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path: root/drivers/gpu/host1x/bus.c
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Diffstat (limited to 'drivers/gpu/host1x/bus.c')
-rw-r--r--drivers/gpu/host1x/bus.c550
1 files changed, 550 insertions, 0 deletions
diff --git a/drivers/gpu/host1x/bus.c b/drivers/gpu/host1x/bus.c
new file mode 100644
index 000000000000..509383f8be03
--- /dev/null
+++ b/drivers/gpu/host1x/bus.c
@@ -0,0 +1,550 @@
+/*
+ * Copyright (C) 2012 Avionic Design GmbH
+ * Copyright (C) 2012-2013, NVIDIA Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/host1x.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+
+#include "dev.h"
+
+static DEFINE_MUTEX(clients_lock);
+static LIST_HEAD(clients);
+
+static DEFINE_MUTEX(drivers_lock);
+static LIST_HEAD(drivers);
+
+static DEFINE_MUTEX(devices_lock);
+static LIST_HEAD(devices);
+
+struct host1x_subdev {
+ struct host1x_client *client;
+ struct device_node *np;
+ struct list_head list;
+};
+
+/**
+ * host1x_subdev_add() - add a new subdevice with an associated device node
+ */
+static int host1x_subdev_add(struct host1x_device *device,
+ struct device_node *np)
+{
+ struct host1x_subdev *subdev;
+
+ subdev = kzalloc(sizeof(*subdev), GFP_KERNEL);
+ if (!subdev)
+ return -ENOMEM;
+
+ INIT_LIST_HEAD(&subdev->list);
+ subdev->np = of_node_get(np);
+
+ mutex_lock(&device->subdevs_lock);
+ list_add_tail(&subdev->list, &device->subdevs);
+ mutex_unlock(&device->subdevs_lock);
+
+ return 0;
+}
+
+/**
+ * host1x_subdev_del() - remove subdevice
+ */
+static void host1x_subdev_del(struct host1x_subdev *subdev)
+{
+ list_del(&subdev->list);
+ of_node_put(subdev->np);
+ kfree(subdev);
+}
+
+/**
+ * host1x_device_parse_dt() - scan device tree and add matching subdevices
+ */
+static int host1x_device_parse_dt(struct host1x_device *device)
+{
+ struct device_node *np;
+ int err;
+
+ for_each_child_of_node(device->dev.parent->of_node, np) {
+ if (of_match_node(device->driver->subdevs, np) &&
+ of_device_is_available(np)) {
+ err = host1x_subdev_add(device, np);
+ if (err < 0)
+ return err;
+ }
+ }
+
+ return 0;
+}
+
+static void host1x_subdev_register(struct host1x_device *device,
+ struct host1x_subdev *subdev,
+ struct host1x_client *client)
+{
+ int err;
+
+ /*
+ * Move the subdevice to the list of active (registered) subdevices
+ * and associate it with a client. At the same time, associate the
+ * client with its parent device.
+ */
+ mutex_lock(&device->subdevs_lock);
+ mutex_lock(&device->clients_lock);
+ list_move_tail(&client->list, &device->clients);
+ list_move_tail(&subdev->list, &device->active);
+ client->parent = &device->dev;
+ subdev->client = client;
+ mutex_unlock(&device->clients_lock);
+ mutex_unlock(&device->subdevs_lock);
+
+ /*
+ * When all subdevices have been registered, the composite device is
+ * ready to be probed.
+ */
+ if (list_empty(&device->subdevs)) {
+ err = device->driver->probe(device);
+ if (err < 0)
+ dev_err(&device->dev, "probe failed: %d\n", err);
+ }
+}
+
+static void __host1x_subdev_unregister(struct host1x_device *device,
+ struct host1x_subdev *subdev)
+{
+ struct host1x_client *client = subdev->client;
+ int err;
+
+ /*
+ * If all subdevices have been activated, we're about to remove the
+ * first active subdevice, so unload the driver first.
+ */
+ if (list_empty(&device->subdevs)) {
+ err = device->driver->remove(device);
+ if (err < 0)
+ dev_err(&device->dev, "remove failed: %d\n", err);
+ }
+
+ /*
+ * Move the subdevice back to the list of idle subdevices and remove
+ * it from list of clients.
+ */
+ mutex_lock(&device->clients_lock);
+ subdev->client = NULL;
+ client->parent = NULL;
+ list_move_tail(&subdev->list, &device->subdevs);
+ /*
+ * XXX: Perhaps don't do this here, but rather explicitly remove it
+ * when the device is about to be deleted.
+ *
+ * This is somewhat complicated by the fact that this function is
+ * used to remove the subdevice when a client is unregistered but
+ * also when the composite device is about to be removed.
+ */
+ list_del_init(&client->list);
+ mutex_unlock(&device->clients_lock);
+}
+
+static void host1x_subdev_unregister(struct host1x_device *device,
+ struct host1x_subdev *subdev)
+{
+ mutex_lock(&device->subdevs_lock);
+ __host1x_subdev_unregister(device, subdev);
+ mutex_unlock(&device->subdevs_lock);
+}
+
+int host1x_device_init(struct host1x_device *device)
+{
+ struct host1x_client *client;
+ int err;
+
+ mutex_lock(&device->clients_lock);
+
+ list_for_each_entry(client, &device->clients, list) {
+ if (client->ops && client->ops->init) {
+ err = client->ops->init(client);
+ if (err < 0) {
+ dev_err(&device->dev,
+ "failed to initialize %s: %d\n",
+ dev_name(client->dev), err);
+ mutex_unlock(&device->clients_lock);
+ return err;
+ }
+ }
+ }
+
+ mutex_unlock(&device->clients_lock);
+
+ return 0;
+}
+
+int host1x_device_exit(struct host1x_device *device)
+{
+ struct host1x_client *client;
+ int err;
+
+ mutex_lock(&device->clients_lock);
+
+ list_for_each_entry_reverse(client, &device->clients, list) {
+ if (client->ops && client->ops->exit) {
+ err = client->ops->exit(client);
+ if (err < 0) {
+ dev_err(&device->dev,
+ "failed to cleanup %s: %d\n",
+ dev_name(client->dev), err);
+ mutex_unlock(&device->clients_lock);
+ return err;
+ }
+ }
+ }
+
+ mutex_unlock(&device->clients_lock);
+
+ return 0;
+}
+
+static int host1x_register_client(struct host1x *host1x,
+ struct host1x_client *client)
+{
+ struct host1x_device *device;
+ struct host1x_subdev *subdev;
+
+ mutex_lock(&host1x->devices_lock);
+
+ list_for_each_entry(device, &host1x->devices, list) {
+ list_for_each_entry(subdev, &device->subdevs, list) {
+ if (subdev->np == client->dev->of_node) {
+ host1x_subdev_register(device, subdev, client);
+ mutex_unlock(&host1x->devices_lock);
+ return 0;
+ }
+ }
+ }
+
+ mutex_unlock(&host1x->devices_lock);
+ return -ENODEV;
+}
+
+static int host1x_unregister_client(struct host1x *host1x,
+ struct host1x_client *client)
+{
+ struct host1x_device *device, *dt;
+ struct host1x_subdev *subdev;
+
+ mutex_lock(&host1x->devices_lock);
+
+ list_for_each_entry_safe(device, dt, &host1x->devices, list) {
+ list_for_each_entry(subdev, &device->active, list) {
+ if (subdev->client == client) {
+ host1x_subdev_unregister(device, subdev);
+ mutex_unlock(&host1x->devices_lock);
+ return 0;
+ }
+ }
+ }
+
+ mutex_unlock(&host1x->devices_lock);
+ return -ENODEV;
+}
+
+struct bus_type host1x_bus_type = {
+ .name = "host1x",
+};
+
+int host1x_bus_init(void)
+{
+ return bus_register(&host1x_bus_type);
+}
+
+void host1x_bus_exit(void)
+{
+ bus_unregister(&host1x_bus_type);
+}
+
+static void host1x_device_release(struct device *dev)
+{
+ struct host1x_device *device = to_host1x_device(dev);
+
+ kfree(device);
+}
+
+static int host1x_device_add(struct host1x *host1x,
+ struct host1x_driver *driver)
+{
+ struct host1x_client *client, *tmp;
+ struct host1x_subdev *subdev;
+ struct host1x_device *device;
+ int err;
+
+ device = kzalloc(sizeof(*device), GFP_KERNEL);
+ if (!device)
+ return -ENOMEM;
+
+ mutex_init(&device->subdevs_lock);
+ INIT_LIST_HEAD(&device->subdevs);
+ INIT_LIST_HEAD(&device->active);
+ mutex_init(&device->clients_lock);
+ INIT_LIST_HEAD(&device->clients);
+ INIT_LIST_HEAD(&device->list);
+ device->driver = driver;
+
+ device->dev.coherent_dma_mask = host1x->dev->coherent_dma_mask;
+ device->dev.dma_mask = &device->dev.coherent_dma_mask;
+ device->dev.release = host1x_device_release;
+ dev_set_name(&device->dev, driver->name);
+ device->dev.bus = &host1x_bus_type;
+ device->dev.parent = host1x->dev;
+
+ err = device_register(&device->dev);
+ if (err < 0)
+ return err;
+
+ err = host1x_device_parse_dt(device);
+ if (err < 0) {
+ device_unregister(&device->dev);
+ return err;
+ }
+
+ mutex_lock(&host1x->devices_lock);
+ list_add_tail(&device->list, &host1x->devices);
+ mutex_unlock(&host1x->devices_lock);
+
+ mutex_lock(&clients_lock);
+
+ list_for_each_entry_safe(client, tmp, &clients, list) {
+ list_for_each_entry(subdev, &device->subdevs, list) {
+ if (subdev->np == client->dev->of_node) {
+ host1x_subdev_register(device, subdev, client);
+ break;
+ }
+ }
+ }
+
+ mutex_unlock(&clients_lock);
+
+ return 0;
+}
+
+/*
+ * Removes a device by first unregistering any subdevices and then removing
+ * itself from the list of devices.
+ *
+ * This function must be called with the host1x->devices_lock held.
+ */
+static void host1x_device_del(struct host1x *host1x,
+ struct host1x_device *device)
+{
+ struct host1x_subdev *subdev, *sd;
+ struct host1x_client *client, *cl;
+
+ mutex_lock(&device->subdevs_lock);
+
+ /* unregister subdevices */
+ list_for_each_entry_safe(subdev, sd, &device->active, list) {
+ /*
+ * host1x_subdev_unregister() will remove the client from
+ * any lists, so we'll need to manually add it back to the
+ * list of idle clients.
+ *
+ * XXX: Alternatively, perhaps don't remove the client from
+ * any lists in host1x_subdev_unregister() and instead do
+ * that explicitly from host1x_unregister_client()?
+ */
+ client = subdev->client;
+
+ __host1x_subdev_unregister(device, subdev);
+
+ /* add the client to the list of idle clients */
+ mutex_lock(&clients_lock);
+ list_add_tail(&client->list, &clients);
+ mutex_unlock(&clients_lock);
+ }
+
+ /* remove subdevices */
+ list_for_each_entry_safe(subdev, sd, &device->subdevs, list)
+ host1x_subdev_del(subdev);
+
+ mutex_unlock(&device->subdevs_lock);
+
+ /* move clients to idle list */
+ mutex_lock(&clients_lock);
+ mutex_lock(&device->clients_lock);
+
+ list_for_each_entry_safe(client, cl, &device->clients, list)
+ list_move_tail(&client->list, &clients);
+
+ mutex_unlock(&device->clients_lock);
+ mutex_unlock(&clients_lock);
+
+ /* finally remove the device */
+ list_del_init(&device->list);
+ device_unregister(&device->dev);
+}
+
+static void host1x_attach_driver(struct host1x *host1x,
+ struct host1x_driver *driver)
+{
+ struct host1x_device *device;
+ int err;
+
+ mutex_lock(&host1x->devices_lock);
+
+ list_for_each_entry(device, &host1x->devices, list) {
+ if (device->driver == driver) {
+ mutex_unlock(&host1x->devices_lock);
+ return;
+ }
+ }
+
+ mutex_unlock(&host1x->devices_lock);
+
+ err = host1x_device_add(host1x, driver);
+ if (err < 0)
+ dev_err(host1x->dev, "failed to allocate device: %d\n", err);
+}
+
+static void host1x_detach_driver(struct host1x *host1x,
+ struct host1x_driver *driver)
+{
+ struct host1x_device *device, *tmp;
+
+ mutex_lock(&host1x->devices_lock);
+
+ list_for_each_entry_safe(device, tmp, &host1x->devices, list)
+ if (device->driver == driver)
+ host1x_device_del(host1x, device);
+
+ mutex_unlock(&host1x->devices_lock);
+}
+
+int host1x_register(struct host1x *host1x)
+{
+ struct host1x_driver *driver;
+
+ mutex_lock(&devices_lock);
+ list_add_tail(&host1x->list, &devices);
+ mutex_unlock(&devices_lock);
+
+ mutex_lock(&drivers_lock);
+
+ list_for_each_entry(driver, &drivers, list)
+ host1x_attach_driver(host1x, driver);
+
+ mutex_unlock(&drivers_lock);
+
+ return 0;
+}
+
+int host1x_unregister(struct host1x *host1x)
+{
+ struct host1x_driver *driver;
+
+ mutex_lock(&drivers_lock);
+
+ list_for_each_entry(driver, &drivers, list)
+ host1x_detach_driver(host1x, driver);
+
+ mutex_unlock(&drivers_lock);
+
+ mutex_lock(&devices_lock);
+ list_del_init(&host1x->list);
+ mutex_unlock(&devices_lock);
+
+ return 0;
+}
+
+int host1x_driver_register(struct host1x_driver *driver)
+{
+ struct host1x *host1x;
+
+ INIT_LIST_HEAD(&driver->list);
+
+ mutex_lock(&drivers_lock);
+ list_add_tail(&driver->list, &drivers);
+ mutex_unlock(&drivers_lock);
+
+ mutex_lock(&devices_lock);
+
+ list_for_each_entry(host1x, &devices, list)
+ host1x_attach_driver(host1x, driver);
+
+ mutex_unlock(&devices_lock);
+
+ return 0;
+}
+EXPORT_SYMBOL(host1x_driver_register);
+
+void host1x_driver_unregister(struct host1x_driver *driver)
+{
+ mutex_lock(&drivers_lock);
+ list_del_init(&driver->list);
+ mutex_unlock(&drivers_lock);
+}
+EXPORT_SYMBOL(host1x_driver_unregister);
+
+int host1x_client_register(struct host1x_client *client)
+{
+ struct host1x *host1x;
+ int err;
+
+ mutex_lock(&devices_lock);
+
+ list_for_each_entry(host1x, &devices, list) {
+ err = host1x_register_client(host1x, client);
+ if (!err) {
+ mutex_unlock(&devices_lock);
+ return 0;
+ }
+ }
+
+ mutex_unlock(&devices_lock);
+
+ mutex_lock(&clients_lock);
+ list_add_tail(&client->list, &clients);
+ mutex_unlock(&clients_lock);
+
+ return 0;
+}
+EXPORT_SYMBOL(host1x_client_register);
+
+int host1x_client_unregister(struct host1x_client *client)
+{
+ struct host1x_client *c;
+ struct host1x *host1x;
+ int err;
+
+ mutex_lock(&devices_lock);
+
+ list_for_each_entry(host1x, &devices, list) {
+ err = host1x_unregister_client(host1x, client);
+ if (!err) {
+ mutex_unlock(&devices_lock);
+ return 0;
+ }
+ }
+
+ mutex_unlock(&devices_lock);
+ mutex_lock(&clients_lock);
+
+ list_for_each_entry(c, &clients, list) {
+ if (c == client) {
+ list_del_init(&c->list);
+ break;
+ }
+ }
+
+ mutex_unlock(&clients_lock);
+
+ return 0;
+}
+EXPORT_SYMBOL(host1x_client_unregister);