Re: [PATCH] mmc: pwrseq_simple: Make reset-gpios optional to match doc

Re: [PATCH] mmc: pwrseq_simple: Make reset-gpios optional to match doc

[Tony Lindgren]

Hi,

* Javier Martinez Canillas <javier@dowhile0.org> [160108 08:42]:
> On Fri, Jan 8, 2016 at 6:07 AM, Martin Fuzzey <mfuzzey@parkeon.com> wrote:
> > The DT binding doc says reset-gpios is an optional property but the code
> > currently bails out if it is omitted.
> >
> > Make the code match the documentation.
...
> Tony already posted a fix for this before [0] but got some feedback so
> is likely to post a v2 soon.

Hmm I think my patch would end up looking pretty much like Martin's
patch after fixing the comments. Based on what I understood, Ulf
wants to keep pwrseq_simple, well, simple as discussed in [0].

It also seems Ulf also wants to leave out the allocation, and does
want to add any deeper knowledge of the state of the GPIOs in
pwrse-simple. Instead, we can do device specific pwrseq for things
like Marvell 8787 and so on.

Ulf may have more comments, but $subject patch fixes the issue
I'm seeing with wl12xx on omap5 devices:

Tested-by: Tony Lindgren <tony@atomide.com>

Probably should be tagged Cc: stable # v4.4 when applied.

Regards,

Tony

> [0]: http://www.spinics.net/lists/linux-mmc/msg34398.html

Re: [PATCH] mmc: pwrseq_simple: Make reset-gpios optional to match doc

[Ulf Hansson]

+Tony, Javier, linux-omap

On 8 January 2016 at 10:07, Martin Fuzzey <mfuzzey@parkeon.com> wrote:
> The DT binding doc says reset-gpios is an optional property but the code
> currently bails out if it is omitted.
>
> Make the code match the documentation.

As Tony pointed out, this is actually a regression. Can you please
update the change-log according to that.

>
> Signed-off-by: Martin Fuzzey <mfuzzey@parkeon.com>

Please add a fixes tag:
Fixes: ce037275861e ("mmc: pwrseq_simple: use GPIO descriptors array API")

> ---
>  drivers/mmc/core/pwrseq_simple.c |   21 +++++++++++++--------
>  1 file changed, 13 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/mmc/core/pwrseq_simple.c b/drivers/mmc/core/pwrseq_simple.c
> index d10538b..4d2962b 100644
> --- a/drivers/mmc/core/pwrseq_simple.c
> +++ b/drivers/mmc/core/pwrseq_simple.c
> @@ -29,15 +29,18 @@ struct mmc_pwrseq_simple {
>  static void mmc_pwrseq_simple_set_gpios_value(struct mmc_pwrseq_simple *pwrseq,
>                                               int value)
>  {
> -       int i;
>         struct gpio_descs *reset_gpios = pwrseq->reset_gpios;
> -       int values[reset_gpios->ndescs];
>
> -       for (i = 0; i < reset_gpios->ndescs; i++)
> -               values[i] = value;
> +       if (!IS_ERR(reset_gpios)) {
> +               int i;
> +               int values[reset_gpios->ndescs];
>
> -       gpiod_set_array_value_cansleep(reset_gpios->ndescs, reset_gpios->desc,
> -                                      values);
> +               for (i = 0; i < reset_gpios->ndescs; i++)
> +                       values[i] = value;
> +
> +               gpiod_set_array_value_cansleep(
> +                       reset_gpios->ndescs, reset_gpios->desc, values);
> +       }
>  }
>
>  static void mmc_pwrseq_simple_pre_power_on(struct mmc_host *host)
> @@ -79,7 +82,8 @@ static void mmc_pwrseq_simple_free(struct mmc_host *host)
>         struct mmc_pwrseq_simple *pwrseq = container_of(host->pwrseq,
>                                         struct mmc_pwrseq_simple, pwrseq);
>
> -       gpiod_put_array(pwrseq->reset_gpios);
> +       if (!IS_ERR(pwrseq->reset_gpios))
> +               gpiod_put_array(pwrseq->reset_gpios);
>
>         if (!IS_ERR(pwrseq->ext_clk))
>                 clk_put(pwrseq->ext_clk);
> @@ -112,7 +116,8 @@ struct mmc_pwrseq *mmc_pwrseq_simple_alloc(struct mmc_host *host,
>         }
>
>         pwrseq->reset_gpios = gpiod_get_array(dev, "reset", GPIOD_OUT_HIGH);
> -       if (IS_ERR(pwrseq->reset_gpios)) {
> +       if (IS_ERR(pwrseq->reset_gpios) &&
> +           PTR_ERR(pwrseq->reset_gpios) != -ENOENT) {

You need to check also for != -ENOSYS, as otherwise when
CONFIG_GPIOLIB is unset we will treat that as an error.
This is also what the original code did.

>                 ret = PTR_ERR(pwrseq->reset_gpios);
>                 goto clk_put;
>         }
>

Kind regards
Uffe