projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| bc0a409c TR |
1 | /* |
| 2 | * Copyright (C) 2012 Avionic Design GmbH | |
| 3 | * | |
| 4 | * This program is free software; you can redistribute it and/or modify | |
| 5 | * it under the terms of the GNU General Public License version 2 as | |
| 6 | * published by the Free Software Foundation. | |
| 7 | */ | |
| 8 | ||
| 9 | #include <linux/err.h> | |
| 10 | #include <linux/i2c.h> | |
| 11 | #include <linux/module.h> | |
| 1f100e80 | 12 | #include <linux/of.h> |
| bc0a409c TR |
13 | |
| 14 | #include <linux/iio/iio.h> | |
| 15 | #include <linux/regulator/consumer.h> | |
| 16 | ||
| 17 | struct adc081c { | |
| 18 | struct i2c_client *i2c; | |
| 19 | struct regulator *ref; | |
| 20 | }; | |
| 21 | ||
| 22 | #define REG_CONV_RES 0x00 | |
| 23 | ||
| 24 | static int adc081c_read_raw(struct iio_dev *iio, | |
| 25 | struct iio_chan_spec const *channel, int *value, | |
| 26 | int *shift, long mask) | |
| 27 | { | |
| 28 | struct adc081c *adc = iio_priv(iio); | |
| 29 | int err; | |
| 30 | ||
| 31 | switch (mask) { | |
| 32 | case IIO_CHAN_INFO_RAW: | |
| 33 | err = i2c_smbus_read_word_swapped(adc->i2c, REG_CONV_RES); | |
| 34 | if (err < 0) | |
| 35 | return err; | |
| 36 | ||
| 37 | *value = (err >> 4) & 0xff; | |
| 38 | return IIO_VAL_INT; | |
| 39 | ||
| 40 | case IIO_CHAN_INFO_SCALE: | |
| 41 | err = regulator_get_voltage(adc->ref); | |
| 42 | if (err < 0) | |
| 43 | return err; | |
| 44 | ||
| 45 | *value = err / 1000; | |
| 46 | *shift = 8; | |
| 47 | ||
| 48 | return IIO_VAL_FRACTIONAL_LOG2; | |
| 49 | ||
| 50 | default: | |
| 51 | break; | |
| 52 | } | |
| 53 | ||
| 54 | return -EINVAL; | |
| 55 | } | |
| 56 | ||
| 57 | static const struct iio_chan_spec adc081c_channel = { | |
| 58 | .type = IIO_VOLTAGE, | |
| c8fe38a7 JC |
59 | .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), |
| 60 | .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), | |
| bc0a409c TR |
61 | }; |
| 62 | ||
| 63 | static const struct iio_info adc081c_info = { | |
| 64 | .read_raw = adc081c_read_raw, | |
| 65 | .driver_module = THIS_MODULE, | |
| 66 | }; | |
| 67 | ||
| 68 | static int adc081c_probe(struct i2c_client *client, | |
| 69 | const struct i2c_device_id *id) | |
| 70 | { | |
| 71 | struct iio_dev *iio; | |
| 72 | struct adc081c *adc; | |
| 73 | int err; | |
| 74 | ||
| 75 | if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA)) | |
| 76 | return -ENODEV; | |
| 77 | ||
| 99e94b6d | 78 | iio = devm_iio_device_alloc(&client->dev, sizeof(*adc)); |
| bc0a409c TR |
79 | if (!iio) |
| 80 | return -ENOMEM; | |
| 81 | ||
| 82 | adc = iio_priv(iio); | |
| 83 | adc->i2c = client; | |
| 84 | ||
| 99e94b6d SK |
85 | adc->ref = devm_regulator_get(&client->dev, "vref"); |
| 86 | if (IS_ERR(adc->ref)) | |
| 87 | return PTR_ERR(adc->ref); | |
| bc0a409c TR |
88 | |
| 89 | err = regulator_enable(adc->ref); | |
| 90 | if (err < 0) | |
| 99e94b6d | 91 | return err; |
| bc0a409c TR |
92 | |
| 93 | iio->dev.parent = &client->dev; | |
| 94 | iio->name = dev_name(&client->dev); | |
| 95 | iio->modes = INDIO_DIRECT_MODE; | |
| 96 | iio->info = &adc081c_info; | |
| 97 | ||
| 98 | iio->channels = &adc081c_channel; | |
| 99 | iio->num_channels = 1; | |
| 100 | ||
| 101 | err = iio_device_register(iio); | |
| 102 | if (err < 0) | |
| 103 | goto regulator_disable; | |
| 104 | ||
| 105 | i2c_set_clientdata(client, iio); | |
| 106 | ||
| 107 | return 0; | |
| 108 | ||
| 109 | regulator_disable: | |
| 110 | regulator_disable(adc->ref); | |
| bc0a409c TR |
111 | |
| 112 | return err; | |
| 113 | } | |
| 114 | ||
| 115 | static int adc081c_remove(struct i2c_client *client) | |
| 116 | { | |
| 117 | struct iio_dev *iio = i2c_get_clientdata(client); | |
| 118 | struct adc081c *adc = iio_priv(iio); | |
| 119 | ||
| 120 | iio_device_unregister(iio); | |
| 121 | regulator_disable(adc->ref); | |
| bc0a409c TR |
122 | |
| 123 | return 0; | |
| 124 | } | |
| 125 | ||
| 126 | static const struct i2c_device_id adc081c_id[] = { | |
| 127 | { "adc081c", 0 }, | |
| 128 | { } | |
| 129 | }; | |
| 130 | MODULE_DEVICE_TABLE(i2c, adc081c_id); | |
| 131 | ||
| 132 | #ifdef CONFIG_OF | |
| 133 | static const struct of_device_id adc081c_of_match[] = { | |
| 134 | { .compatible = "ti,adc081c" }, | |
| 135 | { } | |
| 136 | }; | |
| 137 | MODULE_DEVICE_TABLE(of, adc081c_of_match); | |
| 138 | #endif | |
| 139 | ||
| 140 | static struct i2c_driver adc081c_driver = { | |
| 141 | .driver = { | |
| 142 | .name = "adc081c", | |
| 143 | .owner = THIS_MODULE, | |
| 144 | .of_match_table = of_match_ptr(adc081c_of_match), | |
| 145 | }, | |
| 146 | .probe = adc081c_probe, | |
| 147 | .remove = adc081c_remove, | |
| 148 | .id_table = adc081c_id, | |
| 149 | }; | |
| 150 | module_i2c_driver(adc081c_driver); | |
| 151 | ||
| 152 | MODULE_AUTHOR("Thierry Reding <thierry.reding@avionic-design.de>"); | |
| 153 | MODULE_DESCRIPTION("Texas Instruments ADC081C021/027 driver"); | |
| 154 | MODULE_LICENSE("GPL v2"); |