RE: [RFC PATCH v2 08/15] usb:cdns3: Implements device operations part of the API

From: Pawel Laszczak
Date: Mon Dec 03 2018 - 05:20:03 EST


Hi
>>> +
>>> +static struct usb_ep *cdns3_gadget_match_ep(struct usb_gadget *gadget,
>>> + struct usb_endpoint_descriptor *desc,
>>> + struct usb_ss_ep_comp_descriptor *comp_desc)
>>> +{
>>> + struct cdns3_device *priv_dev = gadget_to_cdns3_device(gadget);
>>> + struct cdns3_endpoint *priv_ep;
>>> + unsigned long flags;
>>> +
>>> + priv_ep = cdns3_find_available_ss_ep(priv_dev, desc);
>>> + if (IS_ERR(priv_ep)) {
>>> + dev_err(&priv_dev->dev, "no available ep\n");
>>> + return NULL;
>>> + }
>>> +
>>> + dev_dbg(&priv_dev->dev, "match endpoint: %s\n", priv_ep->name);
>>> +
>>> + spin_lock_irqsave(&priv_dev->lock, flags);
>>> + priv_ep->endpoint.desc = desc;
>>> + priv_ep->dir = usb_endpoint_dir_in(desc) ? USB_DIR_IN : USB_DIR_OUT;
>>> + priv_ep->type = usb_endpoint_type(desc);
>>> +
>>> + list_add_tail(&priv_ep->ep_match_pending_list,
>>> + &priv_dev->ep_match_list);
>>> + spin_unlock_irqrestore(&priv_dev->lock, flags);
>>> + return &priv_ep->endpoint;
>>> +}
>>
>>Why do you need a custom match_ep?
>>doesn't usb_ep_autoconfig suffice?
>
>I need to test it but at first glance it looks like usb_ep_autoconfig suffice.
>
>>
>>You can check if EP is claimed or not by checking the ep->claimed flag.
>>
I checked it and did not work correct. The flag claimed is set in usb_ep_autoconf, but
a little bit later during USB RESET this flag is cleared.
So, I can't base on this flag. I think that it's incorrect behavior in gadget core driver or in function drivers.
Maybe we should have additional flag in usb_ep object used during resetting, or usb_ep_autoconf function should be called after each USB RESET.

I notice that I can based on ep->address it is set also in usb_ep_autoconf and probably is not cleared anywhere.
It's little tricky, but It looks like it works correct. I add some comment for this checking.
Maybe in feature I will be able to replace it with claimed flag.

Felipe what's your opinion about claimed flag. It's should be fixed or not ?

Cheers
Pawel