projects / linux-block.git / blame
| Commit | Line | Data |
|---|---|---|
| b886d83c | 1 | // SPDX-License-Identifier: GPL-2.0-only |
| 74aeac4d JT |
2 | /* |
| 3 | * MEN 16z188 Analog to Digial Converter | |
| 4 | * | |
| 5 | * Copyright (C) 2014 MEN Mikroelektronik GmbH (www.men.de) | |
| 6 | * Author: Johannes Thumshirn <johannes.thumshirn@men.de> | |
| 74aeac4d JT |
7 | */ |
| 8 | ||
| 9 | #include <linux/kernel.h> | |
| 10 | #include <linux/module.h> | |
| 11 | #include <linux/mcb.h> | |
| 35272754 | 12 | #include <linux/io.h> |
| 74aeac4d JT |
13 | #include <linux/iio/iio.h> |
| 14 | ||
| 15 | #define Z188_ADC_MAX_CHAN 8 | |
| 16 | #define Z188_ADC_GAIN 0x0700000 | |
| 17 | #define Z188_MODE_VOLTAGE BIT(27) | |
| 18 | #define Z188_CFG_AUTO 0x1 | |
| 19 | #define Z188_CTRL_REG 0x40 | |
| 20 | ||
| 21 | #define ADC_DATA(x) (((x) >> 2) & 0x7ffffc) | |
| 22 | #define ADC_OVR(x) ((x) & 0x1) | |
| 23 | ||
| 24 | struct z188_adc { | |
| 25 | struct resource *mem; | |
| 26 | void __iomem *base; | |
| 27 | }; | |
| 28 | ||
| 29 | #define Z188_ADC_CHANNEL(idx) { \ | |
| 30 | .type = IIO_VOLTAGE, \ | |
| 31 | .indexed = 1, \ | |
| 32 | .channel = (idx), \ | |
| 33 | .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ | |
| 34 | } | |
| 35 | ||
| 36 | static const struct iio_chan_spec z188_adc_iio_channels[] = { | |
| 37 | Z188_ADC_CHANNEL(0), | |
| 38 | Z188_ADC_CHANNEL(1), | |
| 39 | Z188_ADC_CHANNEL(2), | |
| 40 | Z188_ADC_CHANNEL(3), | |
| 41 | Z188_ADC_CHANNEL(4), | |
| 42 | Z188_ADC_CHANNEL(5), | |
| 43 | Z188_ADC_CHANNEL(6), | |
| 44 | Z188_ADC_CHANNEL(7), | |
| 45 | }; | |
| 46 | ||
| 47 | static int z188_iio_read_raw(struct iio_dev *iio_dev, | |
| 48 | struct iio_chan_spec const *chan, | |
| 49 | int *val, | |
| 50 | int *val2, | |
| 51 | long info) | |
| 52 | { | |
| 53 | struct z188_adc *adc = iio_priv(iio_dev); | |
| 54 | int ret; | |
| 55 | u16 tmp; | |
| 56 | ||
| 57 | switch (info) { | |
| 58 | case IIO_CHAN_INFO_RAW: | |
| 59 | tmp = readw(adc->base + chan->channel * 4); | |
| 60 | ||
| 61 | if (ADC_OVR(tmp)) { | |
| 62 | dev_info(&iio_dev->dev, | |
| 63 | "Oversampling error on ADC channel %d\n", | |
| 64 | chan->channel); | |
| 65 | return -EIO; | |
| 66 | } | |
| 67 | *val = ADC_DATA(tmp); | |
| 68 | ret = IIO_VAL_INT; | |
| 69 | break; | |
| 70 | default: | |
| 71 | ret = -EINVAL; | |
| 72 | break; | |
| 73 | } | |
| 74 | ||
| 75 | return ret; | |
| 76 | } | |
| 77 | ||
| 52ceb773 | 78 | static const struct iio_info z188_adc_info = { |
| 74aeac4d | 79 | .read_raw = &z188_iio_read_raw, |
| 74aeac4d JT |
80 | }; |
| 81 | ||
| 82 | static void men_z188_config_channels(void __iomem *addr) | |
| 83 | { | |
| 84 | int i; | |
| 85 | u32 cfg; | |
| 86 | u32 ctl; | |
| 87 | ||
| 88 | ctl = readl(addr + Z188_CTRL_REG); | |
| 89 | ctl |= Z188_CFG_AUTO; | |
| 90 | writel(ctl, addr + Z188_CTRL_REG); | |
| 91 | ||
| 92 | for (i = 0; i < Z188_ADC_MAX_CHAN; i++) { | |
| 93 | cfg = readl(addr + i); | |
| 94 | cfg &= ~Z188_ADC_GAIN; | |
| 95 | cfg |= Z188_MODE_VOLTAGE; | |
| 96 | writel(cfg, addr + i); | |
| 97 | } | |
| 98 | } | |
| 99 | ||
| 100 | static int men_z188_probe(struct mcb_device *dev, | |
| 101 | const struct mcb_device_id *id) | |
| 102 | { | |
| 103 | struct z188_adc *adc; | |
| 104 | struct iio_dev *indio_dev; | |
| 105 | struct resource *mem; | |
| 106 | ||
| 107 | indio_dev = devm_iio_device_alloc(&dev->dev, sizeof(struct z188_adc)); | |
| 108 | if (!indio_dev) | |
| 109 | return -ENOMEM; | |
| 110 | ||
| 111 | adc = iio_priv(indio_dev); | |
| 112 | indio_dev->name = "z188-adc"; | |
| 113 | indio_dev->dev.parent = &dev->dev; | |
| 114 | indio_dev->info = &z188_adc_info; | |
| 115 | indio_dev->modes = INDIO_DIRECT_MODE; | |
| 116 | indio_dev->channels = z188_adc_iio_channels; | |
| 117 | indio_dev->num_channels = ARRAY_SIZE(z188_adc_iio_channels); | |
| 118 | ||
| 119 | mem = mcb_request_mem(dev, "z188-adc"); | |
| e94f62e7 DC |
120 | if (IS_ERR(mem)) |
| 121 | return PTR_ERR(mem); | |
| 74aeac4d JT |
122 | |
| 123 | adc->base = ioremap(mem->start, resource_size(mem)); | |
| 124 | if (adc->base == NULL) | |
| 125 | goto err; | |
| 126 | ||
| 127 | men_z188_config_channels(adc->base); | |
| 128 | ||
| 129 | adc->mem = mem; | |
| 130 | mcb_set_drvdata(dev, indio_dev); | |
| 131 | ||
| 132 | return iio_device_register(indio_dev); | |
| 133 | ||
| 134 | err: | |
| 135 | mcb_release_mem(mem); | |
| 136 | return -ENXIO; | |
| 137 | } | |
| 138 | ||
| 139 | static void men_z188_remove(struct mcb_device *dev) | |
| 140 | { | |
| 141 | struct iio_dev *indio_dev = mcb_get_drvdata(dev); | |
| 142 | struct z188_adc *adc = iio_priv(indio_dev); | |
| 143 | ||
| 144 | iio_device_unregister(indio_dev); | |
| 145 | iounmap(adc->base); | |
| 146 | mcb_release_mem(adc->mem); | |
| 147 | } | |
| 148 | ||
| 149 | static const struct mcb_device_id men_z188_ids[] = { | |
| 150 | { .device = 0xbc }, | |
| fbbba1f8 | 151 | { } |
| 74aeac4d JT |
152 | }; |
| 153 | MODULE_DEVICE_TABLE(mcb, men_z188_ids); | |
| 154 | ||
| 155 | static struct mcb_driver men_z188_driver = { | |
| 156 | .driver = { | |
| 157 | .name = "z188-adc", | |
| 158 | .owner = THIS_MODULE, | |
| 159 | }, | |
| 160 | .probe = men_z188_probe, | |
| 161 | .remove = men_z188_remove, | |
| 162 | .id_table = men_z188_ids, | |
| 163 | }; | |
| 164 | module_mcb_driver(men_z188_driver); | |
| 165 | ||
| 166 | MODULE_AUTHOR("Johannes Thumshirn <johannes.thumshirn@men.de>"); | |
| 167 | MODULE_LICENSE("GPL"); | |
| 168 | MODULE_DESCRIPTION("IIO ADC driver for MEN 16z188 ADC Core"); | |
| 169 | MODULE_ALIAS("mcb:16z188"); | |
| 891e6036 | 170 | MODULE_IMPORT_NS(MCB); |