1 /* 2 * Driver for the Analog Devices digital potentiometers (SPI bus) 3 * 4 * Copyright (C) 2010-2011 Michael Hennerich, Analog Devices Inc. 5 * 6 * Licensed under the GPL-2 or later. 7 */ 8 9 #include <linux/spi/spi.h> 10 #include <linux/module.h> 11 12 #include "ad525x_dpot.h" 13 14 /* SPI bus functions */ 15 static int write8(void *client, u8 val) 16 { 17 u8 data = val; 18 19 return spi_write(client, &data, 1); 20 } 21 22 static int write16(void *client, u8 reg, u8 val) 23 { 24 u8 data[2] = {reg, val}; 25 26 return spi_write(client, data, 2); 27 } 28 29 static int write24(void *client, u8 reg, u16 val) 30 { 31 u8 data[3] = {reg, val >> 8, val}; 32 33 return spi_write(client, data, 3); 34 } 35 36 static int read8(void *client) 37 { 38 int ret; 39 u8 data; 40 41 ret = spi_read(client, &data, 1); 42 if (ret < 0) 43 return ret; 44 45 return data; 46 } 47 48 static int read16(void *client, u8 reg) 49 { 50 int ret; 51 u8 buf_rx[2]; 52 53 write16(client, reg, 0); 54 ret = spi_read(client, buf_rx, 2); 55 if (ret < 0) 56 return ret; 57 58 return (buf_rx[0] << 8) | buf_rx[1]; 59 } 60 61 static int read24(void *client, u8 reg) 62 { 63 int ret; 64 u8 buf_rx[3]; 65 66 write24(client, reg, 0); 67 ret = spi_read(client, buf_rx, 3); 68 if (ret < 0) 69 return ret; 70 71 return (buf_rx[1] << 8) | buf_rx[2]; 72 } 73 74 static const struct ad_dpot_bus_ops bops = { 75 .read_d8 = read8, 76 .read_r8d8 = read16, 77 .read_r8d16 = read24, 78 .write_d8 = write8, 79 .write_r8d8 = write16, 80 .write_r8d16 = write24, 81 }; 82 static int ad_dpot_spi_probe(struct spi_device *spi) 83 { 84 struct ad_dpot_bus_data bdata = { 85 .client = spi, 86 .bops = &bops, 87 }; 88 89 return ad_dpot_probe(&spi->dev, &bdata, 90 spi_get_device_id(spi)->driver_data, 91 spi_get_device_id(spi)->name); 92 } 93 94 static int ad_dpot_spi_remove(struct spi_device *spi) 95 { 96 return ad_dpot_remove(&spi->dev); 97 } 98 99 static const struct spi_device_id ad_dpot_spi_id[] = { 100 {"ad5160", AD5160_ID}, 101 {"ad5161", AD5161_ID}, 102 {"ad5162", AD5162_ID}, 103 {"ad5165", AD5165_ID}, 104 {"ad5200", AD5200_ID}, 105 {"ad5201", AD5201_ID}, 106 {"ad5203", AD5203_ID}, 107 {"ad5204", AD5204_ID}, 108 {"ad5206", AD5206_ID}, 109 {"ad5207", AD5207_ID}, 110 {"ad5231", AD5231_ID}, 111 {"ad5232", AD5232_ID}, 112 {"ad5233", AD5233_ID}, 113 {"ad5235", AD5235_ID}, 114 {"ad5260", AD5260_ID}, 115 {"ad5262", AD5262_ID}, 116 {"ad5263", AD5263_ID}, 117 {"ad5290", AD5290_ID}, 118 {"ad5291", AD5291_ID}, 119 {"ad5292", AD5292_ID}, 120 {"ad5293", AD5293_ID}, 121 {"ad7376", AD7376_ID}, 122 {"ad8400", AD8400_ID}, 123 {"ad8402", AD8402_ID}, 124 {"ad8403", AD8403_ID}, 125 {"adn2850", ADN2850_ID}, 126 {"ad5270", AD5270_ID}, 127 {"ad5271", AD5271_ID}, 128 {} 129 }; 130 MODULE_DEVICE_TABLE(spi, ad_dpot_spi_id); 131 132 static struct spi_driver ad_dpot_spi_driver = { 133 .driver = { 134 .name = "ad_dpot", 135 }, 136 .probe = ad_dpot_spi_probe, 137 .remove = ad_dpot_spi_remove, 138 .id_table = ad_dpot_spi_id, 139 }; 140 141 module_spi_driver(ad_dpot_spi_driver); 142 143 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>"); 144 MODULE_DESCRIPTION("digital potentiometer SPI bus driver"); 145 MODULE_LICENSE("GPL"); 146 MODULE_ALIAS("spi:ad_dpot"); 147