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 static DEFINE_SPINLOCK(cb710_ida_lock);
  20
  21 void cb710_pci_update_config_reg(struct pci_dev *pdev,
  22         int reg, uint32_t mask, uint32_t xor)
  23 {
  24         u32 rval;
  25
  26         pci_read_config_dword(pdev, reg, &rval);
  27         rval = (rval & mask) ^ xor;
  28         pci_write_config_dword(pdev, reg, rval);
  29 }
  30 EXPORT_SYMBOL_GPL(cb710_pci_update_config_reg);
  31
  32 /* Some magic writes based on Windows driver init code */
  33 static int cb710_pci_configure(struct pci_dev *pdev)
  34 {
  35         unsigned int devfn = PCI_DEVFN(PCI_SLOT(pdev->devfn), 0);
  36         struct pci_dev *pdev0;
  37         u32 val;
  38
  39         cb710_pci_update_config_reg(pdev, 0x48,
  40                 ~0x000000FF, 0x0000003F);
  41
  42         pci_read_config_dword(pdev, 0x48, &val);
  43         if (val & 0x80000000)
  44                 return 0;
  45
  46         pdev0 = pci_get_slot(pdev->bus, devfn);
  47         if (!pdev0)
  48                 return -ENODEV;
  49
  50         if (pdev0->vendor == PCI_VENDOR_ID_ENE
  51             && pdev0->device == PCI_DEVICE_ID_ENE_720) {
  52                 cb710_pci_update_config_reg(pdev0, 0x8C,
  53                         ~0x00F00000, 0x00100000);
  54                 cb710_pci_update_config_reg(pdev0, 0xB0,
  55                         ~0x08000000, 0x08000000);
  56         }
  57
  58         cb710_pci_update_config_reg(pdev0, 0x8C,
  59                 ~0x00000F00, 0x00000200);
  60         cb710_pci_update_config_reg(pdev0, 0x90,
  61                 ~0x00060000, 0x00040000);
  62
  63         pci_dev_put(pdev0);
  64
  65         return 0;
  66 }
  67
  68 static irqreturn_t cb710_irq_handler(int irq, void *data)
  69 {
  70         struct cb710_chip *chip = data;
  71         struct cb710_slot *slot = &chip->slot[0];
  72         irqreturn_t handled = IRQ_NONE;
  73         unsigned nr;
  74
  75         spin_lock(&chip->irq_lock); /* incl. smp_rmb() */
  76
  77         for (nr = chip->slots; nr; ++slot, --nr) {
  78                 cb710_irq_handler_t handler_func = slot->irq_handler;
  79                 if (handler_func && handler_func(slot))
  80                         handled = IRQ_HANDLED;
  81         }
  82
  83         spin_unlock(&chip->irq_lock);
  84
  85         return handled;
  86 }
  87
  88 static void cb710_release_slot(struct device *dev)
  89 {
  90 #ifdef CONFIG_CB710_DEBUG_ASSUMPTIONS
  91         struct cb710_slot *slot = cb710_pdev_to_slot(to_platform_device(dev));
  92         struct cb710_chip *chip = cb710_slot_to_chip(slot);
  93
  94         /* slot struct can be freed now */
  95         atomic_dec(&chip->slot_refs_count);
  96 #endif
  97 }
  98
  99 static int cb710_register_slot(struct cb710_chip *chip,
 100         unsigned slot_mask, unsigned io_offset, const char *name)
 101 {
 102         int nr = chip->slots;
 103         struct cb710_slot *slot = &chip->slot[nr];
 104         int err;
 105
 106         dev_dbg(cb710_chip_dev(chip),
 107                 "register: %s.%d; slot %d; mask %d; IO offset: 0x%02X\n",
 108                 name, chip->platform_id, nr, slot_mask, io_offset);
 109
 110         /* slot->irq_handler == NULL here; this needs to be
 111          * seen before platform_device_register() */
 112         ++chip->slots;
 113         smp_wmb();
 114
 115         slot->iobase = chip->iobase + io_offset;
 116         slot->pdev.name = name;
 117         slot->pdev.id = chip->platform_id;
 118         slot->pdev.dev.parent = &chip->pdev->dev;
 119         slot->pdev.dev.release = cb710_release_slot;
 120
 121         err = platform_device_register(&slot->pdev);
 122
 123 #ifdef CONFIG_CB710_DEBUG_ASSUMPTIONS
 124         atomic_inc(&chip->slot_refs_count);
 125 #endif
 126
 127         if (err) {
 128                 /* device_initialize() called from platform_device_register()
 129                  * wants this on error path */
 130                 platform_device_put(&slot->pdev);
 131
 132                 /* slot->irq_handler == NULL here anyway, so no lock needed */
 133                 --chip->slots;
 134                 return err;
 135         }
 136
 137         chip->slot_mask |= slot_mask;
 138
 139         return 0;
 140 }
 141
 142 static void cb710_unregister_slot(struct cb710_chip *chip,
 143         unsigned slot_mask)
 144 {
 145         int nr = chip->slots - 1;
 146
 147         if (!(chip->slot_mask & slot_mask))
 148                 return;
 149
 150         platform_device_unregister(&chip->slot[nr].pdev);
 151
 152         /* complementary to spin_unlock() in cb710_set_irq_handler() */
 153         smp_rmb();
 154         BUG_ON(chip->slot[nr].irq_handler != NULL);
 155
 156         /* slot->irq_handler == NULL here, so no lock needed */
 157         --chip->slots;
 158         chip->slot_mask &= ~slot_mask;
 159 }
 160
 161 void cb710_set_irq_handler(struct cb710_slot *slot,
 162         cb710_irq_handler_t handler)
 163 {
 164         struct cb710_chip *chip = cb710_slot_to_chip(slot);
 165         unsigned long flags;
 166
 167         spin_lock_irqsave(&chip->irq_lock, flags);
 168         slot->irq_handler = handler;
 169         spin_unlock_irqrestore(&chip->irq_lock, flags);
 170 }
 171 EXPORT_SYMBOL_GPL(cb710_set_irq_handler);
 172
 173 #ifdef CONFIG_PM
 174
 175 static int cb710_suspend(struct pci_dev *pdev, pm_message_t state)
 176 {
 177         struct cb710_chip *chip = pci_get_drvdata(pdev);
 178
 179         devm_free_irq(&pdev->dev, pdev->irq, chip);
 180         pci_save_state(pdev);
 181         pci_disable_device(pdev);
 182         if (state.event & PM_EVENT_SLEEP)
 183                 pci_set_power_state(pdev, PCI_D3hot);
 184         return 0;
 185 }
 186
 187 static int cb710_resume(struct pci_dev *pdev)
 188 {
 189         struct cb710_chip *chip = pci_get_drvdata(pdev);
 190         int err;
 191
 192         pci_set_power_state(pdev, PCI_D0);
 193         pci_restore_state(pdev);
 194         err = pcim_enable_device(pdev);
 195         if (err)
 196                 return err;
 197
 198         return devm_request_irq(&pdev->dev, pdev->irq,
 199                 cb710_irq_handler, IRQF_SHARED, KBUILD_MODNAME, chip);
 200 }
 201
 202 #endif /* CONFIG_PM */
 203
 204 static int cb710_probe(struct pci_dev *pdev,
 205         const struct pci_device_id *ent)
 206 {
 207         struct cb710_chip *chip;
 208         unsigned long flags;
 209         u32 val;
 210         int err;
 211         int n = 0;
 212
 213         err = cb710_pci_configure(pdev);
 214         if (err)
 215                 return err;
 216
 217         /* this is actually magic... */
 218         pci_read_config_dword(pdev, 0x48, &val);
 219         if (!(val & 0x80000000)) {
 220                 pci_write_config_dword(pdev, 0x48, val|0x71000000);
 221                 pci_read_config_dword(pdev, 0x48, &val);
 222         }
 223
 224         dev_dbg(&pdev->dev, "PCI config[0x48] = 0x%08X\n", val);
 225         if (!(val & 0x70000000))
 226                 return -ENODEV;
 227         val = (val >> 28) & 7;
 228         if (val & CB710_SLOT_MMC)
 229                 ++n;
 230         if (val & CB710_SLOT_MS)
 231                 ++n;
 232         if (val & CB710_SLOT_SM)
 233                 ++n;
 234
 235         chip = devm_kzalloc(&pdev->dev,
 236                 sizeof(*chip) + n * sizeof(*chip->slot), GFP_KERNEL);
 237         if (!chip)
 238                 return -ENOMEM;
 239
 240         err = pcim_enable_device(pdev);
 241         if (err)
 242                 return err;
 243
 244         err = pcim_iomap_regions(pdev, 0x0001, KBUILD_MODNAME);
 245         if (err)
 246                 return err;
 247
 248         spin_lock_init(&chip->irq_lock);
 249         chip->pdev = pdev;
 250         chip->iobase = pcim_iomap_table(pdev)[0];
 251
 252         pci_set_drvdata(pdev, chip);
 253
 254         err = devm_request_irq(&pdev->dev, pdev->irq,
 255                 cb710_irq_handler, IRQF_SHARED, KBUILD_MODNAME, chip);
 256         if (err)
 257                 return err;
 258
 259         do {
 260                 if (!ida_pre_get(&cb710_ida, GFP_KERNEL))
 261                         return -ENOMEM;
 262
 263                 spin_lock_irqsave(&cb710_ida_lock, flags);
 264                 err = ida_get_new(&cb710_ida, &chip->platform_id);
 265                 spin_unlock_irqrestore(&cb710_ida_lock, flags);
 266
 267                 if (err && err != -EAGAIN)
 268                         return err;
 269         } while (err);
 270
 271
 272         dev_info(&pdev->dev, "id %d, IO 0x%p, IRQ %d\n",
 273                 chip->platform_id, chip->iobase, pdev->irq);
 274
 275         if (val & CB710_SLOT_MMC) {     /* MMC/SD slot */
 276                 err = cb710_register_slot(chip,
 277                         CB710_SLOT_MMC, 0x00, "cb710-mmc");
 278                 if (err)
 279                         return err;
 280         }
 281
 282         if (val & CB710_SLOT_MS) {      /* MemoryStick slot */
 283                 err = cb710_register_slot(chip,
 284                         CB710_SLOT_MS, 0x40, "cb710-ms");
 285                 if (err)
 286                         goto unreg_mmc;
 287         }
 288
 289         if (val & CB710_SLOT_SM) {      /* SmartMedia slot */
 290                 err = cb710_register_slot(chip,
 291                         CB710_SLOT_SM, 0x60, "cb710-sm");
 292                 if (err)
 293                         goto unreg_ms;
 294         }
 295
 296         return 0;
 297 unreg_ms:
 298         cb710_unregister_slot(chip, CB710_SLOT_MS);
 299 unreg_mmc:
 300         cb710_unregister_slot(chip, CB710_SLOT_MMC);
 301
 302 #ifdef CONFIG_CB710_DEBUG_ASSUMPTIONS
 303         BUG_ON(atomic_read(&chip->slot_refs_count) != 0);
 304 #endif
 305         return err;
 306 }
 307
 308 static void cb710_remove_one(struct pci_dev *pdev)
 309 {
 310         struct cb710_chip *chip = pci_get_drvdata(pdev);
 311         unsigned long flags;
 312
 313         cb710_unregister_slot(chip, CB710_SLOT_SM);
 314         cb710_unregister_slot(chip, CB710_SLOT_MS);
 315         cb710_unregister_slot(chip, CB710_SLOT_MMC);
 316 #ifdef CONFIG_CB710_DEBUG_ASSUMPTIONS
 317         BUG_ON(atomic_read(&chip->slot_refs_count) != 0);
 318 #endif
 319
 320         spin_lock_irqsave(&cb710_ida_lock, flags);
 321         ida_remove(&cb710_ida, chip->platform_id);
 322         spin_unlock_irqrestore(&cb710_ida_lock, flags);
 323 }
 324
 325 static const struct pci_device_id cb710_pci_tbl[] = {
 326         { PCI_VENDOR_ID_ENE, PCI_DEVICE_ID_ENE_CB710_FLASH,
 327                 PCI_ANY_ID, PCI_ANY_ID, },
 328         { 0, }
 329 };
 330
 331 static struct pci_driver cb710_driver = {
 332         .name = KBUILD_MODNAME,
 333         .id_table = cb710_pci_tbl,
 334         .probe = cb710_probe,
 335         .remove = cb710_remove_one,
 336 #ifdef CONFIG_PM
 337         .suspend = cb710_suspend,
 338         .resume = cb710_resume,
 339 #endif
 340 };
 341
 342 static int __init cb710_init_module(void)
 343 {
 344         return pci_register_driver(&cb710_driver);
 345 }
 346
 347 static void __exit cb710_cleanup_module(void)
 348 {
 349         pci_unregister_driver(&cb710_driver);
 350         ida_destroy(&cb710_ida);
 351 }
 352
 353 module_init(cb710_init_module);
 354 module_exit(cb710_cleanup_module);
 355
 356 MODULE_AUTHOR("Michał Mirosław <mirq-linux@rere.qmqm.pl>");
 357 MODULE_DESCRIPTION("ENE CB710 memory card reader driver");
 358 MODULE_LICENSE("GPL");
 359 MODULE_DEVICE_TABLE(pci, cb710_pci_tbl);