/* * soundbus generic definitions * * Copyright 2006 Johannes Berg * * GPL v2, can be found in COPYING. */ #ifndef __SOUNDBUS_H #define __SOUNDBUS_H #include #include #include /* 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 (*suspend)(struct soundbus_dev* dev, pm_message_t state); int (*resume)(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 device_attribute soundbus_dev_attrs[]; #endif /* __SOUNDBUS_H */