LXR linux/drivers/uio/uio

   1/*
   2 * uio_aec.c -- simple driver for Adrienne Electronics Corp time code PCI device
   3 *
   4 * Copyright (C) 2008 Brandon Philips <brandon@ifup.org>
   5 *
   6 *   This program is free software; you can redistribute it and/or modify it
   7 *   under the terms of the GNU General Public License version 2 as published
   8 *   by the Free Software Foundation.
   9 *
  10 *   This program is distributed in the hope that it will be useful,
  11 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 *   GNU General Public License for more details.
  14 *
  15 *   You should have received a copy of the GNU General Public License along
  16 *   with this program; if not, write to the Free Software Foundation, Inc., 59
  17 *   Temple Place, Suite 330, Boston, MA 02111-1307, USA.
  18 */
  19
  20#include <linux/kernel.h>
  21#include <linux/module.h>
  22#include <linux/pci.h>
  23#include <linux/init.h>
  24#include <linux/interrupt.h>
  25#include <linux/cdev.h>
  26#include <linux/fs.h>
  27#include <linux/io.h>
  28#include <linux/uaccess.h>
  29#include <linux/uio_driver.h>
  30#include <linux/slab.h>
  31
  32#define PCI_VENDOR_ID_AEC 0xaecb
  33#define PCI_DEVICE_ID_AEC_VITCLTC 0x6250
  34
  35#define INT_ENABLE_ADDR         0xFC
  36#define INT_ENABLE              0x10
  37#define INT_DISABLE             0x0
  38
  39#define INT_MASK_ADDR           0x2E
  40#define INT_MASK_ALL            0x3F
  41
  42#define INTA_DRVR_ADDR          0xFE
  43#define INTA_ENABLED_FLAG       0x08
  44#define INTA_FLAG               0x01
  45
  46#define MAILBOX                 0x0F
  47
  48static struct pci_device_id ids[] = {
  49        { PCI_DEVICE(PCI_VENDOR_ID_AEC, PCI_DEVICE_ID_AEC_VITCLTC), },
  50        { 0, }
  51};
  52MODULE_DEVICE_TABLE(pci, ids);
  53
  54static irqreturn_t aectc_irq(int irq, struct uio_info *dev_info)
  55{
  56        void __iomem *int_flag = dev_info->priv + INTA_DRVR_ADDR;
  57        unsigned char status = ioread8(int_flag);
  58
  59
  60        if ((status & INTA_ENABLED_FLAG) && (status & INTA_FLAG)) {
  61                /* application writes 0x00 to 0x2F to get next interrupt */
  62                status = ioread8(dev_info->priv + MAILBOX);
  63                return IRQ_HANDLED;
  64        }
  65
  66        return IRQ_NONE;
  67}
  68
  69static void print_board_data(struct pci_dev *pdev, struct uio_info *i)
  70{
  71        dev_info(&pdev->dev, "PCI-TC board vendor: %x%x number: %x%x"
  72                " revision: %c%c\n",
  73                ioread8(i->priv + 0x01),
  74                ioread8(i->priv + 0x00),
  75                ioread8(i->priv + 0x03),
  76                ioread8(i->priv + 0x02),
  77                ioread8(i->priv + 0x06),
  78                ioread8(i->priv + 0x07));
  79}
  80
  81static int probe(struct pci_dev *pdev, const struct pci_device_id *id)
  82{
  83        struct uio_info *info;
  84        int ret;
  85
  86        info = kzalloc(sizeof(struct uio_info), GFP_KERNEL);
  87        if (!info)
  88                return -ENOMEM;
  89
  90        if (pci_enable_device(pdev))
  91                goto out_free;
  92
  93        if (pci_request_regions(pdev, "aectc"))
  94                goto out_disable;
  95
  96        info->name = "aectc";
  97        info->port[0].start = pci_resource_start(pdev, 0);
  98        if (!info->port[0].start)
  99                goto out_release;
 100        info->priv = pci_iomap(pdev, 0, 0);
 101        if (!info->priv)
 102                goto out_release;
 103        info->port[0].size = pci_resource_len(pdev, 0);
 104        info->port[0].porttype = UIO_PORT_GPIO;
 105
 106        info->version = "0.0.1";
 107        info->irq = pdev->irq;
 108        info->irq_flags = IRQF_SHARED;
 109        info->handler = aectc_irq;
 110
 111        print_board_data(pdev, info);
 112        ret = uio_register_device(&pdev->dev, info);
 113        if (ret)
 114                goto out_unmap;
 115
 116        iowrite32(INT_ENABLE, info->priv + INT_ENABLE_ADDR);
 117        iowrite8(INT_MASK_ALL, info->priv + INT_MASK_ADDR);
 118        if (!(ioread8(info->priv + INTA_DRVR_ADDR)
 119                        & INTA_ENABLED_FLAG))
 120                dev_err(&pdev->dev, "aectc: interrupts not enabled\n");
 121
 122        pci_set_drvdata(pdev, info);
 123
 124        return 0;
 125
 126out_unmap:
 127        pci_iounmap(pdev, info->priv);
 128out_release:
 129        pci_release_regions(pdev);
 130out_disable:
 131        pci_disable_device(pdev);
 132out_free:
 133        kfree(info);
 134        return -ENODEV;
 135}
 136
 137static void remove(struct pci_dev *pdev)
 138{
 139        struct uio_info *info = pci_get_drvdata(pdev);
 140
 141        /* disable interrupts */
 142        iowrite8(INT_DISABLE, info->priv + INT_MASK_ADDR);
 143        iowrite32(INT_DISABLE, info->priv + INT_ENABLE_ADDR);
 144        /* read mailbox to ensure board drops irq */
 145        ioread8(info->priv + MAILBOX);
 146
 147        uio_unregister_device(info);
 148        pci_release_regions(pdev);
 149        pci_disable_device(pdev);
 150        iounmap(info->priv);
 151
 152        kfree(info);
 153}
 154
 155static struct pci_driver pci_driver = {
 156        .name = "aectc",
 157        .id_table = ids,
 158        .probe = probe,
 159        .remove = remove,
 160};
 161
 162module_pci_driver(pci_driver);
 163MODULE_LICENSE("GPL");
 164