1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * OF-platform PATA driver
4  *
5  * Copyright (c) 2007  MontaVista Software, Inc.
6  *                     Anton Vorontsov <avorontsov@ru.mvista.com>
7  */
8 
9 #include <linux/kernel.h>
10 #include <linux/module.h>
11 #include <linux/of_address.h>
12 #include <linux/platform_device.h>
13 #include <linux/ata_platform.h>
14 #include <linux/libata.h>
15 
16 #define DRV_NAME "pata_of_platform"
17 
18 static struct scsi_host_template pata_platform_sht = {
19 	ATA_PIO_SHT(DRV_NAME),
20 };
21 
pata_of_platform_probe(struct platform_device * ofdev)22 static int pata_of_platform_probe(struct platform_device *ofdev)
23 {
24 	int ret;
25 	struct device_node *dn = ofdev->dev.of_node;
26 	struct resource io_res;
27 	struct resource ctl_res;
28 	struct resource irq_res;
29 	unsigned int reg_shift = 0;
30 	int pio_mode = 0;
31 	int pio_mask;
32 	bool use16bit;
33 	int irq;
34 
35 	ret = of_address_to_resource(dn, 0, &io_res);
36 	if (ret) {
37 		dev_err(&ofdev->dev, "can't get IO address from "
38 			"device tree\n");
39 		return -EINVAL;
40 	}
41 
42 	ret = of_address_to_resource(dn, 1, &ctl_res);
43 	if (ret) {
44 		dev_err(&ofdev->dev, "can't get CTL address from "
45 			"device tree\n");
46 		return -EINVAL;
47 	}
48 
49 	memset(&irq_res, 0, sizeof(irq_res));
50 
51 	irq = platform_get_irq_optional(ofdev, 0);
52 	if (irq < 0 && irq != -ENXIO)
53 		return irq;
54 	if (irq > 0) {
55 		irq_res.start = irq;
56 		irq_res.end = irq;
57 	}
58 
59 	of_property_read_u32(dn, "reg-shift", &reg_shift);
60 
61 	if (!of_property_read_u32(dn, "pio-mode", &pio_mode)) {
62 		if (pio_mode > 6) {
63 			dev_err(&ofdev->dev, "invalid pio-mode\n");
64 			return -EINVAL;
65 		}
66 	} else {
67 		dev_info(&ofdev->dev, "pio-mode unspecified, assuming PIO0\n");
68 	}
69 
70 	use16bit = of_property_read_bool(dn, "ata-generic,use16bit");
71 
72 	pio_mask = 1 << pio_mode;
73 	pio_mask |= (1 << pio_mode) - 1;
74 
75 	return __pata_platform_probe(&ofdev->dev, &io_res, &ctl_res, irq > 0 ? &irq_res : NULL,
76 				     reg_shift, pio_mask, &pata_platform_sht,
77 				     use16bit);
78 }
79 
80 static const struct of_device_id pata_of_platform_match[] = {
81 	{ .compatible = "ata-generic", },
82 	{ /* sentinel */ }
83 };
84 MODULE_DEVICE_TABLE(of, pata_of_platform_match);
85 
86 static struct platform_driver pata_of_platform_driver = {
87 	.driver = {
88 		.name = DRV_NAME,
89 		.of_match_table = pata_of_platform_match,
90 	},
91 	.probe		= pata_of_platform_probe,
92 	.remove		= ata_platform_remove_one,
93 };
94 
95 module_platform_driver(pata_of_platform_driver);
96 
97 MODULE_DESCRIPTION("OF-platform PATA driver");
98 MODULE_AUTHOR("Anton Vorontsov <avorontsov@ru.mvista.com>");
99 MODULE_LICENSE("GPL");
100