Fixed MTP to work with TWRP

drivers/dca/Kconfig

@@ -0,0 +1,7 @@
+#
+# DCA server configuration
+#
+
+config DCA
+	tristate
+

drivers/dca/Makefile

@@ -0,0 +1,2 @@
+obj-$(CONFIG_DCA) += dca.o
+dca-objs := dca-core.o dca-sysfs.o

drivers/dca/dca-core.c

@@ -0,0 +1,472 @@
+/*
+ * Copyright(c) 2007 - 2009 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59
+ * Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ *
+ * The full GNU General Public License is included in this distribution in the
+ * file called COPYING.
+ */
+
+/*
+ * This driver supports an interface for DCA clients and providers to meet.
+ */
+
+#include <linux/kernel.h>
+#include <linux/notifier.h>
+#include <linux/device.h>
+#include <linux/dca.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+
+#define DCA_VERSION "1.12.1"
+
+MODULE_VERSION(DCA_VERSION);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Intel Corporation");
+
+static DEFINE_RAW_SPINLOCK(dca_lock);
+
+static LIST_HEAD(dca_domains);
+
+static BLOCKING_NOTIFIER_HEAD(dca_provider_chain);
+
+static int dca_providers_blocked;
+
+static struct pci_bus *dca_pci_rc_from_dev(struct device *dev)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+	struct pci_bus *bus = pdev->bus;
+
+	while (bus->parent)
+		bus = bus->parent;
+
+	return bus;
+}
+
+static struct dca_domain *dca_allocate_domain(struct pci_bus *rc)
+{
+	struct dca_domain *domain;
+
+	domain = kzalloc(sizeof(*domain), GFP_NOWAIT);
+	if (!domain)
+		return NULL;
+
+	INIT_LIST_HEAD(&domain->dca_providers);
+	domain->pci_rc = rc;
+
+	return domain;
+}
+
+static void dca_free_domain(struct dca_domain *domain)
+{
+	list_del(&domain->node);
+	kfree(domain);
+}
+
+static int dca_provider_ioat_ver_3_0(struct device *dev)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+
+	return ((pdev->vendor == PCI_VENDOR_ID_INTEL) &&
+		((pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG0) ||
+		(pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG1) ||
+		(pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG2) ||
+		(pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG3) ||
+		(pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG4) ||
+		(pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG5) ||
+		(pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG6) ||
+		(pdev->device == PCI_DEVICE_ID_INTEL_IOAT_TBG7)));
+}
+
+static void unregister_dca_providers(void)
+{
+	struct dca_provider *dca, *_dca;
+	struct list_head unregistered_providers;
+	struct dca_domain *domain;
+	unsigned long flags;
+
+	blocking_notifier_call_chain(&dca_provider_chain,
+				     DCA_PROVIDER_REMOVE, NULL);
+
+	INIT_LIST_HEAD(&unregistered_providers);
+
+	raw_spin_lock_irqsave(&dca_lock, flags);
+
+	if (list_empty(&dca_domains)) {
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
+		return;
+	}
+
+	/* at this point only one domain in the list is expected */
+	domain = list_first_entry(&dca_domains, struct dca_domain, node);
+
+	list_for_each_entry_safe(dca, _dca, &domain->dca_providers, node)
+		list_move(&dca->node, &unregistered_providers);
+
+	dca_free_domain(domain);
+
+	raw_spin_unlock_irqrestore(&dca_lock, flags);
+
+	list_for_each_entry_safe(dca, _dca, &unregistered_providers, node) {
+		dca_sysfs_remove_provider(dca);
+		list_del(&dca->node);
+	}
+}
+
+static struct dca_domain *dca_find_domain(struct pci_bus *rc)
+{
+	struct dca_domain *domain;
+
+	list_for_each_entry(domain, &dca_domains, node)
+		if (domain->pci_rc == rc)
+			return domain;
+
+	return NULL;
+}
+
+static struct dca_domain *dca_get_domain(struct device *dev)
+{
+	struct pci_bus *rc;
+	struct dca_domain *domain;
+
+	rc = dca_pci_rc_from_dev(dev);
+	domain = dca_find_domain(rc);
+
+	if (!domain) {
+		if (dca_provider_ioat_ver_3_0(dev) && !list_empty(&dca_domains))
+			dca_providers_blocked = 1;
+	}
+
+	return domain;
+}
+
+static struct dca_provider *dca_find_provider_by_dev(struct device *dev)
+{
+	struct dca_provider *dca;
+	struct pci_bus *rc;
+	struct dca_domain *domain;
+
+	if (dev) {
+		rc = dca_pci_rc_from_dev(dev);
+		domain = dca_find_domain(rc);
+		if (!domain)
+			return NULL;
+	} else {
+		if (!list_empty(&dca_domains))
+			domain = list_first_entry(&dca_domains,
+						  struct dca_domain,
+						  node);
+		else
+			return NULL;
+	}
+
+	list_for_each_entry(dca, &domain->dca_providers, node)
+		if ((!dev) || (dca->ops->dev_managed(dca, dev)))
+			return dca;
+
+	return NULL;
+}
+
+/**
+ * dca_add_requester - add a dca client to the list
+ * @dev - the device that wants dca service
+ */
+int dca_add_requester(struct device *dev)
+{
+	struct dca_provider *dca;
+	int err, slot = -ENODEV;
+	unsigned long flags;
+	struct pci_bus *pci_rc;
+	struct dca_domain *domain;
+
+	if (!dev)
+		return -EFAULT;
+
+	raw_spin_lock_irqsave(&dca_lock, flags);
+
+	/* check if the requester has not been added already */
+	dca = dca_find_provider_by_dev(dev);
+	if (dca) {
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
+		return -EEXIST;
+	}
+
+	pci_rc = dca_pci_rc_from_dev(dev);
+	domain = dca_find_domain(pci_rc);
+	if (!domain) {
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
+		return -ENODEV;
+	}
+
+	list_for_each_entry(dca, &domain->dca_providers, node) {
+		slot = dca->ops->add_requester(dca, dev);
+		if (slot >= 0)
+			break;
+	}
+
+	raw_spin_unlock_irqrestore(&dca_lock, flags);
+
+	if (slot < 0)
+		return slot;
+
+	err = dca_sysfs_add_req(dca, dev, slot);
+	if (err) {
+		raw_spin_lock_irqsave(&dca_lock, flags);
+		if (dca == dca_find_provider_by_dev(dev))
+			dca->ops->remove_requester(dca, dev);
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
+		return err;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(dca_add_requester);
+
+/**
+ * dca_remove_requester - remove a dca client from the list
+ * @dev - the device that wants dca service
+ */
+int dca_remove_requester(struct device *dev)
+{
+	struct dca_provider *dca;
+	int slot;
+	unsigned long flags;
+
+	if (!dev)
+		return -EFAULT;
+
+	raw_spin_lock_irqsave(&dca_lock, flags);
+	dca = dca_find_provider_by_dev(dev);
+	if (!dca) {
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
+		return -ENODEV;
+	}
+	slot = dca->ops->remove_requester(dca, dev);
+	raw_spin_unlock_irqrestore(&dca_lock, flags);
+
+	if (slot < 0)
+		return slot;
+
+	dca_sysfs_remove_req(dca, slot);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(dca_remove_requester);
+
+/**
+ * dca_common_get_tag - return the dca tag (serves both new and old api)
+ * @dev - the device that wants dca service
+ * @cpu - the cpuid as returned by get_cpu()
+ */
+u8 dca_common_get_tag(struct device *dev, int cpu)
+{
+	struct dca_provider *dca;
+	u8 tag;
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&dca_lock, flags);
+
+	dca = dca_find_provider_by_dev(dev);
+	if (!dca) {
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
+		return -ENODEV;
+	}
+	tag = dca->ops->get_tag(dca, dev, cpu);
+
+	raw_spin_unlock_irqrestore(&dca_lock, flags);
+	return tag;
+}
+
+/**
+ * dca3_get_tag - return the dca tag to the requester device
+ *                for the given cpu (new api)
+ * @dev - the device that wants dca service
+ * @cpu - the cpuid as returned by get_cpu()
+ */
+u8 dca3_get_tag(struct device *dev, int cpu)
+{
+	if (!dev)
+		return -EFAULT;
+
+	return dca_common_get_tag(dev, cpu);
+}
+EXPORT_SYMBOL_GPL(dca3_get_tag);
+
+/**
+ * dca_get_tag - return the dca tag for the given cpu (old api)
+ * @cpu - the cpuid as returned by get_cpu()
+ */
+u8 dca_get_tag(int cpu)
+{
+	struct device *dev = NULL;
+
+	return dca_common_get_tag(dev, cpu);
+}
+EXPORT_SYMBOL_GPL(dca_get_tag);
+
+/**
+ * alloc_dca_provider - get data struct for describing a dca provider
+ * @ops - pointer to struct of dca operation function pointers
+ * @priv_size - size of extra mem to be added for provider's needs
+ */
+struct dca_provider *alloc_dca_provider(struct dca_ops *ops, int priv_size)
+{
+	struct dca_provider *dca;
+	int alloc_size;
+
+	alloc_size = (sizeof(*dca) + priv_size);
+	dca = kzalloc(alloc_size, GFP_KERNEL);
+	if (!dca)
+		return NULL;
+	dca->ops = ops;
+
+	return dca;
+}
+EXPORT_SYMBOL_GPL(alloc_dca_provider);
+
+/**
+ * free_dca_provider - release the dca provider data struct
+ * @ops - pointer to struct of dca operation function pointers
+ * @priv_size - size of extra mem to be added for provider's needs
+ */
+void free_dca_provider(struct dca_provider *dca)
+{
+	kfree(dca);
+}
+EXPORT_SYMBOL_GPL(free_dca_provider);
+
+/**
+ * register_dca_provider - register a dca provider
+ * @dca - struct created by alloc_dca_provider()
+ * @dev - device providing dca services
+ */
+int register_dca_provider(struct dca_provider *dca, struct device *dev)
+{
+	int err;
+	unsigned long flags;
+	struct dca_domain *domain, *newdomain = NULL;
+
+	raw_spin_lock_irqsave(&dca_lock, flags);
+	if (dca_providers_blocked) {
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
+		return -ENODEV;
+	}
+	raw_spin_unlock_irqrestore(&dca_lock, flags);
+
+	err = dca_sysfs_add_provider(dca, dev);
+	if (err)
+		return err;
+
+	raw_spin_lock_irqsave(&dca_lock, flags);
+	domain = dca_get_domain(dev);
+	if (!domain) {
+		struct pci_bus *rc;
+
+		if (dca_providers_blocked) {
+			raw_spin_unlock_irqrestore(&dca_lock, flags);
+			dca_sysfs_remove_provider(dca);
+			unregister_dca_providers();
+			return -ENODEV;
+		}
+
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
+		rc = dca_pci_rc_from_dev(dev);
+		newdomain = dca_allocate_domain(rc);
+		if (!newdomain)
+			return -ENODEV;
+		raw_spin_lock_irqsave(&dca_lock, flags);
+		/* Recheck, we might have raced after dropping the lock */
+		domain = dca_get_domain(dev);
+		if (!domain) {
+			domain = newdomain;
+			newdomain = NULL;
+			list_add(&domain->node, &dca_domains);
+		}
+	}
+	list_add(&dca->node, &domain->dca_providers);
+	raw_spin_unlock_irqrestore(&dca_lock, flags);
+
+	blocking_notifier_call_chain(&dca_provider_chain,
+				     DCA_PROVIDER_ADD, NULL);
+	kfree(newdomain);
+	return 0;
+}
+EXPORT_SYMBOL_GPL(register_dca_provider);
+
+/**
+ * unregister_dca_provider - remove a dca provider
+ * @dca - struct created by alloc_dca_provider()
+ */
+void unregister_dca_provider(struct dca_provider *dca, struct device *dev)
+{
+	unsigned long flags;
+	struct pci_bus *pci_rc;
+	struct dca_domain *domain;
+
+	blocking_notifier_call_chain(&dca_provider_chain,
+				     DCA_PROVIDER_REMOVE, NULL);
+
+	raw_spin_lock_irqsave(&dca_lock, flags);
+
+	if (list_empty(&dca_domains)) {
+		raw_spin_unlock_irqrestore(&dca_lock, flags);
+		return;
+	}
+
+	list_del(&dca->node);
+
+	pci_rc = dca_pci_rc_from_dev(dev);
+	domain = dca_find_domain(pci_rc);
+	if (list_empty(&domain->dca_providers))
+		dca_free_domain(domain);
+
+	raw_spin_unlock_irqrestore(&dca_lock, flags);
+
+	dca_sysfs_remove_provider(dca);
+}
+EXPORT_SYMBOL_GPL(unregister_dca_provider);
+
+/**
+ * dca_register_notify - register a client's notifier callback
+ */
+void dca_register_notify(struct notifier_block *nb)
+{
+	blocking_notifier_chain_register(&dca_provider_chain, nb);
+}
+EXPORT_SYMBOL_GPL(dca_register_notify);
+
+/**
+ * dca_unregister_notify - remove a client's notifier callback
+ */
+void dca_unregister_notify(struct notifier_block *nb)
+{
+	blocking_notifier_chain_unregister(&dca_provider_chain, nb);
+}
+EXPORT_SYMBOL_GPL(dca_unregister_notify);
+
+static int __init dca_init(void)
+{
+	pr_info("dca service started, version %s\n", DCA_VERSION);
+	return dca_sysfs_init();
+}
+
+static void __exit dca_exit(void)
+{
+	dca_sysfs_exit();
+}
+
+arch_initcall(dca_init);
+module_exit(dca_exit);
+

drivers/dca/dca-sysfs.c

@@ -0,0 +1,108 @@
+/*
+ * Copyright(c) 2007 - 2009 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59
+ * Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ *
+ * The full GNU General Public License is included in this distribution in the
+ * file called COPYING.
+ */
+
+#include <linux/kernel.h>
+#include <linux/spinlock.h>
+#include <linux/device.h>
+#include <linux/idr.h>
+#include <linux/kdev_t.h>
+#include <linux/err.h>
+#include <linux/dca.h>
+#include <linux/gfp.h>
+#include <linux/export.h>
+
+static struct class *dca_class;
+static struct idr dca_idr;
+static spinlock_t dca_idr_lock;
+
+int dca_sysfs_add_req(struct dca_provider *dca, struct device *dev, int slot)
+{
+	struct device *cd;
+	static int req_count;
+
+	cd = device_create(dca_class, dca->cd, MKDEV(0, slot + 1), NULL,
+			   "requester%d", req_count++);
+	if (IS_ERR(cd))
+		return PTR_ERR(cd);
+	return 0;
+}
+
+void dca_sysfs_remove_req(struct dca_provider *dca, int slot)
+{
+	device_destroy(dca_class, MKDEV(0, slot + 1));
+}
+
+int dca_sysfs_add_provider(struct dca_provider *dca, struct device *dev)
+{
+	struct device *cd;
+	int ret;
+
+	idr_preload(GFP_KERNEL);
+	spin_lock(&dca_idr_lock);
+
+	ret = idr_alloc(&dca_idr, dca, 0, 0, GFP_NOWAIT);
+	if (ret >= 0)
+		dca->id = ret;
+
+	spin_unlock(&dca_idr_lock);
+	idr_preload_end();
+	if (ret < 0)
+		return ret;
+
+	cd = device_create(dca_class, dev, MKDEV(0, 0), NULL, "dca%d", dca->id);
+	if (IS_ERR(cd)) {
+		spin_lock(&dca_idr_lock);
+		idr_remove(&dca_idr, dca->id);
+		spin_unlock(&dca_idr_lock);
+		return PTR_ERR(cd);
+	}
+	dca->cd = cd;
+	return 0;
+}
+
+void dca_sysfs_remove_provider(struct dca_provider *dca)
+{
+	device_unregister(dca->cd);
+	dca->cd = NULL;
+	spin_lock(&dca_idr_lock);
+	idr_remove(&dca_idr, dca->id);
+	spin_unlock(&dca_idr_lock);
+}
+
+int __init dca_sysfs_init(void)
+{
+	idr_init(&dca_idr);
+	spin_lock_init(&dca_idr_lock);
+
+	dca_class = class_create(THIS_MODULE, "dca");
+	if (IS_ERR(dca_class)) {
+		idr_destroy(&dca_idr);
+		return PTR_ERR(dca_class);
+	}
+	return 0;
+}
+
+void __exit dca_sysfs_exit(void)
+{
+	class_destroy(dca_class);
+	idr_destroy(&dca_idr);
+}
+