On Thu, 2018-01-11 at 09:57 +0200, Adrian Hunter wrote: > On 10/01/18 22:06, Ulf Hansson wrote: > > On 10 January 2018 at 19:04, Andy Shevchenko > > <andriy.shevchenko@xxxxxxxxxxxxxxx> wrote: > > > On Wed, 2018-01-10 at 18:01 +0100, Ulf Hansson wrote: > > > > On 10 January 2018 at 16:32, Andy Shevchenko > > > > <andriy.shevchenko@xxxxxxxxxxxxxxx> wrote: > > > > > On Intel Edison the Broadcom WiFi card, which is connected to > > > > > SDIO, > > > > > requires 2.0v, while the host, according to Intel Merrifield > > > > > TRM, > > > > > supports 1.8v supply only. > > > > > + /* > > > > > + * Without a regulator, SDHCI does not support 2.0v > > > > > but we > > > > > get > > > > > + * here because we advertised 2.0v support for > > > > > compatibility > > > > > + * with the SDIO card's OCR. Map it to 1.8v for the > > > > > purpose > > > > > of > > > > > + * turning on the power. > > > > > + */ > > > > > + if (IS_ERR(host->mmc->supply.vmmc) && vdd == > > > > > ilog2(MMC_VDD_20_21)) > > > > > + vdd = ilog2(MMC_VDD_165_195); > > > > > > > > Why not instead extend the range in sdhci_set_power_noreg() to > > > > also > > > > check for MMC_VDD_20_21? > > > > > > > > Or is there a problem with that? > > > > > > Do we have any grounds to do this in generic code? > > > > > > Moreover, if we check for 2.0v what should we do in generic code? > > > For my understanding > > > > > > case _20_21: > > > pwr = _180; > > > > Yeah, why is that a problem? > > Shouldn't be a problem. Just add a comment: > > /* > * Without a regulator, SDHCI does not support 2.0v so > we only > * get here if the driver deliberately added the 2.0v > range to > * ocr_avail. Map it to 1.8V for the purpose of turning > on the > * power. > */ > case MMC_VDD_20_21: > pwr = SDHCI_POWER_180; > break; OK. I will send v4 soon after giving some testing. > > What does other variants do in this regards? > > Use regulators or 3V I expect. Yep, correct. -- Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> Intel Finland Oy -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
