1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * lpc_sch.c - LPC interface for Intel Poulsbo SCH
4 *
5 * LPC bridge function of the Intel SCH contains many other
6 * functional units, such as Interrupt controllers, Timers,
7 * Power Management, System Management, GPIO, RTC, and LPC
8 * Configuration Registers.
9 *
10 * Copyright (c) 2010 CompuLab Ltd
11 * Copyright (c) 2014 Intel Corp.
12 * Author: Denis Turischev <denis@compulab.co.il>
13 */
14
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/errno.h>
18 #include <linux/acpi.h>
19 #include <linux/pci.h>
20 #include <linux/mfd/core.h>
21
22 #define SMBASE 0x40
23 #define SMBUS_IO_SIZE 64
24
25 #define GPIO_BASE 0x44
26 #define GPIO_IO_SIZE 64
27 #define GPIO_IO_SIZE_CENTERTON 128
28
29 #define WDTBASE 0x84
30 #define WDT_IO_SIZE 64
31
32 enum sch_chipsets {
33 LPC_SCH = 0, /* Intel Poulsbo SCH */
34 LPC_ITC, /* Intel Tunnel Creek */
35 LPC_CENTERTON, /* Intel Centerton */
36 LPC_QUARK_X1000, /* Intel Quark X1000 */
37 };
38
39 struct lpc_sch_info {
40 unsigned int io_size_smbus;
41 unsigned int io_size_gpio;
42 unsigned int io_size_wdt;
43 };
44
45 static struct lpc_sch_info sch_chipset_info[] = {
46 [LPC_SCH] = {
47 .io_size_smbus = SMBUS_IO_SIZE,
48 .io_size_gpio = GPIO_IO_SIZE,
49 },
50 [LPC_ITC] = {
51 .io_size_smbus = SMBUS_IO_SIZE,
52 .io_size_gpio = GPIO_IO_SIZE,
53 .io_size_wdt = WDT_IO_SIZE,
54 },
55 [LPC_CENTERTON] = {
56 .io_size_smbus = SMBUS_IO_SIZE,
57 .io_size_gpio = GPIO_IO_SIZE_CENTERTON,
58 .io_size_wdt = WDT_IO_SIZE,
59 },
60 [LPC_QUARK_X1000] = {
61 .io_size_gpio = GPIO_IO_SIZE,
62 .io_size_wdt = WDT_IO_SIZE,
63 },
64 };
65
66 static const struct pci_device_id lpc_sch_ids[] = {
67 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_SCH_LPC), LPC_SCH },
68 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ITC_LPC), LPC_ITC },
69 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_CENTERTON_ILB), LPC_CENTERTON },
70 { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_QUARK_X1000_ILB), LPC_QUARK_X1000 },
71 { 0, }
72 };
73 MODULE_DEVICE_TABLE(pci, lpc_sch_ids);
74
75 #define LPC_NO_RESOURCE 1
76 #define LPC_SKIP_RESOURCE 2
77
lpc_sch_get_io(struct pci_dev * pdev,int where,const char * name,struct resource * res,int size)78 static int lpc_sch_get_io(struct pci_dev *pdev, int where, const char *name,
79 struct resource *res, int size)
80 {
81 unsigned int base_addr_cfg;
82 unsigned short base_addr;
83
84 if (size == 0)
85 return LPC_NO_RESOURCE;
86
87 pci_read_config_dword(pdev, where, &base_addr_cfg);
88 base_addr = 0;
89 if (!(base_addr_cfg & (1 << 31)))
90 dev_warn(&pdev->dev, "Decode of the %s I/O range disabled\n",
91 name);
92 else
93 base_addr = (unsigned short)base_addr_cfg;
94
95 if (base_addr == 0) {
96 dev_warn(&pdev->dev, "I/O space for %s uninitialized\n", name);
97 return LPC_SKIP_RESOURCE;
98 }
99
100 res->start = base_addr;
101 res->end = base_addr + size - 1;
102 res->flags = IORESOURCE_IO;
103
104 return 0;
105 }
106
lpc_sch_populate_cell(struct pci_dev * pdev,int where,const char * name,int size,int id,struct mfd_cell * cell)107 static int lpc_sch_populate_cell(struct pci_dev *pdev, int where,
108 const char *name, int size, int id,
109 struct mfd_cell *cell)
110 {
111 struct resource *res;
112 int ret;
113
114 res = devm_kzalloc(&pdev->dev, sizeof(*res), GFP_KERNEL);
115 if (!res)
116 return -ENOMEM;
117
118 ret = lpc_sch_get_io(pdev, where, name, res, size);
119 if (ret)
120 return ret;
121
122 memset(cell, 0, sizeof(*cell));
123
124 cell->name = name;
125 cell->resources = res;
126 cell->num_resources = 1;
127 cell->ignore_resource_conflicts = true;
128 cell->id = id;
129
130 return 0;
131 }
132
lpc_sch_probe(struct pci_dev * dev,const struct pci_device_id * id)133 static int lpc_sch_probe(struct pci_dev *dev, const struct pci_device_id *id)
134 {
135 struct mfd_cell lpc_sch_cells[3];
136 struct lpc_sch_info *info = &sch_chipset_info[id->driver_data];
137 unsigned int cells = 0;
138 int ret;
139
140 ret = lpc_sch_populate_cell(dev, SMBASE, "isch_smbus",
141 info->io_size_smbus,
142 id->device, &lpc_sch_cells[cells]);
143 if (ret < 0)
144 return ret;
145 if (ret == 0)
146 cells++;
147
148 ret = lpc_sch_populate_cell(dev, GPIO_BASE, "sch_gpio",
149 info->io_size_gpio,
150 id->device, &lpc_sch_cells[cells]);
151 if (ret < 0)
152 return ret;
153 if (ret == 0)
154 cells++;
155
156 ret = lpc_sch_populate_cell(dev, WDTBASE, "ie6xx_wdt",
157 info->io_size_wdt,
158 id->device, &lpc_sch_cells[cells]);
159 if (ret < 0)
160 return ret;
161 if (ret == 0)
162 cells++;
163
164 if (cells == 0) {
165 dev_err(&dev->dev, "All decode registers disabled.\n");
166 return -ENODEV;
167 }
168
169 return mfd_add_devices(&dev->dev, 0, lpc_sch_cells, cells, NULL, 0, NULL);
170 }
171
lpc_sch_remove(struct pci_dev * dev)172 static void lpc_sch_remove(struct pci_dev *dev)
173 {
174 mfd_remove_devices(&dev->dev);
175 }
176
177 static struct pci_driver lpc_sch_driver = {
178 .name = "lpc_sch",
179 .id_table = lpc_sch_ids,
180 .probe = lpc_sch_probe,
181 .remove = lpc_sch_remove,
182 };
183
184 module_pci_driver(lpc_sch_driver);
185
186 MODULE_AUTHOR("Denis Turischev <denis@compulab.co.il>");
187 MODULE_DESCRIPTION("LPC interface for Intel Poulsbo SCH");
188 MODULE_LICENSE("GPL");
189