xref: /kernel/linux/linux-5.10/drivers/mcb/mcb-lpc.c (revision 8c2ecf20) 
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
16struct priv {
17	struct mcb_bus *bus;
18	struct resource *mem;
19	void __iomem *base;
20};
21
22static 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
95out_mcb_bus:
96	mcb_release_bus(priv->bus);
97	return ret;
98}
99
100static int 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	return 0;
107}
108
109static struct platform_device *mcb_lpc_pdev;
110
111static int mcb_lpc_create_platform_device(const struct dmi_system_id *id)
112{
113	struct resource *res = id->driver_data;
114	int ret;
115
116	mcb_lpc_pdev = platform_device_alloc("mcb-lpc", -1);
117	if (!mcb_lpc_pdev)
118		return -ENOMEM;
119
120	ret = platform_device_add_resources(mcb_lpc_pdev, res, 1);
121	if (ret)
122		goto out_put;
123
124	ret = platform_device_add(mcb_lpc_pdev);
125	if (ret)
126		goto out_put;
127
128	return 0;
129
130out_put:
131	platform_device_put(mcb_lpc_pdev);
132	return ret;
133}
134
135static struct resource sc24_fpga_resource = {
136	.start = 0xe000e000,
137	.end = 0xe000e000 + CHAM_HEADER_SIZE,
138	.flags = IORESOURCE_MEM,
139};
140
141static struct resource sc31_fpga_resource = {
142	.start = 0xf000e000,
143	.end = 0xf000e000 + CHAM_HEADER_SIZE,
144	.flags = IORESOURCE_MEM,
145};
146
147static struct platform_driver mcb_lpc_driver = {
148	.driver		= {
149		.name = "mcb-lpc",
150	},
151	.probe		= mcb_lpc_probe,
152	.remove		= mcb_lpc_remove,
153};
154
155static const struct dmi_system_id mcb_lpc_dmi_table[] = {
156	{
157		.ident = "SC24",
158		.matches = {
159			DMI_MATCH(DMI_SYS_VENDOR, "MEN"),
160			DMI_MATCH(DMI_PRODUCT_VERSION, "14SC24"),
161		},
162		.driver_data = (void *)&sc24_fpga_resource,
163		.callback = mcb_lpc_create_platform_device,
164	},
165	{
166		.ident = "SC31",
167		.matches = {
168			DMI_MATCH(DMI_SYS_VENDOR, "MEN"),
169			DMI_MATCH(DMI_PRODUCT_VERSION, "14SC31"),
170		},
171		.driver_data = (void *)&sc31_fpga_resource,
172		.callback = mcb_lpc_create_platform_device,
173	},
174	{}
175};
176MODULE_DEVICE_TABLE(dmi, mcb_lpc_dmi_table);
177
178static int __init mcb_lpc_init(void)
179{
180	if (!dmi_check_system(mcb_lpc_dmi_table))
181		return -ENODEV;
182
183	return platform_driver_register(&mcb_lpc_driver);
184}
185
186static void __exit mcb_lpc_exit(void)
187{
188	platform_device_unregister(mcb_lpc_pdev);
189	platform_driver_unregister(&mcb_lpc_driver);
190}
191
192module_init(mcb_lpc_init);
193module_exit(mcb_lpc_exit);
194
195MODULE_AUTHOR("Andreas Werner <andreas.werner@men.de>");
196MODULE_LICENSE("GPL");
197MODULE_DESCRIPTION("MCB over LPC support");
198MODULE_IMPORT_NS(MCB);
199