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</o:shapelayout></xml><![endif]--></head><body lang=EN-IN link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span lang=EN-US>Hi,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Tegra sdhci platform driver currently enables the necessary gpios which will power on the SD host and sd/emmc cards. I have made changes to use vmmc and vqmmc regulators for the same.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>During testing on some platforms, I observed that the there is a possibility of regulator driver probe being deferred due to dependencies on other modules like gpio etc. In such case, the vmmc and vqmmc regulators will not be available. MMC/SD cards will not work without enabling the regulators. To fix this, I am deferring sdhci probe if regulator_get() calls fail. The probe will continue when the regulators are present. With this change, mmc and SD cards are working properly.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>However, this patch would require vmmc, vqmmc supplies to be registered either with a valid entry or a using dummy regulator entry for all platforms that use sdhci driver. I am aware of tegra platforms details and can add entries for the same. I don’t know the details of other platforms which are using sdhci driver. I can try adding regulator_get() calls in the sdhci tegra platform driver and bypass the regulator_get calls in sdhci driver if the regulator structures are already present. This wouldn’t effect non-tegra platforms. But, this is more of a hack and not a proper solution. I need suggestions on how to fix the issue properly without affecting other platforms. I have pushed patches with the above mentioned changes. I hope it helps in understanding better on what I am trying to do.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Regards,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Pavan.<o:p></o:p></span></p></div></body></html>