Re: [PATCH] usb: gadget: udc: atmel: Also get regmap for at91sam9x5-pmc

[Uwe Kleine-König]

Hello,

On Mon, Jun 13, 2016 at 10:47:30AM +0200, Alexandre Belloni wrote:
> The "atmel,at91sam9g45-udc" compatible UDC is also used on at91sam9x5 so it
> is also necessary to try to get the syscon for at91sam9x5-pmc.
> 
> Fixes: 4747639f01c9 ("usb: gadget: atmel: access the PMC using regmap")
> Reported-by: Uwe Kleine-König <u.kleine-koenig@xxxxxxxxxxxxxx>

I played with the AT91 during my non-work time, so please use
uwe@xxxxxxxxxxxxxxxxx as my email address.

> Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxxxxxxxxx>
> ---
>  drivers/usb/gadget/udc/atmel_usba_udc.c | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/drivers/usb/gadget/udc/atmel_usba_udc.c b/drivers/usb/gadget/udc/atmel_usba_udc.c
> index 18569de06b04..bb1f6c8f0f01 100644
> --- a/drivers/usb/gadget/udc/atmel_usba_udc.c
> +++ b/drivers/usb/gadget/udc/atmel_usba_udc.c
> @@ -1920,6 +1920,8 @@ static struct usba_ep * atmel_udc_of_init(struct platform_device *pdev,
>  
>  	udc->errata = match->data;
>  	udc->pmc = syscon_regmap_lookup_by_compatible("atmel,at91sam9g45-pmc");
> +	if (IS_ERR(udc->pmc))
> +		udc->pmc = syscon_regmap_lookup_by_compatible("atmel,at91sam9x5-pmc");
>  	if (udc->errata && IS_ERR(udc->pmc))
>  		return ERR_CAST(udc->pmc);

I didn't retest but I'm sure this makes usb gadget work on my AT91.
Still I'm unsure if the patch is correct. Can

	syscon_regmap_lookup_by_compatible("atmel,at91sam9g45-pmc")

return -EPROBE_DEFER? Are there other error codes that should be fatal
enough to not try to look for a sam9x5-pmc?

Nearly orthogonal to the issue: An error message on failure would be
nice. When I saw usb gadget broken I first had to add messages to this
driver to see where it failed.

Best regards
Uwe

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Pengutronix e.K.                           | Uwe Kleine-König            |
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