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
32enum 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
39struct lpc_sch_info {
40 unsigned int io_size_smbus;
41 unsigned int io_size_gpio;
42 unsigned int io_size_wdt;
43};
44
45static 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
66static 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};
73MODULE_DEVICE_TABLE(pci, lpc_sch_ids);
74
75#define LPC_NO_RESOURCE 1
76#define LPC_SKIP_RESOURCE 2
77
78static 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(dev: pdev, where, val: &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
107static 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(dev: &pdev->dev, size: 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
133static 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(pdev: dev, SMBASE, name: "isch_smbus",
141 size: info->io_size_smbus,
142 id: id->device, cell: &lpc_sch_cells[cells]);
143 if (ret < 0)
144 return ret;
145 if (ret == 0)
146 cells++;
147
148 ret = lpc_sch_populate_cell(pdev: dev, GPIO_BASE, name: "sch_gpio",
149 size: info->io_size_gpio,
150 id: id->device, cell: &lpc_sch_cells[cells]);
151 if (ret < 0)
152 return ret;
153 if (ret == 0)
154 cells++;
155
156 ret = lpc_sch_populate_cell(pdev: dev, WDTBASE, name: "ie6xx_wdt",
157 size: info->io_size_wdt,
158 id: id->device, cell: &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(parent: &dev->dev, id: 0, cells: lpc_sch_cells, n_devs: cells, NULL, irq_base: 0, NULL);
170}
171
172static void lpc_sch_remove(struct pci_dev *dev)
173{
174 mfd_remove_devices(parent: &dev->dev);
175}
176
177static 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
184module_pci_driver(lpc_sch_driver);
185
186MODULE_AUTHOR("Denis Turischev <denis@compulab.co.il>");
187MODULE_DESCRIPTION("LPC interface for Intel Poulsbo SCH");
188MODULE_LICENSE("GPL");
189

source code of linux/drivers/mfd/lpc_sch.c