Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 1 | /* |
Jonathan Cameron | 10e4a52 | 2011-10-05 15:28:02 +0100 | [diff] [blame] | 2 | * ad2s1200.c simple support for the ADI Resolver to Digital Converters: |
| 3 | * AD2S1200/1205 |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 4 | * |
| 5 | * Copyright (c) 2010-2010 Analog Devices Inc. |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of the GNU General Public License version 2 as |
| 9 | * published by the Free Software Foundation. |
| 10 | * |
| 11 | */ |
| 12 | #include <linux/types.h> |
| 13 | #include <linux/mutex.h> |
| 14 | #include <linux/device.h> |
| 15 | #include <linux/spi/spi.h> |
| 16 | #include <linux/slab.h> |
| 17 | #include <linux/sysfs.h> |
| 18 | #include <linux/delay.h> |
| 19 | #include <linux/gpio.h> |
Paul Gortmaker | 99c9785 | 2011-07-03 15:49:50 -0400 | [diff] [blame] | 20 | #include <linux/module.h> |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 21 | |
Jonathan Cameron | 06458e2 | 2012-04-25 15:54:58 +0100 | [diff] [blame] | 22 | #include <linux/iio/iio.h> |
| 23 | #include <linux/iio/sysfs.h> |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 24 | |
Jonathan Cameron | 10e4a52 | 2011-10-05 15:28:02 +0100 | [diff] [blame] | 25 | #define DRV_NAME "ad2s1200" |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 26 | |
| 27 | /* input pin sample and rdvel is controlled by driver */ |
Jonathan Cameron | 10e4a52 | 2011-10-05 15:28:02 +0100 | [diff] [blame] | 28 | #define AD2S1200_PN 2 |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 29 | |
| 30 | /* input clock on serial interface */ |
Jonathan Cameron | 10e4a52 | 2011-10-05 15:28:02 +0100 | [diff] [blame] | 31 | #define AD2S1200_HZ 8192000 |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 32 | /* clock period in nano second */ |
Jonathan Cameron | 10e4a52 | 2011-10-05 15:28:02 +0100 | [diff] [blame] | 33 | #define AD2S1200_TSCLK (1000000000/AD2S1200_HZ) |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 34 | |
Jonathan Cameron | 10e4a52 | 2011-10-05 15:28:02 +0100 | [diff] [blame] | 35 | struct ad2s1200_state { |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 36 | struct mutex lock; |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 37 | struct spi_device *sdev; |
Jonathan Cameron | 8f2bd83 | 2011-06-27 13:07:52 +0100 | [diff] [blame] | 38 | int sample; |
| 39 | int rdvel; |
| 40 | u8 rx[2] ____cacheline_aligned; |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 41 | }; |
| 42 | |
Jonathan Cameron | 9c5ed82 | 2011-10-05 15:28:01 +0100 | [diff] [blame] | 43 | static int ad2s1200_read_raw(struct iio_dev *indio_dev, |
| 44 | struct iio_chan_spec const *chan, |
| 45 | int *val, |
| 46 | int *val2, |
| 47 | long m) |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 48 | { |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 49 | int ret = 0; |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 50 | s16 vel; |
Jonathan Cameron | 10e4a52 | 2011-10-05 15:28:02 +0100 | [diff] [blame] | 51 | struct ad2s1200_state *st = iio_priv(indio_dev); |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 52 | |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 53 | mutex_lock(&st->lock); |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 54 | gpio_set_value(st->sample, 0); |
Jonathan Cameron | 10e4a52 | 2011-10-05 15:28:02 +0100 | [diff] [blame] | 55 | /* delay (6 * AD2S1200_TSCLK + 20) nano seconds */ |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 56 | udelay(1); |
| 57 | gpio_set_value(st->sample, 1); |
Jonathan Cameron | 9c5ed82 | 2011-10-05 15:28:01 +0100 | [diff] [blame] | 58 | gpio_set_value(st->rdvel, !!(chan->type == IIO_ANGL)); |
Jonathan Cameron | 8f2bd83 | 2011-06-27 13:07:52 +0100 | [diff] [blame] | 59 | ret = spi_read(st->sdev, st->rx, 2); |
Jonathan Cameron | 9c5ed82 | 2011-10-05 15:28:01 +0100 | [diff] [blame] | 60 | if (ret < 0) { |
| 61 | mutex_unlock(&st->lock); |
| 62 | return ret; |
Jonathan Cameron | 8f2bd83 | 2011-06-27 13:07:52 +0100 | [diff] [blame] | 63 | } |
Jonathan Cameron | 9c5ed82 | 2011-10-05 15:28:01 +0100 | [diff] [blame] | 64 | |
| 65 | switch (chan->type) { |
| 66 | case IIO_ANGL: |
| 67 | *val = (((u16)(st->rx[0])) << 4) | ((st->rx[1] & 0xF0) >> 4); |
| 68 | break; |
| 69 | case IIO_ANGL_VEL: |
| 70 | vel = (((s16)(st->rx[0])) << 4) | ((st->rx[1] & 0xF0) >> 4); |
| 71 | vel = (vel << 4) >> 4; |
| 72 | *val = vel; |
| 73 | default: |
| 74 | mutex_unlock(&st->lock); |
| 75 | return -EINVAL; |
| 76 | } |
Jonathan Cameron | 10e4a52 | 2011-10-05 15:28:02 +0100 | [diff] [blame] | 77 | /* delay (2 * AD2S1200_TSCLK + 20) ns for sample pulse */ |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 78 | udelay(1); |
| 79 | mutex_unlock(&st->lock); |
Jonathan Cameron | 9c5ed82 | 2011-10-05 15:28:01 +0100 | [diff] [blame] | 80 | return IIO_VAL_INT; |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 81 | } |
| 82 | |
Jonathan Cameron | 9c5ed82 | 2011-10-05 15:28:01 +0100 | [diff] [blame] | 83 | static const struct iio_chan_spec ad2s1200_channels[] = { |
| 84 | { |
| 85 | .type = IIO_ANGL, |
| 86 | .indexed = 1, |
| 87 | .channel = 0, |
Jonathan Cameron | 910b51f | 2013-02-27 19:41:20 +0000 | [diff] [blame] | 88 | .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), |
Jonathan Cameron | 9c5ed82 | 2011-10-05 15:28:01 +0100 | [diff] [blame] | 89 | }, { |
| 90 | .type = IIO_ANGL_VEL, |
| 91 | .indexed = 1, |
| 92 | .channel = 0, |
Jonathan Cameron | 910b51f | 2013-02-27 19:41:20 +0000 | [diff] [blame] | 93 | .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), |
Jonathan Cameron | 9c5ed82 | 2011-10-05 15:28:01 +0100 | [diff] [blame] | 94 | } |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 95 | }; |
| 96 | |
Jonathan Cameron | 10e4a52 | 2011-10-05 15:28:02 +0100 | [diff] [blame] | 97 | static const struct iio_info ad2s1200_info = { |
Jonathan Cameron | 9c5ed82 | 2011-10-05 15:28:01 +0100 | [diff] [blame] | 98 | .read_raw = &ad2s1200_read_raw, |
Jonathan Cameron | 6fe8135 | 2011-05-18 14:42:37 +0100 | [diff] [blame] | 99 | .driver_module = THIS_MODULE, |
| 100 | }; |
| 101 | |
Bill Pemberton | 4ae1c61 | 2012-11-19 13:21:57 -0500 | [diff] [blame] | 102 | static int ad2s1200_probe(struct spi_device *spi) |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 103 | { |
Jonathan Cameron | 10e4a52 | 2011-10-05 15:28:02 +0100 | [diff] [blame] | 104 | struct ad2s1200_state *st; |
Jonathan Cameron | 8f2bd83 | 2011-06-27 13:07:52 +0100 | [diff] [blame] | 105 | struct iio_dev *indio_dev; |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 106 | int pn, ret = 0; |
| 107 | unsigned short *pins = spi->dev.platform_data; |
| 108 | |
Jonathan Cameron | 10e4a52 | 2011-10-05 15:28:02 +0100 | [diff] [blame] | 109 | for (pn = 0; pn < AD2S1200_PN; pn++) |
Sachin Kamat | 8d1b0b4 | 2013-09-11 10:55:00 +0100 | [diff] [blame] | 110 | ret = devm_gpio_request_one(&spi->dev, pins[pn], GPIOF_DIR_OUT, |
| 111 | DRV_NAME); |
| 112 | if (ret) { |
Sachin Kamat | a20df3f | 2013-09-11 10:55:00 +0100 | [diff] [blame] | 113 | dev_err(&spi->dev, "request gpio pin %d failed\n", |
| 114 | pins[pn]); |
Sachin Kamat | 8d1b0b4 | 2013-09-11 10:55:00 +0100 | [diff] [blame] | 115 | return ret; |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 116 | } |
Sachin Kamat | 8d1b0b4 | 2013-09-11 10:55:00 +0100 | [diff] [blame] | 117 | indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*st)); |
| 118 | if (!indio_dev) |
| 119 | return -ENOMEM; |
Jonathan Cameron | 8f2bd83 | 2011-06-27 13:07:52 +0100 | [diff] [blame] | 120 | spi_set_drvdata(spi, indio_dev); |
| 121 | st = iio_priv(indio_dev); |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 122 | mutex_init(&st->lock); |
| 123 | st->sdev = spi; |
| 124 | st->sample = pins[0]; |
| 125 | st->rdvel = pins[1]; |
| 126 | |
Jonathan Cameron | 8f2bd83 | 2011-06-27 13:07:52 +0100 | [diff] [blame] | 127 | indio_dev->dev.parent = &spi->dev; |
Jonathan Cameron | 10e4a52 | 2011-10-05 15:28:02 +0100 | [diff] [blame] | 128 | indio_dev->info = &ad2s1200_info; |
Jonathan Cameron | 8f2bd83 | 2011-06-27 13:07:52 +0100 | [diff] [blame] | 129 | indio_dev->modes = INDIO_DIRECT_MODE; |
Jonathan Cameron | 9c5ed82 | 2011-10-05 15:28:01 +0100 | [diff] [blame] | 130 | indio_dev->channels = ad2s1200_channels; |
| 131 | indio_dev->num_channels = ARRAY_SIZE(ad2s1200_channels); |
Jonathan Cameron | 10e4a52 | 2011-10-05 15:28:02 +0100 | [diff] [blame] | 132 | indio_dev->name = spi_get_device_id(spi)->name; |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 133 | |
Jonathan Cameron | 8f2bd83 | 2011-06-27 13:07:52 +0100 | [diff] [blame] | 134 | ret = iio_device_register(indio_dev); |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 135 | if (ret) |
Sachin Kamat | 8d1b0b4 | 2013-09-11 10:55:00 +0100 | [diff] [blame] | 136 | return ret; |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 137 | |
Jonathan Cameron | 10e4a52 | 2011-10-05 15:28:02 +0100 | [diff] [blame] | 138 | spi->max_speed_hz = AD2S1200_HZ; |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 139 | spi->mode = SPI_MODE_3; |
| 140 | spi_setup(spi); |
| 141 | |
| 142 | return 0; |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 143 | } |
| 144 | |
Bill Pemberton | 447d4f2 | 2012-11-19 13:26:37 -0500 | [diff] [blame] | 145 | static int ad2s1200_remove(struct spi_device *spi) |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 146 | { |
Jonathan Cameron | 8f2bd83 | 2011-06-27 13:07:52 +0100 | [diff] [blame] | 147 | iio_device_unregister(spi_get_drvdata(spi)); |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 148 | |
| 149 | return 0; |
| 150 | } |
| 151 | |
Jonathan Cameron | 10e4a52 | 2011-10-05 15:28:02 +0100 | [diff] [blame] | 152 | static const struct spi_device_id ad2s1200_id[] = { |
| 153 | { "ad2s1200" }, |
| 154 | { "ad2s1205" }, |
| 155 | {} |
| 156 | }; |
Lars-Peter Clausen | 55e4390 | 2011-11-16 08:53:31 +0100 | [diff] [blame] | 157 | MODULE_DEVICE_TABLE(spi, ad2s1200_id); |
Jonathan Cameron | 10e4a52 | 2011-10-05 15:28:02 +0100 | [diff] [blame] | 158 | |
| 159 | static struct spi_driver ad2s1200_driver = { |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 160 | .driver = { |
| 161 | .name = DRV_NAME, |
| 162 | .owner = THIS_MODULE, |
| 163 | }, |
Jonathan Cameron | 10e4a52 | 2011-10-05 15:28:02 +0100 | [diff] [blame] | 164 | .probe = ad2s1200_probe, |
Bill Pemberton | e543acf | 2012-11-19 13:21:38 -0500 | [diff] [blame] | 165 | .remove = ad2s1200_remove, |
Jonathan Cameron | 10e4a52 | 2011-10-05 15:28:02 +0100 | [diff] [blame] | 166 | .id_table = ad2s1200_id, |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 167 | }; |
Lars-Peter Clausen | ae6ae6f | 2011-11-16 10:13:39 +0100 | [diff] [blame] | 168 | module_spi_driver(ad2s1200_driver); |
Graf Yang | ffd7a62 | 2010-10-27 21:44:20 -0400 | [diff] [blame] | 169 | |
| 170 | MODULE_AUTHOR("Graff Yang <graff.yang@gmail.com>"); |
| 171 | MODULE_DESCRIPTION("Analog Devices AD2S1200/1205 Resolver to Digital SPI driver"); |
| 172 | MODULE_LICENSE("GPL v2"); |