d\n", gpio, ret);
if (prev != ret) {
pr_info("host_notifier currentlimit_irq_thread: gpio %d = %s\n",
gpio, ret ? "HIGH" : "LOW");
ndev->booster = ret ?
NOTIFY_POWER_ON : NOTIFY_POWER_OFF;
prev = ret;
if (!ret && ndev->mode == NOTIFY_HOST_MODE) {
host_state_notify(ndev,
NOTIFY_HOST_OVERCURRENT);
pr_err("host_notifier currentlimit_irq_thread: overcurrent\n");
}
}
return IRQ_HANDLED;
}
static int currentlimit_irq_init(struct host_notifier_info *hostinfo)
{
int ret = 0;
hostinfo->currentlimit_irq = gpio_to_irq(hostinfo->pdata->gpio);
ret = request_threaded_irq(hostinfo->currentlimit_irq, NULL,
currentlimit_irq_thread,
IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
"overcurrent_detect", hostinfo);
if (ret)
pr_info("host_notifier: %s return : %d\n", __func__, ret);
return ret;
}
static void currentlimit_irq_work(struct work_struct *work)
{
int retval;
struct host_notifier_info *hostinfo = container_of(work,
struct host_notifier_info, current_dwork.work);
retval = currentlimit_irq_init(hostinfo);
if (retval)
pr_err("host_notifier: %s retval : %d\n", __func__, retval);
return;
}
static int host_notifier_probe(struct platform_device *pdev)
{
int ret = 0;
if (pdev && pdev->dev.platform_data)
ninfo.pdata = pdev->dev.platform_data;
else {
pr_err("host_notifier: platform_data is null.\n");
return -ENODEV;
}
dev_info(&pdev->dev, "notifier_prove\n");
if (ninfo.pdata->thread_enable) {
ret = gpio_request(ninfo.pdata->gpio, "host_notifier");
if (ret) {
dev_err(&pdev->dev, "failed to request %d\n",
ninfo.pdata->gpio);
return -EPERM;
}
gpio_direction_input(ninfo.pdata->gpio);
dev_info(&pdev->dev, "gpio = %d\n", ninfo.pdata->gpio);
ninfo.pdata->ndev.set_booster = host_notifier_booster;
ninfo.pdata->usbhostd_start = start_usbhostd_thread;
ninfo.pdata->usbhostd_stop = stop_usbhostd_thread;
} else if (ninfo.pdata->irq_enable) {
INIT_DELAYED_WORK(&ninfo.current_dwork, currentlimit_irq_work);
schedule_delayed_work(&ninfo.current_dwork,
msecs_to_jiffies(10000));
ninfo.pdata->ndev.set_booster = host_notifier_booster;
ninfo.pdata->usbhostd_start = start_usbhostd_notify;
ninfo.pdata->usbhostd_stop = stop_usbhostd_notify;
} else {
ninfo.pdata->ndev.set_booster = host_notifier_booster;
ninfo.pdata->usbhostd_start = start_usbhostd_notify;
ninfo.pdata->usbhostd_stop = stop_usbhostd_notify;
}
ret = host_notify_dev_register(&ninfo.pdata->ndev);
if (ret < 0) {
dev_err(&pdev->dev, "Failed to host_notify_dev_register\n");
return ret;
}
wake_lock_init(&ninfo.wlock, WAKE_LOCK_SUSPEND, "hostd");
return 0;
}
static int host_notifier_remove(struct platform_device *pdev)
{
/* gpio_free(ninfo.pdata->gpio); */
host_notify_dev_unregister(&ninfo.pdata->ndev);
wake_lock_destroy(&ninfo.wlock);
return 0;
}
static struct platform_driver host_notifier_driver = {
.probe = host_notifier_probe,
.remove = host_notifier_remove,
.driver = {
.name = "host_notifier",
.owner = THIS_MODULE,
},
};
static int __init host_notifier_init(void)
{
return platform_driver_register(&host_notifier_driver);
}
static void __init host_notifier_exit(void)
{
platform_driver_unregister(&host_notifier_driver);
}
module_init(host_notifier_init);
module_exit(host_notifier_exit);
MODULE_AUTHOR("Hyuk Kang <hyuk78.kang@samsung.com>");
MODULE_DESCRIPTION("USB Host notifier");
MODULE_LICENSE("GPL");
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