WSL2-Linux-Kernel/drivers/greybus/core.c

350 строки
8.0 KiB
C

// 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>");