[U-Boot] [RFC PATCH v2 3/6] dm: usb: Add UCLASS_USB_DEV_GENERIC shutdown

[Jagan Teki]

On Tue, Jul 24, 2018 at 5:18 AM, Simon Glass <sjg at chromium.org> wrote:
> Hi Jagan,
>
> On 20 July 2018 at 01:13, Jagan Teki <jagan at amarulasolutions.com> wrote:
>> Some OTG controllers which operates on Peripheral
>> mode are registered as UCLASS_USB_DEV_GENERIC.
>>
>> So add support to shutdown them as well. shutdown
>> happened during 'usb reset' and U-Boot handoff code
>> for Linux boot.
>>
>> controller restarting in 'usb reset' like probing
>> again is still missing for this type of UCLASS.
>>
>> Cc: Simon Glass <sjg at chromium.org>
>> Signed-off-by: Jagan Teki <jagan at amarulasolutions.com>
>> ---
>> Note:
>> I tried of traversing for multiple UCLASS in removal
>> code in usb_stop, but couldn't come with proper solutions.
>> I don't think any other area of code need a requirement like
>> this, or may be I'm missing. any help would appreciate.
>>
>> Changes for v2:
>> - none
>>
>>  drivers/usb/host/usb-uclass.c | 43 +++++++++++++++++++++++++++++++++++
>>  1 file changed, 43 insertions(+)
>>
>> diff --git a/drivers/usb/host/usb-uclass.c b/drivers/usb/host/usb-uclass.c
>> index 611ea97a72..99cf3d2b49 100644
>> --- a/drivers/usb/host/usb-uclass.c
>> +++ b/drivers/usb/host/usb-uclass.c
>> @@ -158,6 +158,45 @@ int usb_get_max_xfer_size(struct usb_device *udev, size_t *size)
>>         return ops->get_max_xfer_size(bus, size);
>>  }
>>
>> +int __usb_stop(void)
>
> Why the __ ? I think it should be something like usb_remove_and_unbind_all()
>
>> +{
>> +       struct udevice *bus;
>> +       struct udevice *rh;
>> +       struct uclass *uc;
>> +       struct usb_uclass_priv *uc_priv;
>> +       int err = 0, ret;
>> +
>> +       /* De-activate any devices that have been activated */
>> +       ret = uclass_get(UCLASS_USB_DEV_GENERIC, &uc);
>> +       if (ret)
>> +               return ret;
>> +
>> +       uc_priv = uc->priv;
>> +
>> +       uclass_foreach_dev(bus, uc) {
>> +               ret = device_remove(bus, DM_REMOVE_NORMAL);
>> +               if (ret && !err)
>> +                       err = ret;
>> +
>> +               /* Locate root hub device */
>> +               device_find_first_child(bus, &rh);
>> +               if (rh) {
>> +                       /*
>> +                        * All USB devices are children of root hub.
>> +                        * Unbinding root hub will unbind all of its children.
>> +                        */
>> +                       ret = device_unbind(rh);
>> +                       if (ret && !err)
>> +                               err = ret;
>> +               }
>> +       }
>> +
>> +       uc_priv->companion_device_count = 0;
>> +       usb_started = 0;
>> +
>> +       return err;
>> +}
>> +
>>  int usb_stop(void)
>>  {
>>         struct udevice *bus;
>> @@ -166,6 +205,10 @@ int usb_stop(void)
>>         struct usb_uclass_priv *uc_priv;
>>         int err = 0, ret;
>>
>> +       ret = __usb_stop();
>> +       if (ret)
>> +               return ret;
>> +
>
> This looks like the same code that appears below here, or very
> similar. Why is this needed?

Here the usage-case it to remove/unbind UCLASS_USB and
UCLASS_USB_DEV_GENERIC and same code will use to do that, any
suggestions?