#include "pci.h"

#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/interrupt.h>

#include "char.h"
#include "harddoom.h"
#include "util.h"
#include "harddoomdev.h"
#include "private_data.h"

void handle_pong_sync(struct doom_data *doom_data)
{
	up(&doom_data->pong_sem);
}

irqreturn_t doom_irq(int irq, void *dev)
{
	uint32_t interrupts;
	struct doom_data *doom_data;

	void __iomem *iomem;

	doom_data = dev;
	iomem = doom_data->iomem;

	interrupts = ioread32(iomem + HARDDOOM_INTR) & ioread32(iomem + HARDDOOM_INTR_ENABLE);
	iowrite32(interrupts, iomem + HARDDOOM_INTR);

	if (!interrupts) {
		return IRQ_NONE;
	}

	if (interrupts & HARDDOOM_INTR_PONG_SYNC) {
		handle_pong_sync(doom_data);
		interrupts &= ~HARDDOOM_INTR_PONG_SYNC;
	}

	if (interrupts & HARDDOOM_INTR_PONG_ASYNC) {
		up(&doom_data->pong_async_sem);
		iowrite32(HARDDOOM_INTR_MASK & (~HARDDOOM_INTR_PONG_ASYNC),
				iomem + HARDDOOM_INTR_ENABLE);
	}

	return IRQ_HANDLED;
}

int init_pci(struct pci_dev *dev)
{
	struct doom_data *doom_data;
	int err = 0;

	ORFAIL(pci_enable_device(dev), error_enable);
	ORFAIL(pci_request_regions(dev, "harddoom"), error_regions);

	doom_data = kmalloc(sizeof(*doom_data), GFP_KERNEL);
	if (doom_data == NULL) {
		err = -ENOMEM;
		goto error_kmalloc;
	}
	pci_set_drvdata(dev, doom_data);
	doom_data->iomem = pci_iomap(dev, 0, 0);
	ORFAIL_NULL(doom_data->iomem, -ENOMEM, error_iomem);
	doom_data->pci_device = &dev->dev;

	pci_set_master(dev);
	pci_set_dma_mask(dev, DMA_BIT_MASK(32));
	pci_set_consistent_dma_mask(dev, DMA_BIT_MASK(32));

	mutex_init(&doom_data->cmd_mutex);
	mutex_init(&doom_data->ping_mutex);
	sema_init(&doom_data->pong_sem, 0);
	sema_init(&doom_data->pong_async_sem, 0);
	doom_data->cmd_counter = 0;

	ORFAIL(request_irq(dev->irq, doom_irq, IRQF_SHARED,
			"doom", doom_data), error_irq);

	return 0;

error_irq:
	pci_clear_master(dev);
	pci_iounmap(dev, doom_data->iomem);
error_iomem:
	kfree(doom_data);
error_kmalloc:
	pci_release_regions(dev);
error_regions:
	pci_disable_device(dev);
error_enable:
	return err;
}

void cleanup_pci(struct pci_dev *dev)
{
	struct doom_data *doom_data;

	doom_data = pci_get_drvdata(dev);

	free_irq(dev->irq, doom_data);
	pci_clear_master(dev);
	pci_iounmap(dev, doom_data->iomem);
	kfree(doom_data);
	pci_release_regions(dev);
	pci_disable_device(dev);
}

int doom_probe(struct pci_dev *dev, const struct pci_device_id *id)
{
	int err = 0;

	ORFAIL(init_pci(dev), error_pci);
	start_dev(dev);
	ORFAIL(new_doomdev(dev), error_doomdev);

	return 0;

error_doomdev:
	shutdown_dev(dev);
	cleanup_pci(dev);
error_pci:
	return err;
}

void doom_remove (struct pci_dev *dev)
{
	struct doom_data *doom_data;

	doom_data = pci_get_drvdata(dev);

	destroy_doomdev(doom_data);
	shutdown_dev(dev);
	cleanup_pci(dev);
}

int doom_suspend (struct pci_dev *dev, pm_message_t state)
{
	return 0;
}

int doom_suspend_late (struct pci_dev *dev, pm_message_t state)
{
	return 0;
}

int doom_resume_early (struct pci_dev *dev)
{
	return 0;
}

int doom_resume (struct pci_dev *dev)
{
	return 0;
}

void doom_shutdown (struct pci_dev *dev)
{
}

struct pci_device_id device_ids[1] = {
	{ PCI_DEVICE(HARDDOOM_VENDOR_ID, HARDDOOM_DEVICE_ID) }
};

struct pci_driver driver = {
	.name = "harddoom",
	.id_table = device_ids,
	.probe = doom_probe,
	.remove = doom_remove,
	.suspend = doom_suspend,
	.suspend_late = doom_suspend_late,
	.resume_early = doom_resume_early,
	.resume = doom_resume,
	.shutdown = doom_shutdown
};

int pci_init(void)
{
	return pci_register_driver(&driver);
}

void pci_cleanup(void)
{
	pci_unregister_driver(&driver);
}