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

Pawel Laszczak
2019-10-16T04:32:45Z

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
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>

>--
>Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
>Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
--
Regards,
Pawel