projects / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 6c536e4c MH |
1 | /* |
| 2 | * Driver for the Analog Devices digital potentiometers (SPI bus) | |
| 3 | * | |
| 4 | * Copyright (C) 2010 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 | static const struct ad_dpot_id ad_dpot_spi_devlist[] = { | |
| 15 | {.name = "ad5160", .devid = AD5160_ID}, | |
| 16 | {.name = "ad5161", .devid = AD5161_ID}, | |
| 17 | {.name = "ad5162", .devid = AD5162_ID}, | |
| 18 | {.name = "ad5165", .devid = AD5165_ID}, | |
| 19 | {.name = "ad5200", .devid = AD5200_ID}, | |
| 20 | {.name = "ad5201", .devid = AD5201_ID}, | |
| 21 | {.name = "ad5203", .devid = AD5203_ID}, | |
| 22 | {.name = "ad5204", .devid = AD5204_ID}, | |
| 23 | {.name = "ad5206", .devid = AD5206_ID}, | |
| 24 | {.name = "ad5207", .devid = AD5207_ID}, | |
| 25 | {.name = "ad5231", .devid = AD5231_ID}, | |
| 26 | {.name = "ad5232", .devid = AD5232_ID}, | |
| 27 | {.name = "ad5233", .devid = AD5233_ID}, | |
| 28 | {.name = "ad5235", .devid = AD5235_ID}, | |
| 29 | {.name = "ad5260", .devid = AD5260_ID}, | |
| 30 | {.name = "ad5262", .devid = AD5262_ID}, | |
| 31 | {.name = "ad5263", .devid = AD5263_ID}, | |
| 32 | {.name = "ad5290", .devid = AD5290_ID}, | |
| 33 | {.name = "ad5291", .devid = AD5291_ID}, | |
| 34 | {.name = "ad5292", .devid = AD5292_ID}, | |
| 35 | {.name = "ad5293", .devid = AD5293_ID}, | |
| 36 | {.name = "ad7376", .devid = AD7376_ID}, | |
| 37 | {.name = "ad8400", .devid = AD8400_ID}, | |
| 38 | {.name = "ad8402", .devid = AD8402_ID}, | |
| 39 | {.name = "ad8403", .devid = AD8403_ID}, | |
| 40 | {.name = "adn2850", .devid = ADN2850_ID}, | |
| 41 | {} | |
| 42 | }; | |
| 43 | ||
| 44 | /* ------------------------------------------------------------------------- */ | |
| 45 | ||
| 46 | /* SPI bus functions */ | |
| 47 | static int write8(void *client, u8 val) | |
| 48 | { | |
| 49 | u8 data = val; | |
| 50 | return spi_write(client, &data, 1); | |
| 51 | } | |
| 52 | ||
| 53 | static int write16(void *client, u8 reg, u8 val) | |
| 54 | { | |
| 55 | u8 data[2] = {reg, val}; | |
| 56 | return spi_write(client, data, 1); | |
| 57 | } | |
| 58 | ||
| 59 | static int write24(void *client, u8 reg, u16 val) | |
| 60 | { | |
| 61 | u8 data[3] = {reg, val >> 8, val}; | |
| 62 | return spi_write(client, data, 1); | |
| 63 | } | |
| 64 | ||
| 65 | static int read8(void *client) | |
| 66 | { | |
| 67 | int ret; | |
| 68 | u8 data; | |
| 69 | ret = spi_read(client, &data, 1); | |
| 70 | if (ret < 0) | |
| 71 | return ret; | |
| 72 | ||
| 73 | return data; | |
| 74 | } | |
| 75 | ||
| 76 | static int read16(void *client, u8 reg) | |
| 77 | { | |
| 78 | int ret; | |
| 79 | u8 buf_rx[2]; | |
| 80 | ||
| 81 | write16(client, reg, 0); | |
| 82 | ret = spi_read(client, buf_rx, 2); | |
| 83 | if (ret < 0) | |
| 84 | return ret; | |
| 85 | ||
| 86 | return (buf_rx[0] << 8) | buf_rx[1]; | |
| 87 | } | |
| 88 | ||
| 89 | static int read24(void *client, u8 reg) | |
| 90 | { | |
| 91 | int ret; | |
| 92 | u8 buf_rx[3]; | |
| 93 | ||
| 94 | write24(client, reg, 0); | |
| 95 | ret = spi_read(client, buf_rx, 3); | |
| 96 | if (ret < 0) | |
| 97 | return ret; | |
| 98 | ||
| 99 | return (buf_rx[1] << 8) | buf_rx[2]; | |
| 100 | } | |
| 101 | ||
| 102 | static const struct ad_dpot_bus_ops bops = { | |
| 103 | .read_d8 = read8, | |
| 104 | .read_r8d8 = read16, | |
| 105 | .read_r8d16 = read24, | |
| 106 | .write_d8 = write8, | |
| 107 | .write_r8d8 = write16, | |
| 108 | .write_r8d16 = write24, | |
| 109 | }; | |
| 110 | ||
| 111 | static const struct ad_dpot_id *dpot_match_id(const struct ad_dpot_id *id, | |
| 112 | char *name) | |
| 113 | { | |
| 114 | while (id->name && id->name[0]) { | |
| 115 | if (strcmp(name, id->name) == 0) | |
| 116 | return id; | |
| 117 | id++; | |
| 118 | } | |
| 119 | return NULL; | |
| 120 | } | |
| 121 | ||
| 122 | static int __devinit ad_dpot_spi_probe(struct spi_device *spi) | |
| 123 | { | |
| 124 | char *name = spi->dev.platform_data; | |
| 125 | const struct ad_dpot_id *dpot_id; | |
| 126 | ||
| 127 | struct ad_dpot_bus_data bdata = { | |
| 128 | .client = spi, | |
| 129 | .bops = &bops, | |
| 130 | }; | |
| 131 | ||
| 132 | dpot_id = dpot_match_id(ad_dpot_spi_devlist, name); | |
| 133 | ||
| 134 | if (dpot_id == NULL) { | |
| 135 | dev_err(&spi->dev, "%s not in supported device list", name); | |
| 136 | return -ENODEV; | |
| 137 | } | |
| 138 | ||
| 139 | return ad_dpot_probe(&spi->dev, &bdata, dpot_id); | |
| 140 | } | |
| 141 | ||
| 142 | static int __devexit ad_dpot_spi_remove(struct spi_device *spi) | |
| 143 | { | |
| 144 | return ad_dpot_remove(&spi->dev); | |
| 145 | } | |
| 146 | ||
| 147 | static struct spi_driver ad_dpot_spi_driver = { | |
| 148 | .driver = { | |
| 149 | .name = "ad_dpot", | |
| 150 | .bus = &spi_bus_type, | |
| 151 | .owner = THIS_MODULE, | |
| 152 | }, | |
| 153 | .probe = ad_dpot_spi_probe, | |
| 154 | .remove = __devexit_p(ad_dpot_spi_remove), | |
| 155 | }; | |
| 156 | ||
| 157 | static int __init ad_dpot_spi_init(void) | |
| 158 | { | |
| 159 | return spi_register_driver(&ad_dpot_spi_driver); | |
| 160 | } | |
| 161 | module_init(ad_dpot_spi_init); | |
| 162 | ||
| 163 | static void __exit ad_dpot_spi_exit(void) | |
| 164 | { | |
| 165 | spi_unregister_driver(&ad_dpot_spi_driver); | |
| 166 | } | |
| 167 | module_exit(ad_dpot_spi_exit); | |
| 168 | ||
| 169 | MODULE_AUTHOR("Michael Hennerich <[email protected]>"); | |
| 170 | MODULE_DESCRIPTION("digital potentiometer SPI bus driver"); | |
| 171 | MODULE_LICENSE("GPL"); | |
| 172 | MODULE_ALIAS("spi:ad_dpot"); |