xref: /openbmc/linux/drivers/mfd/lpc_sch.c (revision 4800cd83)
1 /*
2  *  lpc_sch.c - LPC interface for Intel Poulsbo SCH
3  *
4  *  LPC bridge function of the Intel SCH contains many other
5  *  functional units, such as Interrupt controllers, Timers,
6  *  Power Management, System Management, GPIO, RTC, and LPC
7  *  Configuration Registers.
8  *
9  *  Copyright (c) 2010 CompuLab Ltd
10  *  Author: Denis Turischev <denis@compulab.co.il>
11  *
12  *  This program is free software; you can redistribute it and/or modify
13  *  it under the terms of the GNU General Public License 2 as published
14  *  by the Free Software Foundation.
15  *
16  *  This program is distributed in the hope that it will be useful,
17  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
18  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19  *  GNU General Public License for more details.
20  *
21  *  You should have received a copy of the GNU General Public License
22  *  along with this program; see the file COPYING.  If not, write to
23  *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
24  */
25 
26 #include <linux/init.h>
27 #include <linux/kernel.h>
28 #include <linux/module.h>
29 #include <linux/errno.h>
30 #include <linux/acpi.h>
31 #include <linux/pci.h>
32 #include <linux/mfd/core.h>
33 
34 #define SMBASE		0x40
35 #define SMBUS_IO_SIZE	64
36 
37 #define GPIOBASE	0x44
38 #define GPIO_IO_SIZE	64
39 
40 static struct resource smbus_sch_resource = {
41 		.flags = IORESOURCE_IO,
42 };
43 
44 
45 static struct resource gpio_sch_resource = {
46 		.flags = IORESOURCE_IO,
47 };
48 
49 static struct mfd_cell lpc_sch_cells[] = {
50 	{
51 		.name = "isch_smbus",
52 		.num_resources = 1,
53 		.resources = &smbus_sch_resource,
54 	},
55 	{
56 		.name = "sch_gpio",
57 		.num_resources = 1,
58 		.resources = &gpio_sch_resource,
59 	},
60 };
61 
62 static struct pci_device_id lpc_sch_ids[] = {
63 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SCH_LPC) },
64 	{ 0, }
65 };
66 MODULE_DEVICE_TABLE(pci, lpc_sch_ids);
67 
68 static int __devinit lpc_sch_probe(struct pci_dev *dev,
69 				const struct pci_device_id *id)
70 {
71 	unsigned int base_addr_cfg;
72 	unsigned short base_addr;
73 
74 	pci_read_config_dword(dev, SMBASE, &base_addr_cfg);
75 	if (!(base_addr_cfg & (1 << 31))) {
76 		dev_err(&dev->dev, "Decode of the SMBus I/O range disabled\n");
77 		return -ENODEV;
78 	}
79 	base_addr = (unsigned short)base_addr_cfg;
80 	if (base_addr == 0) {
81 		dev_err(&dev->dev, "I/O space for SMBus uninitialized\n");
82 		return -ENODEV;
83 	}
84 
85 	smbus_sch_resource.start = base_addr;
86 	smbus_sch_resource.end = base_addr + SMBUS_IO_SIZE - 1;
87 
88 	pci_read_config_dword(dev, GPIOBASE, &base_addr_cfg);
89 	if (!(base_addr_cfg & (1 << 31))) {
90 		dev_err(&dev->dev, "Decode of the GPIO I/O range disabled\n");
91 		return -ENODEV;
92 	}
93 	base_addr = (unsigned short)base_addr_cfg;
94 	if (base_addr == 0) {
95 		dev_err(&dev->dev, "I/O space for GPIO uninitialized\n");
96 		return -ENODEV;
97 	}
98 
99 	gpio_sch_resource.start = base_addr;
100 	gpio_sch_resource.end = base_addr + GPIO_IO_SIZE - 1;
101 
102 	return mfd_add_devices(&dev->dev, -1,
103 			lpc_sch_cells, ARRAY_SIZE(lpc_sch_cells), NULL, 0);
104 }
105 
106 static void __devexit lpc_sch_remove(struct pci_dev *dev)
107 {
108 	mfd_remove_devices(&dev->dev);
109 }
110 
111 static struct pci_driver lpc_sch_driver = {
112 	.name		= "lpc_sch",
113 	.id_table	= lpc_sch_ids,
114 	.probe		= lpc_sch_probe,
115 	.remove		= __devexit_p(lpc_sch_remove),
116 };
117 
118 static int __init lpc_sch_init(void)
119 {
120 	return pci_register_driver(&lpc_sch_driver);
121 }
122 
123 static void __exit lpc_sch_exit(void)
124 {
125 	pci_unregister_driver(&lpc_sch_driver);
126 }
127 
128 module_init(lpc_sch_init);
129 module_exit(lpc_sch_exit);
130 
131 MODULE_AUTHOR("Denis Turischev <denis@compulab.co.il>");
132 MODULE_DESCRIPTION("LPC interface for Intel Poulsbo SCH");
133 MODULE_LICENSE("GPL");
134