1 /*
2  * OF-platform PATA driver
3  *
4  * Copyright (c) 2007  MontaVista Software, Inc.
5  *                     Anton Vorontsov <avorontsov@ru.mvista.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License (Version 2) as
9  * published by the Free Software Foundation.
10  */
11 
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/of_address.h>
15 #include <linux/platform_device.h>
16 #include <linux/ata_platform.h>
17 #include <linux/libata.h>
18 
19 static int pata_of_platform_probe(struct platform_device *ofdev)
20 {
21 	int ret;
22 	struct device_node *dn = ofdev->dev.of_node;
23 	struct resource io_res;
24 	struct resource ctl_res;
25 	struct resource *irq_res;
26 	unsigned int reg_shift = 0;
27 	int pio_mode = 0;
28 	int pio_mask;
29 	const u32 *prop;
30 
31 	ret = of_address_to_resource(dn, 0, &io_res);
32 	if (ret) {
33 		dev_err(&ofdev->dev, "can't get IO address from "
34 			"device tree\n");
35 		return -EINVAL;
36 	}
37 
38 	if (of_device_is_compatible(dn, "electra-ide")) {
39 		/* Altstatus is really at offset 0x3f6 from the primary window
40 		 * on electra-ide. Adjust ctl_res and io_res accordingly.
41 		 */
42 		ctl_res = io_res;
43 		ctl_res.start = ctl_res.start+0x3f6;
44 		io_res.end = ctl_res.start-1;
45 	} else {
46 		ret = of_address_to_resource(dn, 1, &ctl_res);
47 		if (ret) {
48 			dev_err(&ofdev->dev, "can't get CTL address from "
49 				"device tree\n");
50 			return -EINVAL;
51 		}
52 	}
53 
54 	irq_res = platform_get_resource(ofdev, IORESOURCE_IRQ, 0);
55 	if (irq_res)
56 		irq_res->flags = 0;
57 
58 	prop = of_get_property(dn, "reg-shift", NULL);
59 	if (prop)
60 		reg_shift = be32_to_cpup(prop);
61 
62 	prop = of_get_property(dn, "pio-mode", NULL);
63 	if (prop) {
64 		pio_mode = be32_to_cpup(prop);
65 		if (pio_mode > 6) {
66 			dev_err(&ofdev->dev, "invalid pio-mode\n");
67 			return -EINVAL;
68 		}
69 	} else {
70 		dev_info(&ofdev->dev, "pio-mode unspecified, assuming PIO0\n");
71 	}
72 
73 	pio_mask = 1 << pio_mode;
74 	pio_mask |= (1 << pio_mode) - 1;
75 
76 	return __pata_platform_probe(&ofdev->dev, &io_res, &ctl_res, irq_res,
77 				     reg_shift, pio_mask);
78 }
79 
80 static struct of_device_id pata_of_platform_match[] = {
81 	{ .compatible = "ata-generic", },
82 	{ .compatible = "electra-ide", },
83 	{},
84 };
85 MODULE_DEVICE_TABLE(of, pata_of_platform_match);
86 
87 static struct platform_driver pata_of_platform_driver = {
88 	.driver = {
89 		.name = "pata_of_platform",
90 		.owner = THIS_MODULE,
91 		.of_match_table = pata_of_platform_match,
92 	},
93 	.probe		= pata_of_platform_probe,
94 	.remove		= ata_platform_remove_one,
95 };
96 
97 module_platform_driver(pata_of_platform_driver);
98 
99 MODULE_DESCRIPTION("OF-platform PATA driver");
100 MODULE_AUTHOR("Anton Vorontsov <avorontsov@ru.mvista.com>");
101 MODULE_LICENSE("GPL");
102