1Rockchip SRAM for IO Voltage Domains: 2------------------------------------- 3 4IO domain voltages on some Rockchip SoCs are variable but need to be 5kept in sync between the regulators and the SoC using a special 6register. 7 8A specific example using rk3288: 9- If the regulator hooked up to a pin like SDMMC0_VDD is 3.3V then 10 bit 7 of GRF_IO_VSEL needs to be 0. If the regulator hooked up to 11 that same pin is 1.8V then bit 7 of GRF_IO_VSEL needs to be 1. 12 13Said another way, this driver simply handles keeping bits in the SoC's 14general register file (GRF) in sync with the actual value of a voltage 15hooked up to the pins. 16 17Note that this driver specifically doesn't include: 18- any logic for deciding what voltage we should set regulators to 19- any logic for deciding whether regulators (or internal SoC blocks) 20 should have power or not have power 21 22If there were some other software that had the smarts of making 23decisions about regulators, it would work in conjunction with this 24driver. When that other software adjusted a regulator's voltage then 25this driver would handle telling the SoC about it. A good example is 26vqmmc for SD. In that case the dw_mmc driver simply is told about a 27regulator. It changes the regulator between 3.3V and 1.8V at the 28right time. This driver notices the change and makes sure that the 29SoC is on the same page. 30 31 32Required properties: 33- compatible: should be one of: 34 - "rockchip,px30-io-voltage-domain" for px30 35 - "rockchip,px30-pmu-io-voltage-domain" for px30 pmu-domains 36 - "rockchip,rk3188-io-voltage-domain" for rk3188 37 - "rockchip,rk3228-io-voltage-domain" for rk3228 38 - "rockchip,rk3288-io-voltage-domain" for rk3288 39 - "rockchip,rk3328-io-voltage-domain" for rk3328 40 - "rockchip,rk3368-io-voltage-domain" for rk3368 41 - "rockchip,rk3368-pmu-io-voltage-domain" for rk3368 pmu-domains 42 - "rockchip,rk3399-io-voltage-domain" for rk3399 43 - "rockchip,rk3399-pmu-io-voltage-domain" for rk3399 pmu-domains 44 - "rockchip,rv1108-io-voltage-domain" for rv1108 45 - "rockchip,rv1108-pmu-io-voltage-domain" for rv1108 pmu-domains 46 47Deprecated properties: 48- rockchip,grf: phandle to the syscon managing the "general register files" 49 Systems should move the io-domains to a sub-node of the grf simple-mfd. 50 51You specify supplies using the standard regulator bindings by including 52a phandle the relevant regulator. All specified supplies must be able 53to report their voltage. The IO Voltage Domain for any non-specified 54supplies will be not be touched. 55 56Possible supplies for PX30: 57- vccio6-supply: The supply connected to VCCIO6. 58- vccio1-supply: The supply connected to VCCIO1. 59- vccio2-supply: The supply connected to VCCIO2. 60- vccio3-supply: The supply connected to VCCIO3. 61- vccio4-supply: The supply connected to VCCIO4. 62- vccio5-supply: The supply connected to VCCIO5. 63- vccio-oscgpi-supply: The supply connected to VCCIO_OSCGPI. 64 65Possible supplies for PX30 pmu-domains: 66- pmuio1-supply: The supply connected to PMUIO1. 67- pmuio2-supply: The supply connected to PMUIO2. 68 69Possible supplies for rk3188: 70- ap0-supply: The supply connected to AP0_VCC. 71- ap1-supply: The supply connected to AP1_VCC. 72- cif-supply: The supply connected to CIF_VCC. 73- flash-supply: The supply connected to FLASH_VCC. 74- lcdc0-supply: The supply connected to LCD0_VCC. 75- lcdc1-supply: The supply connected to LCD1_VCC. 76- vccio0-supply: The supply connected to VCCIO0. 77- vccio1-supply: The supply connected to VCCIO1. 78 Sometimes also labeled VCCIO1 and VCCIO2. 79 80Possible supplies for rk3228: 81- vccio1-supply: The supply connected to VCCIO1. 82- vccio2-supply: The supply connected to VCCIO2. 83- vccio3-supply: The supply connected to VCCIO3. 84- vccio4-supply: The supply connected to VCCIO4. 85 86Possible supplies for rk3288: 87- audio-supply: The supply connected to APIO4_VDD. 88- bb-supply: The supply connected to APIO5_VDD. 89- dvp-supply: The supply connected to DVPIO_VDD. 90- flash0-supply: The supply connected to FLASH0_VDD. Typically for eMMC 91- flash1-supply: The supply connected to FLASH1_VDD. Also known as SDIO1. 92- gpio30-supply: The supply connected to APIO1_VDD. 93- gpio1830 The supply connected to APIO2_VDD. 94- lcdc-supply: The supply connected to LCDC_VDD. 95- sdcard-supply: The supply connected to SDMMC0_VDD. 96- wifi-supply: The supply connected to APIO3_VDD. Also known as SDIO0. 97 98Possible supplies for rk3368: 99- audio-supply: The supply connected to APIO3_VDD. 100- dvp-supply: The supply connected to DVPIO_VDD. 101- flash0-supply: The supply connected to FLASH0_VDD. Typically for eMMC 102- gpio30-supply: The supply connected to APIO1_VDD. 103- gpio1830 The supply connected to APIO4_VDD. 104- sdcard-supply: The supply connected to SDMMC0_VDD. 105- wifi-supply: The supply connected to APIO2_VDD. Also known as SDIO0. 106 107Possible supplies for rk3368 pmu-domains: 108- pmu-supply: The supply connected to PMUIO_VDD. 109- vop-supply: The supply connected to LCDC_VDD. 110 111Possible supplies for rk3399: 112- bt656-supply: The supply connected to APIO2_VDD. 113- audio-supply: The supply connected to APIO5_VDD. 114- sdmmc-supply: The supply connected to SDMMC0_VDD. 115- gpio1830 The supply connected to APIO4_VDD. 116 117Possible supplies for rk3399 pmu-domains: 118- pmu1830-supply:The supply connected to PMUIO2_VDD. 119 120Example: 121 122 io-domains { 123 compatible = "rockchip,rk3288-io-voltage-domain"; 124 rockchip,grf = <&grf>; 125 126 audio-supply = <&vcc18_codec>; 127 bb-supply = <&vcc33_io>; 128 dvp-supply = <&vcc_18>; 129 flash0-supply = <&vcc18_flashio>; 130 gpio1830-supply = <&vcc33_io>; 131 gpio30-supply = <&vcc33_pmuio>; 132 lcdc-supply = <&vcc33_lcd>; 133 sdcard-supply = <&vccio_sd>; 134 wifi-supply = <&vcc18_wl>; 135 }; 136