Qualcomm Technologies, Inc. Standard Secure Digital Host Controller (SDHC)

Secure Digital Host Controller provides standard host interface to SD/MMC/SDIO cards.

Required properties:
  - compatible : should be "qcom,sdhci-msm"
		For SDCC version 5.0.0, MCI registers are removed from SDCC interface
		and some registers are moved to HC. New compatible string is added to
		support this change - "qcom,sdhci-msm-v5".
  - reg : should contain SDHC, SD Core register map.
  - reg-names : indicates various resources passed to driver (via reg proptery) by name.
		Required "reg-names" are "hc_mem" and "core_mem"
		optional ones are "tlmm_mem"
  - interrupts : should contain SDHC interrupts.
  - interrupt-names : indicates interrupts passed to driver (via interrupts property) by name.
		      Required "interrupt-names" are "hc_irq" and "pwr_irq".
  - <supply-name>-supply: phandle to the regulator device tree node
			  Required "supply-name" are "vdd" and "vdd-io".

Required alias:
- The slot number is specified via an alias with the following format
	'sdhc{n}' where n is the slot number.

Optional Properties:
	- interrupt-names - "status_irq". This status_irq will be used for card
			     detection.
	- qcom,bus-width - defines the bus I/O width that controller supports.
			   Units - number of bits. The valid bus-width values are
			   1, 4 and 8.
	- qcom,nonremovable - specifies whether the card in slot is
			      hot pluggable or hard wired.
	- qcom,nonhotplug - specifies the card in slot is not hot pluggable.
			    if card lost or removed manually at runtime, don't retry
			    to redetect it until next reboot probe.
	- qcom,bus-speed-mode - specifies supported bus speed modes by host.
				The supported bus speed modes are :
				"HS200_1p8v" - indicates that host can support HS200 at 1.8v.
				"HS200_1p2v" - indicates that host can support HS200 at 1.2v.
				"DDR_1p8v" - indicates that host can support DDR mode at 1.8v.
				"DDR_1p2v" - indicates that host can support DDR mode at 1.2v.
	- qcom,devfreq,freq-table - specifies supported frequencies for clock scaling.
				    Clock scaling logic shall toggle between these frequencies based
				    on card load. In case the defined frequencies are over or below
				    the supported card frequencies, they will be overridden
				    during card init. In case this entry is not supplied,
				    the driver will construct one based on the card
				    supported max and min frequencies.
				    The frequencies must be ordered from lowest to highest.
	- qcom,pm-qos-irq-type - the PM QoS request type to be used for IRQ voting.
	  Can be either "affine_cores" or "affine_irq". If not specified, will default
	  to "affine_cores". Use "affine_irq" setting in case an IRQ balancer is active,
	  and IRQ affinity changes during runtime.
	- qcom,pm-qos-irq-cpu - specifies the CPU for which IRQ voting shall be done.
	  If "affine_cores" was specified for property 'qcom,pm-qos-irq-type'
	  then this property must be defined, and is not relevant otherwise.
	- qcom,pm-qos-irq-latency - a tuple defining two latency values with which
	  PM QoS IRQ voting shall be done. The first value is the latecy to be used
	  when load is high (performance mode) and the second is for low loads
	  (power saving mode).
	- qcom,pm-qos-cpu-groups - defines cpu groups mapping.
	  Each cell represnets a group, which is a cpu bitmask defining which cpus belong
	  to that group.
	- qcom,pm-qos-<mode>-latency-us - where <mode> is either "cmdq" or "legacy".
	  An array of latency value tuples, each tuple corresponding to a cpu group in the order
	  defined in property 'qcom,pm-qos-cpu-groups'. The first value is the latecy to be used
	  when load is high (performance mode) and the second is for low loads
	  (power saving mode). These values will be used for cpu group voting for
	  command-queueing mode or legacy respectively.
	- qcom,core_3_0v_support: an optional property that is used to fake
	  3.0V support for SDIO devices.
	- qcom,scaling-lower-bus-speed-mode:	specifies the lower bus speed mode to be used
						during clock scaling. If this property is not
						defined, then it falls back to the default HS
						bus speed mode to maintain backward compatibility.

In the following, <supply> can be vdd (flash core voltage) or vdd-io (I/O voltage).
	- qcom,<supply>-always-on - specifies whether supply should be kept "on" always.
	- qcom,<supply>-lpm_sup - specifies whether supply can be kept in low power mode (lpm).
	- qcom,<supply>-voltage_level - specifies voltage levels for supply. Should be
					specified in pairs (min, max), units uV.
	- qcom,<supply>-current_level - specifies load levels for supply in lpm or
					high power mode (hpm). Should be specified in
					pairs (lpm, hpm), units uA.

	- gpios - specifies gpios assigned for sdhc slot.
	- qcom,gpio-names -  a list of strings that map in order to the list of gpios

	Tlmm pins are specified as <clk cmd data> and starting with eMMC5.0 as
	<clk cmd data rclk>

	- Refer to "Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt"
	  for following optional properties:
		- pinctrl-names
		- pinctrl-0, pinctrl-1,.. pinctrl-n

	- qcom,large-address-bus - specifies whether the soc is capable of
				 supporting larger than 32 bit address bus width.

	- qcom,wakeup-on-idle: if configured, the mmcqd thread will call
	  set_wake_up_idle(), thereby voting for it to be called on idle CPUs.

Example:

	aliases {
		sdhc1 = &sdhc_1;
	};

	sdhc_1: qcom,sdhc@f9824900 {
		compatible = "qcom,sdhci-msm";
                reg = <0xf9824900 0x11c>, <0xf9824000 0x800>;
                reg-names = "hc_mem", "core_mem";
                interrupts = <0 123 0>, <0 138 0>;
                interrupt-names = "hc_irq", "pwr_irq";

		vdd-supply = <&pm8941_l21>;
		vdd-io-supply = <&pm8941_l13>;
		qcom,vdd-voltage-level = <2950000 2950000>;
		qcom,vdd-current-level = <9000 800000>;

		qcom,vdd-io-always-on;
		qcom,vdd-io-lpm-sup;
		qcom,vdd-io-voltage-level = <1800000 2950000>;
		qcom,vdd-io-current-level = <6 22000>;

		qcom,devfreq,freq-table = <52000000 200000000>;

		pinctrl-names = "active", "sleep";
		pinctrl-0 = <&sdc1_clk_on &sdc1_cmd_on &sdc1_data_on>;
		pinctrl-1 = <&sdc1_clk_off &sdc1_cmd_on &sdc1_data_on>;


                qcom,bus-width = <4>;
		qcom,nonremovable;
		qcom,large-address-bus;
		qcom,bus-speed-mode = "HS200_1p8v", "DDR_1p8v";

		qcom,scaling-lower-bus-speed-mode = "DDR52";

		gpios = <&msmgpio 40 0>, /* CLK */
			<&msmgpio 39 0>, /* CMD */
			<&msmgpio 38 0>, /* DATA0 */
			<&msmgpio 37 0>, /* DATA1 */
			<&msmgpio 36 0>, /* DATA2 */
			<&msmgpio 35 0>; /* DATA3 */
		qcom,gpio-names = "CLK", "CMD", "DAT0", "DAT1", "DAT2", "DAT3";

		qcom,pm-qos-irq-type = "affine_cores";
		qcom,pm-qos-irq-cpu = <0>;
		qcom,pm-qos-irq-latency = <500 100>;
		qcom,pm-qos-cpu-groups = <0x03 0x0c>;
		qcom,pm-qos-cmdq-latency-us = <50 100>, <50 100>;
		qcom,pm-qos-legacy-latency-us = <50 100>, <50 100>;
	};

	sdhc_2: qcom,sdhc@f98a4900 {
		qcom,pm-qos-irq-type = "affine_irq";
		qcom,pm-qos-irq-latency = <120 200>;
	};