[PATCH] AT91 USB Serial Device

[Rob Emanuele]

Hi Nicolas,

I came across a small bug while debugging my problems of getting the
host interface and device interface to work at the same time but on
different ports.  I had compiled the atmel usb device support as a
module and after unloading it and trying to reload it, the irq for
vbus was not released.  This little patch fixes that

diff --git a/drivers/usb/gadget/atmel_usba_udc.c
b/drivers/usb/gadget/atmel_usba_udc.c
index d6ef3d5..bc70e53 100644
--- a/drivers/usb/gadget/atmel_usba_udc.c
+++ b/drivers/usb/gadget/atmel_usba_udc.c
@@ -2052,8 +2052,10 @@ static int __exit usba_udc_remove(struct
platform_device *pdev)
                usba_ep_cleanup_debugfs(&usba_ep[i]);
        usba_cleanup_debugfs(udc);

-       if (gpio_is_valid(udc->vbus_pin))
+       if (gpio_is_valid(udc->vbus_pin)) {
+               free_irq(gpio_to_irq(udc->vbus_pin), udc);
                gpio_free(udc->vbus_pin);
+       }

        free_irq(udc->irq, udc);
        kfree(usba_ep);


On Tue, Nov 9, 2010 at 3:59 PM, Rob Emanuele <poorarm at shoreis.com> wrote:
> Nicolas et al,
>
> Thank you for the information.  For the moment I have a boot option to
> use either 2 host ports or a host and a device port.  That would seem
> to fit my needs except for the case that I'm loading the usb serial
> gadget as a module and then specifying in the inittab that getty use
> it as ttyGS0.  In that case connecting the device port to a host does
> not seem to ever register on the host.  If I remove the getty line
> from inittab and then run getty manually after it boots, it works
> fine.  To add insult to injury, then it will work after reboot also
> until a hard power down.
>
> Anyone experience this?
>
> Thank you,
>
> Rob
>
> On Tue, Nov 9, 2010 at 9:46 AM, Nicolas Ferre <nicolas.ferre at atmel.com> wrote:
>> Le 05/11/2010 22:09, Rob Emanuele :
>>> Greetings,
>>>
>>> We've been developing a at91sam9g45 product and it is finally available at:
>>> https://www.crystalfontz.com/product/CFA910.html
>>
>> Very nice platform!
>>
>>> We are looking into supporting USB OTG on this device as the 'g45 has
>>> the USB host/device port.  As far at I can tell Atmel or anyone else
>>> working on this platform has not made full use of this as an OTG
>>> device.
>>
>> Indeed, it is not done for the moment...
>>
>>>  I haven't found support in the USB or the OTG code for
>>> reading the USB ID line to determine host or device mode.
>>
>> I am not sure USB ID is well supported by consumer cable providers and
>> is a reliable way to determine host or device mode.
>>
>>> Am I missing something or is that an area that needs some code written for it?
>>
>> Anyway, using this port as host or device is a matter of
>> 1/ driving or not VBUS pin
>> 2/ dealing with loading the gadget driver (as the "Enable" of the usba
>> IP is responsible for swithing to device mode).
>>
>> I think that determining if the port shall be used in host or device
>> mode can be asked through the GUI... But note that I am not an USB expert...
>> --
>> Nicolas Ferre
>>
>>
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>