xref: /openbmc/linux/drivers/mcb/mcb-lpc.c (revision e2c75e76)
1 /*
2  * MEN Chameleon Bus.
3  *
4  * Copyright (C) 2014 MEN Mikroelektronik GmbH (www.men.de)
5  * Author: Andreas Werner <andreas.werner@men.de>
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 as published by the Free
9  * Software Foundation; version 2 of the License.
10  */
11 
12 #include <linux/platform_device.h>
13 #include <linux/module.h>
14 #include <linux/dmi.h>
15 #include <linux/mcb.h>
16 #include <linux/io.h>
17 #include "mcb-internal.h"
18 
19 struct priv {
20 	struct mcb_bus *bus;
21 	struct resource *mem;
22 	void __iomem *base;
23 };
24 
25 static int mcb_lpc_probe(struct platform_device *pdev)
26 {
27 	struct resource *res;
28 	struct priv *priv;
29 	int ret = 0;
30 
31 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
32 	if (!priv)
33 		return -ENOMEM;
34 
35 	priv->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
36 	if (!priv->mem) {
37 		dev_err(&pdev->dev, "No Memory resource\n");
38 		return -ENODEV;
39 	}
40 
41 	res = devm_request_mem_region(&pdev->dev, priv->mem->start,
42 				      resource_size(priv->mem),
43 				      KBUILD_MODNAME);
44 	if (!res) {
45 		dev_err(&pdev->dev, "Failed to request IO memory\n");
46 		return -EBUSY;
47 	}
48 
49 	priv->base = devm_ioremap(&pdev->dev, priv->mem->start,
50 				  resource_size(priv->mem));
51 	if (!priv->base) {
52 		dev_err(&pdev->dev, "Cannot ioremap\n");
53 		return -ENOMEM;
54 	}
55 
56 	platform_set_drvdata(pdev, priv);
57 
58 	priv->bus = mcb_alloc_bus(&pdev->dev);
59 	if (IS_ERR(priv->bus))
60 		return PTR_ERR(priv->bus);
61 
62 	ret = chameleon_parse_cells(priv->bus, priv->mem->start, priv->base);
63 	if (ret < 0) {
64 		mcb_release_bus(priv->bus);
65 		return ret;
66 	}
67 
68 	dev_dbg(&pdev->dev, "Found %d cells\n", ret);
69 
70 	mcb_bus_add_devices(priv->bus);
71 
72 	return 0;
73 
74 }
75 
76 static int mcb_lpc_remove(struct platform_device *pdev)
77 {
78 	struct priv *priv = platform_get_drvdata(pdev);
79 
80 	mcb_release_bus(priv->bus);
81 
82 	return 0;
83 }
84 
85 static struct platform_device *mcb_lpc_pdev;
86 
87 static int mcb_lpc_create_platform_device(const struct dmi_system_id *id)
88 {
89 	struct resource *res = id->driver_data;
90 	int ret;
91 
92 	mcb_lpc_pdev = platform_device_alloc("mcb-lpc", -1);
93 	if (!mcb_lpc_pdev)
94 		return -ENOMEM;
95 
96 	ret = platform_device_add_resources(mcb_lpc_pdev, res, 1);
97 	if (ret)
98 		goto out_put;
99 
100 	ret = platform_device_add(mcb_lpc_pdev);
101 	if (ret)
102 		goto out_put;
103 
104 	return 0;
105 
106 out_put:
107 	platform_device_put(mcb_lpc_pdev);
108 	return ret;
109 }
110 
111 static struct resource sc24_fpga_resource = {
112 	.start = 0xe000e000,
113 	.end = 0xe000e000 + CHAM_HEADER_SIZE,
114 	.flags = IORESOURCE_MEM,
115 };
116 
117 static struct resource sc31_fpga_resource = {
118 	.start = 0xf000e000,
119 	.end = 0xf000e000 + CHAM_HEADER_SIZE,
120 	.flags = IORESOURCE_MEM,
121 };
122 
123 static struct platform_driver mcb_lpc_driver = {
124 	.driver		= {
125 		.name = "mcb-lpc",
126 	},
127 	.probe		= mcb_lpc_probe,
128 	.remove		= mcb_lpc_remove,
129 };
130 
131 static const struct dmi_system_id mcb_lpc_dmi_table[] = {
132 	{
133 		.ident = "SC24",
134 		.matches = {
135 			DMI_MATCH(DMI_SYS_VENDOR, "MEN"),
136 			DMI_MATCH(DMI_PRODUCT_VERSION, "14SC24"),
137 		},
138 		.driver_data = (void *)&sc24_fpga_resource,
139 		.callback = mcb_lpc_create_platform_device,
140 	},
141 	{
142 		.ident = "SC31",
143 		.matches = {
144 			DMI_MATCH(DMI_SYS_VENDOR, "MEN"),
145 			DMI_MATCH(DMI_PRODUCT_VERSION, "14SC31"),
146 		},
147 		.driver_data = (void *)&sc31_fpga_resource,
148 		.callback = mcb_lpc_create_platform_device,
149 	},
150 	{}
151 };
152 MODULE_DEVICE_TABLE(dmi, mcb_lpc_dmi_table);
153 
154 static int __init mcb_lpc_init(void)
155 {
156 	if (!dmi_check_system(mcb_lpc_dmi_table))
157 		return -ENODEV;
158 
159 	return platform_driver_register(&mcb_lpc_driver);
160 }
161 
162 static void __exit mcb_lpc_exit(void)
163 {
164 	platform_device_unregister(mcb_lpc_pdev);
165 	platform_driver_unregister(&mcb_lpc_driver);
166 }
167 
168 module_init(mcb_lpc_init);
169 module_exit(mcb_lpc_exit);
170 
171 MODULE_AUTHOR("Andreas Werner <andreas.werner@men.de>");
172 MODULE_LICENSE("GPL");
173 MODULE_DESCRIPTION("MCB over LPC support");
174