/*
 * Init/exit code for the module. Basically, creates/removes /sys/class/rc
 */
int __init edac_mc_sysfs_init(void)
{
	struct bus_type *edac_subsys;
	int err;

	/* get the /sys/devices/system/edac subsys reference */
	edac_subsys = edac_get_sysfs_subsys();
	if (edac_subsys == NULL) {
		edac_dbg(1, "no edac_subsys\n");
		return -EINVAL;
	}

	mci_pdev = kzalloc(sizeof(*mci_pdev), GFP_KERNEL);

	mci_pdev->bus = edac_subsys;
	mci_pdev->type = &mc_attr_type;
	device_initialize(mci_pdev);
	dev_set_name(mci_pdev, "mc");

	err = device_add(mci_pdev);
	if (err < 0)
		return err;

	edac_dbg(0, "device %s created\n", dev_name(mci_pdev));

	return 0;
}

/*
 *
 * edac_pci_create_sysfs
 *
 *	Create the controls/attributes for the specified EDAC PCI device
 */
int edac_pci_create_sysfs(struct edac_pci_ctl_info *pci)
{
	int err;
	struct kobject *edac_kobj = &pci->kobj;

	edac_dbg(0, "idx=%d\n", pci->pci_idx);

	/* create the top main EDAC PCI kobject, IF needed */
	err = edac_pci_main_kobj_setup();
	if (err)
		return err;

	/* Create this instance's kobject under the MAIN kobject */
	err = edac_pci_create_instance_kobj(pci, pci->pci_idx);
	if (err)
		goto unregister_cleanup;

	err = sysfs_create_link(edac_kobj, &pci->dev->kobj, EDAC_PCI_SYMLINK);
	if (err) {
		edac_dbg(0, "sysfs_create_link() returned err= %d\n", err);
		goto symlink_fail;
	}

	return 0;

	/* Error unwind stack */
symlink_fail:
	edac_pci_unregister_sysfs_instance_kobj(pci);

unregister_cleanup:
	edac_pci_main_kobj_teardown();

	return err;
}

/*
 * edac_pci_create_instance_kobj
 *
 *	construct one EDAC PCI instance's kobject for use
 */
static int edac_pci_create_instance_kobj(struct edac_pci_ctl_info *pci, int idx)
{
	struct kobject *main_kobj;
	int err;

	edac_dbg(0, "\n");

	/* First bump the ref count on the top main kobj, which will
	 * track the number of PCI instances we have, and thus nest
	 * properly on keeping the module loaded
	 */
	main_kobj = kobject_get(edac_pci_top_main_kobj);
	if (!main_kobj) {
		err = -ENODEV;
		goto error_out;
	}

	/* And now register this new kobject under the main kobj */
	err = kobject_init_and_add(&pci->kobj, &ktype_pci_instance,
				   edac_pci_top_main_kobj, "pci%d", idx);
	if (err != 0) {
		edac_dbg(2, "failed to register instance pci%d\n", idx);
		kobject_put(edac_pci_top_main_kobj);
		goto error_out;
	}

	kobject_uevent(&pci->kobj, KOBJ_ADD);
	edac_dbg(1, "Register instance 'pci%d' kobject\n", idx);

	return 0;

	/* Error unwind statck */
error_out:
	return err;
}

/*
 * edac_pci_main_kobj_teardown()
 *
 *	if no longer linked (needed) remove the top level EDAC PCI
 *	kobject with its controls and attributes
 */
static void edac_pci_main_kobj_teardown(void)
{
	edac_dbg(0, "\n");

	/* Decrement the count and only if no more controller instances
	 * are connected perform the unregisteration of the top level
	 * main kobj
	 */
	if (atomic_dec_return(&edac_pci_sysfs_refcount) == 0) {
		edac_dbg(0, "called kobject_put on main kobj\n");
		kobject_put(edac_pci_top_main_kobj);
	}
}

static int how_many_channels(struct pci_dev *pdev)
{
    unsigned char capid0_8b; /* 8th byte of CAPID0 */

    pci_read_config_byte(pdev, I3200_CAPID0 + 8, &capid0_8b);
    if (capid0_8b & 0x20) { /* check DCD: Dual Channel Disable */
        edac_dbg(0, "In single channel mode\n");
        return 1;
    } else {
        edac_dbg(0, "In dual channel mode\n");
        return 2;
    }
}

/*
 * edac_device_create_sysfs() Constructor
 *
 * accept a created edac_device control structure
 * and 'export' it to sysfs. The 'main' kobj should already have been
 * created. 'instance' and 'block' kobjects should be registered
 * along with any 'block' attributes from the low driver. In addition,
 * the main attributes (if any) are connected to the main kobject of
 * the control structure.
 *
 * Return:
 *	0	Success
 *	!0	Failure
 */
int edac_device_create_sysfs(struct edac_device_ctl_info *edac_dev)
{
	int err;
	struct kobject *edac_kobj = &edac_dev->kobj;

	edac_dbg(0, "idx=%d\n", edac_dev->dev_idx);

	/*  go create any main attributes callers wants */
	err = edac_device_add_main_sysfs_attributes(edac_dev);
	if (err) {
		edac_dbg(0, "failed to add sysfs attribs\n");
		goto err_out;
	}

	/* create a symlink from the edac device
	 * to the platform 'device' being used for this
	 */
	err = sysfs_create_link(edac_kobj,
				&edac_dev->dev->kobj, EDAC_DEVICE_SYMLINK);
	if (err) {
		edac_dbg(0, "sysfs_create_link() returned err= %d\n", err);
		goto err_remove_main_attribs;
	}

	/* Create the first level instance directories
	 * In turn, the nested blocks beneath the instances will
	 * be registered as well
	 */
	err = edac_device_create_instances(edac_dev);
	if (err) {
		edac_dbg(0, "edac_device_create_instances() returned err= %d\n",
			 err);
		goto err_remove_link;
	}


	edac_dbg(4, "create-instances done, idx=%d\n", edac_dev->dev_idx);

	return 0;

	/* Error unwind stack */
err_remove_link:
	/* remove the sym link */
	sysfs_remove_link(&edac_dev->kobj, EDAC_DEVICE_SYMLINK);

err_remove_main_attribs:
	edac_device_remove_main_sysfs_attributes(edac_dev);

err_out:
	return err;
}

/*
 * edac_device_unregister_sysfs_main_kobj:
 *	the '..../edac/<name>' kobject
 */
void edac_device_unregister_sysfs_main_kobj(struct edac_device_ctl_info *dev)
{
	edac_dbg(0, "\n");
	edac_dbg(4, "name of kobject is: %s\n", kobject_name(&dev->kobj));

	/*
	 * Unregister the edac device's kobject and
	 * allow for reference count to reach 0 at which point
	 * the callback will be called to:
	 *   a) module_put() this module
	 *   b) 'kfree' the memory
	 */
	kobject_put(&dev->kobj);
}

/*
 * Init/exit code for the module. Basically, creates/removes /sys/class/rc
 */
int __init edac_mc_sysfs_init(void)
{
	int err;

	mci_pdev = kzalloc(sizeof(*mci_pdev), GFP_KERNEL);
	if (!mci_pdev) {
		err = -ENOMEM;
		goto out;
	}

	mci_pdev->bus = edac_get_sysfs_subsys();
	mci_pdev->type = &mc_attr_type;
	device_initialize(mci_pdev);
	dev_set_name(mci_pdev, "mc");

	err = device_add(mci_pdev);
	if (err < 0)
		goto out_dev_free;

	edac_dbg(0, "device %s created\n", dev_name(mci_pdev));

	return 0;

 out_dev_free:
	kfree(mci_pdev);
 out:
	return err;
}

/*
 * edac_pci_do_parity_check
 *
 *	performs the actual PCI parity check operation
 */
void edac_pci_do_parity_check(void)
{
	int before_count;

	edac_dbg(3, "\n");

	/* if policy has PCI check off, leave now */
	if (!check_pci_errors)
		return;

	before_count = atomic_read(&pci_parity_count);

	/* scan all PCI devices looking for a Parity Error on devices and
	 * bridges.
	 * The iterator calls pci_get_device() which might sleep, thus
	 * we cannot disable interrupts in this scan.
	 */
	edac_pci_dev_parity_iterator(edac_pci_dev_parity_test);

	/* Only if operator has selected panic on PCI Error */
	if (edac_pci_get_panic_on_pe()) {
		/* If the count is different 'after' from 'before' */
		if (before_count != atomic_read(&pci_parity_count))
			panic("EDAC: PCI Parity Error");
	}
}

static void mci_attr_release(struct device *dev)
{
	struct mem_ctl_info *mci = container_of(dev, struct mem_ctl_info, dev);

	edac_dbg(1, "Releasing csrow device %s\n", dev_name(dev));
	kfree(mci);
}

static void dimm_attr_release(struct device *dev)
{
	struct dimm_info *dimm = container_of(dev, struct dimm_info, dev);

	edac_dbg(1, "Releasing dimm device %s\n", dev_name(dev));
	kfree(dimm);
}

static void i5100_init_csrows(struct mem_ctl_info *mci)
{
	int i;
	struct i5100_priv *priv = mci->pvt_info;

	for (i = 0; i < mci->tot_dimms; i++) {
		struct dimm_info *dimm;
		const unsigned long npages = i5100_npages(mci, i);
		const unsigned chan = i5100_csrow_to_chan(mci, i);
		const unsigned rank = i5100_csrow_to_rank(mci, i);

		if (!npages)
			continue;

		dimm = EDAC_DIMM_PTR(mci->layers, mci->dimms, mci->n_layers,
			       chan, rank, 0);

		dimm->nr_pages = npages;
		dimm->grain = 32;
		dimm->dtype = (priv->mtr[chan][rank].width == 4) ?
				DEV_X4 : DEV_X8;
		dimm->mtype = MEM_RDDR2;
		dimm->edac_mode = EDAC_SECDED;
		snprintf(dimm->label, sizeof(dimm->label), "DIMM%u",
			 i5100_rank_to_slot(mci, chan, rank));

		edac_dbg(2, "dimm channel %d, rank %d, size %ld\n",
			 chan, rank, (long)PAGES_TO_MiB(npages));
	}
}

/* Create a DIMM object under specifed memory controller device */
static int edac_create_dimm_object(struct mem_ctl_info *mci,
				   struct dimm_info *dimm,
				   int index)
{
	int err;
	dimm->mci = mci;

	dimm->dev.type = &dimm_attr_type;
	dimm->dev.bus = mci->bus;
	device_initialize(&dimm->dev);

	dimm->dev.parent = &mci->dev;
	if (mci->csbased)
		dev_set_name(&dimm->dev, "rank%d", index);
	else
		dev_set_name(&dimm->dev, "dimm%d", index);
	dev_set_drvdata(&dimm->dev, dimm);
	pm_runtime_forbid(&mci->dev);

	err =  device_add(&dimm->dev);

	edac_dbg(0, "creating rank/dimm device %s\n", dev_name(&dimm->dev));

	return err;
}

static void csrow_attr_release(struct device *dev)
{
	struct csrow_info *csrow = container_of(dev, struct csrow_info, dev);

	edac_dbg(1, "Releasing csrow device %s\n", dev_name(dev));
	kfree(csrow);
}

void edac_unregister_sysfs(struct mem_ctl_info *mci)
{
	edac_dbg(1, "Unregistering device %s\n", dev_name(&mci->dev));
	device_unregister(&mci->dev);
	bus_unregister(mci->bus);
	kfree(mci->bus->name);
}

/*
 * edac_pci_remove_sysfs
 *
 *	remove the controls and attributes for this EDAC PCI device
 */
void edac_pci_remove_sysfs(struct edac_pci_ctl_info *pci)
{
	edac_dbg(0, "index=%d\n", pci->pci_idx);

	/* Remove the symlink */
	sysfs_remove_link(&pci->kobj, EDAC_PCI_SYMLINK);

	/* remove this PCI instance's sysfs entries */
	edac_pci_unregister_sysfs_instance_kobj(pci);

	/* Call the main unregister function, which will determine
	 * if this 'pci' is the last instance.
	 * If it is, the main kobject will be unregistered as a result
	 */
	edac_dbg(0, "calling edac_pci_main_kobj_teardown()\n");
	edac_pci_main_kobj_teardown();
}

/*
 * edac_exit()
 *      module exit/termination function
 */
static void __exit edac_exit(void)
{
	edac_dbg(0, "\n");

	/* tear down the various subsystems */
	edac_workqueue_teardown();
	edac_mc_sysfs_exit();
	edac_debugfs_exit();
}

static void mc_attr_release(struct device *dev)
{
	/*
	 * There's no container structure here, as this is just the mci
	 * parent device, used to create the /sys/devices/mc sysfs node.
	 * So, there are no attributes on it.
	 */
	edac_dbg(1, "Releasing device %s\n", dev_name(dev));
	kfree(dev);
}

void edac_unregister_sysfs(struct mem_ctl_info *mci)
{
	struct bus_type *bus = mci->bus;
	const char *name = mci->bus->name;

	edac_dbg(1, "Unregistering device %s\n", dev_name(&mci->dev));
	device_unregister(&mci->dev);
	bus_unregister(bus);
	kfree(name);
}

/*
 * edac_pci_unregister_sysfs_instance_kobj
 *
 *	unregister the kobj for the EDAC PCI instance
 */
static void edac_pci_unregister_sysfs_instance_kobj(
			struct edac_pci_ctl_info *pci)
{
	edac_dbg(0, "\n");

	/* Unregister the instance kobject and allow its release
	 * function release the main reference count and then
	 * kfree the memory
	 */
	kobject_put(&pci->kobj);
}