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 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
  35 enum 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
  42 struct 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
  49 static 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
  74 static 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 };
  81 MODULE_DEVICE_TABLE(pci, lpc_sch_ids);
  82
  83 #define LPC_NO_RESOURCE         1
  84 #define LPC_SKIP_RESOURCE       2
  85
  86 static 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
 115 static 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
 153 static 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
 192 static void lpc_sch_remove(struct pci_dev *dev)
 193 {
 194         mfd_remove_devices(&dev->dev);
 195 }
 196
 197 static 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
 204 module_pci_driver(lpc_sch_driver);
 205
 206 MODULE_AUTHOR("Denis Turischev <denis@compulab.co.il>");
 207 MODULE_DESCRIPTION("LPC interface for Intel Poulsbo SCH");
 208 MODULE_LICENSE("GPL");