xref: /openbmc/linux/drivers/mfd/lpc_sch.c (revision 8684014d)
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 	},
79 };
80 
81 static const struct pci_device_id lpc_sch_ids[] = {
82 	{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_SCH_LPC), LPC_SCH },
83 	{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ITC_LPC), LPC_ITC },
84 	{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_CENTERTON_ILB), LPC_CENTERTON },
85 	{ PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_QUARK_X1000_ILB), LPC_QUARK_X1000 },
86 	{ 0, }
87 };
88 MODULE_DEVICE_TABLE(pci, lpc_sch_ids);
89 
90 #define LPC_NO_RESOURCE		1
91 #define LPC_SKIP_RESOURCE	2
92 
93 static int lpc_sch_get_io(struct pci_dev *pdev, int where, const char *name,
94 			  struct resource *res, int size)
95 {
96 	unsigned int base_addr_cfg;
97 	unsigned short base_addr;
98 
99 	if (size == 0)
100 		return LPC_NO_RESOURCE;
101 
102 	pci_read_config_dword(pdev, where, &base_addr_cfg);
103 	base_addr = 0;
104 	if (!(base_addr_cfg & (1 << 31)))
105 		dev_warn(&pdev->dev, "Decode of the %s I/O range disabled\n",
106 			 name);
107 	else
108 		base_addr = (unsigned short)base_addr_cfg;
109 
110 	if (base_addr == 0) {
111 		dev_warn(&pdev->dev, "I/O space for %s uninitialized\n", name);
112 		return LPC_SKIP_RESOURCE;
113 	}
114 
115 	res->start = base_addr;
116 	res->end = base_addr + size - 1;
117 	res->flags = IORESOURCE_IO;
118 
119 	return 0;
120 }
121 
122 static int lpc_sch_populate_cell(struct pci_dev *pdev, int where,
123 				 const char *name, int size, int irq,
124 				 int id, struct mfd_cell *cell)
125 {
126 	struct resource *res;
127 	int ret;
128 
129 	res = devm_kcalloc(&pdev->dev, 2, sizeof(*res), GFP_KERNEL);
130 	if (!res)
131 		return -ENOMEM;
132 
133 	ret = lpc_sch_get_io(pdev, where, name, res, size);
134 	if (ret)
135 		return ret;
136 
137 	memset(cell, 0, sizeof(*cell));
138 
139 	cell->name = name;
140 	cell->resources = res;
141 	cell->num_resources = 1;
142 	cell->ignore_resource_conflicts = true;
143 	cell->id = id;
144 
145 	/* Check if we need to add an IRQ resource */
146 	if (irq < 0)
147 		return 0;
148 
149 	res++;
150 
151 	res->start = irq;
152 	res->end = irq;
153 	res->flags = IORESOURCE_IRQ;
154 
155 	cell->num_resources++;
156 
157 	return 0;
158 }
159 
160 static int lpc_sch_probe(struct pci_dev *dev, const struct pci_device_id *id)
161 {
162 	struct mfd_cell lpc_sch_cells[3];
163 	struct lpc_sch_info *info = &sch_chipset_info[id->driver_data];
164 	unsigned int cells = 0;
165 	int ret;
166 
167 	ret = lpc_sch_populate_cell(dev, SMBASE, "isch_smbus",
168 				    info->io_size_smbus, -1,
169 				    id->device, &lpc_sch_cells[cells]);
170 	if (ret < 0)
171 		return ret;
172 	if (ret == 0)
173 		cells++;
174 
175 	ret = lpc_sch_populate_cell(dev, GPIOBASE, "sch_gpio",
176 				    info->io_size_gpio, info->irq_gpio,
177 				    id->device, &lpc_sch_cells[cells]);
178 	if (ret < 0)
179 		return ret;
180 	if (ret == 0)
181 		cells++;
182 
183 	ret = lpc_sch_populate_cell(dev, WDTBASE, "ie6xx_wdt",
184 				    info->io_size_wdt, -1,
185 				    id->device, &lpc_sch_cells[cells]);
186 	if (ret < 0)
187 		return ret;
188 	if (ret == 0)
189 		cells++;
190 
191 	if (cells == 0) {
192 		dev_err(&dev->dev, "All decode registers disabled.\n");
193 		return -ENODEV;
194 	}
195 
196 	return mfd_add_devices(&dev->dev, 0, lpc_sch_cells, cells, NULL, 0, NULL);
197 }
198 
199 static void lpc_sch_remove(struct pci_dev *dev)
200 {
201 	mfd_remove_devices(&dev->dev);
202 }
203 
204 static struct pci_driver lpc_sch_driver = {
205 	.name		= "lpc_sch",
206 	.id_table	= lpc_sch_ids,
207 	.probe		= lpc_sch_probe,
208 	.remove		= lpc_sch_remove,
209 };
210 
211 module_pci_driver(lpc_sch_driver);
212 
213 MODULE_AUTHOR("Denis Turischev <denis@compulab.co.il>");
214 MODULE_DESCRIPTION("LPC interface for Intel Poulsbo SCH");
215 MODULE_LICENSE("GPL");
216