drivers/mfd/lpc_sch.c

   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
  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
 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
 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
 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");