blob: 612a17e375d026b0215572f6d9dec83e04ad0c37 [file] [log] [blame]
/* SPDX-License-Identifier: GPL-2.0 */
/*
* HD-audio core stuff
*/
#ifndef __SOUND_HDAUDIO_H
#define __SOUND_HDAUDIO_H
#include <linux/device.h>
#include <linux/interrupt.h>
#include <linux/pm_runtime.h>
#include <linux/timecounter.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/memalloc.h>
#include <sound/hda_verbs.h>
#include <drm/i915_component.h>
/* codec node id */
typedef u16 hda_nid_t;
struct hdac_bus;
struct hdac_stream;
struct hdac_device;
struct hdac_driver;
struct hdac_widget_tree;
struct hda_device_id;
/*
* exported bus type
*/
extern struct bus_type snd_hda_bus_type;
/*
* generic arrays
*/
struct snd_array {
unsigned int used;
unsigned int alloced;
unsigned int elem_size;
unsigned int alloc_align;
void *list;
};
/*
* HD-audio codec base device
*/
struct hdac_device {
struct device dev;
int type;
struct hdac_bus *bus;
unsigned int addr; /* codec address */
struct list_head list; /* list point for bus codec_list */
hda_nid_t afg; /* AFG node id */
hda_nid_t mfg; /* MFG node id */
/* ids */
unsigned int vendor_id;
unsigned int subsystem_id;
unsigned int revision_id;
unsigned int afg_function_id;
unsigned int mfg_function_id;
unsigned int afg_unsol:1;
unsigned int mfg_unsol:1;
unsigned int power_caps; /* FG power caps */
const char *vendor_name; /* codec vendor name */
const char *chip_name; /* codec chip name */
/* verb exec op override */
int (*exec_verb)(struct hdac_device *dev, unsigned int cmd,
unsigned int flags, unsigned int *res);
/* widgets */
unsigned int num_nodes;
hda_nid_t start_nid, end_nid;
/* misc flags */
atomic_t in_pm; /* suspend/resume being performed */
/* sysfs */
struct mutex widget_lock;
struct hdac_widget_tree *widgets;
/* regmap */
struct regmap *regmap;
struct snd_array vendor_verbs;
bool lazy_cache:1; /* don't wake up for writes */
bool caps_overwriting:1; /* caps overwrite being in process */
bool cache_coef:1; /* cache COEF read/write too */
};
/* device/driver type used for matching */
enum {
HDA_DEV_CORE,
HDA_DEV_LEGACY,
HDA_DEV_ASOC,
};
enum {
SND_SKL_PCI_BIND_AUTO, /* automatic selection based on pci class */
SND_SKL_PCI_BIND_LEGACY,/* bind only with legacy driver */
SND_SKL_PCI_BIND_ASOC /* bind only with ASoC driver */
};
/* direction */
enum {
HDA_INPUT, HDA_OUTPUT
};
#define dev_to_hdac_dev(_dev) container_of(_dev, struct hdac_device, dev)
int snd_hdac_device_init(struct hdac_device *dev, struct hdac_bus *bus,
const char *name, unsigned int addr);
void snd_hdac_device_exit(struct hdac_device *dev);
int snd_hdac_device_register(struct hdac_device *codec);
void snd_hdac_device_unregister(struct hdac_device *codec);
int snd_hdac_device_set_chip_name(struct hdac_device *codec, const char *name);
int snd_hdac_codec_modalias(struct hdac_device *hdac, char *buf, size_t size);
int snd_hdac_refresh_widgets(struct hdac_device *codec);
unsigned int snd_hdac_make_cmd(struct hdac_device *codec, hda_nid_t nid,
unsigned int verb, unsigned int parm);
int snd_hdac_exec_verb(struct hdac_device *codec, unsigned int cmd,
unsigned int flags, unsigned int *res);
int snd_hdac_read(struct hdac_device *codec, hda_nid_t nid,
unsigned int verb, unsigned int parm, unsigned int *res);
int _snd_hdac_read_parm(struct hdac_device *codec, hda_nid_t nid, int parm,
unsigned int *res);
int snd_hdac_read_parm_uncached(struct hdac_device *codec, hda_nid_t nid,
int parm);
int snd_hdac_override_parm(struct hdac_device *codec, hda_nid_t nid,
unsigned int parm, unsigned int val);
int snd_hdac_get_connections(struct hdac_device *codec, hda_nid_t nid,
hda_nid_t *conn_list, int max_conns);
int snd_hdac_get_sub_nodes(struct hdac_device *codec, hda_nid_t nid,
hda_nid_t *start_id);
unsigned int snd_hdac_calc_stream_format(unsigned int rate,
unsigned int channels,
snd_pcm_format_t format,
unsigned int maxbps,
unsigned short spdif_ctls);
int snd_hdac_query_supported_pcm(struct hdac_device *codec, hda_nid_t nid,
u32 *ratesp, u64 *formatsp, unsigned int *bpsp);
bool snd_hdac_is_supported_format(struct hdac_device *codec, hda_nid_t nid,
unsigned int format);
int snd_hdac_codec_read(struct hdac_device *hdac, hda_nid_t nid,
int flags, unsigned int verb, unsigned int parm);
int snd_hdac_codec_write(struct hdac_device *hdac, hda_nid_t nid,
int flags, unsigned int verb, unsigned int parm);
bool snd_hdac_check_power_state(struct hdac_device *hdac,
hda_nid_t nid, unsigned int target_state);
unsigned int snd_hdac_sync_power_state(struct hdac_device *hdac,
hda_nid_t nid, unsigned int target_state);
/**
* snd_hdac_read_parm - read a codec parameter
* @codec: the codec object
* @nid: NID to read a parameter
* @parm: parameter to read
*
* Returns -1 for error. If you need to distinguish the error more
* strictly, use _snd_hdac_read_parm() directly.
*/
static inline int snd_hdac_read_parm(struct hdac_device *codec, hda_nid_t nid,
int parm)
{
unsigned int val;
return _snd_hdac_read_parm(codec, nid, parm, &val) < 0 ? -1 : val;
}
#ifdef CONFIG_PM
int snd_hdac_power_up(struct hdac_device *codec);
int snd_hdac_power_down(struct hdac_device *codec);
int snd_hdac_power_up_pm(struct hdac_device *codec);
int snd_hdac_power_down_pm(struct hdac_device *codec);
int snd_hdac_keep_power_up(struct hdac_device *codec);
/* call this at entering into suspend/resume callbacks in codec driver */
static inline void snd_hdac_enter_pm(struct hdac_device *codec)
{
atomic_inc(&codec->in_pm);
}
/* call this at leaving from suspend/resume callbacks in codec driver */
static inline void snd_hdac_leave_pm(struct hdac_device *codec)
{
atomic_dec(&codec->in_pm);
}
static inline bool snd_hdac_is_in_pm(struct hdac_device *codec)
{
return atomic_read(&codec->in_pm);
}
static inline bool snd_hdac_is_power_on(struct hdac_device *codec)
{
return !pm_runtime_suspended(&codec->dev);
}
#else
static inline int snd_hdac_power_up(struct hdac_device *codec) { return 0; }
static inline int snd_hdac_power_down(struct hdac_device *codec) { return 0; }
static inline int snd_hdac_power_up_pm(struct hdac_device *codec) { return 0; }
static inline int snd_hdac_power_down_pm(struct hdac_device *codec) { return 0; }
static inline int snd_hdac_keep_power_up(struct hdac_device *codec) { return 0; }
static inline void snd_hdac_enter_pm(struct hdac_device *codec) {}
static inline void snd_hdac_leave_pm(struct hdac_device *codec) {}
static inline bool snd_hdac_is_in_pm(struct hdac_device *codec) { return 0; }
static inline bool snd_hdac_is_power_on(struct hdac_device *codec) { return 1; }
#endif
/*
* HD-audio codec base driver
*/
struct hdac_driver {
struct device_driver driver;
int type;
const struct hda_device_id *id_table;
int (*match)(struct hdac_device *dev, struct hdac_driver *drv);
void (*unsol_event)(struct hdac_device *dev, unsigned int event);
/* fields used by ext bus APIs */
int (*probe)(struct hdac_device *dev);
int (*remove)(struct hdac_device *dev);
void (*shutdown)(struct hdac_device *dev);
};
#define drv_to_hdac_driver(_drv) container_of(_drv, struct hdac_driver, driver)
const struct hda_device_id *
hdac_get_device_id(struct hdac_device *hdev, struct hdac_driver *drv);
/*
* Bus verb operators
*/
struct hdac_bus_ops {
/* send a single command */
int (*command)(struct hdac_bus *bus, unsigned int cmd);
/* get a response from the last command */
int (*get_response)(struct hdac_bus *bus, unsigned int addr,
unsigned int *res);
};
/*
* ops used for ASoC HDA codec drivers
*/
struct hdac_ext_bus_ops {
int (*hdev_attach)(struct hdac_device *hdev);
int (*hdev_detach)(struct hdac_device *hdev);
};
/*
* Lowlevel I/O operators
*/
struct hdac_io_ops {
/* mapped register accesses */
void (*reg_writel)(u32 value, u32 __iomem *addr);
u32 (*reg_readl)(u32 __iomem *addr);
void (*reg_writew)(u16 value, u16 __iomem *addr);
u16 (*reg_readw)(u16 __iomem *addr);
void (*reg_writeb)(u8 value, u8 __iomem *addr);
u8 (*reg_readb)(u8 __iomem *addr);
/* Allocation ops */
int (*dma_alloc_pages)(struct hdac_bus *bus, int type, size_t size,
struct snd_dma_buffer *buf);
void (*dma_free_pages)(struct hdac_bus *bus,
struct snd_dma_buffer *buf);
};
#define HDA_UNSOL_QUEUE_SIZE 64
#define HDA_MAX_CODECS 8 /* limit by controller side */
/*
* CORB/RIRB
*
* Each CORB entry is 4byte, RIRB is 8byte
*/
struct hdac_rb {
__le32 *buf; /* virtual address of CORB/RIRB buffer */
dma_addr_t addr; /* physical address of CORB/RIRB buffer */
unsigned short rp, wp; /* RIRB read/write pointers */
int cmds[HDA_MAX_CODECS]; /* number of pending requests */
u32 res[HDA_MAX_CODECS]; /* last read value */
};
/*
* HD-audio bus base driver
*
* @ppcap: pp capabilities pointer
* @spbcap: SPIB capabilities pointer
* @mlcap: MultiLink capabilities pointer
* @gtscap: gts capabilities pointer
* @drsmcap: dma resume capabilities pointer
* @num_streams: streams supported
* @idx: HDA link index
* @hlink_list: link list of HDA links
* @lock: lock for link and display power mgmt
* @cmd_dma_state: state of cmd DMAs: CORB and RIRB
*/
struct hdac_bus {
struct device *dev;
const struct hdac_bus_ops *ops;
const struct hdac_io_ops *io_ops;
const struct hdac_ext_bus_ops *ext_ops;
/* h/w resources */
unsigned long addr;
void __iomem *remap_addr;
int irq;
void __iomem *ppcap;
void __iomem *spbcap;
void __iomem *mlcap;
void __iomem *gtscap;
void __iomem *drsmcap;
/* codec linked list */
struct list_head codec_list;
unsigned int num_codecs;
/* link caddr -> codec */
struct hdac_device *caddr_tbl[HDA_MAX_CODEC_ADDRESS + 1];
/* unsolicited event queue */
u32 unsol_queue[HDA_UNSOL_QUEUE_SIZE * 2]; /* ring buffer */
unsigned int unsol_rp, unsol_wp;
struct work_struct unsol_work;
/* bit flags of detected codecs */
unsigned long codec_mask;
/* bit flags of powered codecs */
unsigned long codec_powered;
/* CORB/RIRB */
struct hdac_rb corb;
struct hdac_rb rirb;
unsigned int last_cmd[HDA_MAX_CODECS]; /* last sent command */
/* CORB/RIRB and position buffers */
struct snd_dma_buffer rb;
struct snd_dma_buffer posbuf;
/* hdac_stream linked list */
struct list_head stream_list;
/* operation state */
bool chip_init:1; /* h/w initialized */
/* behavior flags */
bool sync_write:1; /* sync after verb write */
bool use_posbuf:1; /* use position buffer */
bool snoop:1; /* enable snooping */
bool align_bdle_4k:1; /* BDLE align 4K boundary */
bool reverse_assign:1; /* assign devices in reverse order */
bool corbrp_self_clear:1; /* CORBRP clears itself after reset */
bool polling_mode:1;
int poll_count;
int bdl_pos_adj; /* BDL position adjustment */
/* locks */
spinlock_t reg_lock;
struct mutex cmd_mutex;
struct mutex lock;
/* DRM component interface */
struct drm_audio_component *audio_component;
long display_power_status;
unsigned long display_power_active;
/* parameters required for enhanced capabilities */
int num_streams;
int idx;
/* link management */
struct list_head hlink_list;
bool cmd_dma_state;
};
int snd_hdac_bus_init(struct hdac_bus *bus, struct device *dev,
const struct hdac_bus_ops *ops,
const struct hdac_io_ops *io_ops);
void snd_hdac_bus_exit(struct hdac_bus *bus);
int snd_hdac_bus_exec_verb(struct hdac_bus *bus, unsigned int addr,
unsigned int cmd, unsigned int *res);
int snd_hdac_bus_exec_verb_unlocked(struct hdac_bus *bus, unsigned int addr,
unsigned int cmd, unsigned int *res);
void snd_hdac_bus_queue_event(struct hdac_bus *bus, u32 res, u32 res_ex);
int snd_hdac_bus_add_device(struct hdac_bus *bus, struct hdac_device *codec);
void snd_hdac_bus_remove_device(struct hdac_bus *bus,
struct hdac_device *codec);
void snd_hdac_bus_process_unsol_events(struct work_struct *work);
static inline void snd_hdac_codec_link_up(struct hdac_device *codec)
{
set_bit(codec->addr, &codec->bus->codec_powered);
}
static inline void snd_hdac_codec_link_down(struct hdac_device *codec)
{
clear_bit(codec->addr, &codec->bus->codec_powered);
}
int snd_hdac_bus_send_cmd(struct hdac_bus *bus, unsigned int val);
int snd_hdac_bus_get_response(struct hdac_bus *bus, unsigned int addr,
unsigned int *res);
int snd_hdac_bus_parse_capabilities(struct hdac_bus *bus);
bool snd_hdac_bus_init_chip(struct hdac_bus *bus, bool full_reset);
void snd_hdac_bus_stop_chip(struct hdac_bus *bus);
void snd_hdac_bus_init_cmd_io(struct hdac_bus *bus);
void snd_hdac_bus_stop_cmd_io(struct hdac_bus *bus);
void snd_hdac_bus_enter_link_reset(struct hdac_bus *bus);
void snd_hdac_bus_exit_link_reset(struct hdac_bus *bus);
int snd_hdac_bus_reset_link(struct hdac_bus *bus, bool full_reset);
void snd_hdac_bus_update_rirb(struct hdac_bus *bus);
int snd_hdac_bus_handle_stream_irq(struct hdac_bus *bus, unsigned int status,
void (*ack)(struct hdac_bus *,
struct hdac_stream *));
int snd_hdac_bus_alloc_stream_pages(struct hdac_bus *bus);
void snd_hdac_bus_free_stream_pages(struct hdac_bus *bus);
/*
* macros for easy use
*/
#define _snd_hdac_chip_writeb(chip, reg, value) \
((chip)->io_ops->reg_writeb(value, (chip)->remap_addr + (reg)))
#define _snd_hdac_chip_readb(chip, reg) \
((chip)->io_ops->reg_readb((chip)->remap_addr + (reg)))
#define _snd_hdac_chip_writew(chip, reg, value) \
((chip)->io_ops->reg_writew(value, (chip)->remap_addr + (reg)))
#define _snd_hdac_chip_readw(chip, reg) \
((chip)->io_ops->reg_readw((chip)->remap_addr + (reg)))
#define _snd_hdac_chip_writel(chip, reg, value) \
((chip)->io_ops->reg_writel(value, (chip)->remap_addr + (reg)))
#define _snd_hdac_chip_readl(chip, reg) \
((chip)->io_ops->reg_readl((chip)->remap_addr + (reg)))
/* read/write a register, pass without AZX_REG_ prefix */
#define snd_hdac_chip_writel(chip, reg, value) \
_snd_hdac_chip_writel(chip, AZX_REG_ ## reg, value)
#define snd_hdac_chip_writew(chip, reg, value) \
_snd_hdac_chip_writew(chip, AZX_REG_ ## reg, value)
#define snd_hdac_chip_writeb(chip, reg, value) \
_snd_hdac_chip_writeb(chip, AZX_REG_ ## reg, value)
#define snd_hdac_chip_readl(chip, reg) \
_snd_hdac_chip_readl(chip, AZX_REG_ ## reg)
#define snd_hdac_chip_readw(chip, reg) \
_snd_hdac_chip_readw(chip, AZX_REG_ ## reg)
#define snd_hdac_chip_readb(chip, reg) \
_snd_hdac_chip_readb(chip, AZX_REG_ ## reg)
/* update a register, pass without AZX_REG_ prefix */
#define snd_hdac_chip_updatel(chip, reg, mask, val) \
snd_hdac_chip_writel(chip, reg, \
(snd_hdac_chip_readl(chip, reg) & ~(mask)) | (val))
#define snd_hdac_chip_updatew(chip, reg, mask, val) \
snd_hdac_chip_writew(chip, reg, \
(snd_hdac_chip_readw(chip, reg) & ~(mask)) | (val))
#define snd_hdac_chip_updateb(chip, reg, mask, val) \
snd_hdac_chip_writeb(chip, reg, \
(snd_hdac_chip_readb(chip, reg) & ~(mask)) | (val))
/*
* HD-audio stream
*/
struct hdac_stream {
struct hdac_bus *bus;
struct snd_dma_buffer bdl; /* BDL buffer */
__le32 *posbuf; /* position buffer pointer */
int direction; /* playback / capture (SNDRV_PCM_STREAM_*) */
unsigned int bufsize; /* size of the play buffer in bytes */
unsigned int period_bytes; /* size of the period in bytes */
unsigned int frags; /* number for period in the play buffer */
unsigned int fifo_size; /* FIFO size */
void __iomem *sd_addr; /* stream descriptor pointer */
u32 sd_int_sta_mask; /* stream int status mask */
/* pcm support */
struct snd_pcm_substream *substream; /* assigned substream,
* set in PCM open
*/
unsigned int format_val; /* format value to be set in the
* controller and the codec
*/
unsigned char stream_tag; /* assigned stream */
unsigned char index; /* stream index */
int assigned_key; /* last device# key assigned to */
bool opened:1;
bool running:1;
bool prepared:1;
bool no_period_wakeup:1;
bool locked:1;
/* timestamp */
unsigned long start_wallclk; /* start + minimum wallclk */
unsigned long period_wallclk; /* wallclk for period */
struct timecounter tc;
struct cyclecounter cc;
int delay_negative_threshold;
struct list_head list;
#ifdef CONFIG_SND_HDA_DSP_LOADER
/* DSP access mutex */
struct mutex dsp_mutex;
#endif
};
void snd_hdac_stream_init(struct hdac_bus *bus, struct hdac_stream *azx_dev,
int idx, int direction, int tag);
struct hdac_stream *snd_hdac_stream_assign(struct hdac_bus *bus,
struct snd_pcm_substream *substream);
void snd_hdac_stream_release(struct hdac_stream *azx_dev);
struct hdac_stream *snd_hdac_get_stream(struct hdac_bus *bus,
int dir, int stream_tag);
int snd_hdac_stream_setup(struct hdac_stream *azx_dev);
void snd_hdac_stream_cleanup(struct hdac_stream *azx_dev);
int snd_hdac_stream_setup_periods(struct hdac_stream *azx_dev);
int snd_hdac_stream_set_params(struct hdac_stream *azx_dev,
unsigned int format_val);
void snd_hdac_stream_start(struct hdac_stream *azx_dev, bool fresh_start);
void snd_hdac_stream_clear(struct hdac_stream *azx_dev);
void snd_hdac_stream_stop(struct hdac_stream *azx_dev);
void snd_hdac_stream_reset(struct hdac_stream *azx_dev);
void snd_hdac_stream_sync_trigger(struct hdac_stream *azx_dev, bool set,
unsigned int streams, unsigned int reg);
void snd_hdac_stream_sync(struct hdac_stream *azx_dev, bool start,
unsigned int streams);
void snd_hdac_stream_timecounter_init(struct hdac_stream *azx_dev,
unsigned int streams);
int snd_hdac_get_stream_stripe_ctl(struct hdac_bus *bus,
struct snd_pcm_substream *substream);
/*
* macros for easy use
*/
#define _snd_hdac_stream_write(type, dev, reg, value) \
((dev)->bus->io_ops->reg_write ## type(value, (dev)->sd_addr + (reg)))
#define _snd_hdac_stream_read(type, dev, reg) \
((dev)->bus->io_ops->reg_read ## type((dev)->sd_addr + (reg)))
/* read/write a register, pass without AZX_REG_ prefix */
#define snd_hdac_stream_writel(dev, reg, value) \
_snd_hdac_stream_write(l, dev, AZX_REG_ ## reg, value)
#define snd_hdac_stream_writew(dev, reg, value) \
_snd_hdac_stream_write(w, dev, AZX_REG_ ## reg, value)
#define snd_hdac_stream_writeb(dev, reg, value) \
_snd_hdac_stream_write(b, dev, AZX_REG_ ## reg, value)
#define snd_hdac_stream_readl(dev, reg) \
_snd_hdac_stream_read(l, dev, AZX_REG_ ## reg)
#define snd_hdac_stream_readw(dev, reg) \
_snd_hdac_stream_read(w, dev, AZX_REG_ ## reg)
#define snd_hdac_stream_readb(dev, reg) \
_snd_hdac_stream_read(b, dev, AZX_REG_ ## reg)
/* update a register, pass without AZX_REG_ prefix */
#define snd_hdac_stream_updatel(dev, reg, mask, val) \
snd_hdac_stream_writel(dev, reg, \
(snd_hdac_stream_readl(dev, reg) & \
~(mask)) | (val))
#define snd_hdac_stream_updatew(dev, reg, mask, val) \
snd_hdac_stream_writew(dev, reg, \
(snd_hdac_stream_readw(dev, reg) & \
~(mask)) | (val))
#define snd_hdac_stream_updateb(dev, reg, mask, val) \
snd_hdac_stream_writeb(dev, reg, \
(snd_hdac_stream_readb(dev, reg) & \
~(mask)) | (val))
#ifdef CONFIG_SND_HDA_DSP_LOADER
/* DSP lock helpers */
#define snd_hdac_dsp_lock_init(dev) mutex_init(&(dev)->dsp_mutex)
#define snd_hdac_dsp_lock(dev) mutex_lock(&(dev)->dsp_mutex)
#define snd_hdac_dsp_unlock(dev) mutex_unlock(&(dev)->dsp_mutex)
#define snd_hdac_stream_is_locked(dev) ((dev)->locked)
/* DSP loader helpers */
int snd_hdac_dsp_prepare(struct hdac_stream *azx_dev, unsigned int format,
unsigned int byte_size, struct snd_dma_buffer *bufp);
void snd_hdac_dsp_trigger(struct hdac_stream *azx_dev, bool start);
void snd_hdac_dsp_cleanup(struct hdac_stream *azx_dev,
struct snd_dma_buffer *dmab);
#else /* CONFIG_SND_HDA_DSP_LOADER */
#define snd_hdac_dsp_lock_init(dev) do {} while (0)
#define snd_hdac_dsp_lock(dev) do {} while (0)
#define snd_hdac_dsp_unlock(dev) do {} while (0)
#define snd_hdac_stream_is_locked(dev) 0
static inline int
snd_hdac_dsp_prepare(struct hdac_stream *azx_dev, unsigned int format,
unsigned int byte_size, struct snd_dma_buffer *bufp)
{
return 0;
}
static inline void snd_hdac_dsp_trigger(struct hdac_stream *azx_dev, bool start)
{
}
static inline void snd_hdac_dsp_cleanup(struct hdac_stream *azx_dev,
struct snd_dma_buffer *dmab)
{
}
#endif /* CONFIG_SND_HDA_DSP_LOADER */
/*
* generic array helpers
*/
void *snd_array_new(struct snd_array *array);
void snd_array_free(struct snd_array *array);
static inline void snd_array_init(struct snd_array *array, unsigned int size,
unsigned int align)
{
array->elem_size = size;
array->alloc_align = align;
}
static inline void *snd_array_elem(struct snd_array *array, unsigned int idx)
{
return array->list + idx * array->elem_size;
}
static inline unsigned int snd_array_index(struct snd_array *array, void *ptr)
{
return (unsigned long)(ptr - array->list) / array->elem_size;
}
/* a helper macro to iterate for each snd_array element */
#define snd_array_for_each(array, idx, ptr) \
for ((idx) = 0, (ptr) = (array)->list; (idx) < (array)->used; \
(ptr) = snd_array_elem(array, ++(idx)))
#endif /* __SOUND_HDAUDIO_H */