xref: /linux/drivers/mcb/mcb-lpc.c (revision cfee1b50775869de9076d021ea11a8438854dcba)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * MEN Chameleon Bus.
4  *
5  * Copyright (C) 2014 MEN Mikroelektronik GmbH (www.men.de)
6  * Author: Andreas Werner <andreas.werner@men.de>
7  */
8 
9 #include <linux/platform_device.h>
10 #include <linux/module.h>
11 #include <linux/dmi.h>
12 #include <linux/mcb.h>
13 #include <linux/io.h>
14 #include "mcb-internal.h"
15 
16 struct priv {
17 	struct mcb_bus *bus;
18 	struct resource *mem;
19 	void __iomem *base;
20 };
21 
22 static int mcb_lpc_probe(struct platform_device *pdev)
23 {
24 	struct resource *res;
25 	struct priv *priv;
26 	int ret = 0, table_size;
27 
28 	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
29 	if (!priv)
30 		return -ENOMEM;
31 
32 	priv->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
33 	if (!priv->mem) {
34 		dev_err(&pdev->dev, "No Memory resource\n");
35 		return -ENODEV;
36 	}
37 
38 	res = devm_request_mem_region(&pdev->dev, priv->mem->start,
39 				      resource_size(priv->mem),
40 				      KBUILD_MODNAME);
41 	if (!res) {
42 		dev_err(&pdev->dev, "Failed to request IO memory\n");
43 		return -EBUSY;
44 	}
45 
46 	priv->base = devm_ioremap(&pdev->dev, priv->mem->start,
47 				  resource_size(priv->mem));
48 	if (!priv->base) {
49 		dev_err(&pdev->dev, "Cannot ioremap\n");
50 		return -ENOMEM;
51 	}
52 
53 	platform_set_drvdata(pdev, priv);
54 
55 	priv->bus = mcb_alloc_bus(&pdev->dev);
56 	if (IS_ERR(priv->bus))
57 		return PTR_ERR(priv->bus);
58 
59 	ret = chameleon_parse_cells(priv->bus, priv->mem->start, priv->base);
60 	if (ret < 0) {
61 		goto out_mcb_bus;
62 	}
63 
64 	table_size = ret;
65 
66 	if (table_size < CHAM_HEADER_SIZE) {
67 		/* Release the previous resources */
68 		devm_iounmap(&pdev->dev, priv->base);
69 		devm_release_mem_region(&pdev->dev, priv->mem->start, resource_size(priv->mem));
70 
71 		/* Then, allocate it again with the actual chameleon table size */
72 		res = devm_request_mem_region(&pdev->dev, priv->mem->start,
73 					      table_size,
74 					      KBUILD_MODNAME);
75 		if (!res) {
76 			dev_err(&pdev->dev, "Failed to request PCI memory\n");
77 			ret = -EBUSY;
78 			goto out_mcb_bus;
79 		}
80 
81 		priv->base = devm_ioremap(&pdev->dev, priv->mem->start, table_size);
82 		if (!priv->base) {
83 			dev_err(&pdev->dev, "Cannot ioremap\n");
84 			ret = -ENOMEM;
85 			goto out_mcb_bus;
86 		}
87 
88 		platform_set_drvdata(pdev, priv);
89 	}
90 
91 	mcb_bus_add_devices(priv->bus);
92 
93 	return 0;
94 
95 out_mcb_bus:
96 	mcb_release_bus(priv->bus);
97 	return ret;
98 }
99 
100 static void mcb_lpc_remove(struct platform_device *pdev)
101 {
102 	struct priv *priv = platform_get_drvdata(pdev);
103 
104 	mcb_release_bus(priv->bus);
105 }
106 
107 static struct platform_device *mcb_lpc_pdev;
108 
109 static int mcb_lpc_create_platform_device(const struct dmi_system_id *id)
110 {
111 	struct resource *res = id->driver_data;
112 	int ret;
113 
114 	mcb_lpc_pdev = platform_device_alloc("mcb-lpc", -1);
115 	if (!mcb_lpc_pdev)
116 		return -ENOMEM;
117 
118 	ret = platform_device_add_resources(mcb_lpc_pdev, res, 1);
119 	if (ret)
120 		goto out_put;
121 
122 	ret = platform_device_add(mcb_lpc_pdev);
123 	if (ret)
124 		goto out_put;
125 
126 	return 0;
127 
128 out_put:
129 	platform_device_put(mcb_lpc_pdev);
130 	return ret;
131 }
132 
133 static struct resource sc24_fpga_resource = DEFINE_RES_MEM(0xe000e000, CHAM_HEADER_SIZE);
134 static struct resource sc31_fpga_resource = DEFINE_RES_MEM(0xf000e000, CHAM_HEADER_SIZE);
135 
136 static struct platform_driver mcb_lpc_driver = {
137 	.driver		= {
138 		.name = "mcb-lpc",
139 	},
140 	.probe		= mcb_lpc_probe,
141 	.remove_new	= mcb_lpc_remove,
142 };
143 
144 static const struct dmi_system_id mcb_lpc_dmi_table[] = {
145 	{
146 		.ident = "SC24",
147 		.matches = {
148 			DMI_MATCH(DMI_SYS_VENDOR, "MEN"),
149 			DMI_MATCH(DMI_PRODUCT_VERSION, "14SC24"),
150 		},
151 		.driver_data = (void *)&sc24_fpga_resource,
152 		.callback = mcb_lpc_create_platform_device,
153 	},
154 	{
155 		.ident = "SC31",
156 		.matches = {
157 			DMI_MATCH(DMI_SYS_VENDOR, "MEN"),
158 			DMI_MATCH(DMI_PRODUCT_VERSION, "14SC31"),
159 		},
160 		.driver_data = (void *)&sc31_fpga_resource,
161 		.callback = mcb_lpc_create_platform_device,
162 	},
163 	{}
164 };
165 MODULE_DEVICE_TABLE(dmi, mcb_lpc_dmi_table);
166 
167 static int __init mcb_lpc_init(void)
168 {
169 	if (!dmi_check_system(mcb_lpc_dmi_table))
170 		return -ENODEV;
171 
172 	return platform_driver_register(&mcb_lpc_driver);
173 }
174 
175 static void __exit mcb_lpc_exit(void)
176 {
177 	platform_device_unregister(mcb_lpc_pdev);
178 	platform_driver_unregister(&mcb_lpc_driver);
179 }
180 
181 module_init(mcb_lpc_init);
182 module_exit(mcb_lpc_exit);
183 
184 MODULE_AUTHOR("Andreas Werner <andreas.werner@men.de>");
185 MODULE_LICENSE("GPL");
186 MODULE_DESCRIPTION("MCB over LPC support");
187 MODULE_IMPORT_NS(MCB);
188