xref: /openbmc/linux/drivers/mcb/mcb-lpc.c (revision 04dc82e1)
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;
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 		mcb_release_bus(priv->bus);
62 		return ret;
63 	}
64 
65 	dev_dbg(&pdev->dev, "Found %d cells\n", ret);
66 
67 	mcb_bus_add_devices(priv->bus);
68 
69 	return 0;
70 
71 }
72 
73 static int mcb_lpc_remove(struct platform_device *pdev)
74 {
75 	struct priv *priv = platform_get_drvdata(pdev);
76 
77 	mcb_release_bus(priv->bus);
78 
79 	return 0;
80 }
81 
82 static struct platform_device *mcb_lpc_pdev;
83 
84 static int mcb_lpc_create_platform_device(const struct dmi_system_id *id)
85 {
86 	struct resource *res = id->driver_data;
87 	int ret;
88 
89 	mcb_lpc_pdev = platform_device_alloc("mcb-lpc", -1);
90 	if (!mcb_lpc_pdev)
91 		return -ENOMEM;
92 
93 	ret = platform_device_add_resources(mcb_lpc_pdev, res, 1);
94 	if (ret)
95 		goto out_put;
96 
97 	ret = platform_device_add(mcb_lpc_pdev);
98 	if (ret)
99 		goto out_put;
100 
101 	return 0;
102 
103 out_put:
104 	platform_device_put(mcb_lpc_pdev);
105 	return ret;
106 }
107 
108 static struct resource sc24_fpga_resource = {
109 	.start = 0xe000e000,
110 	.end = 0xe000e000 + CHAM_HEADER_SIZE,
111 	.flags = IORESOURCE_MEM,
112 };
113 
114 static struct resource sc31_fpga_resource = {
115 	.start = 0xf000e000,
116 	.end = 0xf000e000 + CHAM_HEADER_SIZE,
117 	.flags = IORESOURCE_MEM,
118 };
119 
120 static struct platform_driver mcb_lpc_driver = {
121 	.driver		= {
122 		.name = "mcb-lpc",
123 	},
124 	.probe		= mcb_lpc_probe,
125 	.remove		= mcb_lpc_remove,
126 };
127 
128 static const struct dmi_system_id mcb_lpc_dmi_table[] = {
129 	{
130 		.ident = "SC24",
131 		.matches = {
132 			DMI_MATCH(DMI_SYS_VENDOR, "MEN"),
133 			DMI_MATCH(DMI_PRODUCT_VERSION, "14SC24"),
134 		},
135 		.driver_data = (void *)&sc24_fpga_resource,
136 		.callback = mcb_lpc_create_platform_device,
137 	},
138 	{
139 		.ident = "SC31",
140 		.matches = {
141 			DMI_MATCH(DMI_SYS_VENDOR, "MEN"),
142 			DMI_MATCH(DMI_PRODUCT_VERSION, "14SC31"),
143 		},
144 		.driver_data = (void *)&sc31_fpga_resource,
145 		.callback = mcb_lpc_create_platform_device,
146 	},
147 	{}
148 };
149 MODULE_DEVICE_TABLE(dmi, mcb_lpc_dmi_table);
150 
151 static int __init mcb_lpc_init(void)
152 {
153 	if (!dmi_check_system(mcb_lpc_dmi_table))
154 		return -ENODEV;
155 
156 	return platform_driver_register(&mcb_lpc_driver);
157 }
158 
159 static void __exit mcb_lpc_exit(void)
160 {
161 	platform_device_unregister(mcb_lpc_pdev);
162 	platform_driver_unregister(&mcb_lpc_driver);
163 }
164 
165 module_init(mcb_lpc_init);
166 module_exit(mcb_lpc_exit);
167 
168 MODULE_AUTHOR("Andreas Werner <andreas.werner@men.de>");
169 MODULE_LICENSE("GPL");
170 MODULE_DESCRIPTION("MCB over LPC support");
171