Re: [PATCH v2 2/5] mmc: mediatek: Add Mediatek MMC driver

[Sascha Hauer <s.hauer@pengutronix.de>]

Ulf,

On Tue, Mar 31, 2015 at 02:23:06PM +0200, Ulf Hansson wrote:
> On 17 March 2015 at 04:13, Chaotian Jing <chaotian.jing@mediatek.com> wrote:
> > +
> > +       msdc_set_buswidth(host, ios->bus_width);
> > +
> > +       /* Suspend/Resume will do power off/on */
> > +       switch (ios->power_mode) {
> > +       case MMC_POWER_UP:
> > +               msdc_init_hw(host);
> > +               if (!IS_ERR(mmc->supply.vmmc)) {
> > +                       ret = mmc_regulator_set_ocr(mmc, mmc->supply.vmmc,
> > +                                       ios->vdd);
> > +                       if (ret) {
> > +                               dev_err(host->dev, "Failed to set vmmc power!\n");
> > +                               return;
> > +                       }
> > +               }
> > +               break;
> > +       case MMC_POWER_ON:
> > +               if (!IS_ERR(mmc->supply.vqmmc)) {
> > +                       ret = regulator_enable(mmc->supply.vqmmc);
> 
> The calls to regulator_enable|disable() for the vqmmc will not be
> balanced properly here. You need a local cache variable like
> "is_enabled" to keep track of this.

Shouldn't the MMC core provide balanced hooks for this? What about
MMC_POWER_UP, can this be used for enabling regulators?

Sascha

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