Re: [PATCH 1/2] usb: cdns3: fix cdns3_core_init_role()

Roger Quadros
2019-10-16T09:21:07Z

Hi Pawel,

On 16/10/2019 07:32, Pawel Laszczak wrote:
> Hi Roger
>
>>
>> At startup we should trigger the HW state machine
>> only if it is OTG mode. Otherwise we should just
>> start the respective role.
>>
>> Initialize idle role by default. If we don't do this then
>> cdns3_idle_role_stop() is not called when switching to
>> host/device role and so lane switch mechanism
>> doesn't work. This results to super-speed device not working
>> in one orientation if it was plugged before driver probe.
>>
>> Signed-off-by: Roger Quadros <rogerq@ti.com>
>> Signed-off-by: Sekhar Nori <nsekhar@ti.com>
>> ---
>> drivers/usb/cdns3/core.c | 20 +++++++++++++++++++-
>> 1 file changed, 19 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/usb/cdns3/core.c b/drivers/usb/cdns3/core.c
>> index 06f1e105be4e..1109dc5a4c39 100644
>> --- a/drivers/usb/cdns3/core.c
>> +++ b/drivers/usb/cdns3/core.c
>> @@ -160,10 +160,28 @@ static int cdns3_core_init_role(struct cdns3 *cdns)
>> if (ret)
>> goto err;
>>
>> - if (cdns->dr_mode != USB_DR_MODE_OTG) {
>> + /* Initialize idle role to start with */
>> + ret = cdns3_role_start(cdns, USB_ROLE_NONE);
>> + if (ret)
>> + goto err;
>> +
>> + switch (cdns->dr_mode) {
>> + case USB_DR_MODE_UNKNOWN:
>
> One note in this place. USB_DR_MODE_UNKNOWN is not possible in this place.
> If cdns->dr_mode will be USB_DR_MODE_UNKNOWN then driver returns -EINVAL

At which place? I could not find.

> some line before after returning form cdns3_drd_update_mode and in consequence
> it jump to err label.
>
> Maybe for better readability it this condition should be treated here also as error.
>
>> + case USB_DR_MODE_OTG:
>> ret = cdns3_hw_role_switch(cdns);
>> if (ret)
>> goto err;
>> + break;
>> + case USB_DR_MODE_PERIPHERAL:
>> + ret = cdns3_role_start(cdns, USB_ROLE_DEVICE);
>> + if (ret)
>> + goto err;
>> + break;
>> + case USB_DR_MODE_HOST:
>> + ret = cdns3_role_start(cdns, USB_ROLE_HOST);
>> + if (ret)
>> + goto err;
>> + break;
>> }
>>
>> return ret;
>
> Reviewed-by: Pawel Laszczak <pawell@cadence.com>
> Tested-by: Pawel Laszczak <pawell@cadence.com>
>
> --
> Regards,
> Pawel
>

--
cheers,
-roger