Provide a DOT summary of the DAPM graph in a newly added 'graph.dot' file in debugfs, placed in the card's DAPM directory.

Signed-off-by: Martin Povišer povik+lin@cutebit.org ---

Sample output: https://cutebit.org/macaudio-j274.svg (With unupstreamed sound drivers on Mac mini (2020))

The helper bufprintf macro triggers checkpath.pl:

ERROR: Macros with complex values should be enclosed in parentheses #47: FILE: sound/soc/soc-dapm.c:2235: +#define bufprintf(...) \ + ret += scnprintf(buf + ret, bufsize - ret, __VA_ARGS__)

but adding in {} to the macro body interferes with the if/else constructions later, so I left it as-is.

sound/soc/soc-dapm.c | 141 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 141 insertions(+)

diff --git a/sound/soc/soc-dapm.c b/sound/soc/soc-dapm.c index 73b8bd452ca7..86524908c3fd 100644 --- a/sound/soc/soc-dapm.c +++ b/sound/soc/soc-dapm.c @@ -2210,6 +2210,143 @@ static const struct file_operations dapm_bias_fops = { .llseek = default_llseek, };

+static ssize_t dapm_graph_read_file(struct file *file, char __user *user_buf, + size_t count, loff_t *ppos) +{ + struct snd_soc_card *card = file->private_data; + struct snd_soc_dapm_context *dapm; + struct snd_soc_dapm_path *p; + struct snd_soc_dapm_widget *w; + struct snd_soc_pcm_runtime *rtd; + struct snd_soc_dapm_widget *wdone[16]; + struct snd_soc_dai *dai; + int i, num_wdone = 0, cluster = 0; + char *buf; + ssize_t bufsize; + ssize_t ret = 0; + + bufsize = 1024 * card->num_dapm_widgets; + buf = kmalloc(bufsize, GFP_KERNEL); + if (!buf) + return -ENOMEM; + + mutex_lock(&card->dapm_mutex); + +#define bufprintf(...) \ + ret += scnprintf(buf + ret, bufsize - ret, __VA_ARGS__) + + bufprintf("digraph dapm {\n"); + bufprintf("label="%s";\n", card->name); + + /* + * Print the user-visible PCM devices of the card. + */ + bufprintf("subgraph cluster_%d {\n", cluster++); + bufprintf("label="PCM devices";style=filled;fillcolor=lightgray;\n"); + for_each_card_rtds(card, rtd) { + if (rtd->dai_link->no_pcm) + continue; + + bufprintf("w%pK [label="%d: %s"];\n", rtd, + rtd->pcm->device, rtd->dai_link->name); + } + bufprintf("};\n"); + + /* + * Print the playback/capture widgets of CPU-side DAIs, and link + * them to the PCM devices. Keep a list of already printed + * widgets in 'wdone', so they will be skipped later. Do not put + * these widgets in a component cluster like we will do with + * the other widgets later, since that just clutters the graph. + */ + for_each_card_rtds(card, rtd) { + for_each_rtd_cpu_dais(rtd, i, dai) { + if (dai->playback_widget) { + w = dai->playback_widget; + bufprintf("w%pK [label="%s"];\n", w, w->name); + if (!rtd->dai_link->no_pcm) + bufprintf("w%pK -> w%pK;\n", rtd, w); + wdone[num_wdone] = w; + if (num_wdone < ARRAY_SIZE(wdone)) + num_wdone++; + } + + if (dai->capture_widget) { + w = dai->capture_widget; + bufprintf("w%pK [label="%s"];\n", w, w->name); + if (!rtd->dai_link->no_pcm) + bufprintf("w%pK -> w%pK;\n", w, rtd); + wdone[num_wdone] = w; + if (num_wdone < ARRAY_SIZE(wdone)) + num_wdone++; + } + } + } + + for_each_card_dapms(card, dapm) { + const char *prefix = soc_dapm_prefix(dapm); + + if (dapm != &card->dapm) { + bufprintf("subgraph cluster_%d {\n", cluster++); + if (prefix && dapm->component) + bufprintf("label="%s (%s)";\n", prefix, + dapm->component->name); + else if (dapm->component) + bufprintf("label="%s";\n", + dapm->component->name); + } + + for_each_card_widgets(dapm->card, w) { + const char *name = w->name; + bool skip = false; + + if (w->dapm != dapm) + continue; + + if (list_empty(&w->edges[0]) && list_empty(&w->edges[1])) + continue; + + for (i = 0; i < num_wdone; i++) + if (wdone[i] == w) + skip = true; + if (skip) + continue; + + if (prefix && strlen(name) > strlen(prefix) + 1) + name += strlen(prefix) + 1; + + bufprintf("w%pK [label="%s"];\n", w, name); + } + + if (dapm != &card->dapm) + bufprintf("}\n"); + } + + list_for_each_entry(p, &card->paths, list) { + if (p->name) + bufprintf("w%pK -> w%pK [label="%s"];\n", + p->source, p->sink, p->name); + else + bufprintf("w%pK -> w%pK;\n", p->source, p->sink); + } + + bufprintf("}\n"); +#undef bufprintf + + mutex_unlock(&card->dapm_mutex); + + ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret); + + kfree(buf); + return ret; +} + +static const struct file_operations dapm_graph_fops = { + .open = simple_open, + .read = dapm_graph_read_file, + .llseek = default_llseek, +}; + void snd_soc_dapm_debugfs_init(struct snd_soc_dapm_context *dapm, struct dentry *parent) { @@ -2220,6 +2357,10 @@ void snd_soc_dapm_debugfs_init(struct snd_soc_dapm_context *dapm,

debugfs_create_file("bias_level", 0444, dapm->debugfs_dapm, dapm, &dapm_bias_fops); + + if (dapm == &dapm->card->dapm) + debugfs_create_file("graph.dot", 0444, dapm->debugfs_dapm, + dapm->card, &dapm_graph_fops); }

static void dapm_debugfs_add_widget(struct snd_soc_dapm_widget *w)