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