Re: [PATCH 1/2] gadget: Introduce the usb charger framework

From: Baolin Wang
Date: Fri Aug 07 2015 - 04:33:56 EST


On 7 August 2015 at 13:41, Peter Chen <peter.chen@xxxxxxxxxxxxx> wrote:
> On Thu, Aug 06, 2015 at 03:03:48PM +0800, Baolin Wang wrote:
>> This patch introduces the usb charger driver based on usb gadget that
>> makes an enhancement to a power driver. It works well in practice but
>> that requires a system with suitable hardware.
>>
>> The basic conception of the usb charger is that, when one usb charger
>> is added or removed by reporting from the usb gadget state change or
>> the extcon device state change, the usb charger will report to power
>> user to set the current limitation.
>>
>> The usb charger will register notifiees on the usb gadget or the extcon
>> device to get notified the usb charger state.
>>
>> Power user will register a notifiee on the usb charger to get notified
>> by status changes from the usb charger. It will report to power user
>> to set the current limitation when detecting the usb charger is added
>> or removed from extcon device state or usb gadget state.
>>
>> Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxx>
>> ---
>> drivers/usb/gadget/charger.c | 547 +++++++++++++++++++++++++++++++++++++++
>> include/linux/usb/usb_charger.h | 101 ++++++++
>> 2 files changed, 648 insertions(+)
>> create mode 100644 drivers/usb/gadget/charger.c
>> create mode 100644 include/linux/usb/usb_charger.h
>>
>> diff --git a/drivers/usb/gadget/charger.c b/drivers/usb/gadget/charger.c
>> new file mode 100644
>> index 0000000..3ca0180
>> --- /dev/null
>> +++ b/drivers/usb/gadget/charger.c
>> @@ -0,0 +1,547 @@
>> +/*
>> + * usb charger.c -- USB charger driver
>> + *
>> + * 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/device.h>
>> +#include <linux/err.h>
>> +#include <linux/extcon.h>
>> +#include <linux/export.h>
>> +#include <linux/kernel.h>
>> +#include <linux/module.h>
>> +#include <linux/of.h>
>> +#include <linux/of_device.h>
>> +#include <linux/of_address.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/slab.h>
>> +#include <linux/usb.h>
>> +#include <linux/usb/ch9.h>
>> +#include <linux/usb/gadget.h>
>> +#include <linux/usb/usb_charger.h>
>> +
>> +#define DEFAULT_CUR_PROTECT (50)
>> +#define DEFAULT_SDP_CUR_LIMIT (500 - DEFAULT_CUR_PROTECT)
>> +#define DEFAULT_DCP_CUR_LIMIT (1500 - DEFAULT_CUR_PROTECT)
>> +#define DEFAULT_CDP_CUR_LIMIT (1500 - DEFAULT_CUR_PROTECT)
>> +#define DEFAULT_ACA_CUR_LIMIT (1500 - DEFAULT_CUR_PROTECT)
>> +
>> +static LIST_HEAD(usb_charger_list);
>> +static DEFINE_MUTEX(usb_charger_list_lock);
>> +
>> +/*
>> + * usb_charger_find_by_name - Get the usb charger device by name.
>> + * @name - usb charger device name.
>> + *
>> + * notes: when this function walks the list and returns a charger
>> + * it's dropped the lock which means that something else could come
>> + * along and delete the charger before we dereference the pointer.
>> + * It's very unlikely but it's a possibility so you should take care
>> + * of it.
>> + * Thus when you get the usb charger by name, you should call
>> + * put_usb_charger() to derease the reference count of the usb charger.
>> + *
>> + * return the instance of usb charger device.
>> + */
>> +struct usb_charger *usb_charger_find_by_name(char *name)
>> +{
>> + struct usb_charger *uchger;
>> +
>> + if (!name)
>> + return ERR_PTR(-EINVAL);
>> +
>> + mutex_lock(&usb_charger_list_lock);
>> + list_for_each_entry(uchger, &usb_charger_list, entry) {
>> + if (!strcmp(uchger->name, name)) {
>> + get_usb_charger(uchger);
>> + mutex_unlock(&usb_charger_list_lock);
>> + return uchger;
>> + }
>> + }
>> + mutex_unlock(&usb_charger_list_lock);
>> +
>> + return NULL;
>> +}
>> +
>> +/*
>> + * usb_charger_register_notify() - Register a notifiee to get notified by
>> + * any attach status changes from the usb charger type detection.
>> + * @uchger - the usb charger device which is monitored.
>> + * @nb - a notifier block to be registered.
>> + */
>> +void usb_charger_register_notify(struct usb_charger *uchger,
>> + struct notifier_block *nb)
>> +{
>> + unsigned long flags;
>> +
>> + spin_lock_irqsave(&uchger->lock, flags);
>> + raw_notifier_chain_register(&uchger->uchger_nh, nb);
>> + spin_unlock_irqrestore(&uchger->lock, flags);
>> +}
>> +
>> +/*
>> + * usb_charger_unregister_notify() - Unregister a notifiee from the usb charger.
>> + * @uchger - the usb charger device which is monitored.
>> + * @nb - a notifier block to be unregistered.
>> + */
>> +void usb_charger_unregister_notify(struct usb_charger *uchger,
>> + struct notifier_block *nb)
>> +{
>> + unsigned long flags;
>> +
>> + spin_lock_irqsave(&uchger->lock, flags);
>> + raw_notifier_chain_unregister(&uchger->uchger_nh, nb);
>> + spin_unlock_irqrestore(&uchger->lock, flags);
>> +}
>> +
>> +/*
>> + * usb_charger_register_extcon_notifier() - Register a notifiee of the usb
>> + * charger to get notified by any attach status changes from
>> + * the extcon device.
>> + * @uchger - the usb charger device.
>> + * @edev - the extcon device.
>> + * @extcon_id - extcon id.
>> + */
>> +int usb_charger_register_extcon_notifier(struct usb_charger *uchger,
>> + struct extcon_dev *edev,
>> + unsigned int extcon_id)
>> +{
>> + if (!uchger || !edev)
>> + return -EINVAL;
>> +
>> + return extcon_register_notifier(edev, extcon_id, &uchger->extcon_nb.nb);
>> +}
>> +
>> +/*
>> + * usb_charger_unregister_extcon_notifier() - Unregister a notifiee of the
>> + * usb charger from the extcon device.
>> + * @uchger - the usb charger device.
>> + * @edev - the extcon device.
>> + * @extcon_id - extcon id.
>> + */
>> +int usb_charger_unregister_extcon_notifier(struct usb_charger *uchger,
>> + struct extcon_dev *edev,
>> + unsigned int extcon_id)
>> +{
>> + if (!uchger || !edev)
>> + return -EINVAL;
>> +
>> + return extcon_unregister_notifier(edev, extcon_id, &uchger->extcon_nb.nb);
>> +}
>> +
>> +/*
>> + * usb_charger_register_gadget_notifier() - Register a notifiee of the usb
>> + * charger to get notified by any attach status changes from
>> + * the usb gadget device.
>> + * @uchger - the usb charger device.
>> + */
>> +int usb_charger_register_gadget_notifier(struct usb_charger *uchger)
>> +{
>> + struct usb_gadget *ugadget = uchger->gadget;
>> +
>> + return usb_gadget_register_notify(ugadget, &uchger->gadget_nb);
>> +}
>
> usb_gadget_register_notify is defined at your 2nd patch, it will
> cause 'git bisect' problem.
>

Oh, I miss that and will fix that.

>> +
>> +/*
>> + * usb_charger_unregister_gadget_notifier() - Unregister a notifiee of the usb
>> + * charger from the usb gadget device.
>> + * @uchger - the usb charger device.
>> + */
>> +int usb_charger_unregister_gadget_notifier(struct usb_charger *uchger)
>> +{
>> + struct usb_gadget *ugadget = uchger->gadget;
>> +
>> + return usb_gadget_unregister_notify(ugadget, &uchger->gadget_nb);
>> +}
>> +
>> +/*
>> + * usb_charger_set_cur_limit() - Set the current limitation.
>> + * @uchger - the usb charger device.
>> + * @xxx_cur - the current limit by different charger type.
>> + *
>> + */
>> +int usb_charger_set_cur_limit(struct usb_charger *uchger,
>> + struct usb_charger_cur_limit *cur_limit_set)
>> +{
>> + if (!uchger || !cur_limit_set)
>> + return -EINVAL;
>> +
>> + uchger->cur_limit.sdp_cur_limit = cur_limit_set->sdp_cur_limit;
>> + uchger->cur_limit.dcp_cur_limit = cur_limit_set->dcp_cur_limit;
>> + uchger->cur_limit.cdp_cur_limit = cur_limit_set->cdp_cur_limit;
>> + uchger->cur_limit.aca_cur_limit = cur_limit_set->aca_cur_limit;
>> + return 0;
>> +}
>> +
>> +/*
>> + * usb_charger_get_cur_limit() - Get the current limitation by different usb
>> + * charger type.
>> + * @uchger - the usb charger device.
>> + * @type - the usb charger type.
>> + *
>> + * return the current limitation to set.
>> + */
>> +static unsigned int
>> +usb_charger_get_cur_limit(struct usb_charger *uchger)
>> +{
>> + enum usb_charger_type uchger_type = uchger->type;
>> + unsigned int cur_limit;
>> +
>> + switch (uchger_type) {
>> + case SDP_TYPE:
>> + cur_limit = uchger->cur_limit.sdp_cur_limit;
>> + break;
>> + case DCP_TYPE:
>> + cur_limit = uchger->cur_limit.dcp_cur_limit;
>> + break;
>> + case CDP_TYPE:
>> + cur_limit = uchger->cur_limit.cdp_cur_limit;
>> + break;
>> + case ACA_TYPE:
>> + cur_limit = uchger->cur_limit.aca_cur_limit;
>> + break;
>> + default:
>> + return 0;
>> + }
>> +
>> + return cur_limit;
>> +}
>> +
>> +/*
>> + * usb_charger_detect_type() - Get the usb charger type by the callback which is
>> + * implemented by user.
>> + * @uchger - the usb charger device.
>> + *
>> + * return the usb charger type.
>> + */
>> +enum usb_charger_type
>> +usb_charger_detect_type(struct usb_charger *uchger)
>> +{
>> + if (uchger->gadget && uchger->gadget->ops
>> + && uchger->gadget->ops->get_charger_type)
>> + uchger->type =
>> + uchger->gadget->ops->get_charger_type(uchger->gadget);
>> + else
>> + uchger->type = UNKNOWN_TYPE;
>> +
>> + return uchger->type;
>> +}
>> +
>> +/*
>> + * usb_charger_notifier_others() - It will notify other device registered on
>> + * usb charger.
>> + * @uchger - the usb charger device.
>> + *
>> + */
>> +static void
>> +usb_charger_notify_others(struct usb_charger *uchger,
>> + enum usb_charger_state state)
>> +{
>> + unsigned long flags;
>> +
>> + spin_lock_irqsave(&uchger->lock, flags);
>
> it is better to use mutex_lock instead of disabling interrupt since
> checking charger type may cause sleeping.
>

Yes, I'll think about the lock again.

>> + uchger->state = state;
>> +
>> + switch (state) {
>> + case USB_CHARGER_PRESENT:
>> + usb_charger_detect_type(uchger);
>> + raw_notifier_call_chain(&uchger->uchger_nh,
>> + usb_charger_get_cur_limit(uchger),
>> + uchger);
>> + break;
>> + case USB_CHARGER_REMOVE:
>> + uchger->type = UNKNOWN_TYPE;
>> + raw_notifier_call_chain(&uchger->uchger_nh, 0, uchger);
>> + break;
>> + default:
>> + dev_warn(&uchger->dev, "Unknown USB charger state: %d\n",
>> + state);
>> + break;
>> + }
>> + spin_unlock_irqrestore(&uchger->lock, flags);
>> +}
>> +
>> +/*
>> + * usb_charger_plug_by_extcon() - The notifier call function which is registered
>> + * on the extcon device.
>> + * @nb - thr notifier block that notified by extcon device.
>> + * @state - the extcon device state changed.
>> + * @data - here specify a extcon device.
>> + *
>> + * return the notify flag.
>> + */
>> +static int
>> +usb_charger_plug_by_extcon(struct notifier_block *nb,
>> + unsigned long state, void *data)
>> +{
>> + struct usb_charger_nb *extcon_nb =
>> + container_of(nb, struct usb_charger_nb, nb);
>> + struct usb_charger *uchger = extcon_nb->uchger;
>> + enum usb_charger_state uchger_state;
>> +
>> + if (!uchger)
>> + return NOTIFY_BAD;
>> +
>> + /* Report event to power to setting the current limitation
>> + * for this usb charger when one usb charger is added or removed
>> + * with detecting by extcon device.
>> + */
>> + if (state)
>> + uchger_state = USB_CHARGER_PRESENT;
>> + else
>> + uchger_state = USB_CHARGER_REMOVE;
>> +
>> + usb_charger_notify_others(uchger, uchger_state);
>> +
>> + return NOTIFY_OK;
>> +}
>> +
>> +/*
>> + * usb_charger_plug_by_gadget() - Set the usb charger current limitation
>> + * according to the usb gadget device state.
>> + * @data - here specify a usb charger device.
>> + *
>> + */
>> +static int
>> +usb_charger_plug_by_gadget(struct notifier_block *nb,
>> + unsigned long state, void *data)
>> +{
>> + struct usb_gadget *gadget = (struct usb_gadget *)data;
>> + struct usb_charger *uchger = gadget->uchger;
>> + enum usb_charger_state uchger_state;
>> +
>> + if (!uchger)
>> + return NOTIFY_BAD;
>> +
>> + /* Report event to power to setting the current limitation
>> + * for this usb charger when one usb charger state is changed
>> + * with detecting by usb gadget state.
>> + */
>> + if (uchger->old_gadget_state != state) {
>> + uchger->old_gadget_state = state;
>> +
>> + if (state >= USB_STATE_ATTACHED)
>> + uchger_state = USB_CHARGER_PRESENT;
>> + else if (state == USB_STATE_NOTATTACHED)
>> + uchger_state = USB_CHARGER_REMOVE;
>> + else
>> + uchger_state = USB_CHARGER_DEFAULT;
>> +
>> + usb_charger_notify_others(uchger, uchger_state);
>> + }
>> +
>> + return NOTIFY_OK;
>> +}
>> +
>> +static int devm_uchger_dev_match(struct device *dev, void *res, void *data)
>> +{
>> + struct usb_charger **r = res;
>> +
>> + if (WARN_ON(!r || !*r))
>> + return 0;
>> +
>> + return *r == data;
>> +}
>> +
>> +static void usb_charger_release(struct device *dev)
>> +{
>> + struct usb_charger *uchger = dev_get_drvdata(dev);
>> +
>> + if (!atomic_dec_and_test(&uchger->count)) {
>> + dev_err(dev, "The usb charger is still in use\n");
>> + return;
>> + }
>> +
>> + kfree(uchger->name);
>> + kfree(uchger);
>> +}
>> +
>> +/*
>> + * usb_charger_unregister() - Unregister a usb charger device.
>> + * @uchger - the usb charger device.
>> + *
>> + */
>> +int usb_charger_unregister(struct usb_charger *uchger)
>> +{
>> + if (!uchger)
>> + return -EINVAL;
>> +
>> + mutex_lock(&usb_charger_list_lock);
>> + list_del(&uchger->entry);
>> + mutex_unlock(&usb_charger_list_lock);
>> +
>> + device_unregister(&uchger->dev);
>> + return 0;
>> +}
>> +
>> +static void devm_uchger_dev_unreg(struct device *dev, void *res)
>> +{
>> + usb_charger_unregister(*(struct usb_charger **)res);
>> +}
>> +
>> +void devm_usb_charger_unregister(struct device *dev,
>> + struct usb_charger *uchger)
>> +{
>> + devres_release(dev, devm_uchger_dev_unreg,
>> + devm_uchger_dev_match, uchger);
>> +}
>> +
>> +/*
>> + * usb_charger_register() - Register a new usb charger device.
>> + * @uchger - the new usb charger device.
>> + *
>> + */
>> +int usb_charger_register(struct device *dev, struct usb_charger *uchger)
>> +{
>> + static atomic_t uchger_no = ATOMIC_INIT(-1);
>> + struct usb_charger *tmp;
>> + int ret;
>> +
>> + if (!uchger) {
>> + dev_err(dev, "no device provided for charger\n");
>> + return -EINVAL;
>> + }
>> +
>> + uchger->dev.parent = dev;
>> + uchger->dev.release = usb_charger_release;
>> + dev_set_name(&uchger->dev, "usb-chger%lu",
>> + (unsigned long)atomic_inc_return(&uchger_no));
>
> For the name of usb-charger, which not using "usb-charger.x" directly?

OK.

>> +
>> + ret = device_register(&uchger->dev);
>> + if (ret) {
>> + put_device(&uchger->dev);
>> + return ret;
>> + }
>> +
>> + dev_set_drvdata(&uchger->dev, uchger);
>> +
>> + mutex_lock(&usb_charger_list_lock);
>> + list_for_each_entry(tmp, &usb_charger_list, entry) {
>> + if (!(strcmp(tmp->name, uchger->name))) {
>> + mutex_unlock(&usb_charger_list_lock);
>> + ret = -EEXIST;
>> + goto out;
>> + }
>> + }
>> + list_add_tail(&uchger->entry, &usb_charger_list);
>> + mutex_unlock(&usb_charger_list_lock);
>> +
>> + return 0;
>> +
>> +out:
>> + dev_err(dev, "Failed to register usb charger (%s)\n",
>> + uchger->name);
>> + device_unregister(&uchger->dev);
>> + put_device(&uchger->dev);
>> + return ret;
>> +}
>> +
>> +int devm_usb_charger_register(struct device *dev,
>> + struct usb_charger *uchger)
>> +{
>> + struct usb_charger **ptr;
>> + int ret;
>> +
>> + ptr = devres_alloc(devm_uchger_dev_unreg, sizeof(*ptr), GFP_KERNEL);
>> + if (!ptr)
>> + return -ENOMEM;
>> +
>> + ret = usb_charger_register(dev, uchger);
>> + if (ret) {
>> + devres_free(ptr);
>> + return ret;
>> + }
>> +
>> + *ptr = uchger;
>> + devres_add(dev, ptr);
>> +
>> + return 0;
>> +}
>> +
>> +int usb_charger_init(struct usb_gadget *ugadget)
>> +{
>> + struct usb_charger *uchger;
>> + struct extcon_dev *edev;
>> + char buf[100];
>> + char *str;
>> + int ret;
>> +
>> + if (!ugadget)
>> + return -EINVAL;
>> +
>> + uchger = devm_kzalloc(&ugadget->dev, sizeof(struct usb_charger),
>> + GFP_KERNEL);
>> + if (!uchger)
>> + return -ENOMEM;
>> +
>> + sprintf(buf, "usb-charger.%s", ugadget->name);
>> + str = devm_kzalloc(&ugadget->dev, sizeof(char) * (strlen(buf) + 1),
>> + GFP_KERNEL);
>> + if (!str)
>> + return -ENOMEM;
>> +
>> + strcpy(str, buf);
>> + uchger->name = str;
>> + uchger->type = UNKNOWN_TYPE;
>> + uchger->state = USB_CHARGER_DEFAULT;
>> + uchger->cur_limit.sdp_cur_limit = DEFAULT_SDP_CUR_LIMIT;
>> + uchger->cur_limit.dcp_cur_limit = DEFAULT_DCP_CUR_LIMIT;
>> + uchger->cur_limit.cdp_cur_limit = DEFAULT_CDP_CUR_LIMIT;
>> + uchger->cur_limit.aca_cur_limit = DEFAULT_ACA_CUR_LIMIT;
>> +
>> + atomic_set(&uchger->count, 1);
>> + spin_lock_init(&uchger->lock);
>> + INIT_LIST_HEAD(&uchger->entry);
>> + RAW_INIT_NOTIFIER_HEAD(&uchger->uchger_nh);
>> +
>> + /* register a notifier on a extcon device if it is exsited */
>> + edev = extcon_get_edev_by_phandle(ugadget->dev.parent, 0);
>> + if (!IS_ERR_OR_NULL(edev)) {
>> + uchger->extcon_dev = edev;
>> + uchger->extcon_nb.nb.notifier_call = usb_charger_plug_by_extcon;
>> + uchger->extcon_nb.uchger = uchger;
>> + usb_charger_register_extcon_notifier(uchger, edev, EXTCON_USB);
>> + }
>> +
>> + /* register a notifier on a usb gadget device */
>> + uchger->gadget = ugadget;
>> + ugadget->uchger = uchger;
>> + uchger->old_gadget_state = ugadget->state;
>> + uchger->gadget_nb.notifier_call = usb_charger_plug_by_gadget;
>> + usb_charger_register_gadget_notifier(uchger);
>> +
>> + ret = usb_charger_register(&ugadget->dev, uchger);
>> + if (ret)
>> + goto reg_fail;
>> +
>> + return 0;
>> +
>> +reg_fail:
>> + if (uchger->extcon_dev)
>> + usb_charger_unregister_extcon_notifier(uchger,
>> + uchger->extcon_dev, EXTCON_USB);
>> +
>> + usb_charger_unregister_gadget_notifier(uchger);
>> + return ret;
>> +}
>> +
>> +int usb_charger_exit(struct usb_gadget *ugadget)
>> +{
>> + struct usb_charger *uchger = ugadget->uchger;
>> +
>> + if (!uchger)
>> + return -EINVAL;
>> +
>> + if (uchger->extcon_dev)
>> + usb_charger_unregister_extcon_notifier(uchger,
>> + uchger->extcon_dev, EXTCON_USB);
>> +
>> + usb_charger_unregister_gadget_notifier(uchger);
>> + return usb_charger_unregister(uchger);
>> +}
>> +
>> +MODULE_AUTHOR("Baolin Wang <baolin.wang@xxxxxxxxxx>");
>> +MODULE_DESCRIPTION("USB charger driver");
>> diff --git a/include/linux/usb/usb_charger.h b/include/linux/usb/usb_charger.h
>> new file mode 100644
>> index 0000000..da4d3c9
>> --- /dev/null
>> +++ b/include/linux/usb/usb_charger.h
>> @@ -0,0 +1,101 @@
>> +#ifndef __LINUX_USB_CHARGER_H__
>> +#define __LINUX_USB_CHARGER_H__
>> +
>> +#include <linux/device.h>
>> +#include <linux/notifier.h>
>> +#include <linux/sysfs.h>
>> +#include <linux/usb/ch9.h>
>> +
>> +/* USB charger type:
>> + * SDP (Standard Downstream Port)
>> + * DCP (Dedicated Charging Port)
>> + * CDP (Charging Downstream Port)
>> + * ACA (Accessory Charger Adapters)
>> + */
>> +enum usb_charger_type {
>> + UNKNOWN_TYPE,
>> + SDP_TYPE,
>> + DCP_TYPE,
>> + CDP_TYPE,
>> + ACA_TYPE,
>> +};
>> +
>> +/* USB charger state */
>> +enum usb_charger_state {
>> + USB_CHARGER_DEFAULT,
>> + USB_CHARGER_PRESENT,
>> + USB_CHARGER_REMOVE,
>> +};
>> +
>> +/* Current limitation by charger type */
>> +struct usb_charger_cur_limit {
>> + unsigned int sdp_cur_limit;
>> + unsigned int dcp_cur_limit;
>> + unsigned int cdp_cur_limit;
>> + unsigned int aca_cur_limit;
>> +};
>> +
>> +struct usb_charger_nb {
>> + struct notifier_block nb;
>> + struct usb_charger *uchger;
>> +};
>> +
>> +struct usb_charger {
>> + /* Internal data. Please do not set. */
>> + const char *name;
>> + struct device dev;
>> + struct raw_notifier_head uchger_nh;
>> + struct list_head entry;
>> + spinlock_t lock;
>> + enum usb_charger_type type;
>> + enum usb_charger_state state;
>> + atomic_t count;
>> +
>> + /* For supporting extcon usb gpio */
>> + struct extcon_dev *extcon_dev;
>> + struct usb_charger_nb extcon_nb;
>> +
>> + /* For supporting usb gadget */
>> + struct usb_gadget *gadget;
>> + enum usb_device_state old_gadget_state;
>> + struct notifier_block gadget_nb;
>> +
>> + /* Current limitation */
>> + struct usb_charger_cur_limit cur_limit;
>> +};
>> +
>> +extern struct usb_charger *usb_charger_find_by_name(char *name);
>> +
>> +extern void usb_charger_register_notify(struct usb_charger *uchger,
>> + struct notifier_block *nb);
>> +extern void usb_charger_unregister_notify(struct usb_charger *uchger,
>> + struct notifier_block *nb);
>> +
>> +extern int usb_charger_register_extcon_notifier(struct usb_charger *uchger,
>> + struct extcon_dev *edev,
>> + unsigned int extcon_id);
>> +extern int usb_charger_unregister_extcon_notifier(struct usb_charger *uchger,
>> + struct extcon_dev *edev,
>> + unsigned int extcon_id);
>> +
>> +extern int usb_charger_register_gadget_notifier(struct usb_charger *uchger);
>> +extern int usb_charger_unregister_gadget_notifier(struct usb_charger *uchger);
>> +
>> +extern int usb_charger_set_cur_limit(struct usb_charger *uchger,
>> + struct usb_charger_cur_limit *cur_limit_set);
>> +extern enum usb_charger_type usb_charger_detect_type(struct usb_charger *uchger);
>> +
>> +extern int usb_charger_init(struct usb_gadget *ugadget);
>> +extern int usb_charger_exit(struct usb_gadget *ugadget);
>> +
>> +static inline void get_usb_charger(struct usb_charger *uchger)
>> +{
>> + atomic_inc(&uchger->count);
>> +}
>> +
>> +static inline void put_usb_charger(struct usb_charger *uchger)
>> +{
>> + atomic_dec(&uchger->count);
>> +}
>> +
>> +#endif /* __LINUX_USB_CHARGER_H__ */
>> --
>> 1.7.9.5
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-usb" in
>> the body of a message to majordomo@xxxxxxxxxxxxxxx
>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>
> --
>
> Best Regards,
> Peter Chen



--
Baolin.wang
Best Regards
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