Re: [PATCH v2 1/3] mmc: pwrseq: add driver for emmc hardware reset

[Marek Szyprowski <m.szyprowski@samsung.com>]

Hello,

On 2015-02-02 09:59, Javier Martinez Canillas wrote:
> On Mon, Feb 2, 2015 at 9:33 AM, Marek Szyprowski
> <m.szyprowski@samsung.com> wrote:
>> +
>> +Required properties:
>> +- compatible : contains "mmc-pwrseq-emmc".
>> +- reset-gpios : contains a GPIO specifier. The reset GPIO is pulled
> The DT binding says that the "reset-gpios" is a required property...
>
>> +int mmc_pwrseq_emmc_alloc(struct mmc_host *host, struct device *dev)
>> +{
>> +       struct mmc_pwrseq_emmc *pwrseq;
>> +       int ret = 0;
>> +
>> +       pwrseq = kzalloc(sizeof(struct mmc_pwrseq_emmc), GFP_KERNEL);
>> +       if (!pwrseq)
>> +               return -ENOMEM;
>> +
>> +       pwrseq->reset_gpio = gpiod_get_index(dev, "reset", 0, GPIOD_OUT_LOW);
>> +       if (IS_ERR(pwrseq->reset_gpio) &&
>> +               PTR_ERR(pwrseq->reset_gpio) != -ENOENT &&
>> +               PTR_ERR(pwrseq->reset_gpio) != -ENOSYS) {
>> +               ret = PTR_ERR(pwrseq->reset_gpio);
>> +               goto free;
>> +       }
> ...but here the GPIO is made optional since this will return and
> propagate the error only for -EPROBE_DEFER error but won't do it for
> -ENOENT and -ENOSYS.

Thanks for spotting this. reset-gpios is required, this driver really 
makes no
sense without a gpio pin. I copied code from mmc-pwrseq-simple, which 
handled
optional gpio pins. I will fix this is a few minutes.

Best regards
-- 
Marek Szyprowski, PhD
Samsung R&D Institute Poland