linux/drivers/mfd/lpc_sch.c
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   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(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
 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(&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
 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(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
 172static void lpc_sch_remove(struct pci_dev *dev)
 173{
 174        mfd_remove_devices(&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