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+* Exynos 5250 DWC_mobile_storage
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+
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+The Exynos 5250 provides DWC_mobile_storage interface which supports
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+. Embedded Multimedia Cards (EMMC-version 4.5)
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+. Secure Digital memory (SD mem-version 2.0)
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+. Secure Digital I/O (SDIO-version 3.0)
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+. Consumer Electronics Advanced Transport Architecture (CE-ATA-version 1.1)
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+
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+The Exynos 5250 DWC_mobile_storage provides four channels.
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+SOC specific and Board specific properties are channel specific.
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+
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+Required SoC Specific Properties:
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+
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+- compatible: should be
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+ - samsung,exynos5250-dwmmc: for exynos5250 platforms
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+
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+- reg: physical base address of the controller and length of memory mapped
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+ region.
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+
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+- interrupts: The interrupt number to the cpu.
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+
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+Required Board Specific Properties:
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+
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+- #address-cells: should be 1.
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+- #size-cells: should be 0.
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+- samsung,bus-width: The width of the bus used to interface the devices
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+ supported by DWC_mobile_storage (SD-MMC/EMMC/SDIO).
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+ . Typically the bus width is 4 or 8.
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+- samsung,timing: The timing values to be written into the
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+ Drv/sample clock selection register of corresponding channel.
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+ . It is comprised of 3 values corresponding to the 3 fileds
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+ 'SelClk_sample', 'SelClk_drv' and 'DIVRATIO' of CLKSEL register.
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+ . SelClk_sample: Select sample clock among 8 shifted clocks.
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+ . SelClk_drv: Select drv clock among 8 shifted clocks.
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+ . DIVRATIO: Clock Divide ratio select.
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+ . The above 3 values are used by the clock phase shifter.
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+
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+Example:
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+
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+mmc@12200000 {
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+ samsung,bus-width = <8>;
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+ samsung,timing = <1 3 3>;
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+ samsung,removable = <1>;
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+}
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+In the above example,
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+ . The bus width is 8
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+ . Timing is comprised of 3 values as explained below
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+ 1 - SelClk_sample
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+ 3 - SelClk_drv
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+ 3 - DIVRATIO
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+ . The 'removable' flag indicates whether the the particilar device
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+ cannot be removed (always present) or it is a removable device.
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+ 1 - Indicates that the device is removable.
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+ 0 - Indicates that the device cannot be removed.
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