1 /* SPDX-License-Identifier: GPL-2.0 */
6 #ifndef __SOUND_HDAUDIO_H
7 #define __SOUND_HDAUDIO_H
9 #include <linux/device.h>
10 #include <linux/interrupt.h>
12 #include <linux/pm_runtime.h>
13 #include <linux/timecounter.h>
14 #include <sound/core.h>
15 #include <sound/pcm.h>
16 #include <sound/memalloc.h>
17 #include <sound/hda_verbs.h>
18 #include <drm/i915_component.h>
21 typedef u16 hda_nid_t;
27 struct hdac_widget_tree;
33 extern struct bus_type snd_hda_bus_type;
41 unsigned int elem_size;
42 unsigned int alloc_align;
47 * HD-audio codec base device
53 unsigned int addr; /* codec address */
54 struct list_head list; /* list point for bus codec_list */
56 hda_nid_t afg; /* AFG node id */
57 hda_nid_t mfg; /* MFG node id */
60 unsigned int vendor_id;
61 unsigned int subsystem_id;
62 unsigned int revision_id;
63 unsigned int afg_function_id;
64 unsigned int mfg_function_id;
65 unsigned int afg_unsol:1;
66 unsigned int mfg_unsol:1;
68 unsigned int power_caps; /* FG power caps */
70 const char *vendor_name; /* codec vendor name */
71 const char *chip_name; /* codec chip name */
73 /* verb exec op override */
74 int (*exec_verb)(struct hdac_device *dev, unsigned int cmd,
75 unsigned int flags, unsigned int *res);
78 unsigned int num_nodes;
79 hda_nid_t start_nid, end_nid;
82 atomic_t in_pm; /* suspend/resume being performed */
85 struct mutex widget_lock;
86 struct hdac_widget_tree *widgets;
89 struct regmap *regmap;
90 struct mutex regmap_lock;
91 struct snd_array vendor_verbs;
92 bool lazy_cache:1; /* don't wake up for writes */
93 bool caps_overwriting:1; /* caps overwrite being in process */
94 bool cache_coef:1; /* cache COEF read/write too */
97 /* device/driver type used for matching */
105 SND_SKL_PCI_BIND_AUTO, /* automatic selection based on pci class */
106 SND_SKL_PCI_BIND_LEGACY,/* bind only with legacy driver */
107 SND_SKL_PCI_BIND_ASOC /* bind only with ASoC driver */
112 HDA_INPUT, HDA_OUTPUT
115 #define dev_to_hdac_dev(_dev) container_of(_dev, struct hdac_device, dev)
117 int snd_hdac_device_init(struct hdac_device *dev, struct hdac_bus *bus,
118 const char *name, unsigned int addr);
119 void snd_hdac_device_exit(struct hdac_device *dev);
120 int snd_hdac_device_register(struct hdac_device *codec);
121 void snd_hdac_device_unregister(struct hdac_device *codec);
122 int snd_hdac_device_set_chip_name(struct hdac_device *codec, const char *name);
123 int snd_hdac_codec_modalias(struct hdac_device *hdac, char *buf, size_t size);
125 int snd_hdac_refresh_widgets(struct hdac_device *codec);
127 int snd_hdac_read(struct hdac_device *codec, hda_nid_t nid,
128 unsigned int verb, unsigned int parm, unsigned int *res);
129 int _snd_hdac_read_parm(struct hdac_device *codec, hda_nid_t nid, int parm,
131 int snd_hdac_read_parm_uncached(struct hdac_device *codec, hda_nid_t nid,
133 int snd_hdac_override_parm(struct hdac_device *codec, hda_nid_t nid,
134 unsigned int parm, unsigned int val);
135 int snd_hdac_get_connections(struct hdac_device *codec, hda_nid_t nid,
136 hda_nid_t *conn_list, int max_conns);
137 int snd_hdac_get_sub_nodes(struct hdac_device *codec, hda_nid_t nid,
138 hda_nid_t *start_id);
139 unsigned int snd_hdac_calc_stream_format(unsigned int rate,
140 unsigned int channels,
141 snd_pcm_format_t format,
143 unsigned short spdif_ctls);
144 int snd_hdac_query_supported_pcm(struct hdac_device *codec, hda_nid_t nid,
145 u32 *ratesp, u64 *formatsp, unsigned int *bpsp);
146 bool snd_hdac_is_supported_format(struct hdac_device *codec, hda_nid_t nid,
147 unsigned int format);
149 int snd_hdac_codec_read(struct hdac_device *hdac, hda_nid_t nid,
150 int flags, unsigned int verb, unsigned int parm);
151 int snd_hdac_codec_write(struct hdac_device *hdac, hda_nid_t nid,
152 int flags, unsigned int verb, unsigned int parm);
153 bool snd_hdac_check_power_state(struct hdac_device *hdac,
154 hda_nid_t nid, unsigned int target_state);
155 unsigned int snd_hdac_sync_power_state(struct hdac_device *hdac,
156 hda_nid_t nid, unsigned int target_state);
158 * snd_hdac_read_parm - read a codec parameter
159 * @codec: the codec object
160 * @nid: NID to read a parameter
161 * @parm: parameter to read
163 * Returns -1 for error. If you need to distinguish the error more
164 * strictly, use _snd_hdac_read_parm() directly.
166 static inline int snd_hdac_read_parm(struct hdac_device *codec, hda_nid_t nid,
171 return _snd_hdac_read_parm(codec, nid, parm, &val) < 0 ? -1 : val;
175 int snd_hdac_power_up(struct hdac_device *codec);
176 int snd_hdac_power_down(struct hdac_device *codec);
177 int snd_hdac_power_up_pm(struct hdac_device *codec);
178 int snd_hdac_power_down_pm(struct hdac_device *codec);
179 int snd_hdac_keep_power_up(struct hdac_device *codec);
181 /* call this at entering into suspend/resume callbacks in codec driver */
182 static inline void snd_hdac_enter_pm(struct hdac_device *codec)
184 atomic_inc(&codec->in_pm);
187 /* call this at leaving from suspend/resume callbacks in codec driver */
188 static inline void snd_hdac_leave_pm(struct hdac_device *codec)
190 atomic_dec(&codec->in_pm);
193 static inline bool snd_hdac_is_in_pm(struct hdac_device *codec)
195 return atomic_read(&codec->in_pm);
198 static inline bool snd_hdac_is_power_on(struct hdac_device *codec)
200 return !pm_runtime_suspended(&codec->dev);
203 static inline int snd_hdac_power_up(struct hdac_device *codec) { return 0; }
204 static inline int snd_hdac_power_down(struct hdac_device *codec) { return 0; }
205 static inline int snd_hdac_power_up_pm(struct hdac_device *codec) { return 0; }
206 static inline int snd_hdac_power_down_pm(struct hdac_device *codec) { return 0; }
207 static inline int snd_hdac_keep_power_up(struct hdac_device *codec) { return 0; }
208 static inline void snd_hdac_enter_pm(struct hdac_device *codec) {}
209 static inline void snd_hdac_leave_pm(struct hdac_device *codec) {}
210 static inline bool snd_hdac_is_in_pm(struct hdac_device *codec) { return false; }
211 static inline bool snd_hdac_is_power_on(struct hdac_device *codec) { return true; }
215 * HD-audio codec base driver
218 struct device_driver driver;
220 const struct hda_device_id *id_table;
221 int (*match)(struct hdac_device *dev, struct hdac_driver *drv);
222 void (*unsol_event)(struct hdac_device *dev, unsigned int event);
224 /* fields used by ext bus APIs */
225 int (*probe)(struct hdac_device *dev);
226 int (*remove)(struct hdac_device *dev);
227 void (*shutdown)(struct hdac_device *dev);
230 #define drv_to_hdac_driver(_drv) container_of(_drv, struct hdac_driver, driver)
232 const struct hda_device_id *
233 hdac_get_device_id(struct hdac_device *hdev, struct hdac_driver *drv);
238 struct hdac_bus_ops {
239 /* send a single command */
240 int (*command)(struct hdac_bus *bus, unsigned int cmd);
241 /* get a response from the last command */
242 int (*get_response)(struct hdac_bus *bus, unsigned int addr,
247 * ops used for ASoC HDA codec drivers
249 struct hdac_ext_bus_ops {
250 int (*hdev_attach)(struct hdac_device *hdev);
251 int (*hdev_detach)(struct hdac_device *hdev);
254 #define HDA_UNSOL_QUEUE_SIZE 64
255 #define HDA_MAX_CODECS 8 /* limit by controller side */
260 * Each CORB entry is 4byte, RIRB is 8byte
263 __le32 *buf; /* virtual address of CORB/RIRB buffer */
264 dma_addr_t addr; /* physical address of CORB/RIRB buffer */
265 unsigned short rp, wp; /* RIRB read/write pointers */
266 int cmds[HDA_MAX_CODECS]; /* number of pending requests */
267 u32 res[HDA_MAX_CODECS]; /* last read value */
271 * HD-audio bus base driver
273 * @ppcap: pp capabilities pointer
274 * @spbcap: SPIB capabilities pointer
275 * @mlcap: MultiLink capabilities pointer
276 * @gtscap: gts capabilities pointer
277 * @drsmcap: dma resume capabilities pointer
278 * @num_streams: streams supported
279 * @idx: HDA link index
280 * @hlink_list: link list of HDA links
281 * @lock: lock for link and display power mgmt
282 * @cmd_dma_state: state of cmd DMAs: CORB and RIRB
286 const struct hdac_bus_ops *ops;
287 const struct hdac_ext_bus_ops *ext_ops;
291 void __iomem *remap_addr;
295 void __iomem *spbcap;
297 void __iomem *gtscap;
298 void __iomem *drsmcap;
300 /* codec linked list */
301 struct list_head codec_list;
302 unsigned int num_codecs;
304 /* link caddr -> codec */
305 struct hdac_device *caddr_tbl[HDA_MAX_CODEC_ADDRESS + 1];
307 /* unsolicited event queue */
308 u32 unsol_queue[HDA_UNSOL_QUEUE_SIZE * 2]; /* ring buffer */
309 unsigned int unsol_rp, unsol_wp;
310 struct work_struct unsol_work;
312 /* bit flags of detected codecs */
313 unsigned long codec_mask;
315 /* bit flags of powered codecs */
316 unsigned long codec_powered;
321 unsigned int last_cmd[HDA_MAX_CODECS]; /* last sent command */
322 wait_queue_head_t rirb_wq;
324 /* CORB/RIRB and position buffers */
325 struct snd_dma_buffer rb;
326 struct snd_dma_buffer posbuf;
327 int dma_type; /* SNDRV_DMA_TYPE_XXX for CORB/RIRB */
329 /* hdac_stream linked list */
330 struct list_head stream_list;
332 /* operation state */
333 bool chip_init:1; /* h/w initialized */
336 bool aligned_mmio:1; /* aligned MMIO access */
337 bool sync_write:1; /* sync after verb write */
338 bool use_posbuf:1; /* use position buffer */
339 bool snoop:1; /* enable snooping */
340 bool align_bdle_4k:1; /* BDLE align 4K boundary */
341 bool reverse_assign:1; /* assign devices in reverse order */
342 bool corbrp_self_clear:1; /* CORBRP clears itself after reset */
344 bool needs_damn_long_delay:1;
348 int bdl_pos_adj; /* BDL position adjustment */
350 /* delay time in us for dma stop */
351 unsigned int dma_stop_delay;
355 struct mutex cmd_mutex;
358 /* DRM component interface */
359 struct drm_audio_component *audio_component;
360 long display_power_status;
361 unsigned long display_power_active;
363 /* parameters required for enhanced capabilities */
367 /* link management */
368 struct list_head hlink_list;
371 /* factor used to derive STRIPE control value */
372 unsigned int sdo_limit;
375 int snd_hdac_bus_init(struct hdac_bus *bus, struct device *dev,
376 const struct hdac_bus_ops *ops);
377 void snd_hdac_bus_exit(struct hdac_bus *bus);
378 int snd_hdac_bus_exec_verb_unlocked(struct hdac_bus *bus, unsigned int addr,
379 unsigned int cmd, unsigned int *res);
381 static inline void snd_hdac_codec_link_up(struct hdac_device *codec)
383 set_bit(codec->addr, &codec->bus->codec_powered);
386 static inline void snd_hdac_codec_link_down(struct hdac_device *codec)
388 clear_bit(codec->addr, &codec->bus->codec_powered);
391 int snd_hdac_bus_send_cmd(struct hdac_bus *bus, unsigned int val);
392 int snd_hdac_bus_get_response(struct hdac_bus *bus, unsigned int addr,
394 int snd_hdac_bus_parse_capabilities(struct hdac_bus *bus);
396 bool snd_hdac_bus_init_chip(struct hdac_bus *bus, bool full_reset);
397 void snd_hdac_bus_stop_chip(struct hdac_bus *bus);
398 void snd_hdac_bus_init_cmd_io(struct hdac_bus *bus);
399 void snd_hdac_bus_stop_cmd_io(struct hdac_bus *bus);
400 void snd_hdac_bus_enter_link_reset(struct hdac_bus *bus);
401 void snd_hdac_bus_exit_link_reset(struct hdac_bus *bus);
402 int snd_hdac_bus_reset_link(struct hdac_bus *bus, bool full_reset);
404 void snd_hdac_bus_update_rirb(struct hdac_bus *bus);
405 int snd_hdac_bus_handle_stream_irq(struct hdac_bus *bus, unsigned int status,
406 void (*ack)(struct hdac_bus *,
407 struct hdac_stream *));
409 int snd_hdac_bus_alloc_stream_pages(struct hdac_bus *bus);
410 void snd_hdac_bus_free_stream_pages(struct hdac_bus *bus);
412 #ifdef CONFIG_SND_HDA_ALIGNED_MMIO
413 unsigned int snd_hdac_aligned_read(void __iomem *addr, unsigned int mask);
414 void snd_hdac_aligned_write(unsigned int val, void __iomem *addr,
416 #define snd_hdac_aligned_mmio(bus) (bus)->aligned_mmio
418 #define snd_hdac_aligned_mmio(bus) false
419 #define snd_hdac_aligned_read(addr, mask) 0
420 #define snd_hdac_aligned_write(val, addr, mask) do {} while (0)
423 static inline void snd_hdac_reg_writeb(struct hdac_bus *bus, void __iomem *addr,
426 if (snd_hdac_aligned_mmio(bus))
427 snd_hdac_aligned_write(val, addr, 0xff);
432 static inline void snd_hdac_reg_writew(struct hdac_bus *bus, void __iomem *addr,
435 if (snd_hdac_aligned_mmio(bus))
436 snd_hdac_aligned_write(val, addr, 0xffff);
441 static inline u8 snd_hdac_reg_readb(struct hdac_bus *bus, void __iomem *addr)
443 return snd_hdac_aligned_mmio(bus) ?
444 snd_hdac_aligned_read(addr, 0xff) : readb(addr);
447 static inline u16 snd_hdac_reg_readw(struct hdac_bus *bus, void __iomem *addr)
449 return snd_hdac_aligned_mmio(bus) ?
450 snd_hdac_aligned_read(addr, 0xffff) : readw(addr);
453 #define snd_hdac_reg_writel(bus, addr, val) writel(val, addr)
454 #define snd_hdac_reg_readl(bus, addr) readl(addr)
457 * macros for easy use
459 #define _snd_hdac_chip_writeb(chip, reg, value) \
460 snd_hdac_reg_writeb(chip, (chip)->remap_addr + (reg), value)
461 #define _snd_hdac_chip_readb(chip, reg) \
462 snd_hdac_reg_readb(chip, (chip)->remap_addr + (reg))
463 #define _snd_hdac_chip_writew(chip, reg, value) \
464 snd_hdac_reg_writew(chip, (chip)->remap_addr + (reg), value)
465 #define _snd_hdac_chip_readw(chip, reg) \
466 snd_hdac_reg_readw(chip, (chip)->remap_addr + (reg))
467 #define _snd_hdac_chip_writel(chip, reg, value) \
468 snd_hdac_reg_writel(chip, (chip)->remap_addr + (reg), value)
469 #define _snd_hdac_chip_readl(chip, reg) \
470 snd_hdac_reg_readl(chip, (chip)->remap_addr + (reg))
472 /* read/write a register, pass without AZX_REG_ prefix */
473 #define snd_hdac_chip_writel(chip, reg, value) \
474 _snd_hdac_chip_writel(chip, AZX_REG_ ## reg, value)
475 #define snd_hdac_chip_writew(chip, reg, value) \
476 _snd_hdac_chip_writew(chip, AZX_REG_ ## reg, value)
477 #define snd_hdac_chip_writeb(chip, reg, value) \
478 _snd_hdac_chip_writeb(chip, AZX_REG_ ## reg, value)
479 #define snd_hdac_chip_readl(chip, reg) \
480 _snd_hdac_chip_readl(chip, AZX_REG_ ## reg)
481 #define snd_hdac_chip_readw(chip, reg) \
482 _snd_hdac_chip_readw(chip, AZX_REG_ ## reg)
483 #define snd_hdac_chip_readb(chip, reg) \
484 _snd_hdac_chip_readb(chip, AZX_REG_ ## reg)
486 /* update a register, pass without AZX_REG_ prefix */
487 #define snd_hdac_chip_updatel(chip, reg, mask, val) \
488 snd_hdac_chip_writel(chip, reg, \
489 (snd_hdac_chip_readl(chip, reg) & ~(mask)) | (val))
490 #define snd_hdac_chip_updatew(chip, reg, mask, val) \
491 snd_hdac_chip_writew(chip, reg, \
492 (snd_hdac_chip_readw(chip, reg) & ~(mask)) | (val))
493 #define snd_hdac_chip_updateb(chip, reg, mask, val) \
494 snd_hdac_chip_writeb(chip, reg, \
495 (snd_hdac_chip_readb(chip, reg) & ~(mask)) | (val))
501 struct hdac_bus *bus;
502 struct snd_dma_buffer bdl; /* BDL buffer */
503 __le32 *posbuf; /* position buffer pointer */
504 int direction; /* playback / capture (SNDRV_PCM_STREAM_*) */
506 unsigned int bufsize; /* size of the play buffer in bytes */
507 unsigned int period_bytes; /* size of the period in bytes */
508 unsigned int frags; /* number for period in the play buffer */
509 unsigned int fifo_size; /* FIFO size */
511 void __iomem *sd_addr; /* stream descriptor pointer */
513 u32 sd_int_sta_mask; /* stream int status mask */
516 struct snd_pcm_substream *substream; /* assigned substream,
519 struct snd_compr_stream *cstream;
520 unsigned int format_val; /* format value to be set in the
521 * controller and the codec
523 unsigned char stream_tag; /* assigned stream */
524 unsigned char index; /* stream index */
525 int assigned_key; /* last device# key assigned to */
530 bool no_period_wakeup:1;
532 bool stripe:1; /* apply stripe control */
536 unsigned long start_wallclk; /* start + minimum wallclk */
537 unsigned long period_wallclk; /* wallclk for period */
538 struct timecounter tc;
539 struct cyclecounter cc;
540 int delay_negative_threshold;
542 struct list_head list;
543 #ifdef CONFIG_SND_HDA_DSP_LOADER
544 /* DSP access mutex */
545 struct mutex dsp_mutex;
549 void snd_hdac_stream_init(struct hdac_bus *bus, struct hdac_stream *azx_dev,
550 int idx, int direction, int tag);
551 struct hdac_stream *snd_hdac_stream_assign(struct hdac_bus *bus,
552 struct snd_pcm_substream *substream);
553 void snd_hdac_stream_release(struct hdac_stream *azx_dev);
554 struct hdac_stream *snd_hdac_get_stream(struct hdac_bus *bus,
555 int dir, int stream_tag);
557 int snd_hdac_stream_setup(struct hdac_stream *azx_dev);
558 void snd_hdac_stream_cleanup(struct hdac_stream *azx_dev);
559 int snd_hdac_stream_setup_periods(struct hdac_stream *azx_dev);
560 int snd_hdac_stream_set_params(struct hdac_stream *azx_dev,
561 unsigned int format_val);
562 void snd_hdac_stream_start(struct hdac_stream *azx_dev, bool fresh_start);
563 void snd_hdac_stream_clear(struct hdac_stream *azx_dev);
564 void snd_hdac_stream_stop(struct hdac_stream *azx_dev);
565 void snd_hdac_stream_reset(struct hdac_stream *azx_dev);
566 void snd_hdac_stream_sync_trigger(struct hdac_stream *azx_dev, bool set,
567 unsigned int streams, unsigned int reg);
568 void snd_hdac_stream_sync(struct hdac_stream *azx_dev, bool start,
569 unsigned int streams);
570 void snd_hdac_stream_timecounter_init(struct hdac_stream *azx_dev,
571 unsigned int streams);
572 int snd_hdac_get_stream_stripe_ctl(struct hdac_bus *bus,
573 struct snd_pcm_substream *substream);
576 * macros for easy use
578 /* read/write a register, pass without AZX_REG_ prefix */
579 #define snd_hdac_stream_writel(dev, reg, value) \
580 snd_hdac_reg_writel((dev)->bus, (dev)->sd_addr + AZX_REG_ ## reg, value)
581 #define snd_hdac_stream_writew(dev, reg, value) \
582 snd_hdac_reg_writew((dev)->bus, (dev)->sd_addr + AZX_REG_ ## reg, value)
583 #define snd_hdac_stream_writeb(dev, reg, value) \
584 snd_hdac_reg_writeb((dev)->bus, (dev)->sd_addr + AZX_REG_ ## reg, value)
585 #define snd_hdac_stream_readl(dev, reg) \
586 snd_hdac_reg_readl((dev)->bus, (dev)->sd_addr + AZX_REG_ ## reg)
587 #define snd_hdac_stream_readw(dev, reg) \
588 snd_hdac_reg_readw((dev)->bus, (dev)->sd_addr + AZX_REG_ ## reg)
589 #define snd_hdac_stream_readb(dev, reg) \
590 snd_hdac_reg_readb((dev)->bus, (dev)->sd_addr + AZX_REG_ ## reg)
592 /* update a register, pass without AZX_REG_ prefix */
593 #define snd_hdac_stream_updatel(dev, reg, mask, val) \
594 snd_hdac_stream_writel(dev, reg, \
595 (snd_hdac_stream_readl(dev, reg) & \
597 #define snd_hdac_stream_updatew(dev, reg, mask, val) \
598 snd_hdac_stream_writew(dev, reg, \
599 (snd_hdac_stream_readw(dev, reg) & \
601 #define snd_hdac_stream_updateb(dev, reg, mask, val) \
602 snd_hdac_stream_writeb(dev, reg, \
603 (snd_hdac_stream_readb(dev, reg) & \
606 #ifdef CONFIG_SND_HDA_DSP_LOADER
607 /* DSP lock helpers */
608 #define snd_hdac_dsp_lock_init(dev) mutex_init(&(dev)->dsp_mutex)
609 #define snd_hdac_dsp_lock(dev) mutex_lock(&(dev)->dsp_mutex)
610 #define snd_hdac_dsp_unlock(dev) mutex_unlock(&(dev)->dsp_mutex)
611 #define snd_hdac_stream_is_locked(dev) ((dev)->locked)
612 /* DSP loader helpers */
613 int snd_hdac_dsp_prepare(struct hdac_stream *azx_dev, unsigned int format,
614 unsigned int byte_size, struct snd_dma_buffer *bufp);
615 void snd_hdac_dsp_trigger(struct hdac_stream *azx_dev, bool start);
616 void snd_hdac_dsp_cleanup(struct hdac_stream *azx_dev,
617 struct snd_dma_buffer *dmab);
618 #else /* CONFIG_SND_HDA_DSP_LOADER */
619 #define snd_hdac_dsp_lock_init(dev) do {} while (0)
620 #define snd_hdac_dsp_lock(dev) do {} while (0)
621 #define snd_hdac_dsp_unlock(dev) do {} while (0)
622 #define snd_hdac_stream_is_locked(dev) 0
625 snd_hdac_dsp_prepare(struct hdac_stream *azx_dev, unsigned int format,
626 unsigned int byte_size, struct snd_dma_buffer *bufp)
631 static inline void snd_hdac_dsp_trigger(struct hdac_stream *azx_dev, bool start)
635 static inline void snd_hdac_dsp_cleanup(struct hdac_stream *azx_dev,
636 struct snd_dma_buffer *dmab)
639 #endif /* CONFIG_SND_HDA_DSP_LOADER */
643 * generic array helpers
645 void *snd_array_new(struct snd_array *array);
646 void snd_array_free(struct snd_array *array);
647 static inline void snd_array_init(struct snd_array *array, unsigned int size,
650 array->elem_size = size;
651 array->alloc_align = align;
654 static inline void *snd_array_elem(struct snd_array *array, unsigned int idx)
656 return array->list + idx * array->elem_size;
659 static inline unsigned int snd_array_index(struct snd_array *array, void *ptr)
661 return (unsigned long)(ptr - array->list) / array->elem_size;
664 /* a helper macro to iterate for each snd_array element */
665 #define snd_array_for_each(array, idx, ptr) \
666 for ((idx) = 0, (ptr) = (array)->list; (idx) < (array)->used; \
667 (ptr) = snd_array_elem(array, ++(idx)))
669 #endif /* __SOUND_HDAUDIO_H */