Re: [PATCH v2 1/3] gadget: Support for the usb charger framework

[Baolin Wang]

On 17 August 2015 at 08:40, Peter Chen <peter.chen@xxxxxxxxxxxxx> wrote:
> On Fri, Aug 14, 2015 at 05:47:44PM +0800, Baolin Wang wrote:
>> The usb charger framework is based on usb gadget, and each usb gadget
>> can be one usb charger to set the current limitation.
>>
>> This patch adds a notifier mechanism for usb charger to report to usb
>> charger when the usb gadget state is changed.
>>
>> Also we introduce a callback 'get_charger_type' which will implemented
>> by user for usb gadget operations to get the usb charger type.
>>
>> Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxx>
>> ---
>>  drivers/usb/gadget/udc/udc-core.c |   38 +++++++++++++++++++++++++++++++++++++
>>  include/linux/usb/gadget.h        |   20 +++++++++++++++++++
>>  2 files changed, 58 insertions(+)
>>
>> diff --git a/drivers/usb/gadget/udc/udc-core.c b/drivers/usb/gadget/udc/udc-core.c
>> index f660afb..47b231c 100644
>> --- a/drivers/usb/gadget/udc/udc-core.c
>> +++ b/drivers/usb/gadget/udc/udc-core.c
>> @@ -28,6 +28,7 @@
>>  #include <linux/usb/ch9.h>
>>  #include <linux/usb/gadget.h>
>>  #include <linux/usb.h>
>> +#include <linux/usb/usb_charger.h>
>>
>>  /**
>>   * struct usb_udc - describes one usb device controller
>> @@ -129,6 +130,32 @@ void usb_gadget_giveback_request(struct usb_ep *ep,
>>  }
>>  EXPORT_SYMBOL_GPL(usb_gadget_giveback_request);
>>
>> +int usb_gadget_register_notify(struct usb_gadget *gadget,
>> +                            struct notifier_block *nb)
>> +{
>> +     int ret;
>> +
>> +     mutex_lock(&gadget->lock);
>> +     ret = raw_notifier_chain_register(&gadget->nh, nb);
>> +     mutex_unlock(&gadget->lock);
>> +
>> +     return ret;
>> +}
>> +EXPORT_SYMBOL_GPL(usb_gadget_register_notify);
>> +
>> +int usb_gadget_unregister_notify(struct usb_gadget *gadget,
>> +                              struct notifier_block *nb)
>> +{
>> +     int ret;
>> +
>> +     mutex_lock(&gadget->lock);
>> +     ret = raw_notifier_chain_unregister(&gadget->nh, nb);
>> +     mutex_unlock(&gadget->lock);
>> +
>> +     return ret;
>> +}
>> +EXPORT_SYMBOL_GPL(usb_gadget_unregister_notify);
>> +
>>  /* ------------------------------------------------------------------------- */
>>
>>  /**
>> @@ -226,6 +253,10 @@ static void usb_gadget_state_work(struct work_struct *work)
>>       struct usb_gadget *gadget = work_to_gadget(work);
>>       struct usb_udc *udc = gadget->udc;
>>
>> +     mutex_lock(&gadget->lock);
>> +     raw_notifier_call_chain(&gadget->nh, gadget->state, gadget);
>> +     mutex_unlock(&gadget->lock);
>> +
>>       if (udc)
>>               sysfs_notify(&udc->dev.kobj, NULL, "state");
>>  }
>> @@ -364,6 +395,8 @@ int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget,
>>
>>       dev_set_name(&gadget->dev, "gadget");
>>       INIT_WORK(&gadget->work, usb_gadget_state_work);
>> +     RAW_INIT_NOTIFIER_HEAD(&gadget->nh);
>> +     mutex_init(&gadget->lock);
>>       gadget->dev.parent = parent;
>>
>>  #ifdef       CONFIG_HAS_DMA
>> @@ -405,6 +438,10 @@ int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget,
>>
>>       mutex_unlock(&udc_lock);
>>
>> +     ret = usb_charger_init(gadget);
>> +     if (ret)
>> +             goto err4;
>> +
>
> If the charger's initialization fails, you may need to
> call device_del(&udc->dev).
>

Yes, I missed that. Thanks for your comments.

> Peter
>
>>       return 0;
>>
>>  err4:
>> @@ -481,6 +518,7 @@ void usb_del_gadget_udc(struct usb_gadget *gadget)
>>       kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE);
>>       flush_work(&gadget->work);
>>       device_unregister(&udc->dev);
>> +     usb_charger_exit(gadget);
>>       device_unregister(&gadget->dev);
>>  }
>>  EXPORT_SYMBOL_GPL(usb_del_gadget_udc);
>> diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h
>> index c14a69b..78cc862 100644
>> --- a/include/linux/usb/gadget.h
>> +++ b/include/linux/usb/gadget.h
>> @@ -537,6 +537,7 @@ struct usb_gadget_ops {
>>       struct usb_ep *(*match_ep)(struct usb_gadget *,
>>                       struct usb_endpoint_descriptor *,
>>                       struct usb_ss_ep_comp_descriptor *);
>> +     enum usb_charger_type   (*get_charger_type)(struct usb_gadget *);
>>  };
>>
>>  /**
>> @@ -609,6 +610,9 @@ struct usb_gadget {
>>       unsigned                        out_epnum;
>>       unsigned                        in_epnum;
>>       struct usb_otg_caps             *otg_caps;
>> +     struct raw_notifier_head        nh;
>> +     struct usb_charger              *uchger;
>> +     struct mutex                    lock;
>>
>>       unsigned                        sg_supported:1;
>>       unsigned                        is_otg:1;
>> @@ -1183,6 +1187,22 @@ extern void usb_gadget_unmap_request(struct usb_gadget *gadget,
>>
>>  /*-------------------------------------------------------------------------*/
>>
>> +/**
>> + * Register a notifiee to get notified by any attach status changes from
>> + * the usb gadget
>> + */
>> +int usb_gadget_register_notify(struct usb_gadget *gadget,
>> +                            struct notifier_block *nb);
>> +
>> +/*-------------------------------------------------------------------------*/
>> +
>> +
>> +/* Unregister a notifiee from the usb gadget */
>> +int usb_gadget_unregister_notify(struct usb_gadget *gadget,
>> +                              struct notifier_block *nb);
>> +
>> +/*-------------------------------------------------------------------------*/
>> +
>>  /* utility to set gadget state properly */
>>
>>  extern void usb_gadget_set_state(struct usb_gadget *gadget,
>> --
>> 1.7.9.5
>>
>
> --
>
> Best Regards,
> Peter Chen



-- 
Baolin.wang
Best Regards
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