xref: /openbmc/linux/drivers/mfd/lpc_sch.c (revision 293d5b43)
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  *  Copyright (c) 2014 Intel Corp.
11  *  Author: Denis Turischev <denis@compulab.co.il>
12  *
13  *  This program is free software; you can redistribute it and/or modify
14  *  it under the terms of the GNU General Public License 2 as published
15  *  by the Free Software Foundation.
16  *
17  *  This program is distributed in the hope that it will be useful,
18  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
19  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  *  GNU General Public License for more details.
21  */
22 
23 #include <linux/kernel.h>
24 #include <linux/module.h>
25 #include <linux/errno.h>
26 #include <linux/acpi.h>
27 #include <linux/pci.h>
28 #include <linux/mfd/core.h>
29 
30 #define SMBASE		0x40
31 #define SMBUS_IO_SIZE	64
32 
33 #define GPIOBASE	0x44
34 #define GPIO_IO_SIZE	64
35 #define GPIO_IO_SIZE_CENTERTON	128
36 
37 /* Intel Quark X1000 GPIO IRQ Number */
38 #define GPIO_IRQ_QUARK_X1000	9
39 
40 #define WDTBASE		0x84
41 #define WDT_IO_SIZE	64
42 
43 enum sch_chipsets {
44 	LPC_SCH = 0,		/* Intel Poulsbo SCH */
45 	LPC_ITC,		/* Intel Tunnel Creek */
46 	LPC_CENTERTON,		/* Intel Centerton */
47 	LPC_QUARK_X1000,	/* Intel Quark X1000 */
48 };
49 
50 struct lpc_sch_info {
51 	unsigned int io_size_smbus;
52 	unsigned int io_size_gpio;
53 	unsigned int io_size_wdt;
54 	int irq_gpio;
55 };
56 
57 static struct lpc_sch_info sch_chipset_info[] = {
58 	[LPC_SCH] = {
59 		.io_size_smbus = SMBUS_IO_SIZE,
60 		.io_size_gpio = GPIO_IO_SIZE,
61 		.irq_gpio = -1,
62 	},
63 	[LPC_ITC] = {
64 		.io_size_smbus = SMBUS_IO_SIZE,
65 		.io_size_gpio = GPIO_IO_SIZE,
66 		.io_size_wdt = WDT_IO_SIZE,
67 		.irq_gpio = -1,
68 	},
69 	[LPC_CENTERTON] = {
70 		.io_size_smbus = SMBUS_IO_SIZE,
71 		.io_size_gpio = GPIO_IO_SIZE_CENTERTON,
72 		.io_size_wdt = WDT_IO_SIZE,
73 		.irq_gpio = -1,
74 	},
75 	[LPC_QUARK_X1000] = {
76 		.io_size_gpio = GPIO_IO_SIZE,
77 		.irq_gpio = GPIO_IRQ_QUARK_X1000,
78 		.io_size_wdt = WDT_IO_SIZE,
79 	},
80 };
81 
82 static const struct pci_device_id lpc_sch_ids[] = {
83 	{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_SCH_LPC), LPC_SCH },
84 	{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ITC_LPC), LPC_ITC },
85 	{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_CENTERTON_ILB), LPC_CENTERTON },
86 	{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_QUARK_X1000_ILB), LPC_QUARK_X1000 },
87 	{ 0, }
88 };
89 MODULE_DEVICE_TABLE(pci, lpc_sch_ids);
90 
91 #define LPC_NO_RESOURCE		1
92 #define LPC_SKIP_RESOURCE	2
93 
94 static int lpc_sch_get_io(struct pci_dev *pdev, int where, const char *name,
95 			  struct resource *res, int size)
96 {
97 	unsigned int base_addr_cfg;
98 	unsigned short base_addr;
99 
100 	if (size == 0)
101 		return LPC_NO_RESOURCE;
102 
103 	pci_read_config_dword(pdev, where, &base_addr_cfg);
104 	base_addr = 0;
105 	if (!(base_addr_cfg & (1 << 31)))
106 		dev_warn(&pdev->dev, "Decode of the %s I/O range disabled\n",
107 			 name);
108 	else
109 		base_addr = (unsigned short)base_addr_cfg;
110 
111 	if (base_addr == 0) {
112 		dev_warn(&pdev->dev, "I/O space for %s uninitialized\n", name);
113 		return LPC_SKIP_RESOURCE;
114 	}
115 
116 	res->start = base_addr;
117 	res->end = base_addr + size - 1;
118 	res->flags = IORESOURCE_IO;
119 
120 	return 0;
121 }
122 
123 static int lpc_sch_populate_cell(struct pci_dev *pdev, int where,
124 				 const char *name, int size, int irq,
125 				 int id, struct mfd_cell *cell)
126 {
127 	struct resource *res;
128 	int ret;
129 
130 	res = devm_kcalloc(&pdev->dev, 2, sizeof(*res), GFP_KERNEL);
131 	if (!res)
132 		return -ENOMEM;
133 
134 	ret = lpc_sch_get_io(pdev, where, name, res, size);
135 	if (ret)
136 		return ret;
137 
138 	memset(cell, 0, sizeof(*cell));
139 
140 	cell->name = name;
141 	cell->resources = res;
142 	cell->num_resources = 1;
143 	cell->ignore_resource_conflicts = true;
144 	cell->id = id;
145 
146 	/* Check if we need to add an IRQ resource */
147 	if (irq < 0)
148 		return 0;
149 
150 	res++;
151 
152 	res->start = irq;
153 	res->end = irq;
154 	res->flags = IORESOURCE_IRQ;
155 
156 	cell->num_resources++;
157 
158 	return 0;
159 }
160 
161 static int lpc_sch_probe(struct pci_dev *dev, const struct pci_device_id *id)
162 {
163 	struct mfd_cell lpc_sch_cells[3];
164 	struct lpc_sch_info *info = &sch_chipset_info[id->driver_data];
165 	unsigned int cells = 0;
166 	int ret;
167 
168 	ret = lpc_sch_populate_cell(dev, SMBASE, "isch_smbus",
169 				    info->io_size_smbus, -1,
170 				    id->device, &lpc_sch_cells[cells]);
171 	if (ret < 0)
172 		return ret;
173 	if (ret == 0)
174 		cells++;
175 
176 	ret = lpc_sch_populate_cell(dev, GPIOBASE, "sch_gpio",
177 				    info->io_size_gpio, info->irq_gpio,
178 				    id->device, &lpc_sch_cells[cells]);
179 	if (ret < 0)
180 		return ret;
181 	if (ret == 0)
182 		cells++;
183 
184 	ret = lpc_sch_populate_cell(dev, WDTBASE, "ie6xx_wdt",
185 				    info->io_size_wdt, -1,
186 				    id->device, &lpc_sch_cells[cells]);
187 	if (ret < 0)
188 		return ret;
189 	if (ret == 0)
190 		cells++;
191 
192 	if (cells == 0) {
193 		dev_err(&dev->dev, "All decode registers disabled.\n");
194 		return -ENODEV;
195 	}
196 
197 	return mfd_add_devices(&dev->dev, 0, lpc_sch_cells, cells, NULL, 0, NULL);
198 }
199 
200 static void lpc_sch_remove(struct pci_dev *dev)
201 {
202 	mfd_remove_devices(&dev->dev);
203 }
204 
205 static struct pci_driver lpc_sch_driver = {
206 	.name		= "lpc_sch",
207 	.id_table	= lpc_sch_ids,
208 	.probe		= lpc_sch_probe,
209 	.remove		= lpc_sch_remove,
210 };
211 
212 module_pci_driver(lpc_sch_driver);
213 
214 MODULE_AUTHOR("Denis Turischev <denis@compulab.co.il>");
215 MODULE_DESCRIPTION("LPC interface for Intel Poulsbo SCH");
216 MODULE_LICENSE("GPL");
217