[PATCH V2] mmc: core: try 1.8v signaling in ddr mode if host and device

2014-08-14 Thread Chuanxiao Dong
Even (e)MMC card can support 3.3v to 1.2v vccq in DDR, but not all host controller can support this, like some of the SDHCI host which connect to an eMMC device. Some of these host controller still needs to use 1.8v vccq for supporting DDR mode. So the sequence will be: if (host and device can

Re: [PATCH V2] mmc: core: try 1.8v signaling in ddr mode if host and device

2014-08-14 Thread Ulf Hansson
On 14 August 2014 11:54, Chuanxiao Dong chuanxiao.d...@intel.com wrote: Even (e)MMC card can support 3.3v to 1.2v vccq in DDR, but not all host controller can support this, like some of the SDHCI host which connect to an eMMC device. Some of these host controller still needs to use 1.8v vccq