1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * uio_aec.c -- simple driver for Adrienne Electronics Corp time code PCI device
4 *
5 * Copyright (C) 2008 Brandon Philips <brandon@ifup.org>
6 */
7
8 #include <linux/kernel.h>
9 #include <linux/module.h>
10 #include <linux/pci.h>
11 #include <linux/init.h>
12 #include <linux/interrupt.h>
13 #include <linux/cdev.h>
14 #include <linux/fs.h>
15 #include <linux/io.h>
16 #include <linux/uaccess.h>
17 #include <linux/uio_driver.h>
18 #include <linux/slab.h>
19
20 #define PCI_VENDOR_ID_AEC 0xaecb
21 #define PCI_DEVICE_ID_AEC_VITCLTC 0x6250
22
23 #define INT_ENABLE_ADDR 0xFC
24 #define INT_ENABLE 0x10
25 #define INT_DISABLE 0x0
26
27 #define INT_MASK_ADDR 0x2E
28 #define INT_MASK_ALL 0x3F
29
30 #define INTA_DRVR_ADDR 0xFE
31 #define INTA_ENABLED_FLAG 0x08
32 #define INTA_FLAG 0x01
33
34 #define MAILBOX 0x0F
35
36 static struct pci_device_id ids[] = {
37 { PCI_DEVICE(PCI_VENDOR_ID_AEC, PCI_DEVICE_ID_AEC_VITCLTC), },
38 { 0, }
39 };
40 MODULE_DEVICE_TABLE(pci, ids);
41
aectc_irq(int irq,struct uio_info * dev_info)42 static irqreturn_t aectc_irq(int irq, struct uio_info *dev_info)
43 {
44 void __iomem *int_flag = dev_info->priv + INTA_DRVR_ADDR;
45 unsigned char status = ioread8(int_flag);
46
47
48 if ((status & INTA_ENABLED_FLAG) && (status & INTA_FLAG)) {
49 /* application writes 0x00 to 0x2F to get next interrupt */
50 status = ioread8(dev_info->priv + MAILBOX);
51 return IRQ_HANDLED;
52 }
53
54 return IRQ_NONE;
55 }
56
print_board_data(struct pci_dev * pdev,struct uio_info * i)57 static void print_board_data(struct pci_dev *pdev, struct uio_info *i)
58 {
59 dev_info(&pdev->dev, "PCI-TC board vendor: %x%x number: %x%x"
60 " revision: %c%c\n",
61 ioread8(i->priv + 0x01),
62 ioread8(i->priv + 0x00),
63 ioread8(i->priv + 0x03),
64 ioread8(i->priv + 0x02),
65 ioread8(i->priv + 0x06),
66 ioread8(i->priv + 0x07));
67 }
68
probe(struct pci_dev * pdev,const struct pci_device_id * id)69 static int probe(struct pci_dev *pdev, const struct pci_device_id *id)
70 {
71 struct uio_info *info;
72 int ret;
73
74 info = devm_kzalloc(&pdev->dev, sizeof(struct uio_info), GFP_KERNEL);
75 if (!info)
76 return -ENOMEM;
77
78 if (pci_enable_device(pdev))
79 return -ENODEV;
80
81 if (pci_request_regions(pdev, "aectc"))
82 goto out_disable;
83
84 info->name = "aectc";
85 info->port[0].start = pci_resource_start(pdev, 0);
86 if (!info->port[0].start)
87 goto out_release;
88 info->priv = pci_iomap(pdev, 0, 0);
89 if (!info->priv)
90 goto out_release;
91 info->port[0].size = pci_resource_len(pdev, 0);
92 info->port[0].porttype = UIO_PORT_GPIO;
93
94 info->version = "0.0.1";
95 info->irq = pdev->irq;
96 info->irq_flags = IRQF_SHARED;
97 info->handler = aectc_irq;
98
99 print_board_data(pdev, info);
100 ret = uio_register_device(&pdev->dev, info);
101 if (ret)
102 goto out_unmap;
103
104 iowrite32(INT_ENABLE, info->priv + INT_ENABLE_ADDR);
105 iowrite8(INT_MASK_ALL, info->priv + INT_MASK_ADDR);
106 if (!(ioread8(info->priv + INTA_DRVR_ADDR)
107 & INTA_ENABLED_FLAG))
108 dev_err(&pdev->dev, "aectc: interrupts not enabled\n");
109
110 pci_set_drvdata(pdev, info);
111
112 return 0;
113
114 out_unmap:
115 pci_iounmap(pdev, info->priv);
116 out_release:
117 pci_release_regions(pdev);
118 out_disable:
119 pci_disable_device(pdev);
120 return -ENODEV;
121 }
122
remove(struct pci_dev * pdev)123 static void remove(struct pci_dev *pdev)
124 {
125 struct uio_info *info = pci_get_drvdata(pdev);
126
127 /* disable interrupts */
128 iowrite8(INT_DISABLE, info->priv + INT_MASK_ADDR);
129 iowrite32(INT_DISABLE, info->priv + INT_ENABLE_ADDR);
130 /* read mailbox to ensure board drops irq */
131 ioread8(info->priv + MAILBOX);
132
133 uio_unregister_device(info);
134 pci_release_regions(pdev);
135 pci_disable_device(pdev);
136 pci_iounmap(pdev, info->priv);
137 }
138
139 static struct pci_driver pci_driver = {
140 .name = "aectc",
141 .id_table = ids,
142 .probe = probe,
143 .remove = remove,
144 };
145
146 module_pci_driver(pci_driver);
147 MODULE_DESCRIPTION("Adrienne Electronics Corp time code PCI device");
148 MODULE_LICENSE("GPL");
149