1 /*
2 * drivers/uio/uio_pdrv.c
3 *
4 * Copyright (C) 2008 by Digi International Inc.
5 * All rights reserved.
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License version 2 as published by
9 * the Free Software Foundation.
10 */
11 #include <linux/platform_device.h>
12 #include <linux/uio_driver.h>
13 #include <linux/stringify.h>
14 #include <linux/module.h>
15 #include <linux/slab.h>
16
17 #define DRIVER_NAME "uio_pdrv"
18
19 struct uio_platdata {
20 struct uio_info *uioinfo;
21 };
22
uio_pdrv_probe(struct platform_device * pdev)23 static int uio_pdrv_probe(struct platform_device *pdev)
24 {
25 struct uio_info *uioinfo = pdev->dev.platform_data;
26 struct uio_platdata *pdata;
27 struct uio_mem *uiomem;
28 int ret = -ENODEV;
29 int i;
30
31 if (!uioinfo || !uioinfo->name || !uioinfo->version) {
32 dev_dbg(&pdev->dev, "%s: err_uioinfo\n", __func__);
33 goto err_uioinfo;
34 }
35
36 pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
37 if (!pdata) {
38 ret = -ENOMEM;
39 dev_dbg(&pdev->dev, "%s: err_alloc_pdata\n", __func__);
40 goto err_alloc_pdata;
41 }
42
43 pdata->uioinfo = uioinfo;
44
45 uiomem = &uioinfo->mem[0];
46
47 for (i = 0; i < pdev->num_resources; ++i) {
48 struct resource *r = &pdev->resource[i];
49
50 if (r->flags != IORESOURCE_MEM)
51 continue;
52
53 if (uiomem >= &uioinfo->mem[MAX_UIO_MAPS]) {
54 dev_warn(&pdev->dev, "device has more than "
55 __stringify(MAX_UIO_MAPS)
56 " I/O memory resources.\n");
57 break;
58 }
59
60 uiomem->memtype = UIO_MEM_PHYS;
61 uiomem->addr = r->start;
62 uiomem->size = resource_size(r);
63 uiomem->name = r->name;
64 ++uiomem;
65 }
66
67 while (uiomem < &uioinfo->mem[MAX_UIO_MAPS]) {
68 uiomem->size = 0;
69 ++uiomem;
70 }
71
72 pdata->uioinfo->priv = pdata;
73
74 ret = uio_register_device(&pdev->dev, pdata->uioinfo);
75
76 if (ret) {
77 kfree(pdata);
78 err_alloc_pdata:
79 err_uioinfo:
80 return ret;
81 }
82
83 platform_set_drvdata(pdev, pdata);
84
85 return 0;
86 }
87
uio_pdrv_remove(struct platform_device * pdev)88 static int uio_pdrv_remove(struct platform_device *pdev)
89 {
90 struct uio_platdata *pdata = platform_get_drvdata(pdev);
91
92 uio_unregister_device(pdata->uioinfo);
93
94 kfree(pdata);
95
96 return 0;
97 }
98
99 static struct platform_driver uio_pdrv = {
100 .probe = uio_pdrv_probe,
101 .remove = uio_pdrv_remove,
102 .driver = {
103 .name = DRIVER_NAME,
104 .owner = THIS_MODULE,
105 },
106 };
107
108 module_platform_driver(uio_pdrv);
109
110 MODULE_AUTHOR("Uwe Kleine-Koenig");
111 MODULE_DESCRIPTION("Userspace I/O platform driver");
112 MODULE_LICENSE("GPL v2");
113 MODULE_ALIAS("platform:" DRIVER_NAME);
114