/*
 *  tifm_7xx1.c - TI FlashMedia driver
 *
 *  Copyright (C) 2006 Alex Dubov <oakad@yahoo.com>
 *
 * 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/tifm.h>
#include <linux/dma-mapping.h>
#include <linux/freezer.h>

#define DRIVER_NAME "tifm_7xx1"
#define DRIVER_VERSION "0.7"

static void tifm_7xx1_eject(struct tifm_adapter *fm, struct tifm_dev *sock)
{
	unsigned long flags;

	spin_lock_irqsave(&fm->lock, flags);
	fm->socket_change_set |= 1 << sock->socket_id;
	wake_up_all(&fm->change_set_notify);
	spin_unlock_irqrestore(&fm->lock, flags);
}

static irqreturn_t tifm_7xx1_isr(int irq, void *dev_id)
{
	struct tifm_adapter *fm = dev_id;
	struct tifm_dev *sock;
	unsigned int irq_status;
	unsigned int sock_irq_status, cnt;

	spin_lock(&fm->lock);
	irq_status = readl(fm->addr + FM_INTERRUPT_STATUS);
	if (irq_status == 0 || irq_status == (~0)) {
		spin_unlock(&fm->lock);
		return IRQ_NONE;
	}

	if (irq_status & TIFM_IRQ_ENABLE) {
		writel(TIFM_IRQ_ENABLE, fm->addr + FM_CLEAR_INTERRUPT_ENABLE);

		for (cnt = 0; cnt < fm->num_sockets; cnt++) {
			sock = fm->sockets[cnt];
			sock_irq_status = (irq_status >> cnt)
					  & (TIFM_IRQ_FIFOMASK(1)
					     | TIFM_IRQ_CARDMASK(1));

			if (sock && sock_irq_status)
				sock->signal_irq(sock, sock_irq_status);
		}

		fm->socket_change_set |= irq_status
					 & ((1 << fm->num_sockets) - 1);
	}
	writel(irq_status, fm->addr + FM_INTERRUPT_STATUS);

	if (!fm->socket_change_set)
		writel(TIFM_IRQ_ENABLE, fm->addr + FM_SET_INTERRUPT_ENABLE);
	else
		wake_up_all(&fm->change_set_notify);

	spin_unlock(&fm->lock);
	return IRQ_HANDLED;
}

static tifm_media_id tifm_7xx1_toggle_sock_power(char __iomem *sock_addr,
						 int is_x2)
{
	unsigned int s_state;
	int cnt;

	writel(0x0e00, sock_addr + SOCK_CONTROL);

	for (cnt = 0; cnt < 100; cnt++) {
		if (!(TIFM_SOCK_STATE_POWERED
		      & readl(sock_addr + SOCK_PRESENT_STATE)))
			break;
		msleep(10);
	}

	s_state = readl(sock_addr + SOCK_PRESENT_STATE);
	if (!(TIFM_SOCK_STATE_OCCUPIED & s_state))
		return FM_NULL;

	if (is_x2) {
		writel((s_state & 7) | 0x0c00, sock_addr + SOCK_CONTROL);
	} else {
		// SmartMedia cards need extra 40 msec
		if (((readl(sock_addr + SOCK_PRESENT_STATE) >> 4) & 7) == 1)
			msleep(40);
		writel(readl(sock_addr + SOCK_CONTROL) | TIFM_CTRL_LED,
		       sock_addr + SOCK_CONTROL);
		msleep(10);
		writel((s_state & 0x7) | 0x0c00 | TIFM_CTRL_LED,
			sock_addr + SOCK_CONTROL);
	}

	for (cnt = 0; cnt < 100; cnt++) {
		if ((TIFM_SOCK_STATE_POWERED
		     & readl(sock_addr + SOCK_PRESENT_STATE)))
			break;
		msleep(10);
	}

	if (!is_x2)
		writel(readl(sock_addr + SOCK_CONTROL) & (~TIFM_CTRL_LED),
		       sock_addr + SOCK_CONTROL);

	return (readl(sock_addr + SOCK_PRESENT_STATE) >> 4) & 7;
}

inline static char __iomem *
tifm_7xx1_sock_addr(char __iomem *base_addr, unsigned int sock_num)
{
	return base_addr + ((sock_num + 1) << 10);
}

static int tifm_7xx1_switch_media(void *data)
{
	struct tifm_adapter *fm = data;
	unsigned long flags;
	tifm_media_id media_id;
	char *card_name = "xx";
	int cnt, rc;
	struct tifm_dev *sock;
	unsigned int socket_change_set;

	while (1) {
		rc = wait_event_interruptible(fm->change_set_notify,
					      fm->socket_change_set);
		if (rc == -ERESTARTSYS)
			try_to_freeze();

		spin_lock_irqsave(&fm->lock, flags);
		socket_change_set = fm->socket_change_set;
		fm->socket_change_set = 0;

		dev_dbg(fm->dev, "checking media set %x\n",
			socket_change_set);

		if (kthread_should_stop())
			socket_change_set = (1 << fm->num_sockets) - 1;
		spin_unlock_irqrestore(&fm->lock, flags);

		if (!socket_change_set)
			continue;

		spin_lock_irqsave(&fm->lock, flags);
		for (cnt = 0; cnt < fm->num_sockets; cnt++) {
			if (!(socket_change_set & (1 << cnt)))
				continue;
			sock = fm->sockets[cnt];
			if (sock) {
				printk(KERN_INFO DRIVER_NAME
				       ": demand removing card from socket %d\n",
				       cnt);
				fm->sockets[cnt] = NULL;
				spin_unlock_irqrestore(&fm->lock, flags);
				device_unregister(&sock->dev);
				spin_lock_irqsave(&fm->lock, flags);
				writel(0x0e00,
				       tifm_7xx1_sock_addr(fm->addr, cnt)
				       + SOCK_CONTROL);
			}
			if (kthread_should_stop())
				continue;

			spin_unlock_irqrestore(&fm->lock, flags);
			media_id = tifm_7xx1_toggle_sock_power(
					tifm_7xx1_sock_addr(fm->addr, cnt),
					fm->num_sockets == 2);
			if (media_id) {
				sock = tifm_alloc_device(fm);
				if (sock) {
					sock->addr = tifm_7xx1_sock_addr(fm->addr,
									 cnt);
					sock->media_id = media_id;
					sock->socket_id = cnt;
					switch (media_id) {
					case 1:
						card_name = "xd";
						break;
					case 2:
						card_name = "ms";
						break;
					case 3:
						card_name = "sd";
						break;
					default:
						tifm_free_device(&sock->dev);
						spin_lock_irqsave(&fm->lock, flags);
						continue;
					}
					snprintf(sock->dev.bus_id, BUS_ID_SIZE,
						 "tifm_%s%u:%u", card_name,
						 fm->id, cnt);
					printk(KERN_INFO DRIVER_NAME
					       ": %s card detected in socket %d\n",
					       card_name, cnt);
					if (!device_register(&sock->dev)) {
						spin_lock_irqsave(&fm->lock, flags);
						if (!fm->sockets[cnt]) {
							fm->sockets[cnt] = sock;
							sock = NULL;
						}
						spin_unlock_irqrestore(&fm->lock, flags);
					}
					if (sock)
						tifm_free_device(&sock->dev);
				}
				spin_lock_irqsave(&fm->lock, flags);
			}
		}

		if (!kthread_should_stop()) {
			writel(TIFM_IRQ_FIFOMASK(socket_change_set)
			       | TIFM_IRQ_CARDMASK(socket_change_set),
			       fm->addr + FM_CLEAR_INTERRUPT_ENABLE);
			writel(TIFM_IRQ_FIFOMASK(socket_change_set)
			       | TIFM_IRQ_CARDMASK(socket_change_set),
			       fm->addr + FM_SET_INTERRUPT_ENABLE);
			writel(TIFM_IRQ_ENABLE,
			       fm->addr + FM_SET_INTERRUPT_ENABLE);
			spin_unlock_irqrestore(&fm->lock, flags);
		} else {
			for (cnt = 0; cnt < fm->num_sockets; cnt++) {
				if (fm->sockets[cnt])
					fm->socket_change_set |= 1 << cnt;
			}
			if (!fm->socket_change_set) {
				spin_unlock_irqrestore(&fm->lock, flags);
				return 0;
			} else {
				spin_unlock_irqrestore(&fm->lock, flags);
			}
		}
	}
	return 0;
}

#ifdef CONFIG_PM

static int tifm_7xx1_suspend(struct pci_dev *dev, pm_message_t state)
{
	dev_dbg(&dev->dev, "suspending host\n");

	pci_save_state(dev);
	pci_enable_wake(dev, pci_choose_state(dev, state), 0);
	pci_disable_device(dev);
	pci_set_power_state(dev, pci_choose_state(dev, state));
	return 0;
}

static int tifm_7xx1_resume(struct pci_dev *dev)
{
	struct tifm_adapter *fm = pci_get_drvdata(dev);
	int cnt, rc;
	unsigned long flags;
	tifm_media_id new_ids[fm->num_sockets];

	pci_set_power_state(dev, PCI_D0);
	pci_restore_state(dev);
	rc = pci_enable_device(dev);
	if (rc)
		return rc;
	pci_set_master(dev);

	dev_dbg(&dev->dev, "resuming host\n");

	for (cnt = 0; cnt < fm->num_sockets; cnt++)
		new_ids[cnt] = tifm_7xx1_toggle_sock_power(
					tifm_7xx1_sock_addr(fm->addr, cnt),
					fm->num_sockets == 2);
	spin_lock_irqsave(&fm->lock, flags);
	fm->socket_change_set = 0;
	for (cnt = 0; cnt < fm->num_sockets; cnt++) {
		if (fm->sockets[cnt]) {
			if (fm->sockets[cnt]->media_id == new_ids[cnt])
				fm->socket_change_set |= 1 << cnt;

			fm->sockets[cnt]->media_id = new_ids[cnt];
		}
	}

	writel(TIFM_IRQ_ENABLE | TIFM_IRQ_SOCKMASK((1 << fm->num_sockets) - 1),
	       fm->addr + FM_SET_INTERRUPT_ENABLE);
	if (!fm->socket_change_set) {
		spin_unlock_irqrestore(&fm->lock, flags);
		return 0;
	} else {
		fm->socket_change_set = 0;
		spin_unlock_irqrestore(&fm->lock, flags);
	}

	wait_event_timeout(fm->change_set_notify, fm->socket_change_set, HZ);

	spin_lock_irqsave(&fm->lock, flags);
	writel(TIFM_IRQ_FIFOMASK(fm->socket_change_set)
	       | TIFM_IRQ_CARDMASK(fm->socket_change_set),
	       fm->addr + FM_CLEAR_INTERRUPT_ENABLE);
	writel(TIFM_IRQ_FIFOMASK(fm->socket_change_set)
	       | TIFM_IRQ_CARDMASK(fm->socket_change_set),
	       fm->addr + FM_SET_INTERRUPT_ENABLE);
	writel(TIFM_IRQ_ENABLE,
	       fm->addr + FM_SET_INTERRUPT_ENABLE);
	fm->socket_change_set = 0;

	spin_unlock_irqrestore(&fm->lock, flags);
	return 0;
}

#else

#define tifm_7xx1_suspend NULL
#define tifm_7xx1_resume NULL

#endif /* CONFIG_PM */

static int tifm_7xx1_probe(struct pci_dev *dev,
			   const struct pci_device_id *dev_id)
{
	struct tifm_adapter *fm;
	int pci_dev_busy = 0;
	int rc;

	rc = pci_set_dma_mask(dev, DMA_32BIT_MASK);
	if (rc)
		return rc;

	rc = pci_enable_device(dev);
	if (rc)
		return rc;

	pci_set_master(dev);

	rc = pci_request_regions(dev, DRIVER_NAME);
	if (rc) {
		pci_dev_busy = 1;
		goto err_out;
	}

	pci_intx(dev, 1);

	fm = tifm_alloc_adapter();
	if (!fm) {
		rc = -ENOMEM;
		goto err_out_int;
	}

	fm->dev = &dev->dev;
	fm->num_sockets = (dev->device == PCI_DEVICE_ID_TI_XX21_XX11_FM)
			  ? 4 : 2;
	fm->sockets = kzalloc(sizeof(struct tifm_dev*) * fm->num_sockets,
			      GFP_KERNEL);
	if (!fm->sockets)
		goto err_out_free;

	fm->eject = tifm_7xx1_eject;
	pci_set_drvdata(dev, fm);

	fm->addr = ioremap(pci_resource_start(dev, 0),
			   pci_resource_len(dev, 0));
	if (!fm->addr)
		goto err_out_free;

	rc = request_irq(dev->irq, tifm_7xx1_isr, IRQF_SHARED, DRIVER_NAME, fm);
	if (rc)
		goto err_out_unmap;

	init_waitqueue_head(&fm->change_set_notify);
	rc = tifm_add_adapter(fm, tifm_7xx1_switch_media);
	if (rc)
		goto err_out_irq;

	writel(TIFM_IRQ_SETALL, fm->addr + FM_CLEAR_INTERRUPT_ENABLE);
	writel(TIFM_IRQ_ENABLE | TIFM_IRQ_SOCKMASK((1 << fm->num_sockets) - 1),
	       fm->addr + FM_SET_INTERRUPT_ENABLE);
	wake_up_process(fm->media_switcher);
	return 0;

err_out_irq:
	free_irq(dev->irq, fm);
err_out_unmap:
	iounmap(fm->addr);
err_out_free:
	pci_set_drvdata(dev, NULL);
	tifm_free_adapter(fm);
err_out_int:
	pci_intx(dev, 0);
	pci_release_regions(dev);
err_out:
	if (!pci_dev_busy)
		pci_disable_device(dev);
	return rc;
}

static void tifm_7xx1_remove(struct pci_dev *dev)
{
	struct tifm_adapter *fm = pci_get_drvdata(dev);
	unsigned long flags;

	writel(TIFM_IRQ_SETALL, fm->addr + FM_CLEAR_INTERRUPT_ENABLE);
	mmiowb();
	free_irq(dev->irq, fm);

	spin_lock_irqsave(&fm->lock, flags);
	fm->socket_change_set = (1 << fm->num_sockets) - 1;
	spin_unlock_irqrestore(&fm->lock, flags);

	kthread_stop(fm->media_switcher);

	tifm_remove_adapter(fm);

	pci_set_drvdata(dev, NULL);

	iounmap(fm->addr);
	pci_intx(dev, 0);
	pci_release_regions(dev);

	pci_disable_device(dev);
	tifm_free_adapter(fm);
}

static struct pci_device_id tifm_7xx1_pci_tbl [] = {
	{ PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_XX21_XX11_FM, PCI_ANY_ID,
	  PCI_ANY_ID, 0, 0, 0 }, /* xx21 - the one I have */
        { PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_XX12_FM, PCI_ANY_ID,
	  PCI_ANY_ID, 0, 0, 0 },
	{ PCI_VENDOR_ID_TI, PCI_DEVICE_ID_TI_XX20_FM, PCI_ANY_ID,
	  PCI_ANY_ID, 0, 0, 0 },
	{ }
};

static struct pci_driver tifm_7xx1_driver = {
	.name = DRIVER_NAME,
	.id_table = tifm_7xx1_pci_tbl,
	.probe = tifm_7xx1_probe,
	.remove = tifm_7xx1_remove,
	.suspend = tifm_7xx1_suspend,
	.resume = tifm_7xx1_resume,
};

static int __init tifm_7xx1_init(void)
{
	return pci_register_driver(&tifm_7xx1_driver);
}

static void __exit tifm_7xx1_exit(void)
{
	pci_unregister_driver(&tifm_7xx1_driver);
}

MODULE_AUTHOR("Alex Dubov");
MODULE_DESCRIPTION("TI FlashMedia host driver");
MODULE_LICENSE("GPL");
MODULE_DEVICE_TABLE(pci, tifm_7xx1_pci_tbl);
MODULE_VERSION(DRIVER_VERSION);

module_init(tifm_7xx1_init);
module_exit(tifm_7xx1_exit);