xref: /openbmc/linux/drivers/mfd/lpc_sch.c (revision 206a81c1)
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/kernel.h>
27 #include <linux/module.h>
28 #include <linux/errno.h>
29 #include <linux/acpi.h>
30 #include <linux/pci.h>
31 #include <linux/mfd/core.h>
32 
33 #define SMBASE		0x40
34 #define SMBUS_IO_SIZE	64
35 
36 #define GPIOBASE	0x44
37 #define GPIO_IO_SIZE	64
38 #define GPIO_IO_SIZE_CENTERTON	128
39 
40 #define WDTBASE		0x84
41 #define WDT_IO_SIZE	64
42 
43 static struct resource smbus_sch_resource = {
44 		.flags = IORESOURCE_IO,
45 };
46 
47 static struct resource gpio_sch_resource = {
48 		.flags = IORESOURCE_IO,
49 };
50 
51 static struct resource wdt_sch_resource = {
52 		.flags = IORESOURCE_IO,
53 };
54 
55 static struct mfd_cell lpc_sch_cells[3];
56 
57 static struct mfd_cell isch_smbus_cell = {
58 	.name = "isch_smbus",
59 	.num_resources = 1,
60 	.resources = &smbus_sch_resource,
61 	.ignore_resource_conflicts = true,
62 };
63 
64 static struct mfd_cell sch_gpio_cell = {
65 	.name = "sch_gpio",
66 	.num_resources = 1,
67 	.resources = &gpio_sch_resource,
68 	.ignore_resource_conflicts = true,
69 };
70 
71 static struct mfd_cell wdt_sch_cell = {
72 	.name = "ie6xx_wdt",
73 	.num_resources = 1,
74 	.resources = &wdt_sch_resource,
75 	.ignore_resource_conflicts = true,
76 };
77 
78 static const struct pci_device_id lpc_sch_ids[] = {
79 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SCH_LPC) },
80 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ITC_LPC) },
81 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_CENTERTON_ILB) },
82 	{ 0, }
83 };
84 MODULE_DEVICE_TABLE(pci, lpc_sch_ids);
85 
86 static int lpc_sch_probe(struct pci_dev *dev,
87 				const struct pci_device_id *id)
88 {
89 	unsigned int base_addr_cfg;
90 	unsigned short base_addr;
91 	int i, cells = 0;
92 	int ret;
93 
94 	pci_read_config_dword(dev, SMBASE, &base_addr_cfg);
95 	base_addr = 0;
96 	if (!(base_addr_cfg & (1 << 31)))
97 		dev_warn(&dev->dev, "Decode of the SMBus I/O range disabled\n");
98 	else
99 		base_addr = (unsigned short)base_addr_cfg;
100 
101 	if (base_addr == 0) {
102 		dev_warn(&dev->dev, "I/O space for SMBus uninitialized\n");
103 	} else {
104 		lpc_sch_cells[cells++] = isch_smbus_cell;
105 		smbus_sch_resource.start = base_addr;
106 		smbus_sch_resource.end = base_addr + SMBUS_IO_SIZE - 1;
107 	}
108 
109 	pci_read_config_dword(dev, GPIOBASE, &base_addr_cfg);
110 	base_addr = 0;
111 	if (!(base_addr_cfg & (1 << 31)))
112 		dev_warn(&dev->dev, "Decode of the GPIO I/O range disabled\n");
113 	else
114 		base_addr = (unsigned short)base_addr_cfg;
115 
116 	if (base_addr == 0) {
117 		dev_warn(&dev->dev, "I/O space for GPIO uninitialized\n");
118 	} else {
119 		lpc_sch_cells[cells++] = sch_gpio_cell;
120 		gpio_sch_resource.start = base_addr;
121 		if (id->device == PCI_DEVICE_ID_INTEL_CENTERTON_ILB)
122 			gpio_sch_resource.end = base_addr + GPIO_IO_SIZE_CENTERTON - 1;
123 		else
124 			gpio_sch_resource.end = base_addr + GPIO_IO_SIZE - 1;
125 	}
126 
127 	if (id->device == PCI_DEVICE_ID_INTEL_ITC_LPC
128 	    || id->device == PCI_DEVICE_ID_INTEL_CENTERTON_ILB) {
129 		pci_read_config_dword(dev, WDTBASE, &base_addr_cfg);
130 		base_addr = 0;
131 		if (!(base_addr_cfg & (1 << 31)))
132 			dev_warn(&dev->dev, "Decode of the WDT I/O range disabled\n");
133 		else
134 			base_addr = (unsigned short)base_addr_cfg;
135 		if (base_addr == 0)
136 			dev_warn(&dev->dev, "I/O space for WDT uninitialized\n");
137 		else {
138 			lpc_sch_cells[cells++] = wdt_sch_cell;
139 			wdt_sch_resource.start = base_addr;
140 			wdt_sch_resource.end = base_addr + WDT_IO_SIZE - 1;
141 		}
142 	}
143 
144 	if (WARN_ON(cells > ARRAY_SIZE(lpc_sch_cells))) {
145 		dev_err(&dev->dev, "Cell count exceeds array size");
146 		return -ENODEV;
147 	}
148 
149 	if (cells == 0) {
150 		dev_err(&dev->dev, "All decode registers disabled.\n");
151 		return -ENODEV;
152 	}
153 
154 	for (i = 0; i < cells; i++)
155 		lpc_sch_cells[i].id = id->device;
156 
157 	ret = mfd_add_devices(&dev->dev, 0, lpc_sch_cells, cells, NULL, 0, NULL);
158 	if (ret)
159 		mfd_remove_devices(&dev->dev);
160 
161 	return ret;
162 }
163 
164 static void lpc_sch_remove(struct pci_dev *dev)
165 {
166 	mfd_remove_devices(&dev->dev);
167 }
168 
169 static struct pci_driver lpc_sch_driver = {
170 	.name		= "lpc_sch",
171 	.id_table	= lpc_sch_ids,
172 	.probe		= lpc_sch_probe,
173 	.remove		= lpc_sch_remove,
174 };
175 
176 module_pci_driver(lpc_sch_driver);
177 
178 MODULE_AUTHOR("Denis Turischev <denis@compulab.co.il>");
179 MODULE_DESCRIPTION("LPC interface for Intel Poulsbo SCH");
180 MODULE_LICENSE("GPL");
181