drivers/mfd/ucb1400_core.c

   1 /*
   2  * Core functions for:
   3  *  Philips UCB1400 multifunction chip
   4  *
   5  * Based on ucb1400_ts.c:
   6  *  Author:     Nicolas Pitre
   7  *  Created:    September 25, 2006
   8  *  Copyright:  MontaVista Software, Inc.
   9  *
  10  * Spliting done by: Marek Vasut <marek.vasut@gmail.com>
  11  * If something doesnt work and it worked before spliting, e-mail me,
  12  * dont bother Nicolas please ;-)
  13  *
  14  * This program is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License version 2 as
  16  * published by the Free Software Foundation.
  17  *
  18  * This code is heavily based on ucb1x00-*.c copyrighted by Russell King
  19  * covering the UCB1100, UCB1200 and UCB1300..  Support for the UCB1400 has
  20  * been made separate from ucb1x00-core/ucb1x00-ts on Russell's request.
  21  */
  22
  23 #include <linux/module.h>
  24 #include <linux/ucb1400.h>
  25
  26 unsigned int ucb1400_adc_read(struct snd_ac97 *ac97, u16 adc_channel,
  27                 int adcsync)
  28 {
  29         unsigned int val;
  30
  31         if (adcsync)
  32                 adc_channel |= UCB_ADC_SYNC_ENA;
  33
  34         ucb1400_reg_write(ac97, UCB_ADC_CR, UCB_ADC_ENA | adc_channel);
  35         ucb1400_reg_write(ac97, UCB_ADC_CR, UCB_ADC_ENA | adc_channel |
  36                         UCB_ADC_START);
  37
  38         while (!((val = ucb1400_reg_read(ac97, UCB_ADC_DATA))
  39                                 & UCB_ADC_DAT_VALID))
  40                 schedule_timeout_uninterruptible(1);
  41
  42         return val & UCB_ADC_DAT_MASK;
  43 }
  44 EXPORT_SYMBOL_GPL(ucb1400_adc_read);
  45
  46 static int ucb1400_core_probe(struct device *dev)
  47 {
  48         int err;
  49         struct ucb1400 *ucb;
  50         struct ucb1400_ts ucb_ts;
  51         struct snd_ac97 *ac97;
  52
  53         memset(&ucb_ts, 0, sizeof(ucb_ts));
  54
  55         ucb = kzalloc(sizeof(struct ucb1400), GFP_KERNEL);
  56         if (!ucb) {
  57                 err = -ENOMEM;
  58                 goto err;
  59         }
  60
  61         dev_set_drvdata(dev, ucb);
  62
  63         ac97 = to_ac97_t(dev);
  64
  65         ucb_ts.id = ucb1400_reg_read(ac97, UCB_ID);
  66         if (ucb_ts.id != UCB_ID_1400) {
  67                 err = -ENODEV;
  68                 goto err0;
  69         }
  70
  71         /* TOUCHSCREEN */
  72         ucb_ts.ac97 = ac97;
  73         ucb->ucb1400_ts = platform_device_alloc("ucb1400_ts", -1);
  74         if (!ucb->ucb1400_ts) {
  75                 err = -ENOMEM;
  76                 goto err0;
  77         }
  78         err = platform_device_add_data(ucb->ucb1400_ts, &ucb_ts,
  79                                         sizeof(ucb_ts));
  80         if (err)
  81                 goto err1;
  82         err = platform_device_add(ucb->ucb1400_ts);
  83         if (err)
  84                 goto err1;
  85
  86         return 0;
  87
  88 err1:
  89         platform_device_put(ucb->ucb1400_ts);
  90 err0:
  91         kfree(ucb);
  92 err:
  93         return err;
  94 }
  95
  96 static int ucb1400_core_remove(struct device *dev)
  97 {
  98         struct ucb1400 *ucb = dev_get_drvdata(dev);
  99
 100         platform_device_unregister(ucb->ucb1400_ts);
 101         kfree(ucb);
 102         return 0;
 103 }
 104
 105 static struct device_driver ucb1400_core_driver = {
 106         .name   = "ucb1400_core",
 107         .bus    = &ac97_bus_type,
 108         .probe  = ucb1400_core_probe,
 109         .remove = ucb1400_core_remove,
 110 };
 111
 112 static int __init ucb1400_core_init(void)
 113 {
 114         return driver_register(&ucb1400_core_driver);
 115 }
 116
 117 static void __exit ucb1400_core_exit(void)
 118 {
 119         driver_unregister(&ucb1400_core_driver);
 120 }
 121
 122 module_init(ucb1400_core_init);
 123 module_exit(ucb1400_core_exit);
 124
 125 MODULE_DESCRIPTION("Philips UCB1400 driver");
 126 MODULE_LICENSE("GPL");