drivers/staging/iio/adc/ad7606_spi.c

   1 /*
   2  * AD7606 SPI ADC driver
   3  *
   4  * Copyright 2011 Analog Devices Inc.
   5  *
   6  * Licensed under the GPL-2.
   7  */
   8
   9 #include <linux/module.h>
  10 #include <linux/spi/spi.h>
  11 #include <linux/types.h>
  12 #include <linux/err.h>
  13 #include "ad7606.h"
  14
  15 #define MAX_SPI_FREQ_HZ         23500000        /* VDRIVE above 4.75 V */
  16
  17 static int ad7606_spi_read_block(struct device *dev,
  18                                  int count, void *buf)
  19 {
  20         struct spi_device *spi = to_spi_device(dev);
  21         int i, ret;
  22         unsigned short *data = buf;
  23
  24         ret = spi_read(spi, (u8 *)buf, count * 2);
  25         if (ret < 0) {
  26                 dev_err(&spi->dev, "SPI read error\n");
  27                 return ret;
  28         }
  29
  30         for (i = 0; i < count; i++)
  31                 data[i] = be16_to_cpu(data[i]);
  32
  33         return 0;
  34 }
  35
  36 static const struct ad7606_bus_ops ad7606_spi_bops = {
  37         .read_block     = ad7606_spi_read_block,
  38 };
  39
  40 static int __devinit ad7606_spi_probe(struct spi_device *spi)
  41 {
  42         struct ad7606_state *st;
  43
  44         st = ad7606_probe(&spi->dev, spi->irq, NULL,
  45                            spi_get_device_id(spi)->driver_data,
  46                            &ad7606_spi_bops);
  47
  48         if (IS_ERR(st))
  49                 return PTR_ERR(st);
  50
  51         spi_set_drvdata(spi, st);
  52
  53         return 0;
  54 }
  55
  56 static int __devexit ad7606_spi_remove(struct spi_device *spi)
  57 {
  58         struct ad7606_state *st = dev_get_drvdata(&spi->dev);
  59
  60         return ad7606_remove(st);
  61 }
  62
  63 #ifdef CONFIG_PM
  64 static int ad7606_spi_suspend(struct device *dev)
  65 {
  66         struct ad7606_state *st = dev_get_drvdata(dev);
  67
  68         ad7606_suspend(st);
  69
  70         return 0;
  71 }
  72
  73 static int ad7606_spi_resume(struct device *dev)
  74 {
  75         struct ad7606_state *st = dev_get_drvdata(dev);
  76
  77         ad7606_resume(st);
  78
  79         return 0;
  80 }
  81
  82 static const struct dev_pm_ops ad7606_pm_ops = {
  83         .suspend = ad7606_spi_suspend,
  84         .resume  = ad7606_spi_resume,
  85 };
  86 #define AD7606_SPI_PM_OPS (&ad7606_pm_ops)
  87
  88 #else
  89 #define AD7606_SPI_PM_OPS NULL
  90 #endif
  91
  92 static const struct spi_device_id ad7606_id[] = {
  93         {"ad7606-8", ID_AD7606_8},
  94         {"ad7606-6", ID_AD7606_6},
  95         {"ad7606-4", ID_AD7606_4},
  96         {}
  97 };
  98
  99 static struct spi_driver ad7606_driver = {
 100         .driver = {
 101                 .name = "ad7606",
 102                 .bus = &spi_bus_type,
 103                 .owner = THIS_MODULE,
 104                 .pm    = AD7606_SPI_PM_OPS,
 105         },
 106         .probe = ad7606_spi_probe,
 107         .remove = __devexit_p(ad7606_spi_remove),
 108         .id_table = ad7606_id,
 109 };
 110
 111 static int __init ad7606_spi_init(void)
 112 {
 113         return spi_register_driver(&ad7606_driver);
 114 }
 115 module_init(ad7606_spi_init);
 116
 117 static void __exit ad7606_spi_exit(void)
 118 {
 119         spi_unregister_driver(&ad7606_driver);
 120 }
 121 module_exit(ad7606_spi_exit);
 122
 123 MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
 124 MODULE_DESCRIPTION("Analog Devices AD7606 ADC");
 125 MODULE_LICENSE("GPL v2");
 126 MODULE_ALIAS("spi:ad7606_spi");