summaryrefslogtreecommitdiffstats
path: root/drivers/greybus/core.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/greybus/core.c')
-rw-r--r--drivers/greybus/core.c349
1 files changed, 349 insertions, 0 deletions
diff --git a/drivers/greybus/core.c b/drivers/greybus/core.c
new file mode 100644
index 000000000..e546c6431
--- /dev/null
+++ b/drivers/greybus/core.c
@@ -0,0 +1,349 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Greybus "Core"
+ *
+ * Copyright 2014-2015 Google Inc.
+ * Copyright 2014-2015 Linaro Ltd.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#define CREATE_TRACE_POINTS
+#include <linux/greybus.h>
+#include "greybus_trace.h"
+
+#define GB_BUNDLE_AUTOSUSPEND_MS 3000
+
+/* Allow greybus to be disabled at boot if needed */
+static bool nogreybus;
+#ifdef MODULE
+module_param(nogreybus, bool, 0444);
+#else
+core_param(nogreybus, nogreybus, bool, 0444);
+#endif
+int greybus_disabled(void)
+{
+ return nogreybus;
+}
+EXPORT_SYMBOL_GPL(greybus_disabled);
+
+static bool greybus_match_one_id(struct gb_bundle *bundle,
+ const struct greybus_bundle_id *id)
+{
+ if ((id->match_flags & GREYBUS_ID_MATCH_VENDOR) &&
+ (id->vendor != bundle->intf->vendor_id))
+ return false;
+
+ if ((id->match_flags & GREYBUS_ID_MATCH_PRODUCT) &&
+ (id->product != bundle->intf->product_id))
+ return false;
+
+ if ((id->match_flags & GREYBUS_ID_MATCH_CLASS) &&
+ (id->class != bundle->class))
+ return false;
+
+ return true;
+}
+
+static const struct greybus_bundle_id *
+greybus_match_id(struct gb_bundle *bundle, const struct greybus_bundle_id *id)
+{
+ if (!id)
+ return NULL;
+
+ for (; id->vendor || id->product || id->class || id->driver_info;
+ id++) {
+ if (greybus_match_one_id(bundle, id))
+ return id;
+ }
+
+ return NULL;
+}
+
+static int greybus_match_device(struct device *dev, struct device_driver *drv)
+{
+ struct greybus_driver *driver = to_greybus_driver(drv);
+ struct gb_bundle *bundle;
+ const struct greybus_bundle_id *id;
+
+ if (!is_gb_bundle(dev))
+ return 0;
+
+ bundle = to_gb_bundle(dev);
+
+ id = greybus_match_id(bundle, driver->id_table);
+ if (id)
+ return 1;
+ /* FIXME - Dynamic ids? */
+ return 0;
+}
+
+static int greybus_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+ struct gb_host_device *hd;
+ struct gb_module *module = NULL;
+ struct gb_interface *intf = NULL;
+ struct gb_control *control = NULL;
+ struct gb_bundle *bundle = NULL;
+ struct gb_svc *svc = NULL;
+
+ if (is_gb_host_device(dev)) {
+ hd = to_gb_host_device(dev);
+ } else if (is_gb_module(dev)) {
+ module = to_gb_module(dev);
+ hd = module->hd;
+ } else if (is_gb_interface(dev)) {
+ intf = to_gb_interface(dev);
+ module = intf->module;
+ hd = intf->hd;
+ } else if (is_gb_control(dev)) {
+ control = to_gb_control(dev);
+ intf = control->intf;
+ module = intf->module;
+ hd = intf->hd;
+ } else if (is_gb_bundle(dev)) {
+ bundle = to_gb_bundle(dev);
+ intf = bundle->intf;
+ module = intf->module;
+ hd = intf->hd;
+ } else if (is_gb_svc(dev)) {
+ svc = to_gb_svc(dev);
+ hd = svc->hd;
+ } else {
+ dev_WARN(dev, "uevent for unknown greybus device \"type\"!\n");
+ return -EINVAL;
+ }
+
+ if (add_uevent_var(env, "BUS=%u", hd->bus_id))
+ return -ENOMEM;
+
+ if (module) {
+ if (add_uevent_var(env, "MODULE=%u", module->module_id))
+ return -ENOMEM;
+ }
+
+ if (intf) {
+ if (add_uevent_var(env, "INTERFACE=%u", intf->interface_id))
+ return -ENOMEM;
+ if (add_uevent_var(env, "GREYBUS_ID=%08x/%08x",
+ intf->vendor_id, intf->product_id))
+ return -ENOMEM;
+ }
+
+ if (bundle) {
+ // FIXME
+ // add a uevent that can "load" a bundle type
+ // This is what we need to bind a driver to so use the info
+ // in gmod here as well
+
+ if (add_uevent_var(env, "BUNDLE=%u", bundle->id))
+ return -ENOMEM;
+ if (add_uevent_var(env, "BUNDLE_CLASS=%02x", bundle->class))
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+static void greybus_shutdown(struct device *dev)
+{
+ if (is_gb_host_device(dev)) {
+ struct gb_host_device *hd;
+
+ hd = to_gb_host_device(dev);
+ gb_hd_shutdown(hd);
+ }
+}
+
+struct bus_type greybus_bus_type = {
+ .name = "greybus",
+ .match = greybus_match_device,
+ .uevent = greybus_uevent,
+ .shutdown = greybus_shutdown,
+};
+
+static int greybus_probe(struct device *dev)
+{
+ struct greybus_driver *driver = to_greybus_driver(dev->driver);
+ struct gb_bundle *bundle = to_gb_bundle(dev);
+ const struct greybus_bundle_id *id;
+ int retval;
+
+ /* match id */
+ id = greybus_match_id(bundle, driver->id_table);
+ if (!id)
+ return -ENODEV;
+
+ retval = pm_runtime_get_sync(&bundle->intf->dev);
+ if (retval < 0) {
+ pm_runtime_put_noidle(&bundle->intf->dev);
+ return retval;
+ }
+
+ retval = gb_control_bundle_activate(bundle->intf->control, bundle->id);
+ if (retval) {
+ pm_runtime_put(&bundle->intf->dev);
+ return retval;
+ }
+
+ /*
+ * Unbound bundle devices are always deactivated. During probe, the
+ * Runtime PM is set to enabled and active and the usage count is
+ * incremented. If the driver supports runtime PM, it should call
+ * pm_runtime_put() in its probe routine and pm_runtime_get_sync()
+ * in remove routine.
+ */
+ pm_runtime_set_autosuspend_delay(dev, GB_BUNDLE_AUTOSUSPEND_MS);
+ pm_runtime_use_autosuspend(dev);
+ pm_runtime_get_noresume(dev);
+ pm_runtime_set_active(dev);
+ pm_runtime_enable(dev);
+
+ retval = driver->probe(bundle, id);
+ if (retval) {
+ /*
+ * Catch buggy drivers that fail to destroy their connections.
+ */
+ WARN_ON(!list_empty(&bundle->connections));
+
+ gb_control_bundle_deactivate(bundle->intf->control, bundle->id);
+
+ pm_runtime_disable(dev);
+ pm_runtime_set_suspended(dev);
+ pm_runtime_put_noidle(dev);
+ pm_runtime_dont_use_autosuspend(dev);
+ pm_runtime_put(&bundle->intf->dev);
+
+ return retval;
+ }
+
+ pm_runtime_put(&bundle->intf->dev);
+
+ return 0;
+}
+
+static int greybus_remove(struct device *dev)
+{
+ struct greybus_driver *driver = to_greybus_driver(dev->driver);
+ struct gb_bundle *bundle = to_gb_bundle(dev);
+ struct gb_connection *connection;
+ int retval;
+
+ retval = pm_runtime_get_sync(dev);
+ if (retval < 0)
+ dev_err(dev, "failed to resume bundle: %d\n", retval);
+
+ /*
+ * Disable (non-offloaded) connections early in case the interface is
+ * already gone to avoid unceccessary operation timeouts during
+ * driver disconnect. Otherwise, only disable incoming requests.
+ */
+ list_for_each_entry(connection, &bundle->connections, bundle_links) {
+ if (gb_connection_is_offloaded(connection))
+ continue;
+
+ if (bundle->intf->disconnected)
+ gb_connection_disable_forced(connection);
+ else
+ gb_connection_disable_rx(connection);
+ }
+
+ driver->disconnect(bundle);
+
+ /* Catch buggy drivers that fail to destroy their connections. */
+ WARN_ON(!list_empty(&bundle->connections));
+
+ if (!bundle->intf->disconnected)
+ gb_control_bundle_deactivate(bundle->intf->control, bundle->id);
+
+ pm_runtime_put_noidle(dev);
+ pm_runtime_disable(dev);
+ pm_runtime_set_suspended(dev);
+ pm_runtime_dont_use_autosuspend(dev);
+ pm_runtime_put_noidle(dev);
+
+ return 0;
+}
+
+int greybus_register_driver(struct greybus_driver *driver, struct module *owner,
+ const char *mod_name)
+{
+ int retval;
+
+ if (greybus_disabled())
+ return -ENODEV;
+
+ driver->driver.bus = &greybus_bus_type;
+ driver->driver.name = driver->name;
+ driver->driver.probe = greybus_probe;
+ driver->driver.remove = greybus_remove;
+ driver->driver.owner = owner;
+ driver->driver.mod_name = mod_name;
+
+ retval = driver_register(&driver->driver);
+ if (retval)
+ return retval;
+
+ pr_info("registered new driver %s\n", driver->name);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(greybus_register_driver);
+
+void greybus_deregister_driver(struct greybus_driver *driver)
+{
+ driver_unregister(&driver->driver);
+}
+EXPORT_SYMBOL_GPL(greybus_deregister_driver);
+
+static int __init gb_init(void)
+{
+ int retval;
+
+ if (greybus_disabled())
+ return -ENODEV;
+
+ BUILD_BUG_ON(CPORT_ID_MAX >= (long)CPORT_ID_BAD);
+
+ gb_debugfs_init();
+
+ retval = bus_register(&greybus_bus_type);
+ if (retval) {
+ pr_err("bus_register failed (%d)\n", retval);
+ goto error_bus;
+ }
+
+ retval = gb_hd_init();
+ if (retval) {
+ pr_err("gb_hd_init failed (%d)\n", retval);
+ goto error_hd;
+ }
+
+ retval = gb_operation_init();
+ if (retval) {
+ pr_err("gb_operation_init failed (%d)\n", retval);
+ goto error_operation;
+ }
+ return 0; /* Success */
+
+error_operation:
+ gb_hd_exit();
+error_hd:
+ bus_unregister(&greybus_bus_type);
+error_bus:
+ gb_debugfs_cleanup();
+
+ return retval;
+}
+module_init(gb_init);
+
+static void __exit gb_exit(void)
+{
+ gb_operation_exit();
+ gb_hd_exit();
+ bus_unregister(&greybus_bus_type);
+ gb_debugfs_cleanup();
+ tracepoint_synchronize_unregister();
+}
+module_exit(gb_exit);
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Greg Kroah-Hartman <gregkh@linuxfoundation.org>");