drivers/misc/cb710/core.c

   1 /*
   2  *  cb710/core.c
   3  *
   4  *  Copyright by Michał Mirosław, 2008-2009
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10 #include <linux/kernel.h>
  11 #include <linux/module.h>
  12 #include <linux/pci.h>
  13 #include <linux/spinlock.h>
  14 #include <linux/idr.h>
  15 #include <linux/cb710.h>
  16 #include <linux/gfp.h>
  17
  18 static DEFINE_IDA(cb710_ida);
  19
  20 void cb710_pci_update_config_reg(struct pci_dev *pdev,
  21         int reg, uint32_t mask, uint32_t xor)
  22 {
  23         u32 rval;
  24
  25         pci_read_config_dword(pdev, reg, &rval);
  26         rval = (rval & mask) ^ xor;
  27         pci_write_config_dword(pdev, reg, rval);
  28 }
  29 EXPORT_SYMBOL_GPL(cb710_pci_update_config_reg);
  30
  31 /* Some magic writes based on Windows driver init code */
  32 static int cb710_pci_configure(struct pci_dev *pdev)
  33 {
  34         unsigned int devfn = PCI_DEVFN(PCI_SLOT(pdev->devfn), 0);
  35         struct pci_dev *pdev0;
  36         u32 val;
  37
  38         cb710_pci_update_config_reg(pdev, 0x48,
  39                 ~0x000000FF, 0x0000003F);
  40
  41         pci_read_config_dword(pdev, 0x48, &val);
  42         if (val & 0x80000000)
  43                 return 0;
  44
  45         pdev0 = pci_get_slot(pdev->bus, devfn);
  46         if (!pdev0)
  47                 return -ENODEV;
  48
  49         if (pdev0->vendor == PCI_VENDOR_ID_ENE
  50             && pdev0->device == PCI_DEVICE_ID_ENE_720) {
  51                 cb710_pci_update_config_reg(pdev0, 0x8C,
  52                         ~0x00F00000, 0x00100000);
  53                 cb710_pci_update_config_reg(pdev0, 0xB0,
  54                         ~0x08000000, 0x08000000);
  55         }
  56
  57         cb710_pci_update_config_reg(pdev0, 0x8C,
  58                 ~0x00000F00, 0x00000200);
  59         cb710_pci_update_config_reg(pdev0, 0x90,
  60                 ~0x00060000, 0x00040000);
  61
  62         pci_dev_put(pdev0);
  63
  64         return 0;
  65 }
  66
  67 static irqreturn_t cb710_irq_handler(int irq, void *data)
  68 {
  69         struct cb710_chip *chip = data;
  70         struct cb710_slot *slot = &chip->slot[0];
  71         irqreturn_t handled = IRQ_NONE;
  72         unsigned nr;
  73
  74         spin_lock(&chip->irq_lock); /* incl. smp_rmb() */
  75
  76         for (nr = chip->slots; nr; ++slot, --nr) {
  77                 cb710_irq_handler_t handler_func = slot->irq_handler;
  78                 if (handler_func && handler_func(slot))
  79                         handled = IRQ_HANDLED;
  80         }
  81
  82         spin_unlock(&chip->irq_lock);
  83
  84         return handled;
  85 }
  86
  87 static void cb710_release_slot(struct device *dev)
  88 {
  89 #ifdef CONFIG_CB710_DEBUG_ASSUMPTIONS
  90         struct cb710_slot *slot = cb710_pdev_to_slot(to_platform_device(dev));
  91         struct cb710_chip *chip = cb710_slot_to_chip(slot);
  92
  93         /* slot struct can be freed now */
  94         atomic_dec(&chip->slot_refs_count);
  95 #endif
  96 }
  97
  98 static int cb710_register_slot(struct cb710_chip *chip,
  99         unsigned slot_mask, unsigned io_offset, const char *name)
 100 {
 101         int nr = chip->slots;
 102         struct cb710_slot *slot = &chip->slot[nr];
 103         int err;
 104
 105         dev_dbg(cb710_chip_dev(chip),
 106                 "register: %s.%d; slot %d; mask %d; IO offset: 0x%02X\n",
 107                 name, chip->platform_id, nr, slot_mask, io_offset);
 108
 109         /* slot->irq_handler == NULL here; this needs to be
 110          * seen before platform_device_register() */
 111         ++chip->slots;
 112         smp_wmb();
 113
 114         slot->iobase = chip->iobase + io_offset;
 115         slot->pdev.name = name;
 116         slot->pdev.id = chip->platform_id;
 117         slot->pdev.dev.parent = &chip->pdev->dev;
 118         slot->pdev.dev.release = cb710_release_slot;
 119
 120         err = platform_device_register(&slot->pdev);
 121
 122 #ifdef CONFIG_CB710_DEBUG_ASSUMPTIONS
 123         atomic_inc(&chip->slot_refs_count);
 124 #endif
 125
 126         if (err) {
 127                 /* device_initialize() called from platform_device_register()
 128                  * wants this on error path */
 129                 platform_device_put(&slot->pdev);
 130
 131                 /* slot->irq_handler == NULL here anyway, so no lock needed */
 132                 --chip->slots;
 133                 return err;
 134         }
 135
 136         chip->slot_mask |= slot_mask;
 137
 138         return 0;
 139 }
 140
 141 static void cb710_unregister_slot(struct cb710_chip *chip,
 142         unsigned slot_mask)
 143 {
 144         int nr = chip->slots - 1;
 145
 146         if (!(chip->slot_mask & slot_mask))
 147                 return;
 148
 149         platform_device_unregister(&chip->slot[nr].pdev);
 150
 151         /* complementary to spin_unlock() in cb710_set_irq_handler() */
 152         smp_rmb();
 153         BUG_ON(chip->slot[nr].irq_handler != NULL);
 154
 155         /* slot->irq_handler == NULL here, so no lock needed */
 156         --chip->slots;
 157         chip->slot_mask &= ~slot_mask;
 158 }
 159
 160 void cb710_set_irq_handler(struct cb710_slot *slot,
 161         cb710_irq_handler_t handler)
 162 {
 163         struct cb710_chip *chip = cb710_slot_to_chip(slot);
 164         unsigned long flags;
 165
 166         spin_lock_irqsave(&chip->irq_lock, flags);
 167         slot->irq_handler = handler;
 168         spin_unlock_irqrestore(&chip->irq_lock, flags);
 169 }
 170 EXPORT_SYMBOL_GPL(cb710_set_irq_handler);
 171
 172 #ifdef CONFIG_PM
 173
 174 static int cb710_suspend(struct pci_dev *pdev, pm_message_t state)
 175 {
 176         struct cb710_chip *chip = pci_get_drvdata(pdev);
 177
 178         devm_free_irq(&pdev->dev, pdev->irq, chip);
 179         pci_save_state(pdev);
 180         pci_disable_device(pdev);
 181         if (state.event & PM_EVENT_SLEEP)
 182                 pci_set_power_state(pdev, PCI_D3hot);
 183         return 0;
 184 }
 185
 186 static int cb710_resume(struct pci_dev *pdev)
 187 {
 188         struct cb710_chip *chip = pci_get_drvdata(pdev);
 189         int err;
 190
 191         pci_set_power_state(pdev, PCI_D0);
 192         pci_restore_state(pdev);
 193         err = pcim_enable_device(pdev);
 194         if (err)
 195                 return err;
 196
 197         return devm_request_irq(&pdev->dev, pdev->irq,
 198                 cb710_irq_handler, IRQF_SHARED, KBUILD_MODNAME, chip);
 199 }
 200
 201 #endif /* CONFIG_PM */
 202
 203 static int cb710_probe(struct pci_dev *pdev,
 204         const struct pci_device_id *ent)
 205 {
 206         struct cb710_chip *chip;
 207         u32 val;
 208         int err;
 209         int n = 0;
 210
 211         err = cb710_pci_configure(pdev);
 212         if (err)
 213                 return err;
 214
 215         /* this is actually magic... */
 216         pci_read_config_dword(pdev, 0x48, &val);
 217         if (!(val & 0x80000000)) {
 218                 pci_write_config_dword(pdev, 0x48, val|0x71000000);
 219                 pci_read_config_dword(pdev, 0x48, &val);
 220         }
 221
 222         dev_dbg(&pdev->dev, "PCI config[0x48] = 0x%08X\n", val);
 223         if (!(val & 0x70000000))
 224                 return -ENODEV;
 225         val = (val >> 28) & 7;
 226         if (val & CB710_SLOT_MMC)
 227                 ++n;
 228         if (val & CB710_SLOT_MS)
 229                 ++n;
 230         if (val & CB710_SLOT_SM)
 231                 ++n;
 232
 233         chip = devm_kzalloc(&pdev->dev, struct_size(chip, slot, n),
 234                             GFP_KERNEL);
 235         if (!chip)
 236                 return -ENOMEM;
 237
 238         err = pcim_enable_device(pdev);
 239         if (err)
 240                 return err;
 241
 242         err = pcim_iomap_regions(pdev, 0x0001, KBUILD_MODNAME);
 243         if (err)
 244                 return err;
 245
 246         spin_lock_init(&chip->irq_lock);
 247         chip->pdev = pdev;
 248         chip->iobase = pcim_iomap_table(pdev)[0];
 249
 250         pci_set_drvdata(pdev, chip);
 251
 252         err = devm_request_irq(&pdev->dev, pdev->irq,
 253                 cb710_irq_handler, IRQF_SHARED, KBUILD_MODNAME, chip);
 254         if (err)
 255                 return err;
 256
 257         err = ida_alloc(&cb710_ida, GFP_KERNEL);
 258         if (err < 0)
 259                 return err;
 260         chip->platform_id = err;
 261
 262         dev_info(&pdev->dev, "id %d, IO 0x%p, IRQ %d\n",
 263                 chip->platform_id, chip->iobase, pdev->irq);
 264
 265         if (val & CB710_SLOT_MMC) {     /* MMC/SD slot */
 266                 err = cb710_register_slot(chip,
 267                         CB710_SLOT_MMC, 0x00, "cb710-mmc");
 268                 if (err)
 269                         return err;
 270         }
 271
 272         if (val & CB710_SLOT_MS) {      /* MemoryStick slot */
 273                 err = cb710_register_slot(chip,
 274                         CB710_SLOT_MS, 0x40, "cb710-ms");
 275                 if (err)
 276                         goto unreg_mmc;
 277         }
 278
 279         if (val & CB710_SLOT_SM) {      /* SmartMedia slot */
 280                 err = cb710_register_slot(chip,
 281                         CB710_SLOT_SM, 0x60, "cb710-sm");
 282                 if (err)
 283                         goto unreg_ms;
 284         }
 285
 286         return 0;
 287 unreg_ms:
 288         cb710_unregister_slot(chip, CB710_SLOT_MS);
 289 unreg_mmc:
 290         cb710_unregister_slot(chip, CB710_SLOT_MMC);
 291
 292 #ifdef CONFIG_CB710_DEBUG_ASSUMPTIONS
 293         BUG_ON(atomic_read(&chip->slot_refs_count) != 0);
 294 #endif
 295         return err;
 296 }
 297
 298 static void cb710_remove_one(struct pci_dev *pdev)
 299 {
 300         struct cb710_chip *chip = pci_get_drvdata(pdev);
 301
 302         cb710_unregister_slot(chip, CB710_SLOT_SM);
 303         cb710_unregister_slot(chip, CB710_SLOT_MS);
 304         cb710_unregister_slot(chip, CB710_SLOT_MMC);
 305 #ifdef CONFIG_CB710_DEBUG_ASSUMPTIONS
 306         BUG_ON(atomic_read(&chip->slot_refs_count) != 0);
 307 #endif
 308
 309         ida_free(&cb710_ida, chip->platform_id);
 310 }
 311
 312 static const struct pci_device_id cb710_pci_tbl[] = {
 313         { PCI_VENDOR_ID_ENE, PCI_DEVICE_ID_ENE_CB710_FLASH,
 314                 PCI_ANY_ID, PCI_ANY_ID, },
 315         { 0, }
 316 };
 317
 318 static struct pci_driver cb710_driver = {
 319         .name = KBUILD_MODNAME,
 320         .id_table = cb710_pci_tbl,
 321         .probe = cb710_probe,
 322         .remove = cb710_remove_one,
 323 #ifdef CONFIG_PM
 324         .suspend = cb710_suspend,
 325         .resume = cb710_resume,
 326 #endif
 327 };
 328
 329 static int __init cb710_init_module(void)
 330 {
 331         return pci_register_driver(&cb710_driver);
 332 }
 333
 334 static void __exit cb710_cleanup_module(void)
 335 {
 336         pci_unregister_driver(&cb710_driver);
 337         ida_destroy(&cb710_ida);
 338 }
 339
 340 module_init(cb710_init_module);
 341 module_exit(cb710_cleanup_module);
 342
 343 MODULE_AUTHOR("Michał Mirosław <mirq-linux@rere.qmqm.pl>");
 344 MODULE_DESCRIPTION("ENE CB710 memory card reader driver");
 345 MODULE_LICENSE("GPL");
 346 MODULE_DEVICE_TABLE(pci, cb710_pci_tbl);