xref: /linux/drivers/mfd/lpc_sch.c (revision f884ab15afdc5514e88105c92a4e2e1e6539869a)
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 #define GPIO_IO_SIZE_CENTERTON	128
40 
41 #define WDTBASE		0x84
42 #define WDT_IO_SIZE	64
43 
44 static struct resource smbus_sch_resource = {
45 		.flags = IORESOURCE_IO,
46 };
47 
48 static struct resource gpio_sch_resource = {
49 		.flags = IORESOURCE_IO,
50 };
51 
52 static struct resource wdt_sch_resource = {
53 		.flags = IORESOURCE_IO,
54 };
55 
56 static struct mfd_cell lpc_sch_cells[3];
57 
58 static struct mfd_cell isch_smbus_cell = {
59 	.name = "isch_smbus",
60 	.num_resources = 1,
61 	.resources = &smbus_sch_resource,
62 };
63 
64 static struct mfd_cell sch_gpio_cell = {
65 	.name = "sch_gpio",
66 	.num_resources = 1,
67 	.resources = &gpio_sch_resource,
68 };
69 
70 static struct mfd_cell wdt_sch_cell = {
71 	.name = "ie6xx_wdt",
72 	.num_resources = 1,
73 	.resources = &wdt_sch_resource,
74 };
75 
76 static DEFINE_PCI_DEVICE_TABLE(lpc_sch_ids) = {
77 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SCH_LPC) },
78 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ITC_LPC) },
79 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_CENTERTON_ILB) },
80 	{ 0, }
81 };
82 MODULE_DEVICE_TABLE(pci, lpc_sch_ids);
83 
84 static int lpc_sch_probe(struct pci_dev *dev,
85 				const struct pci_device_id *id)
86 {
87 	unsigned int base_addr_cfg;
88 	unsigned short base_addr;
89 	int i, cells = 0;
90 	int ret;
91 
92 	pci_read_config_dword(dev, SMBASE, &base_addr_cfg);
93 	base_addr = 0;
94 	if (!(base_addr_cfg & (1 << 31)))
95 		dev_warn(&dev->dev, "Decode of the SMBus I/O range disabled\n");
96 	else
97 		base_addr = (unsigned short)base_addr_cfg;
98 
99 	if (base_addr == 0) {
100 		dev_warn(&dev->dev, "I/O space for SMBus uninitialized\n");
101 	} else {
102 		lpc_sch_cells[cells++] = isch_smbus_cell;
103 		smbus_sch_resource.start = base_addr;
104 		smbus_sch_resource.end = base_addr + SMBUS_IO_SIZE - 1;
105 	}
106 
107 	pci_read_config_dword(dev, GPIOBASE, &base_addr_cfg);
108 	base_addr = 0;
109 	if (!(base_addr_cfg & (1 << 31)))
110 		dev_warn(&dev->dev, "Decode of the GPIO I/O range disabled\n");
111 	else
112 		base_addr = (unsigned short)base_addr_cfg;
113 
114 	if (base_addr == 0) {
115 		dev_warn(&dev->dev, "I/O space for GPIO uninitialized\n");
116 	} else {
117 		lpc_sch_cells[cells++] = sch_gpio_cell;
118 		gpio_sch_resource.start = base_addr;
119 		if (id->device == PCI_DEVICE_ID_INTEL_CENTERTON_ILB)
120 			gpio_sch_resource.end = base_addr + GPIO_IO_SIZE_CENTERTON - 1;
121 		else
122 			gpio_sch_resource.end = base_addr + GPIO_IO_SIZE - 1;
123 	}
124 
125 	if (id->device == PCI_DEVICE_ID_INTEL_ITC_LPC
126 	    || id->device == PCI_DEVICE_ID_INTEL_CENTERTON_ILB) {
127 		pci_read_config_dword(dev, WDTBASE, &base_addr_cfg);
128 		base_addr = 0;
129 		if (!(base_addr_cfg & (1 << 31)))
130 			dev_warn(&dev->dev, "Decode of the WDT I/O range disabled\n");
131 		else
132 			base_addr = (unsigned short)base_addr_cfg;
133 		if (base_addr == 0)
134 			dev_warn(&dev->dev, "I/O space for WDT uninitialized\n");
135 		else {
136 			lpc_sch_cells[cells++] = wdt_sch_cell;
137 			wdt_sch_resource.start = base_addr;
138 			wdt_sch_resource.end = base_addr + WDT_IO_SIZE - 1;
139 		}
140 	}
141 
142 	if (WARN_ON(cells > ARRAY_SIZE(lpc_sch_cells))) {
143 		dev_err(&dev->dev, "Cell count exceeds array size");
144 		return -ENODEV;
145 	}
146 
147 	if (cells == 0) {
148 		dev_err(&dev->dev, "All decode registers disabled.\n");
149 		return -ENODEV;
150 	}
151 
152 	for (i = 0; i < cells; i++)
153 		lpc_sch_cells[i].id = id->device;
154 
155 	ret = mfd_add_devices(&dev->dev, 0, lpc_sch_cells, cells, NULL, 0, NULL);
156 	if (ret)
157 		mfd_remove_devices(&dev->dev);
158 
159 	return ret;
160 }
161 
162 static void lpc_sch_remove(struct pci_dev *dev)
163 {
164 	mfd_remove_devices(&dev->dev);
165 }
166 
167 static struct pci_driver lpc_sch_driver = {
168 	.name		= "lpc_sch",
169 	.id_table	= lpc_sch_ids,
170 	.probe		= lpc_sch_probe,
171 	.remove		= lpc_sch_remove,
172 };
173 
174 module_pci_driver(lpc_sch_driver);
175 
176 MODULE_AUTHOR("Denis Turischev <denis@compulab.co.il>");
177 MODULE_DESCRIPTION("LPC interface for Intel Poulsbo SCH");
178 MODULE_LICENSE("GPL");
179