Documentation/devicetree/bindings/mfd/max8998.txt

   1 * Maxim MAX8998, National/TI LP3974 multi-function device
   2
   3 The Maxim MAX8998 is a multi-function device which includes voltage/current
   4 regulators, real time clock, battery charging controller and several
   5 other sub-blocks. It is interfaced using an I2C interface. Each sub-block
   6 is addressed by the host system using different i2c slave address.
   7
   8 PMIC sub-block
   9 --------------
  10
  11 The PMIC sub-block contains a number of voltage and current regulators,
  12 with controllable parameters and dynamic voltage scaling capability.
  13 In addition, it includes a real time clock and battery charging controller
  14 as well. It is accessible at I2C address 0x66.
  15
  16 Required properties:
  17 - compatible: Should be one of the following:
  18     - "maxim,max8998" for Maxim MAX8998
  19     - "national,lp3974" or "ti,lp3974" for National/TI LP3974.
  20 - reg: Specifies the i2c slave address of the pmic block. It should be 0x66.
  21
  22 Optional properties:
  23 - interrupts: Interrupt specifiers for two interrupt sources.
  24   - First interrupt specifier is for main interrupt.
  25   - Second interrupt specifier is for power-on/-off interrupt.
  26 - max8998,pmic-buck1-dvs-gpios: GPIO specifiers for two host gpios used
  27   for buck 1 dvs. The format of the gpio specifier depends on the gpio
  28   controller.
  29 - max8998,pmic-buck2-dvs-gpio: GPIO specifier for host gpio used
  30   for buck 2 dvs. The format of the gpio specifier depends on the gpio
  31   controller.
  32 - max8998,pmic-buck1-default-dvs-idx: Default voltage setting selected from
  33   the possible 4 options selectable by the dvs gpios. The value of this
  34   property should be 0, 1, 2 or 3. If not specified or out of range,
  35   a default value of 0 is taken.
  36 - max8998,pmic-buck2-default-dvs-idx: Default voltage setting selected from
  37   the possible 2 options selectable by the dvs gpios. The value of this
  38   property should be 0 or 1. If not specified or out of range, a default
  39   value of 0 is taken.
  40 - max8998,pmic-buck-voltage-lock: If present, disallows changing of
  41   preprogrammed buck dvfs voltages.
  42
  43 Additional properties required if max8998,pmic-buck1-dvs-gpios is defined:
  44 - max8998,pmic-buck1-dvs-voltage: An array of 4 voltage values in microvolts
  45   for buck1 regulator that can be selected using dvs gpio.
  46
  47 Additional properties required if max8998,pmic-buck2-dvs-gpio is defined:
  48 - max8998,pmic-buck2-dvs-voltage: An array of 2 voltage values in microvolts
  49   for buck2 regulator that can be selected using dvs gpio.
  50
  51 Regulators: All the regulators of MAX8998 to be instantiated shall be
  52 listed in a child node named 'regulators'. Each regulator is represented
  53 by a child node of the 'regulators' node.
  54
  55         regulator-name {
  56                 /* standard regulator bindings here */
  57         };
  58
  59 Following regulators of the MAX8998 PMIC block are supported. Note that
  60 the 'n' in regulator name, as in LDOn or BUCKn, represents the LDO or BUCK
  61 number as described in MAX8998 datasheet.
  62
  63         - LDOn
  64                   - valid values for n are 2 to 17
  65                   - Example: LDO2, LDO10, LDO17
  66         - BUCKn
  67                   - valid values for n are 1 to 4.
  68                   - Example: BUCK1, BUCK2, BUCK3, BUCK4
  69
  70         - ENVICHG: Battery Charging Current Monitor Output. This is a fixed
  71                    voltage type regulator
  72
  73         - ESAFEOUT1: (ldo19)
  74         - ESAFEOUT2: (ld020)
  75
  76 Standard regulator bindings are used inside regulator subnodes. Check
  77   Documentation/devicetree/bindings/regulator/regulator.txt
  78 for more details.
  79
  80 Example:
  81
  82         pmic@66 {
  83                 compatible = "maxim,max8998-pmic";
  84                 reg = <0x66>;
  85                 interrupt-parent = <&wakeup_eint>;
  86                 interrupts = <4 0>, <3 0>;
  87
  88                 /* Buck 1 DVS settings */
  89                 max8998,pmic-buck1-default-dvs-idx = <0>;
  90                 max8998,pmic-buck1-dvs-gpios = <&gpx0 0 1 0 0>, /* SET1 */
  91                                                <&gpx0 1 1 0 0>; /* SET2 */
  92                 max8998,pmic-buck1-dvs-voltage = <1350000>, <1300000>,
  93                                                  <1000000>, <950000>;
  94
  95                 /* Buck 2 DVS settings */
  96                 max8998,pmic-buck2-default-dvs-idx = <0>;
  97                 max8998,pmic-buck2-dvs-gpio = <&gpx0 0 3 0 0>; /* SET3 */
  98                 max8998,pmic-buck2-dvs-voltage = <1350000>, <1300000>;
  99
 100                 /* Regulators to instantiate */
 101                 regulators {
 102                         ldo2_reg: LDO2 {
 103                                 regulator-name = "VDD_ALIVE_1.1V";
 104                                 regulator-min-microvolt = <1100000>;
 105                                 regulator-max-microvolt = <1100000>;
 106                                 regulator-always-on;
 107                         };
 108
 109                         buck1_reg: BUCK1 {
 110                                 regulator-name = "VDD_ARM_1.2V";
 111                                 regulator-min-microvolt = <950000>;
 112                                 regulator-max-microvolt = <1350000>;
 113                                 regulator-always-on;
 114                                 regulator-boot-on;
 115                         };
 116                 };
 117         };