From 8db00736d365b75d6af5dfd4a2673a1453fff4b7 Mon Sep 17 00:00:00 2001 From: Svetlin Ankov Date: Wed, 13 Jan 2016 14:07:48 -0700 Subject: [PATCH] greybus: audio: Add Audio Manager This is a simple module that keeps a list of connected GB audio modules. Whenever a device is attached, an appropriate uevent is sent to userspace: UDEV [4941.803215] add /kernel/gb_audio_manager/0 (gb_audio_manager) ACTION=add CPORT=99 DEVICES=0x10 DEVPATH=/kernel/gb_audio_manager/0 NAME=naim PID=64 SEQNUM=1828 SLOT=2 SUBSYSTEM=gb_audio_manager USEC_INITIALIZED=802416 VID=128 And whenever removed: UDEV [4941.836588] remove /kernel/gb_audio_manager/0 (gb_audio_manager) ACTION=remove DEVPATH=/kernel/gb_audio_manager/0 SEQNUM=1833 SUBSYSTEM=gb_audio_manager USEC_INITIALIZED=835681 The API consists of functions for adding, removing and inspecting added device module descriptions (struct gb_audio_module): int gb_audio_manager_add(struct gb_audio_module_descriptor *desc); int gb_audio_manager_remove(int id); int gb_audio_manager_remove_all(void); struct gb_audio_module* gb_audio_manager_get_module(int id); void gb_audio_manager_put_module(struct gb_audio_module *module); int gb_audio_manager_dump_module(int id); void gb_audio_manager_dump_all(void); Devices can be inspected through sysfs in /sys/kernel/gb_audio_manager/{id}/* If GB_AUDIO_MANAGER_SYSFS is exported as 'true', managing devices can be done via the SYSFS as well. For instance: echo name=naim slot=2 vid=128 pid=64 cport=99 devices=0x10 > /sys/kernel/gb_audio_manager/add echo all > /sys/kernel/gb_audio_manager/dump echo 2 > /sys/kernel/gb_audio_manager/dump echo 2 > /sys/kernel/gb_audio_manager/remove Signed-off-by: Svetlin Ankov Signed-off-by: Mark Greer Signed-off-by: Greg Kroah-Hartman --- drivers/staging/greybus/Makefile | 9 + drivers/staging/greybus/audio_manager.c | 184 ++++++++++++++ drivers/staging/greybus/audio_manager.h | 82 ++++++ .../staging/greybus/audio_manager_module.c | 240 ++++++++++++++++++ .../staging/greybus/audio_manager_private.h | 28 ++ drivers/staging/greybus/audio_manager_sysfs.c | 101 ++++++++ 6 files changed, 644 insertions(+) create mode 100644 drivers/staging/greybus/audio_manager.c create mode 100644 drivers/staging/greybus/audio_manager.h create mode 100644 drivers/staging/greybus/audio_manager_module.c create mode 100644 drivers/staging/greybus/audio_manager_private.h create mode 100644 drivers/staging/greybus/audio_manager_sysfs.c diff --git a/drivers/staging/greybus/Makefile b/drivers/staging/greybus/Makefile index e2ae24b32ab7..4ebdc6b9c89f 100644 --- a/drivers/staging/greybus/Makefile +++ b/drivers/staging/greybus/Makefile @@ -32,6 +32,8 @@ gb-arche-y := arche-platform.o arche-apb-ctrl.o gb-audio-codec-y := audio_codec.o gb-audio-gb-y := audio_gb.o gb-audio-apbridgea-y := audio_apbridgea.o +gb-audio-manager-y += audio_manager.o +gb-audio-manager-y += audio_manager_module.o gb-camera-y := camera.o obj-m += greybus.o @@ -48,6 +50,7 @@ obj-m += gb-audio-codec.o obj-m += gb-camera.o obj-m += gb-audio-gb.o obj-m += gb-audio-apbridgea.o +obj-m += gb-audio-manager.o KERNELVER ?= $(shell uname -r) KERNELDIR ?= /lib/modules/$(KERNELVER)/build @@ -89,6 +92,12 @@ ccflags-y := -Wall # needed for trace events ccflags-y += -I$(src) +GB_AUDIO_MANAGER_SYSFS ?= true +ifeq ($(GB_AUDIO_MANAGER_SYSFS),true) +gb-audio-manager-y += audio_manager_sysfs.o +ccflags-y += -DGB_AUDIO_MANAGER_SYSFS +endif + all: module tools:: diff --git a/drivers/staging/greybus/audio_manager.c b/drivers/staging/greybus/audio_manager.c new file mode 100644 index 000000000000..117676314daf --- /dev/null +++ b/drivers/staging/greybus/audio_manager.c @@ -0,0 +1,184 @@ +/* + * Greybus operations + * + * Copyright 2015-2016 Google Inc. + * + * Released under the GPLv2 only. + */ + +#include +#include +#include +#include +#include + +#include "audio_manager.h" +#include "audio_manager_private.h" + +static struct kset *manager_kset; + +static LIST_HEAD(modules_list); +static DEFINE_RWLOCK(modules_lock); + +static int current_module_id; + +/* helpers */ +static struct gb_audio_manager_module *gb_audio_manager_get_locked(int id) +{ + struct gb_audio_manager_module *module; + + if (id < 0) + return NULL; + + list_for_each_entry(module, &modules_list, list) { + if (module->id == id) + return module; + } + + return NULL; +} + +/* public API */ +int gb_audio_manager_add(struct gb_audio_manager_module_descriptor *desc) +{ + struct gb_audio_manager_module *module; + unsigned long flags; + int err; + + err = gb_audio_manager_module_create(&module, manager_kset, + current_module_id++, desc); + if (err) + return err; + + /* Add it to the list */ + write_lock_irqsave(&modules_lock, flags); + list_add_tail(&module->list, &modules_list); + write_unlock_irqrestore(&modules_lock, flags); + + return module->id; +} +EXPORT_SYMBOL_GPL(gb_audio_manager_add); + +int gb_audio_manager_remove(int id) +{ + struct gb_audio_manager_module *module; + unsigned long flags; + + write_lock_irqsave(&modules_lock, flags); + + module = gb_audio_manager_get_locked(id); + if (!module) { + write_unlock_irqrestore(&modules_lock, flags); + return -EINVAL; + } + + list_del(&module->list); + kobject_put(&module->kobj); + write_unlock_irqrestore(&modules_lock, flags); + return 0; +} +EXPORT_SYMBOL_GPL(gb_audio_manager_remove); + +void gb_audio_manager_remove_all(void) +{ + struct gb_audio_manager_module *module, *next; + int is_empty = 1; + unsigned long flags; + + write_lock_irqsave(&modules_lock, flags); + + list_for_each_entry_safe(module, next, &modules_list, list) { + list_del(&module->list); + kobject_put(&module->kobj); + } + + is_empty = list_empty(&modules_list); + + write_unlock_irqrestore(&modules_lock, flags); + + if (!is_empty) + pr_warn("Not all nodes were deleted\n"); +} +EXPORT_SYMBOL_GPL(gb_audio_manager_remove_all); + +struct gb_audio_manager_module *gb_audio_manager_get_module(int id) +{ + struct gb_audio_manager_module *module; + unsigned long flags; + + read_lock_irqsave(&modules_lock, flags); + module = gb_audio_manager_get_locked(id); + kobject_get(&module->kobj); + read_unlock_irqrestore(&modules_lock, flags); + return module; +} +EXPORT_SYMBOL_GPL(gb_audio_manager_get_module); + +void gb_audio_manager_put_module(struct gb_audio_manager_module *module) +{ + kobject_put(&module->kobj); +} +EXPORT_SYMBOL_GPL(gb_audio_manager_put_module); + +int gb_audio_manager_dump_module(int id) +{ + struct gb_audio_manager_module *module; + unsigned long flags; + + read_lock_irqsave(&modules_lock, flags); + module = gb_audio_manager_get_locked(id); + read_unlock_irqrestore(&modules_lock, flags); + + if (!module) + return -EINVAL; + + gb_audio_manager_module_dump(module); + return 0; +} +EXPORT_SYMBOL_GPL(gb_audio_manager_dump_module); + +void gb_audio_manager_dump_all(void) +{ + struct gb_audio_manager_module *module; + int count = 0; + unsigned long flags; + + read_lock_irqsave(&modules_lock, flags); + list_for_each_entry(module, &modules_list, list) { + gb_audio_manager_module_dump(module); + count++; + } + read_unlock_irqrestore(&modules_lock, flags); + + pr_info("Number of connected modules: %d\n", count); +} +EXPORT_SYMBOL_GPL(gb_audio_manager_dump_all); + +/* + * module init/deinit + */ +static int __init manager_init(void) +{ + manager_kset = kset_create_and_add(GB_AUDIO_MANAGER_NAME, NULL, + kernel_kobj); + if (!manager_kset) + return -ENOMEM; + +#ifdef GB_AUDIO_MANAGER_SYSFS + gb_audio_manager_sysfs_init(&manager_kset->kobj); +#endif + + return 0; +} + +static void __exit manager_exit(void) +{ + gb_audio_manager_remove_all(); + kset_unregister(manager_kset); +} + +module_init(manager_init); +module_exit(manager_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Svetlin Ankov "); diff --git a/drivers/staging/greybus/audio_manager.h b/drivers/staging/greybus/audio_manager.h new file mode 100644 index 000000000000..9ca7ac09719e --- /dev/null +++ b/drivers/staging/greybus/audio_manager.h @@ -0,0 +1,82 @@ +/* + * Greybus operations + * + * Copyright 2015-2016 Google Inc. + * + * Released under the GPLv2 only. + */ + +#ifndef _GB_AUDIO_MANAGER_H_ +#define _GB_AUDIO_MANAGER_H_ + +#include +#include + +#define GB_AUDIO_MANAGER_NAME "gb_audio_manager" +#define GB_AUDIO_MANAGER_MODULE_NAME_LEN 64 +#define GB_AUDIO_MANAGER_MODULE_NAME_LEN_SSCANF "63" + +struct gb_audio_manager_module_descriptor { + char name[GB_AUDIO_MANAGER_MODULE_NAME_LEN]; + int slot; + int vid; + int pid; + int cport; + unsigned int devices; +}; + +struct gb_audio_manager_module { + struct kobject kobj; + struct list_head list; + int id; + struct gb_audio_manager_module_descriptor desc; +}; + +/* + * Creates a new gb_audio_manager_module_descriptor, using the specified + * descriptor. + * + * Returns a negative result on error, or the id of the newly created module. + * + */ +int gb_audio_manager_add(struct gb_audio_manager_module_descriptor *desc); + +/* + * Removes a connected gb_audio_manager_module_descriptor for the specified ID. + * + * Returns zero on success, or a negative value on error. + */ +int gb_audio_manager_remove(int id); + +/* + * Removes all connected gb_audio_modules + * + * Returns zero on success, or a negative value on error. + */ +void gb_audio_manager_remove_all(void); + +/* + * Retrieves a gb_audio_manager_module_descriptor for the specified id. + * Returns the gb_audio_manager_module_descriptor structure, + * or NULL if there is no module with the specified ID. + */ +struct gb_audio_manager_module *gb_audio_manager_get_module(int id); + +/* + * Decreases the refcount of the module, obtained by the get function. + * Modules are removed via gb_audio_manager_remove + */ +void gb_audio_manager_put_module(struct gb_audio_manager_module *module); + +/* + * Dumps the module for the specified id + * Return 0 on success + */ +int gb_audio_manager_dump_module(int id); + +/* + * Dumps all connected modules + */ +void gb_audio_manager_dump_all(void); + +#endif /* _GB_AUDIO_MANAGER_H_ */ diff --git a/drivers/staging/greybus/audio_manager_module.c b/drivers/staging/greybus/audio_manager_module.c new file mode 100644 index 000000000000..e5cffa362671 --- /dev/null +++ b/drivers/staging/greybus/audio_manager_module.c @@ -0,0 +1,240 @@ +/* + * Greybus operations + * + * Copyright 2015-2016 Google Inc. + * + * Released under the GPLv2 only. + */ + +#include + +#include "audio_manager.h" +#include "audio_manager_private.h" + +#define to_gb_audio_module_attr(x) \ + container_of(x, struct gb_audio_manager_module_attribute, attr) +#define to_gb_audio_module(x) \ + container_of(x, struct gb_audio_manager_module, kobj) + +struct gb_audio_manager_module_attribute { + struct attribute attr; + ssize_t (*show)(struct gb_audio_manager_module *module, + struct gb_audio_manager_module_attribute *attr, + char *buf); + ssize_t (*store)(struct gb_audio_manager_module *module, + struct gb_audio_manager_module_attribute *attr, + const char *buf, size_t count); +}; + +static ssize_t gb_audio_module_attr_show( + struct kobject *kobj, struct attribute *attr, char *buf) +{ + struct gb_audio_manager_module_attribute *attribute; + struct gb_audio_manager_module *module; + + attribute = to_gb_audio_module_attr(attr); + module = to_gb_audio_module(kobj); + + if (!attribute->show) + return -EIO; + + return attribute->show(module, attribute, buf); +} + +static ssize_t gb_audio_module_attr_store(struct kobject *kobj, + struct attribute *attr, + const char *buf, size_t len) +{ + struct gb_audio_manager_module_attribute *attribute; + struct gb_audio_manager_module *module; + + attribute = to_gb_audio_module_attr(attr); + module = to_gb_audio_module(kobj); + + if (!attribute->store) + return -EIO; + + return attribute->store(module, attribute, buf, len); +} + +static const struct sysfs_ops gb_audio_module_sysfs_ops = { + .show = gb_audio_module_attr_show, + .store = gb_audio_module_attr_store, +}; + +static void gb_audio_module_release(struct kobject *kobj) +{ + struct gb_audio_manager_module *module = to_gb_audio_module(kobj); + + pr_info("Destroying audio module #%d\n", module->id); + /* TODO -> delete from list */ + kfree(module); +} + +static ssize_t gb_audio_module_name_show( + struct gb_audio_manager_module *module, + struct gb_audio_manager_module_attribute *attr, char *buf) +{ + return sprintf(buf, "%s", module->desc.name); +} + +static struct gb_audio_manager_module_attribute gb_audio_module_name_attribute = + __ATTR(name, 0664, gb_audio_module_name_show, NULL); + +static ssize_t gb_audio_module_slot_show( + struct gb_audio_manager_module *module, + struct gb_audio_manager_module_attribute *attr, char *buf) +{ + return sprintf(buf, "%d", module->desc.slot); +} + +static struct gb_audio_manager_module_attribute gb_audio_module_slot_attribute = + __ATTR(slot, 0664, gb_audio_module_slot_show, NULL); + +static ssize_t gb_audio_module_vid_show( + struct gb_audio_manager_module *module, + struct gb_audio_manager_module_attribute *attr, char *buf) +{ + return sprintf(buf, "%d", module->desc.vid); +} + +static struct gb_audio_manager_module_attribute gb_audio_module_vid_attribute = + __ATTR(vid, 0664, gb_audio_module_vid_show, NULL); + +static ssize_t gb_audio_module_pid_show( + struct gb_audio_manager_module *module, + struct gb_audio_manager_module_attribute *attr, char *buf) +{ + return sprintf(buf, "%d", module->desc.pid); +} + +static struct gb_audio_manager_module_attribute gb_audio_module_pid_attribute = + __ATTR(pid, 0664, gb_audio_module_pid_show, NULL); + +static ssize_t gb_audio_module_cport_show( + struct gb_audio_manager_module *module, + struct gb_audio_manager_module_attribute *attr, char *buf) +{ + return sprintf(buf, "%d", module->desc.cport); +} + +static struct gb_audio_manager_module_attribute + gb_audio_module_cport_attribute = + __ATTR(cport, 0664, gb_audio_module_cport_show, NULL); + +static ssize_t gb_audio_module_devices_show( + struct gb_audio_manager_module *module, + struct gb_audio_manager_module_attribute *attr, char *buf) +{ + return sprintf(buf, "0x%X", module->desc.devices); +} + +static struct gb_audio_manager_module_attribute + gb_audio_module_devices_attribute = + __ATTR(devices, 0664, gb_audio_module_devices_show, NULL); + +static struct attribute *gb_audio_module_default_attrs[] = { + &gb_audio_module_name_attribute.attr, + &gb_audio_module_slot_attribute.attr, + &gb_audio_module_vid_attribute.attr, + &gb_audio_module_pid_attribute.attr, + &gb_audio_module_cport_attribute.attr, + &gb_audio_module_devices_attribute.attr, + NULL, /* need to NULL terminate the list of attributes */ +}; + +static struct kobj_type gb_audio_module_type = { + .sysfs_ops = &gb_audio_module_sysfs_ops, + .release = gb_audio_module_release, + .default_attrs = gb_audio_module_default_attrs, +}; + +static void send_add_uevent(struct gb_audio_manager_module *module) +{ + char name_string[128]; + char slot_string[64]; + char vid_string[64]; + char pid_string[64]; + char cport_string[64]; + char devices_string[64]; + + char *envp[] = { + name_string, + slot_string, + vid_string, + pid_string, + cport_string, + devices_string, + NULL + }; + + snprintf(name_string, 128, "NAME=%s", module->desc.name); + snprintf(slot_string, 64, "SLOT=%d", module->desc.slot); + snprintf(vid_string, 64, "VID=%d", module->desc.vid); + snprintf(pid_string, 64, "PID=%d", module->desc.pid); + snprintf(cport_string, 64, "CPORT=%d", module->desc.cport); + snprintf(devices_string, 64, "DEVICES=0x%X", module->desc.devices); + + kobject_uevent_env(&module->kobj, KOBJ_ADD, envp); +} + +int gb_audio_manager_module_create( + struct gb_audio_manager_module **module, + struct kset *manager_kset, + int id, struct gb_audio_manager_module_descriptor *desc) +{ + int err; + struct gb_audio_manager_module *m; + + m = kzalloc(sizeof(*m), GFP_ATOMIC); + if (!m) + return -ENOMEM; + + /* Initialize the node */ + INIT_LIST_HEAD(&m->list); + + /* Set the module id */ + m->id = id; + + /* Copy the provided descriptor */ + memcpy(&m->desc, desc, sizeof(*desc)); + + /* set the kset */ + m->kobj.kset = manager_kset; + + /* + * Initialize and add the kobject to the kernel. All the default files + * will be created here. As we have already specified a kset for this + * kobject, we don't have to set a parent for the kobject, the kobject + * will be placed beneath that kset automatically. + */ + err = kobject_init_and_add(&m->kobj, &gb_audio_module_type, NULL, "%d", + id); + if (err) { + pr_err("failed initializing kobject for audio module #%d\n", + id); + kobject_put(&m->kobj); + return err; + } + + /* + * Notify the object was created + */ + send_add_uevent(m); + + *module = m; + pr_info("Created audio module #%d\n", id); + return 0; +} + +void gb_audio_manager_module_dump(struct gb_audio_manager_module *module) +{ + pr_info("audio module #%d name=%s slot=%d vid=%d pid=%d cport=%d devices=0x%X\n", + module->id, + module->desc.name, + module->desc.slot, + module->desc.vid, + module->desc.pid, + module->desc.cport, + module->desc.devices); +} diff --git a/drivers/staging/greybus/audio_manager_private.h b/drivers/staging/greybus/audio_manager_private.h new file mode 100644 index 000000000000..079ce953c256 --- /dev/null +++ b/drivers/staging/greybus/audio_manager_private.h @@ -0,0 +1,28 @@ +/* + * Greybus operations + * + * Copyright 2015-2016 Google Inc. + * + * Released under the GPLv2 only. + */ + +#ifndef _GB_AUDIO_MANAGER_PRIVATE_H_ +#define _GB_AUDIO_MANAGER_PRIVATE_H_ + +#include + +#include "audio_manager.h" + +int gb_audio_manager_module_create( + struct gb_audio_manager_module **module, + struct kset *manager_kset, + int id, struct gb_audio_manager_module_descriptor *desc); + +/* module destroyed via kobject_put */ + +void gb_audio_manager_module_dump(struct gb_audio_manager_module *module); + +/* sysfs control */ +void gb_audio_manager_sysfs_init(struct kobject *kobj); + +#endif /* _GB_AUDIO_MANAGER_PRIVATE_H_ */ diff --git a/drivers/staging/greybus/audio_manager_sysfs.c b/drivers/staging/greybus/audio_manager_sysfs.c new file mode 100644 index 000000000000..c713f5f7aaca --- /dev/null +++ b/drivers/staging/greybus/audio_manager_sysfs.c @@ -0,0 +1,101 @@ +/* + * Greybus operations + * + * Copyright 2015-2016 Google Inc. + * + * Released under the GPLv2 only. + */ + +#include +#include + +#include "audio_manager.h" +#include "audio_manager_private.h" + +static ssize_t manager_sysfs_add_store( + struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t count) +{ + struct gb_audio_manager_module_descriptor desc = { {0} }; + + int num = sscanf(buf, + "name=%" GB_AUDIO_MANAGER_MODULE_NAME_LEN_SSCANF "s " + "slot=%d vid=%d pid=%d cport=%d devices=0x%X", + desc.name, &desc.slot, &desc.vid, &desc.pid, + &desc.cport, &desc.devices); + + if (num != 6) + return -EINVAL; + + num = gb_audio_manager_add(&desc); + if (num < 0) + return -EINVAL; + + return count; +} + +static struct kobj_attribute manager_add_attribute = + __ATTR(add, 0664, NULL, manager_sysfs_add_store); + +static ssize_t manager_sysfs_remove_store( + struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t count) +{ + int id; + + int num = sscanf(buf, "%d", &id); + + if (num != 1) + return -EINVAL; + + num = gb_audio_manager_remove(id); + if (num) + return num; + + return count; +} + +static struct kobj_attribute manager_remove_attribute = + __ATTR(remove, 0664, NULL, manager_sysfs_remove_store); + +static ssize_t manager_sysfs_dump_store( + struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t count) +{ + int id; + + int num = sscanf(buf, "%d", &id); + + if (num == 1) { + num = gb_audio_manager_dump_module(id); + if (num) + return num; + } else if (!strncmp("all", buf, 3)) + gb_audio_manager_dump_all(); + else + return -EINVAL; + + return count; +} + +static struct kobj_attribute manager_dump_attribute = + __ATTR(dump, 0664, NULL, manager_sysfs_dump_store); + +static void manager_sysfs_init_attribute( + struct kobject *kobj, struct kobj_attribute *kattr) +{ + int err; + + err = sysfs_create_file(kobj, &kattr->attr); + if (err) { + pr_warn("creating the sysfs entry for %s failed: %d\n", + kattr->attr.name, err); + } +} + +void gb_audio_manager_sysfs_init(struct kobject *kobj) +{ + manager_sysfs_init_attribute(kobj, &manager_add_attribute); + manager_sysfs_init_attribute(kobj, &manager_remove_attribute); + manager_sysfs_init_attribute(kobj, &manager_dump_attribute); +}