mmc: Driver for CB710/720 memory card reader (MMC part)

The code is divided in two parts. There is a virtual 'bus' driver
that handles PCI device and registers three new devices one per card
reader type. The other driver handles SD/MMC part of the reader.

Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
Signed-off-by: Pierre Ossman <pierre@ossman.eu>

1 files changed, 357 insertions, 0 deletions

diff --git a/drivers/misc/cb710/core.c b/drivers/misc/cb710/core.c
new file mode 100644
index 00000000000..b14eab0f2ba
--- /dev/null
+++ b/drivers/misc/cb710/core.c
@@ -0,0 +1,357 @@
+/*
+ *  cb710/core.c
+ *
+ *  Copyright by Michał Mirosław, 2008-2009
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/pci.h>
+#include <linux/spinlock.h>
+#include <linux/idr.h>
+#include <linux/cb710.h>
+
+static DEFINE_IDA(cb710_ida);
+static DEFINE_SPINLOCK(cb710_ida_lock);
+
+void cb710_pci_update_config_reg(struct pci_dev *pdev,
+	int reg, uint32_t mask, uint32_t xor)
+{
+	u32 rval;
+
+	pci_read_config_dword(pdev, reg, &rval);
+	rval = (rval & mask) ^ xor;
+	pci_write_config_dword(pdev, reg, rval);
+}
+EXPORT_SYMBOL_GPL(cb710_pci_update_config_reg);
+
+/* Some magic writes based on Windows driver init code */
+static int __devinit cb710_pci_configure(struct pci_dev *pdev)
+{
+	unsigned int devfn = PCI_DEVFN(PCI_SLOT(pdev->devfn), 0);
+	struct pci_dev *pdev0 = pci_get_slot(pdev->bus, devfn);
+	u32 val;
+
+	cb710_pci_update_config_reg(pdev, 0x48,
+		~0x000000FF, 0x0000003F);
+
+	pci_read_config_dword(pdev, 0x48, &val);
+	if (val & 0x80000000)
+		return 0;
+
+	if (!pdev0)
+		return -ENODEV;
+
+	if (pdev0->vendor == PCI_VENDOR_ID_ENE
+	    && pdev0->device == PCI_DEVICE_ID_ENE_720) {
+		cb710_pci_update_config_reg(pdev0, 0x8C,
+			~0x00F00000, 0x00100000);
+		cb710_pci_update_config_reg(pdev0, 0xB0,
+			~0x08000000, 0x08000000);
+	}
+
+	cb710_pci_update_config_reg(pdev0, 0x8C,
+		~0x00000F00, 0x00000200);
+	cb710_pci_update_config_reg(pdev0, 0x90,
+		~0x00060000, 0x00040000);
+
+	pci_dev_put(pdev0);
+
+	return 0;
+}
+
+static irqreturn_t cb710_irq_handler(int irq, void *data)
+{
+	struct cb710_chip *chip = data;
+	struct cb710_slot *slot = &chip->slot[0];
+	irqreturn_t handled = IRQ_NONE;
+	unsigned nr;
+
+	spin_lock(&chip->irq_lock); /* incl. smp_rmb() */
+
+	for (nr = chip->slots; nr; ++slot, --nr) {
+		cb710_irq_handler_t handler_func = slot->irq_handler;
+		if (handler_func && handler_func(slot))
+			handled = IRQ_HANDLED;
+	}
+
+	spin_unlock(&chip->irq_lock);
+
+	return handled;
+}
+
+static void cb710_release_slot(struct device *dev)
+{
+#ifdef CONFIG_CB710_DEBUG_ASSUMPTIONS
+	struct cb710_slot *slot = cb710_pdev_to_slot(to_platform_device(dev));
+	struct cb710_chip *chip = cb710_slot_to_chip(slot);
+
+	/* slot struct can be freed now */
+	atomic_dec(&chip->slot_refs_count);
+#endif
+}
+
+static int __devinit cb710_register_slot(struct cb710_chip *chip,
+	unsigned slot_mask, unsigned io_offset, const char *name)
+{
+	int nr = chip->slots;
+	struct cb710_slot *slot = &chip->slot[nr];
+	int err;
+
+	dev_dbg(cb710_chip_dev(chip),
+		"register: %s.%d; slot %d; mask %d; IO offset: 0x%02X\n",
+		name, chip->platform_id, nr, slot_mask, io_offset);
+
+	/* slot->irq_handler == NULL here; this needs to be
+	 * seen before platform_device_register() */
+	++chip->slots;
+	smp_wmb();
+
+	slot->iobase = chip->iobase + io_offset;
+	slot->pdev.name = name;
+	slot->pdev.id = chip->platform_id;
+	slot->pdev.dev.parent = &chip->pdev->dev;
+	slot->pdev.dev.release = cb710_release_slot;
+
+	err = platform_device_register(&slot->pdev);
+
+#ifdef CONFIG_CB710_DEBUG_ASSUMPTIONS
+	atomic_inc(&chip->slot_refs_count);
+#endif
+
+	if (err) {
+		/* device_initialize() called from platform_device_register()
+		 * wants this on error path */
+		platform_device_put(&slot->pdev);
+
+		/* slot->irq_handler == NULL here anyway, so no lock needed */
+		--chip->slots;
+		return err;
+	}
+
+	chip->slot_mask |= slot_mask;
+
+	return 0;
+}
+
+static void cb710_unregister_slot(struct cb710_chip *chip,
+	unsigned slot_mask)
+{
+	int nr = chip->slots - 1;
+
+	if (!(chip->slot_mask & slot_mask))
+		return;
+
+	platform_device_unregister(&chip->slot[nr].pdev);
+
+	/* complementary to spin_unlock() in cb710_set_irq_handler() */
+	smp_rmb();
+	BUG_ON(chip->slot[nr].irq_handler != NULL);
+
+	/* slot->irq_handler == NULL here, so no lock needed */
+	--chip->slots;
+	chip->slot_mask &= ~slot_mask;
+}
+
+void cb710_set_irq_handler(struct cb710_slot *slot,
+	cb710_irq_handler_t handler)
+{
+	struct cb710_chip *chip = cb710_slot_to_chip(slot);
+	unsigned long flags;
+
+	spin_lock_irqsave(&chip->irq_lock, flags);
+	slot->irq_handler = handler;
+	spin_unlock_irqrestore(&chip->irq_lock, flags);
+}
+EXPORT_SYMBOL_GPL(cb710_set_irq_handler);
+
+#ifdef CONFIG_PM
+
+static int cb710_suspend(struct pci_dev *pdev, pm_message_t state)
+{
+	struct cb710_chip *chip = pci_get_drvdata(pdev);
+
+	free_irq(pdev->irq, chip);
+	pci_save_state(pdev);
+	pci_disable_device(pdev);
+	if (state.event & PM_EVENT_SLEEP)
+		pci_set_power_state(pdev, PCI_D3cold);
+	return 0;
+}
+
+static int cb710_resume(struct pci_dev *pdev)
+{
+	struct cb710_chip *chip = pci_get_drvdata(pdev);
+	int err;
+
+	pci_set_power_state(pdev, PCI_D0);
+	pci_restore_state(pdev);
+	err = pcim_enable_device(pdev);
+	if (err)
+		return err;
+
+	return devm_request_irq(&pdev->dev, pdev->irq,
+		cb710_irq_handler, IRQF_SHARED, KBUILD_MODNAME, chip);
+}
+
+#endif /* CONFIG_PM */
+
+static int __devinit cb710_probe(struct pci_dev *pdev,
+	const struct pci_device_id *ent)
+{
+	struct cb710_chip *chip;
+	unsigned long flags;
+	u32 val;
+	int err;
+	int n = 0;
+
+	err = cb710_pci_configure(pdev);
+	if (err)
+		return err;
+
+	/* this is actually magic... */
+	pci_read_config_dword(pdev, 0x48, &val);
+	if (!(val & 0x80000000)) {
+		pci_write_config_dword(pdev, 0x48, val|0x71000000);
+		pci_read_config_dword(pdev, 0x48, &val);
+	}
+
+	dev_dbg(&pdev->dev, "PCI config[0x48] = 0x%08X\n", val);
+	if (!(val & 0x70000000))
+		return -ENODEV;
+	val = (val >> 28) & 7;
+	if (val & CB710_SLOT_MMC)
+		++n;
+	if (val & CB710_SLOT_MS)
+		++n;
+	if (val & CB710_SLOT_SM)
+		++n;
+
+	chip = devm_kzalloc(&pdev->dev,
+		sizeof(*chip) + n * sizeof(*chip->slot), GFP_KERNEL);
+	if (!chip)
+		return -ENOMEM;
+
+	err = pcim_enable_device(pdev);
+	if (err)
+		return err;
+
+	err = pcim_iomap_regions(pdev, 0x0001, KBUILD_MODNAME);
+	if (err)
+		return err;
+
+	chip->pdev = pdev;
+	chip->iobase = pcim_iomap_table(pdev)[0];
+
+	pci_set_drvdata(pdev, chip);
+
+	err = devm_request_irq(&pdev->dev, pdev->irq,
+		cb710_irq_handler, IRQF_SHARED, KBUILD_MODNAME, chip);
+	if (err)
+		return err;
+
+	do {
+		if (!ida_pre_get(&cb710_ida, GFP_KERNEL))
+			return -ENOMEM;
+
+		spin_lock_irqsave(&cb710_ida_lock, flags);
+		err = ida_get_new(&cb710_ida, &chip->platform_id);
+		spin_unlock_irqrestore(&cb710_ida_lock, flags);
+
+		if (err && err != -EAGAIN)
+			return err;
+	} while (err);
+
+
+	dev_info(&pdev->dev, "id %d, IO 0x%p, IRQ %d\n",
+		chip->platform_id, chip->iobase, pdev->irq);
+
+	if (val & CB710_SLOT_MMC) {	/* MMC/SD slot */
+		err = cb710_register_slot(chip,
+			CB710_SLOT_MMC, 0x00, "cb710-mmc");
+		if (err)
+			return err;
+	}
+
+	if (val & CB710_SLOT_MS) {	/* MemoryStick slot */
+		err = cb710_register_slot(chip,
+			CB710_SLOT_MS, 0x40, "cb710-ms");
+		if (err)
+			goto unreg_mmc;
+	}
+
+	if (val & CB710_SLOT_SM) {	/* SmartMedia slot */
+		err = cb710_register_slot(chip,
+			CB710_SLOT_SM, 0x60, "cb710-sm");
+		if (err)
+			goto unreg_ms;
+	}
+
+	return 0;
+unreg_ms:
+	cb710_unregister_slot(chip, CB710_SLOT_MS);
+unreg_mmc:
+	cb710_unregister_slot(chip, CB710_SLOT_MMC);
+
+#ifdef CONFIG_CB710_DEBUG_ASSUMPTIONS
+	BUG_ON(atomic_read(&chip->slot_refs_count) != 0);
+#endif
+	return err;
+}
+
+static void __devexit cb710_remove_one(struct pci_dev *pdev)
+{
+	struct cb710_chip *chip = pci_get_drvdata(pdev);
+	unsigned long flags;
+
+	cb710_unregister_slot(chip, CB710_SLOT_SM);
+	cb710_unregister_slot(chip, CB710_SLOT_MS);
+	cb710_unregister_slot(chip, CB710_SLOT_MMC);
+#ifdef CONFIG_CB710_DEBUG_ASSUMPTIONS
+	BUG_ON(atomic_read(&chip->slot_refs_count) != 0);
+#endif
+
+	spin_lock_irqsave(&cb710_ida_lock, flags);
+	ida_remove(&cb710_ida, chip->platform_id);
+	spin_unlock_irqrestore(&cb710_ida_lock, flags);
+}
+
+static const struct pci_device_id cb710_pci_tbl[] = {
+	{ PCI_VENDOR_ID_ENE, PCI_DEVICE_ID_ENE_CB710_FLASH,
+		PCI_ANY_ID, PCI_ANY_ID, },
+	{ 0, }
+};
+
+static struct pci_driver cb710_driver = {
+	.name = KBUILD_MODNAME,
+	.id_table = cb710_pci_tbl,
+	.probe = cb710_probe,
+	.remove = __devexit_p(cb710_remove_one),
+#ifdef CONFIG_PM
+	.suspend = cb710_suspend,
+	.resume = cb710_resume,
+#endif
+};
+
+static int __init cb710_init_module(void)
+{
+	return pci_register_driver(&cb710_driver);
+}
+
+static void __exit cb710_cleanup_module(void)
+{
+	pci_unregister_driver(&cb710_driver);
+	ida_destroy(&cb710_ida);
+}
+
+module_init(cb710_init_module);
+module_exit(cb710_cleanup_module);
+
+MODULE_AUTHOR("Michał Mirosław <mirq-linux@rere.qmqm.pl>");
+MODULE_DESCRIPTION("ENE CB710 memory card reader driver");
+MODULE_LICENSE("GPL");
+MODULE_DEVICE_TABLE(pci, cb710_pci_tbl);