1 .. SPDX-License-Identifier: GPL-2.0-only 2 3 ============= 4 AD4000 driver 5 ============= 6 7 Device driver for Analog Devices Inc. AD4000 series of ADCs. 8 9 Supported devices 10 ================= 11 12 * `AD4000 <https://www.analog.com/AD4000>`_ 13 * `AD4001 <https://www.analog.com/AD4001>`_ 14 * `AD4002 <https://www.analog.com/AD4002>`_ 15 * `AD4003 <https://www.analog.com/AD4003>`_ 16 * `AD4004 <https://www.analog.com/AD4004>`_ 17 * `AD4005 <https://www.analog.com/AD4005>`_ 18 * `AD4006 <https://www.analog.com/AD4006>`_ 19 * `AD4007 <https://www.analog.com/AD4007>`_ 20 * `AD4008 <https://www.analog.com/AD4008>`_ 21 * `AD4010 <https://www.analog.com/AD4010>`_ 22 * `AD4011 <https://www.analog.com/AD4011>`_ 23 * `AD4020 <https://www.analog.com/AD4020>`_ 24 * `AD4021 <https://www.analog.com/AD4021>`_ 25 * `AD4022 <https://www.analog.com/AD4022>`_ 26 * `ADAQ4001 <https://www.analog.com/ADAQ4001>`_ 27 * `ADAQ4003 <https://www.analog.com/ADAQ4003>`_ 28 29 Wiring connections 30 ------------------ 31 32 Devices of the AD4000 series can be connected to the SPI host controller in a 33 few different modes. 34 35 CS mode, 3-wire turbo mode 36 ^^^^^^^^^^^^^^^^^^^^^^^^^^ 37 38 Datasheet "3-wire" mode is what most resembles standard SPI connection which, 39 for these devices, comprises of connecting the controller CS line to device CNV 40 pin and other SPI lines as usual. This configuration is (misleadingly) called 41 "CS Mode, 3-Wire Turbo Mode" connection in datasheets. 42 NOTE: The datasheet definition of 3-wire mode for the AD4000 series is NOT the 43 same of standard spi-3wire mode. 44 This is the only connection mode that allows configuration register access but 45 it requires the SPI controller to support the ``SPI_MOSI_IDLE_HIGH`` feature. 46 47 Omit the ``adi,sdi-pin`` property in device tree to select this mode. 48 49 :: 50 51 +-------------+ 52 + ----------------------------------| SDO | 53 | | | 54 | +-------------------| CS | 55 | v | | 56 | +--------------------+ | HOST | 57 | | CNV | | | 58 +--->| SDI AD4000 SDO |-------->| SDI | 59 | SCK | | | 60 +--------------------+ | | 61 ^ | | 62 +--------------------| SCLK | 63 +-------------+ 64 65 CS mode, 3-wire, without busy indicator 66 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 67 68 Another wiring configuration supported as "3-wire" mode has the SDI pin 69 hard-wired to digital input/output interface supply (VIO). In this setup, the 70 controller is not required to support ``SPI_MOSI_IDLE_HIGH`` but register access 71 is not possible. This connection mode saves one wire and works with any SPI 72 controller. 73 74 Set the ``adi,sdi-pin`` device tree property to ``"high"`` to select this mode. 75 76 :: 77 78 +-------------+ 79 +--------------------| CS | 80 v | | 81 VIO +--------------------+ | HOST | 82 | | CNV | | | 83 +--->| SDI AD4000 SDO |-------->| SDI | 84 | SCK | | | 85 +--------------------+ | | 86 ^ | | 87 +--------------------| SCLK | 88 +-------------+ 89 90 Alternatively, a GPIO may be connected to the device CNV pin. This is similar to 91 the previous wiring configuration but saves the use of a CS line. 92 93 :: 94 95 +-------------+ 96 +--------------------| GPIO | 97 v | | 98 VIO +--------------------+ | HOST | 99 | | CNV | | | 100 +--->| SDI AD4000 SDO |-------->| SDI | 101 | SCK | | | 102 +--------------------+ | | 103 ^ | | 104 +--------------------| SCLK | 105 +-------------+ 106 107 CS mode, 4-wire without busy indicator 108 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 109 110 In datasheet "4-wire" mode, the controller CS line is connected to the ADC SDI 111 pin and a GPIO is connected to the ADC CNV pin. This connection mode may better 112 suit scenarios where multiple ADCs can share one CNV trigger. 113 114 Set ``adi,sdi-pin`` to ``"cs"`` to select this mode. 115 116 117 :: 118 119 +-------------+ 120 + ----------------------------------| CS | 121 | | | 122 | +-------------------| GPIO | 123 | v | | 124 | +--------------------+ | HOST | 125 | | CNV | | | 126 +--->| SDI AD4000 SDO |-------->| SDI | 127 | SCK | | | 128 +--------------------+ | | 129 ^ | | 130 +--------------------| SCLK | 131 +-------------+
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.