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 GPIOBASE        0x44
  26#define GPIO_IO_SIZE    64
  27#define GPIO_IO_SIZE_CENTERTON  128
  28
  29/* Intel Quark X1000 GPIO IRQ Number */
  30#define GPIO_IRQ_QUARK_X1000    9
  31
  32#define WDTBASE         0x84
  33#define WDT_IO_SIZE     64
  34
  35enum sch_chipsets {
  36        LPC_SCH = 0,            /* Intel Poulsbo SCH */
  37        LPC_ITC,                /* Intel Tunnel Creek */
  38        LPC_CENTERTON,          /* Intel Centerton */
  39        LPC_QUARK_X1000,        /* Intel Quark X1000 */
  40};
  41
  42struct lpc_sch_info {
  43        unsigned int io_size_smbus;
  44        unsigned int io_size_gpio;
  45        unsigned int io_size_wdt;
  46        int irq_gpio;
  47};
  48
  49static struct lpc_sch_info sch_chipset_info[] = {
  50        [LPC_SCH] = {
  51                .io_size_smbus = SMBUS_IO_SIZE,
  52                .io_size_gpio = GPIO_IO_SIZE,
  53                .irq_gpio = -1,
  54        },
  55        [LPC_ITC] = {
  56                .io_size_smbus = SMBUS_IO_SIZE,
  57                .io_size_gpio = GPIO_IO_SIZE,
  58                .io_size_wdt = WDT_IO_SIZE,
  59                .irq_gpio = -1,
  60        },
  61        [LPC_CENTERTON] = {
  62                .io_size_smbus = SMBUS_IO_SIZE,
  63                .io_size_gpio = GPIO_IO_SIZE_CENTERTON,
  64                .io_size_wdt = WDT_IO_SIZE,
  65                .irq_gpio = -1,
  66        },
  67        [LPC_QUARK_X1000] = {
  68                .io_size_gpio = GPIO_IO_SIZE,
  69                .irq_gpio = GPIO_IRQ_QUARK_X1000,
  70                .io_size_wdt = WDT_IO_SIZE,
  71        },
  72};
  73
  74static const struct pci_device_id lpc_sch_ids[] = {
  75        { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_SCH_LPC), LPC_SCH },
  76        { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_ITC_LPC), LPC_ITC },
  77        { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_CENTERTON_ILB), LPC_CENTERTON },
  78        { PCI_VDEVICE(INTEL, PCI_DEVICE_ID_INTEL_QUARK_X1000_ILB), LPC_QUARK_X1000 },
  79        { 0, }
  80};
  81MODULE_DEVICE_TABLE(pci, lpc_sch_ids);
  82
  83#define LPC_NO_RESOURCE         1
  84#define LPC_SKIP_RESOURCE       2
  85
  86static int lpc_sch_get_io(struct pci_dev *pdev, int where, const char *name,
  87                          struct resource *res, int size)
  88{
  89        unsigned int base_addr_cfg;
  90        unsigned short base_addr;
  91
  92        if (size == 0)
  93                return LPC_NO_RESOURCE;
  94
  95        pci_read_config_dword(pdev, where, &base_addr_cfg);
  96        base_addr = 0;
  97        if (!(base_addr_cfg & (1 << 31)))
  98                dev_warn(&pdev->dev, "Decode of the %s I/O range disabled\n",
  99                         name);
 100        else
 101                base_addr = (unsigned short)base_addr_cfg;
 102
 103        if (base_addr == 0) {
 104                dev_warn(&pdev->dev, "I/O space for %s uninitialized\n", name);
 105                return LPC_SKIP_RESOURCE;
 106        }
 107
 108        res->start = base_addr;
 109        res->end = base_addr + size - 1;
 110        res->flags = IORESOURCE_IO;
 111
 112        return 0;
 113}
 114
 115static int lpc_sch_populate_cell(struct pci_dev *pdev, int where,
 116                                 const char *name, int size, int irq,
 117                                 int id, struct mfd_cell *cell)
 118{
 119        struct resource *res;
 120        int ret;
 121
 122        res = devm_kcalloc(&pdev->dev, 2, sizeof(*res), GFP_KERNEL);
 123        if (!res)
 124                return -ENOMEM;
 125
 126        ret = lpc_sch_get_io(pdev, where, name, res, size);
 127        if (ret)
 128                return ret;
 129
 130        memset(cell, 0, sizeof(*cell));
 131
 132        cell->name = name;
 133        cell->resources = res;
 134        cell->num_resources = 1;
 135        cell->ignore_resource_conflicts = true;
 136        cell->id = id;
 137
 138        /* Check if we need to add an IRQ resource */
 139        if (irq < 0)
 140                return 0;
 141
 142        res++;
 143
 144        res->start = irq;
 145        res->end = irq;
 146        res->flags = IORESOURCE_IRQ;
 147
 148        cell->num_resources++;
 149
 150        return 0;
 151}
 152
 153static int lpc_sch_probe(struct pci_dev *dev, const struct pci_device_id *id)
 154{
 155        struct mfd_cell lpc_sch_cells[3];
 156        struct lpc_sch_info *info = &sch_chipset_info[id->driver_data];
 157        unsigned int cells = 0;
 158        int ret;
 159
 160        ret = lpc_sch_populate_cell(dev, SMBASE, "isch_smbus",
 161                                    info->io_size_smbus, -1,
 162                                    id->device, &lpc_sch_cells[cells]);
 163        if (ret < 0)
 164                return ret;
 165        if (ret == 0)
 166                cells++;
 167
 168        ret = lpc_sch_populate_cell(dev, GPIOBASE, "sch_gpio",
 169                                    info->io_size_gpio, info->irq_gpio,
 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, WDTBASE, "ie6xx_wdt",
 177                                    info->io_size_wdt, -1,
 178                                    id->device, &lpc_sch_cells[cells]);
 179        if (ret < 0)
 180                return ret;
 181        if (ret == 0)
 182                cells++;
 183
 184        if (cells == 0) {
 185                dev_err(&dev->dev, "All decode registers disabled.\n");
 186                return -ENODEV;
 187        }
 188
 189        return mfd_add_devices(&dev->dev, 0, lpc_sch_cells, cells, NULL, 0, NULL);
 190}
 191
 192static void lpc_sch_remove(struct pci_dev *dev)
 193{
 194        mfd_remove_devices(&dev->dev);
 195}
 196
 197static struct pci_driver lpc_sch_driver = {
 198        .name           = "lpc_sch",
 199        .id_table       = lpc_sch_ids,
 200        .probe          = lpc_sch_probe,
 201        .remove         = lpc_sch_remove,
 202};
 203
 204module_pci_driver(lpc_sch_driver);
 205
 206MODULE_AUTHOR("Denis Turischev <denis@compulab.co.il>");
 207MODULE_DESCRIPTION("LPC interface for Intel Poulsbo SCH");
 208MODULE_LICENSE("GPL");
 209