[ALSA] pcm core: add prealloc_max file to substream directory to show maximum DMA size

Users ask us many times about the maximum DMA size for PCM devices. This
file gives them a hint in KB.

Signed-off-by: Jaroslav Kysela <perex@suse.cz>
This commit is contained in:
Jaroslav Kysela 2006-10-06 15:12:29 +02:00
parent b66b3cfe6c
commit c7132aeb72
2 changed files with 24 additions and 0 deletions

View file

@ -384,6 +384,7 @@ struct snd_pcm_substream {
struct snd_info_entry *proc_sw_params_entry;
struct snd_info_entry *proc_status_entry;
struct snd_info_entry *proc_prealloc_entry;
struct snd_info_entry *proc_prealloc_max_entry;
#endif
/* misc flags */
unsigned int hw_opened: 1;

View file

@ -101,6 +101,8 @@ int snd_pcm_lib_preallocate_free(struct snd_pcm_substream *substream)
{
snd_pcm_lib_preallocate_dma_free(substream);
#ifdef CONFIG_SND_VERBOSE_PROCFS
snd_info_free_entry(substream->proc_prealloc_max_entry);
substream->proc_prealloc_max_entry = NULL;
snd_info_free_entry(substream->proc_prealloc_entry);
substream->proc_prealloc_entry = NULL;
#endif
@ -141,6 +143,18 @@ static void snd_pcm_lib_preallocate_proc_read(struct snd_info_entry *entry,
snd_iprintf(buffer, "%lu\n", (unsigned long) substream->dma_buffer.bytes / 1024);
}
/*
* read callback for prealloc_max proc file
*
* prints the maximum allowed size in kB.
*/
static void snd_pcm_lib_preallocate_max_proc_read(struct snd_info_entry *entry,
struct snd_info_buffer *buffer)
{
struct snd_pcm_substream *substream = entry->private_data;
snd_iprintf(buffer, "%lu\n", (unsigned long) substream->dma_max / 1024);
}
/*
* write callback for prealloc proc file
*
@ -203,6 +217,15 @@ static inline void preallocate_info_init(struct snd_pcm_substream *substream)
}
}
substream->proc_prealloc_entry = entry;
if ((entry = snd_info_create_card_entry(substream->pcm->card, "prealloc_max", substream->proc_root)) != NULL) {
entry->c.text.read = snd_pcm_lib_preallocate_max_proc_read;
entry->private_data = substream;
if (snd_info_register(entry) < 0) {
snd_info_free_entry(entry);
entry = NULL;
}
}
substream->proc_prealloc_max_entry = entry;
}
#else /* !CONFIG_SND_VERBOSE_PROCFS */