From 111b0cdb97d44cfe5dec1338a78ba8aff65c32e2 Mon Sep 17 00:00:00 2001
From: Takashi Iwai <tiwai@suse.de>
Date: Fri, 9 Jun 2017 15:11:58 +0200
Subject: [PATCH] ALSA: seq: Allow the modular sequencer registration
Git-commit: 111b0cdb97d44cfe5dec1338a78ba8aff65c32e2
Patch-mainline: v4.13-rc1
References: bsc#1121278
Many drivers bind the sequencer stuff in off-load by another driver
module, so that it's loaded only on demand. In the current code, this
mechanism doesn't work when the driver is built-in while the sequencer
is module. We check with IS_REACHABLE() and enable only when the
sequencer is in the same level of build.
However, this is basically a overshoot. The binder code
(snd-seq-device) is an individual module from the sequencer core
(snd-seq), and we just have to make the former a built-in while
keeping the latter a module for allowing the scenario like the above.
This patch achieves that by rewriting Kconfig slightly. Now, a driver
that provides the manual sequencer device binding should select
CONFIG_SND_SEQ_DEVICE in a way as
select SND_SEQ_DEVICE if SND_SEQUENCER != n
Note that the "!=n" is needed here to avoid the influence of the
sequencer core is module while the driver is built-in.
Also, since rawmidi.o may be linked with snd_seq_device.o when
built-in, we have to shuffle the code to make the linker happy.
(the kernel linker isn't smart enough yet to handle such a case.)
That is, snd_seq_device.c is moved to sound/core from sound/core/seq,
as well as Makefile.
Last but not least, the patch replaces the code using IS_REACHABLE()
with IS_ENABLED(), since now the condition meets always when enabled.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
---
sound/core/Kconfig | 4 ++++
sound/core/Makefile | 2 ++
sound/core/rawmidi.c | 4 ++--
sound/core/seq/Kconfig | 2 +-
sound/core/seq/Makefile | 3 +--
sound/core/{seq => }/seq_device.c | 0
sound/core/Kconfig | 4
sound/core/Makefile | 2
sound/core/rawmidi.c | 4
sound/core/seq/Kconfig | 2
sound/core/seq/Makefile | 3
sound/core/seq/seq_device.c | 315 ----------------------------------------
sound/core/seq_device.c | 315 ++++++++++++++++++++++++++++++++++++++++
sound/drivers/Kconfig | 2
sound/drivers/opl3/opl3_lib.c | 2
sound/drivers/opl4/opl4_lib.c | 4
sound/drivers/opl4/opl4_local.h | 2
sound/isa/Kconfig | 1
sound/isa/sb/emu8000.c | 2
sound/isa/sb/sb16.c | 2
sound/pci/Kconfig | 1
sound/pci/emu10k1/emu10k1.c | 2
16 files changed, 336 insertions(+), 327 deletions(-)
rename sound/core/{seq => }/seq_device.c (100%)
--- a/sound/core/Kconfig
+++ b/sound/core/Kconfig
@@ -18,8 +18,12 @@ config SND_DMAENGINE_PCM
config SND_HWDEP
tristate
+config SND_SEQ_DEVICE
+ tristate
+
config SND_RAWMIDI
tristate
+ select SND_SEQ_DEVICE if SND_SEQUENCER != n
config SND_COMPRESS_OFFLOAD
tristate
--- a/sound/core/Makefile
+++ b/sound/core/Makefile
@@ -31,6 +31,7 @@ snd-timer-objs := timer.o
snd-hrtimer-objs := hrtimer.o
snd-rtctimer-objs := rtctimer.o
snd-hwdep-objs := hwdep.o
+snd-seq-device-objs := seq_device.o
snd-compress-objs := compress_offload.o
@@ -40,6 +41,7 @@ obj-$(CONFIG_SND_TIMER) += snd-timer.o
obj-$(CONFIG_SND_HRTIMER) += snd-hrtimer.o
obj-$(CONFIG_SND_PCM) += snd-pcm.o
obj-$(CONFIG_SND_DMAENGINE_PCM) += snd-pcm-dmaengine.o
+obj-$(CONFIG_SND_SEQ_DEVICE) += snd-seq-device.o
obj-$(CONFIG_SND_RAWMIDI) += snd-rawmidi.o
obj-$(CONFIG_SND_OSSEMUL) += oss/
--- a/sound/core/rawmidi.c
+++ b/sound/core/rawmidi.c
@@ -1610,7 +1610,7 @@ static int snd_rawmidi_dev_free(struct s
return snd_rawmidi_free(rmidi);
}
-#if IS_REACHABLE(CONFIG_SND_SEQUENCER)
+#if IS_ENABLED(CONFIG_SND_SEQUENCER)
static void snd_rawmidi_dev_seq_free(struct snd_seq_device *device)
{
struct snd_rawmidi *rmidi = device->private_data;
@@ -1691,7 +1691,7 @@ static int snd_rawmidi_dev_register(stru
}
}
rmidi->proc_entry = entry;
-#if IS_REACHABLE(CONFIG_SND_SEQUENCER)
+#if IS_ENABLED(CONFIG_SND_SEQUENCER)
if (!rmidi->ops || !rmidi->ops->dev_register) { /* own registration mechanism */
if (snd_seq_device_new(rmidi->card, rmidi->device, SNDRV_SEQ_DEV_ID_MIDISYNTH, 0, &rmidi->seq_dev) >= 0) {
rmidi->seq_dev->private_data = rmidi;
--- a/sound/core/seq/Kconfig
+++ b/sound/core/seq/Kconfig
@@ -1,6 +1,7 @@
config SND_SEQUENCER
tristate "Sequencer support"
select SND_TIMER
+ select SND_SEQ_DEVICE
help
Say Y or M to enable MIDI sequencer and router support. This
feature allows routing and enqueueing of MIDI events. Events
@@ -59,4 +60,3 @@ config SND_SEQ_VIRMIDI
tristate
endif # SND_SEQUENCER
-
--- a/sound/core/seq/Makefile
+++ b/sound/core/seq/Makefile
@@ -3,7 +3,6 @@
# Copyright (c) 1999 by Jaroslav Kysela <perex@perex.cz>
#
-snd-seq-device-objs := seq_device.o
snd-seq-objs := seq.o seq_lock.o seq_clientmgr.o seq_memory.o seq_queue.o \
seq_fifo.o seq_prioq.o seq_timer.o \
seq_system.o seq_ports.o
@@ -14,7 +13,7 @@ snd-seq-midi-event-objs := seq_midi_even
snd-seq-dummy-objs := seq_dummy.o
snd-seq-virmidi-objs := seq_virmidi.o
-obj-$(CONFIG_SND_SEQUENCER) += snd-seq.o snd-seq-device.o
+obj-$(CONFIG_SND_SEQUENCER) += snd-seq.o
obj-$(CONFIG_SND_SEQUENCER_OSS) += oss/
obj-$(CONFIG_SND_SEQ_DUMMY) += snd-seq-dummy.o
--- a/sound/drivers/Kconfig
+++ b/sound/drivers/Kconfig
@@ -6,11 +6,13 @@ config SND_OPL3_LIB
tristate
select SND_TIMER
select SND_HWDEP
+ select SND_SEQ_DEVICE if SND_SEQUENCER != n
config SND_OPL4_LIB
tristate
select SND_TIMER
select SND_HWDEP
+ select SND_SEQ_DEVICE if SND_SEQUENCER != n
# select SEQ stuff to min(SND_SEQUENCER,SND_XXX)
config SND_OPL3_LIB_SEQ
--- a/sound/drivers/opl3/opl3_lib.c
+++ b/sound/drivers/opl3/opl3_lib.c
@@ -528,7 +528,7 @@ int snd_opl3_hwdep_new(struct snd_opl3 *
opl3->hwdep = hw;
opl3->seq_dev_num = seq_device;
-#if IS_REACHABLE(CONFIG_SND_SEQUENCER)
+#if IS_ENABLED(CONFIG_SND_SEQUENCER)
if (snd_seq_device_new(card, seq_device, SNDRV_SEQ_DEV_ID_OPL3,
sizeof(struct snd_opl3 *), &opl3->seq_dev) >= 0) {
strcpy(opl3->seq_dev->name, hw->name);
--- a/sound/drivers/opl4/opl4_lib.c
+++ b/sound/drivers/opl4/opl4_lib.c
@@ -153,7 +153,7 @@ static int snd_opl4_detect(struct snd_op
return 0;
}
-#if IS_REACHABLE(CONFIG_SND_SEQUENCER)
+#if IS_ENABLED(CONFIG_SND_SEQUENCER)
static void snd_opl4_seq_dev_free(struct snd_seq_device *seq_dev)
{
struct snd_opl4 *opl4 = seq_dev->private_data;
@@ -249,7 +249,7 @@ int snd_opl4_create(struct snd_card *car
snd_opl4_create_mixer(opl4);
snd_opl4_create_proc(opl4);
-#if IS_REACHABLE(CONFIG_SND_SEQUENCER)
+#if IS_ENABLED(CONFIG_SND_SEQUENCER)
opl4->seq_client = -1;
if (opl4->hardware < OPL3_HW_OPL4_ML)
snd_opl4_create_seq_dev(opl4, seq_device);
--- a/sound/drivers/opl4/opl4_local.h
+++ b/sound/drivers/opl4/opl4_local.h
@@ -184,7 +184,7 @@ struct snd_opl4 {
#endif
struct mutex access_mutex;
-#if IS_REACHABLE(CONFIG_SND_SEQUENCER)
+#if IS_ENABLED(CONFIG_SND_SEQUENCER)
int used;
int seq_dev_num;
--- a/sound/isa/Kconfig
+++ b/sound/isa/Kconfig
@@ -377,6 +377,7 @@ config SND_SBAWE
select SND_OPL3_LIB
select SND_MPU401_UART
select SND_SB16_DSP
+ select SND_SEQ_DEVICE if SND_SEQUENCER != n
help
Say Y here to include support for Sound Blaster AWE soundcards
(including the Plug and Play version).
--- a/sound/isa/sb/emu8000.c
+++ b/sound/isa/sb/emu8000.c
@@ -1138,7 +1138,7 @@ snd_emu8000_new(struct snd_card *card, i
snd_emu8000_free(hw);
return err;
}
-#if IS_REACHABLE(CONFIG_SND_SEQUENCER)
+#if IS_ENABLED(CONFIG_SND_SEQUENCER)
if (snd_seq_device_new(card, index, SNDRV_SEQ_DEV_ID_EMU8000,
sizeof(struct snd_emu8000*), &awe) >= 0) {
strcpy(awe->name, "EMU-8000");
--- a/sound/isa/sb/sb16.c
+++ b/sound/isa/sb/sb16.c
@@ -62,7 +62,7 @@ MODULE_SUPPORTED_DEVICE("{{Creative Labs
#define SNDRV_DEBUG_IRQ
#endif
-#if defined(SNDRV_SBAWE) && IS_REACHABLE(CONFIG_SND_SEQUENCER)
+#if defined(SNDRV_SBAWE) && IS_ENABLED(CONFIG_SND_SEQUENCER)
#define SNDRV_SBAWE_EMU8000
#endif
--- a/sound/pci/Kconfig
+++ b/sound/pci/Kconfig
@@ -465,6 +465,7 @@ config SND_EMU10K1
select SND_RAWMIDI
select SND_AC97_CODEC
select SND_TIMER
+ select SND_SEQ_DEVICE if SND_SEQUENCER != n
depends on ZONE_DMA
help
Say Y to include support for Sound Blaster PCI 512, Live!,
--- a/sound/pci/emu10k1/emu10k1.c
+++ b/sound/pci/emu10k1/emu10k1.c
@@ -37,7 +37,7 @@ MODULE_LICENSE("GPL");
MODULE_SUPPORTED_DEVICE("{{Creative Labs,SB Live!/PCI512/E-mu APS},"
"{Creative Labs,SB Audigy}}");
-#if IS_REACHABLE(CONFIG_SND_SEQUENCER)
+#if IS_ENABLED(CONFIG_SND_SEQUENCER)
#define ENABLE_SYNTH
#include <sound/emu10k1_synth.h>
#endif
--- a/sound/core/seq/seq_device.c
+++ /dev/null
@@ -1,315 +0,0 @@
-/*
- * ALSA sequencer device management
- * Copyright (c) 1999 by Takashi Iwai <tiwai@suse.de>
- *
- * 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
- *
- *
- *----------------------------------------------------------------
- *
- * This device handler separates the card driver module from sequencer
- * stuff (sequencer core, synth drivers, etc), so that user can avoid
- * to spend unnecessary resources e.g. if he needs only listening to
- * MP3s.
- *
- * The card (or lowlevel) driver creates a sequencer device entry
- * via snd_seq_device_new(). This is an entry pointer to communicate
- * with the sequencer device "driver", which is involved with the
- * actual part to communicate with the sequencer core.
- * Each sequencer device entry has an id string and the corresponding
- * driver with the same id is loaded when required. For example,
- * lowlevel codes to access emu8000 chip on sbawe card are included in
- * emu8000-synth module. To activate this module, the hardware
- * resources like i/o port are passed via snd_seq_device argument.
- *
- */
-
-#include <linux/device.h>
-#include <linux/init.h>
-#include <linux/module.h>
-#include <sound/core.h>
-#include <sound/info.h>
-#include <sound/seq_device.h>
-#include <sound/seq_kernel.h>
-#include <sound/initval.h>
-#include <linux/kmod.h>
-#include <linux/slab.h>
-#include <linux/mutex.h>
-
-MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>");
-MODULE_DESCRIPTION("ALSA sequencer device management");
-MODULE_LICENSE("GPL");
-
-/*
- * bus definition
- */
-static int snd_seq_bus_match(struct device *dev, struct device_driver *drv)
-{
- struct snd_seq_device *sdev = to_seq_dev(dev);
- struct snd_seq_driver *sdrv = to_seq_drv(drv);
-
- return strcmp(sdrv->id, sdev->id) == 0 &&
- sdrv->argsize == sdev->argsize;
-}
-
-static struct bus_type snd_seq_bus_type = {
- .name = "snd_seq",
- .match = snd_seq_bus_match,
-};
-
-/*
- * proc interface -- just for compatibility
- */
-#ifdef CONFIG_SND_PROC_FS
-static struct snd_info_entry *info_entry;
-
-static int print_dev_info(struct device *dev, void *data)
-{
- struct snd_seq_device *sdev = to_seq_dev(dev);
- struct snd_info_buffer *buffer = data;
-
- snd_iprintf(buffer, "snd-%s,%s,%d\n", sdev->id,
- dev->driver ? "loaded" : "empty",
- dev->driver ? 1 : 0);
- return 0;
-}
-
-static void snd_seq_device_info(struct snd_info_entry *entry,
- struct snd_info_buffer *buffer)
-{
- bus_for_each_dev(&snd_seq_bus_type, NULL, buffer, print_dev_info);
-}
-#endif
-
-/*
- * load all registered drivers (called from seq_clientmgr.c)
- */
-
-#ifdef CONFIG_MODULES
-/* flag to block auto-loading */
-static atomic_t snd_seq_in_init = ATOMIC_INIT(1); /* blocked as default */
-
-static int request_seq_drv(struct device *dev, void *data)
-{
- struct snd_seq_device *sdev = to_seq_dev(dev);
-
- if (!dev->driver)
- request_module("snd-%s", sdev->id);
- return 0;
-}
-
-static void autoload_drivers(struct work_struct *work)
-{
- /* avoid reentrance */
- if (atomic_inc_return(&snd_seq_in_init) == 1)
- bus_for_each_dev(&snd_seq_bus_type, NULL, NULL,
- request_seq_drv);
- atomic_dec(&snd_seq_in_init);
-}
-
-static DECLARE_WORK(autoload_work, autoload_drivers);
-
-static void queue_autoload_drivers(void)
-{
- schedule_work(&autoload_work);
-}
-
-void snd_seq_autoload_init(void)
-{
- atomic_dec(&snd_seq_in_init);
-#ifdef CONFIG_SND_SEQUENCER_MODULE
- /* initial autoload only when snd-seq is a module */
- queue_autoload_drivers();
-#endif
-}
-EXPORT_SYMBOL(snd_seq_autoload_init);
-
-void snd_seq_autoload_exit(void)
-{
- atomic_inc(&snd_seq_in_init);
-}
-EXPORT_SYMBOL(snd_seq_autoload_exit);
-
-void snd_seq_device_load_drivers(void)
-{
- queue_autoload_drivers();
- flush_work(&autoload_work);
-}
-EXPORT_SYMBOL(snd_seq_device_load_drivers);
-#else
-#define queue_autoload_drivers() /* NOP */
-#endif
-
-/*
- * device management
- */
-static int snd_seq_device_dev_free(struct snd_device *device)
-{
- struct snd_seq_device *dev = device->device_data;
-
- put_device(&dev->dev);
- return 0;
-}
-
-static int snd_seq_device_dev_register(struct snd_device *device)
-{
- struct snd_seq_device *dev = device->device_data;
- int err;
-
- err = device_add(&dev->dev);
- if (err < 0)
- return err;
- if (!dev->dev.driver)
- queue_autoload_drivers();
- return 0;
-}
-
-static int snd_seq_device_dev_disconnect(struct snd_device *device)
-{
- struct snd_seq_device *dev = device->device_data;
-
- device_del(&dev->dev);
- return 0;
-}
-
-static void snd_seq_dev_release(struct device *dev)
-{
- struct snd_seq_device *sdev = to_seq_dev(dev);
-
- if (sdev->private_free)
- sdev->private_free(sdev);
- kfree(sdev);
-}
-
-/*
- * register a sequencer device
- * card = card info
- * device = device number (if any)
- * id = id of driver
- * result = return pointer (NULL allowed if unnecessary)
- */
-int snd_seq_device_new(struct snd_card *card, int device, const char *id,
- int argsize, struct snd_seq_device **result)
-{
- struct snd_seq_device *dev;
- int err;
- static struct snd_device_ops dops = {
- .dev_free = snd_seq_device_dev_free,
- .dev_register = snd_seq_device_dev_register,
- .dev_disconnect = snd_seq_device_dev_disconnect,
- };
-
- if (result)
- *result = NULL;
-
- if (snd_BUG_ON(!id))
- return -EINVAL;
-
- dev = kzalloc(sizeof(*dev) + argsize, GFP_KERNEL);
- if (!dev)
- return -ENOMEM;
-
- /* set up device info */
- dev->card = card;
- dev->device = device;
- dev->id = id;
- dev->argsize = argsize;
-
- device_initialize(&dev->dev);
- dev->dev.parent = &card->card_dev;
- dev->dev.bus = &snd_seq_bus_type;
- dev->dev.release = snd_seq_dev_release;
- dev_set_name(&dev->dev, "%s-%d-%d", dev->id, card->number, device);
-
- /* add this device to the list */
- err = snd_device_new(card, SNDRV_DEV_SEQUENCER, dev, &dops);
- if (err < 0) {
- put_device(&dev->dev);
- return err;
- }
-
- if (result)
- *result = dev;
-
- return 0;
-}
-EXPORT_SYMBOL(snd_seq_device_new);
-
-/*
- * driver registration
- */
-int __snd_seq_driver_register(struct snd_seq_driver *drv, struct module *mod)
-{
- if (WARN_ON(!drv->driver.name || !drv->id))
- return -EINVAL;
- drv->driver.bus = &snd_seq_bus_type;
- drv->driver.owner = mod;
- return driver_register(&drv->driver);
-}
-EXPORT_SYMBOL_GPL(__snd_seq_driver_register);
-
-void snd_seq_driver_unregister(struct snd_seq_driver *drv)
-{
- driver_unregister(&drv->driver);
-}
-EXPORT_SYMBOL_GPL(snd_seq_driver_unregister);
-
-/*
- * module part
- */
-
-static int __init seq_dev_proc_init(void)
-{
-#ifdef CONFIG_SND_PROC_FS
- info_entry = snd_info_create_module_entry(THIS_MODULE, "drivers",
- snd_seq_root);
- if (info_entry == NULL)
- return -ENOMEM;
- info_entry->content = SNDRV_INFO_CONTENT_TEXT;
- info_entry->c.text.read = snd_seq_device_info;
- if (snd_info_register(info_entry) < 0) {
- snd_info_free_entry(info_entry);
- return -ENOMEM;
- }
-#endif
- return 0;
-}
-
-static int __init alsa_seq_device_init(void)
-{
- int err;
-
- err = bus_register(&snd_seq_bus_type);
- if (err < 0)
- return err;
- err = seq_dev_proc_init();
- if (err < 0)
- bus_unregister(&snd_seq_bus_type);
- return err;
-}
-
-static void __exit alsa_seq_device_exit(void)
-{
-#ifdef CONFIG_MODULES
- cancel_work_sync(&autoload_work);
-#endif
-#ifdef CONFIG_SND_PROC_FS
- snd_info_free_entry(info_entry);
-#endif
- bus_unregister(&snd_seq_bus_type);
-}
-
-subsys_initcall(alsa_seq_device_init)
-module_exit(alsa_seq_device_exit)
--- /dev/null
+++ b/sound/core/seq_device.c
@@ -0,0 +1,315 @@
+/*
+ * ALSA sequencer device management
+ * Copyright (c) 1999 by Takashi Iwai <tiwai@suse.de>
+ *
+ * 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
+ *
+ *
+ *----------------------------------------------------------------
+ *
+ * This device handler separates the card driver module from sequencer
+ * stuff (sequencer core, synth drivers, etc), so that user can avoid
+ * to spend unnecessary resources e.g. if he needs only listening to
+ * MP3s.
+ *
+ * The card (or lowlevel) driver creates a sequencer device entry
+ * via snd_seq_device_new(). This is an entry pointer to communicate
+ * with the sequencer device "driver", which is involved with the
+ * actual part to communicate with the sequencer core.
+ * Each sequencer device entry has an id string and the corresponding
+ * driver with the same id is loaded when required. For example,
+ * lowlevel codes to access emu8000 chip on sbawe card are included in
+ * emu8000-synth module. To activate this module, the hardware
+ * resources like i/o port are passed via snd_seq_device argument.
+ *
+ */
+
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <sound/core.h>
+#include <sound/info.h>
+#include <sound/seq_device.h>
+#include <sound/seq_kernel.h>
+#include <sound/initval.h>
+#include <linux/kmod.h>
+#include <linux/slab.h>
+#include <linux/mutex.h>
+
+MODULE_AUTHOR("Takashi Iwai <tiwai@suse.de>");
+MODULE_DESCRIPTION("ALSA sequencer device management");
+MODULE_LICENSE("GPL");
+
+/*
+ * bus definition
+ */
+static int snd_seq_bus_match(struct device *dev, struct device_driver *drv)
+{
+ struct snd_seq_device *sdev = to_seq_dev(dev);
+ struct snd_seq_driver *sdrv = to_seq_drv(drv);
+
+ return strcmp(sdrv->id, sdev->id) == 0 &&
+ sdrv->argsize == sdev->argsize;
+}
+
+static struct bus_type snd_seq_bus_type = {
+ .name = "snd_seq",
+ .match = snd_seq_bus_match,
+};
+
+/*
+ * proc interface -- just for compatibility
+ */
+#ifdef CONFIG_SND_PROC_FS
+static struct snd_info_entry *info_entry;
+
+static int print_dev_info(struct device *dev, void *data)
+{
+ struct snd_seq_device *sdev = to_seq_dev(dev);
+ struct snd_info_buffer *buffer = data;
+
+ snd_iprintf(buffer, "snd-%s,%s,%d\n", sdev->id,
+ dev->driver ? "loaded" : "empty",
+ dev->driver ? 1 : 0);
+ return 0;
+}
+
+static void snd_seq_device_info(struct snd_info_entry *entry,
+ struct snd_info_buffer *buffer)
+{
+ bus_for_each_dev(&snd_seq_bus_type, NULL, buffer, print_dev_info);
+}
+#endif
+
+/*
+ * load all registered drivers (called from seq_clientmgr.c)
+ */
+
+#ifdef CONFIG_MODULES
+/* flag to block auto-loading */
+static atomic_t snd_seq_in_init = ATOMIC_INIT(1); /* blocked as default */
+
+static int request_seq_drv(struct device *dev, void *data)
+{
+ struct snd_seq_device *sdev = to_seq_dev(dev);
+
+ if (!dev->driver)
+ request_module("snd-%s", sdev->id);
+ return 0;
+}
+
+static void autoload_drivers(struct work_struct *work)
+{
+ /* avoid reentrance */
+ if (atomic_inc_return(&snd_seq_in_init) == 1)
+ bus_for_each_dev(&snd_seq_bus_type, NULL, NULL,
+ request_seq_drv);
+ atomic_dec(&snd_seq_in_init);
+}
+
+static DECLARE_WORK(autoload_work, autoload_drivers);
+
+static void queue_autoload_drivers(void)
+{
+ schedule_work(&autoload_work);
+}
+
+void snd_seq_autoload_init(void)
+{
+ atomic_dec(&snd_seq_in_init);
+#ifdef CONFIG_SND_SEQUENCER_MODULE
+ /* initial autoload only when snd-seq is a module */
+ queue_autoload_drivers();
+#endif
+}
+EXPORT_SYMBOL(snd_seq_autoload_init);
+
+void snd_seq_autoload_exit(void)
+{
+ atomic_inc(&snd_seq_in_init);
+}
+EXPORT_SYMBOL(snd_seq_autoload_exit);
+
+void snd_seq_device_load_drivers(void)
+{
+ queue_autoload_drivers();
+ flush_work(&autoload_work);
+}
+EXPORT_SYMBOL(snd_seq_device_load_drivers);
+#else
+#define queue_autoload_drivers() /* NOP */
+#endif
+
+/*
+ * device management
+ */
+static int snd_seq_device_dev_free(struct snd_device *device)
+{
+ struct snd_seq_device *dev = device->device_data;
+
+ put_device(&dev->dev);
+ return 0;
+}
+
+static int snd_seq_device_dev_register(struct snd_device *device)
+{
+ struct snd_seq_device *dev = device->device_data;
+ int err;
+
+ err = device_add(&dev->dev);
+ if (err < 0)
+ return err;
+ if (!dev->dev.driver)
+ queue_autoload_drivers();
+ return 0;
+}
+
+static int snd_seq_device_dev_disconnect(struct snd_device *device)
+{
+ struct snd_seq_device *dev = device->device_data;
+
+ device_del(&dev->dev);
+ return 0;
+}
+
+static void snd_seq_dev_release(struct device *dev)
+{
+ struct snd_seq_device *sdev = to_seq_dev(dev);
+
+ if (sdev->private_free)
+ sdev->private_free(sdev);
+ kfree(sdev);
+}
+
+/*
+ * register a sequencer device
+ * card = card info
+ * device = device number (if any)
+ * id = id of driver
+ * result = return pointer (NULL allowed if unnecessary)
+ */
+int snd_seq_device_new(struct snd_card *card, int device, const char *id,
+ int argsize, struct snd_seq_device **result)
+{
+ struct snd_seq_device *dev;
+ int err;
+ static struct snd_device_ops dops = {
+ .dev_free = snd_seq_device_dev_free,
+ .dev_register = snd_seq_device_dev_register,
+ .dev_disconnect = snd_seq_device_dev_disconnect,
+ };
+
+ if (result)
+ *result = NULL;
+
+ if (snd_BUG_ON(!id))
+ return -EINVAL;
+
+ dev = kzalloc(sizeof(*dev) + argsize, GFP_KERNEL);
+ if (!dev)
+ return -ENOMEM;
+
+ /* set up device info */
+ dev->card = card;
+ dev->device = device;
+ dev->id = id;
+ dev->argsize = argsize;
+
+ device_initialize(&dev->dev);
+ dev->dev.parent = &card->card_dev;
+ dev->dev.bus = &snd_seq_bus_type;
+ dev->dev.release = snd_seq_dev_release;
+ dev_set_name(&dev->dev, "%s-%d-%d", dev->id, card->number, device);
+
+ /* add this device to the list */
+ err = snd_device_new(card, SNDRV_DEV_SEQUENCER, dev, &dops);
+ if (err < 0) {
+ put_device(&dev->dev);
+ return err;
+ }
+
+ if (result)
+ *result = dev;
+
+ return 0;
+}
+EXPORT_SYMBOL(snd_seq_device_new);
+
+/*
+ * driver registration
+ */
+int __snd_seq_driver_register(struct snd_seq_driver *drv, struct module *mod)
+{
+ if (WARN_ON(!drv->driver.name || !drv->id))
+ return -EINVAL;
+ drv->driver.bus = &snd_seq_bus_type;
+ drv->driver.owner = mod;
+ return driver_register(&drv->driver);
+}
+EXPORT_SYMBOL_GPL(__snd_seq_driver_register);
+
+void snd_seq_driver_unregister(struct snd_seq_driver *drv)
+{
+ driver_unregister(&drv->driver);
+}
+EXPORT_SYMBOL_GPL(snd_seq_driver_unregister);
+
+/*
+ * module part
+ */
+
+static int __init seq_dev_proc_init(void)
+{
+#ifdef CONFIG_SND_PROC_FS
+ info_entry = snd_info_create_module_entry(THIS_MODULE, "drivers",
+ snd_seq_root);
+ if (info_entry == NULL)
+ return -ENOMEM;
+ info_entry->content = SNDRV_INFO_CONTENT_TEXT;
+ info_entry->c.text.read = snd_seq_device_info;
+ if (snd_info_register(info_entry) < 0) {
+ snd_info_free_entry(info_entry);
+ return -ENOMEM;
+ }
+#endif
+ return 0;
+}
+
+static int __init alsa_seq_device_init(void)
+{
+ int err;
+
+ err = bus_register(&snd_seq_bus_type);
+ if (err < 0)
+ return err;
+ err = seq_dev_proc_init();
+ if (err < 0)
+ bus_unregister(&snd_seq_bus_type);
+ return err;
+}
+
+static void __exit alsa_seq_device_exit(void)
+{
+#ifdef CONFIG_MODULES
+ cancel_work_sync(&autoload_work);
+#endif
+#ifdef CONFIG_SND_PROC_FS
+ snd_info_free_entry(info_entry);
+#endif
+ bus_unregister(&snd_seq_bus_type);
+}
+
+subsys_initcall(alsa_seq_device_init)
+module_exit(alsa_seq_device_exit)