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Diffstat (limited to 'sound/aoa/soundbus/soundbus.h')
| -rw-r--r-- | sound/aoa/soundbus/soundbus.h | 201 |
1 files changed, 201 insertions, 0 deletions
diff --git a/sound/aoa/soundbus/soundbus.h b/sound/aoa/soundbus/soundbus.h new file mode 100644 index 000000000..3a99c1f1a --- /dev/null +++ b/sound/aoa/soundbus/soundbus.h @@ -0,0 +1,201 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * soundbus generic definitions + * + * Copyright 2006 Johannes Berg <johannes@sipsolutions.net> + */ +#ifndef __SOUNDBUS_H +#define __SOUNDBUS_H + +#include <linux/of_device.h> +#include <sound/pcm.h> +#include <linux/list.h> + + +/* When switching from master to slave or the other way around, + * you don't want to have the codec chip acting as clock source + * while the bus still is. + * More importantly, while switch from slave to master, you need + * to turn off the chip's master function first, but then there's + * no clock for a while and other chips might reset, so we notify + * their drivers after having switched. + * The constants here are codec-point of view, so when we switch + * the soundbus to master we tell the codec we're going to switch + * and give it CLOCK_SWITCH_PREPARE_SLAVE! + */ +enum clock_switch { + CLOCK_SWITCH_PREPARE_SLAVE, + CLOCK_SWITCH_PREPARE_MASTER, + CLOCK_SWITCH_SLAVE, + CLOCK_SWITCH_MASTER, + CLOCK_SWITCH_NOTIFY, +}; + +/* information on a transfer the codec can take */ +struct transfer_info { + u64 formats; /* SNDRV_PCM_FMTBIT_* */ + unsigned int rates; /* SNDRV_PCM_RATE_* */ + /* flags */ + u32 transfer_in:1, /* input = 1, output = 0 */ + must_be_clock_source:1; + /* for codecs to distinguish among their TIs */ + int tag; +}; + +struct codec_info_item { + struct codec_info *codec; + void *codec_data; + struct soundbus_dev *sdev; + /* internal, to be used by the soundbus provider */ + struct list_head list; +}; + +/* for prepare, where the codecs need to know + * what we're going to drive the bus with */ +struct bus_info { + /* see below */ + int sysclock_factor; + int bus_factor; +}; + +/* information on the codec itself, plus function pointers */ +struct codec_info { + /* the module this lives in */ + struct module *owner; + + /* supported transfer possibilities, array terminated by + * formats or rates being 0. */ + struct transfer_info *transfers; + + /* Master clock speed factor + * to be used (master clock speed = sysclock_factor * sampling freq) + * Unused if the soundbus provider has no such notion. + */ + int sysclock_factor; + + /* Bus factor, bus clock speed = bus_factor * sampling freq) + * Unused if the soundbus provider has no such notion. + */ + int bus_factor; + + /* operations */ + /* clock switching, see above */ + int (*switch_clock)(struct codec_info_item *cii, + enum clock_switch clock); + + /* called for each transfer_info when the user + * opens the pcm device to determine what the + * hardware can support at this point in time. + * That can depend on other user-switchable controls. + * Return 1 if usable, 0 if not. + * out points to another instance of a transfer_info + * which is initialised to the values in *ti, and + * it's format and rate values can be modified by + * the callback if it is necessary to further restrict + * the formats that can be used at the moment, for + * example when one codec has multiple logical codec + * info structs for multiple inputs. + */ + int (*usable)(struct codec_info_item *cii, + struct transfer_info *ti, + struct transfer_info *out); + + /* called when pcm stream is opened, probably not implemented + * most of the time since it isn't too useful */ + int (*open)(struct codec_info_item *cii, + struct snd_pcm_substream *substream); + + /* called when the pcm stream is closed, at this point + * the user choices can all be unlocked (see below) */ + int (*close)(struct codec_info_item *cii, + struct snd_pcm_substream *substream); + + /* if the codec must forbid some user choices because + * they are not valid with the substream/transfer info, + * it must do so here. Example: no digital output for + * incompatible framerate, say 8KHz, on Onyx. + * If the selected stuff in the substream is NOT + * compatible, you have to reject this call! */ + int (*prepare)(struct codec_info_item *cii, + struct bus_info *bi, + struct snd_pcm_substream *substream); + + /* start() is called before data is pushed to the codec. + * Note that start() must be atomic! */ + int (*start)(struct codec_info_item *cii, + struct snd_pcm_substream *substream); + + /* stop() is called after data is no longer pushed to the codec. + * Note that stop() must be atomic! */ + int (*stop)(struct codec_info_item *cii, + struct snd_pcm_substream *substream); + + int (*suspend)(struct codec_info_item *cii, pm_message_t state); + int (*resume)(struct codec_info_item *cii); +}; + +/* information on a soundbus device */ +struct soundbus_dev { + /* the bus it belongs to */ + struct list_head onbuslist; + + /* the of device it represents */ + struct platform_device ofdev; + + /* what modules go by */ + char modalias[32]; + + /* These fields must be before attach_codec can be called. + * They should be set by the owner of the alsa card object + * that is needed, and whoever sets them must make sure + * that they are unique within that alsa card object. */ + char *pcmname; + int pcmid; + + /* this is assigned by the soundbus provider in attach_codec */ + struct snd_pcm *pcm; + + /* operations */ + /* attach a codec to this soundbus, give the alsa + * card object the PCMs for this soundbus should be in. + * The 'data' pointer must be unique, it is used as the + * key for detach_codec(). */ + int (*attach_codec)(struct soundbus_dev *dev, struct snd_card *card, + struct codec_info *ci, void *data); + void (*detach_codec)(struct soundbus_dev *dev, void *data); + /* TODO: suspend/resume */ + + /* private for the soundbus provider */ + struct list_head codec_list; + u32 have_out:1, have_in:1; +}; +#define to_soundbus_device(d) container_of(d, struct soundbus_dev, ofdev.dev) +#define of_to_soundbus_device(d) container_of(d, struct soundbus_dev, ofdev) + +extern int soundbus_add_one(struct soundbus_dev *dev); +extern void soundbus_remove_one(struct soundbus_dev *dev); + +extern struct soundbus_dev *soundbus_dev_get(struct soundbus_dev *dev); +extern void soundbus_dev_put(struct soundbus_dev *dev); + +struct soundbus_driver { + char *name; + struct module *owner; + + /* we don't implement any matching at all */ + + int (*probe)(struct soundbus_dev* dev); + int (*remove)(struct soundbus_dev* dev); + + int (*shutdown)(struct soundbus_dev* dev); + + struct device_driver driver; +}; +#define to_soundbus_driver(drv) container_of(drv,struct soundbus_driver, driver) + +extern int soundbus_register_driver(struct soundbus_driver *drv); +extern void soundbus_unregister_driver(struct soundbus_driver *drv); + +extern struct attribute *soundbus_dev_attrs[]; + +#endif /* __SOUNDBUS_H */ |