1 * Exynos DWC_mobile_storage 2 3 The Exynos provides DWC_mobile_storage interface which supports 4 . Embedded Multimedia Cards (EMMC-version 4.5) 5 . Secure Digital memory (SD mem-version 2.0) 6 . Secure Digital I/O (SDIO-version 3.0) 7 . Consumer Electronics Advanced Transport Architecture (CE-ATA-version 1.1) 8 9 The Exynos DWC_mobile_storage provides four channels. 10 SOC specific and Board specific properties are channel specific. 11 12 Required SoC Specific Properties: 13 14 - compatible: should be 15 - samsung,exynos-dwmmc: for exynos platforms 16 17 - reg: physical base address of the controller and length of memory mapped 18 region. 19 20 - interrupts: The interrupt number to the cpu. 21 22 Required Board Specific Properties: 23 24 - #address-cells: should be 1. 25 - #size-cells: should be 0. 26 - samsung,bus-width: The width of the bus used to interface the devices 27 supported by DWC_mobile_storage (SD-MMC/EMMC/SDIO). 28 . Typically the bus width is 4 or 8. 29 - samsung,timing: The timing values to be written into the 30 Drv/sample clock selection register of corresponding channel. 31 . It is comprised of 3 values corresponding to the 3 fileds 32 'SelClk_sample', 'SelClk_drv' and 'DIVRATIO' of CLKSEL register. 33 . SelClk_sample: Select sample clock among 8 shifted clocks. 34 . SelClk_drv: Select drv clock among 8 shifted clocks. 35 . DIVRATIO: Clock Divide ratio select. 36 . The above 3 values are used by the clock phase shifter. 37 38 Example: 39 40 mmc@12200000 { 41 samsung,bus-width = <8>; 42 samsung,timing = <1 3 3>; 43 samsung,removable = <1>; 44 } 45 In the above example, 46 . The bus width is 8 47 . Timing is comprised of 3 values as explained below 48 1 - SelClk_sample 49 3 - SelClk_drv 50 3 - DIVRATIO 51 . The 'removable' flag indicates whether the the particilar device 52 cannot be removed (always present) or it is a removable device. 53 1 - Indicates that the device is removable. 54 0 - Indicates that the device cannot be removed. 55
