ASoC: dpcm: Add debugFS support for DPCM

Add debugFS files for DPCM link management information.

Signed-off-by: Liam Girdwood <lrg@ti.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

2 files changed, 163 insertions, 0 deletions

diff --git a/sound/soc/soc-core.c b/sound/soc/soc-core.c
index 01220a5cf43e..201a4d003b9a 100644
--- a/sound/soc/soc-core.c
+++ b/sound/soc/soc-core.c
@@ -1187,6 +1187,17 @@ static int soc_post_component_init(struct snd_soc_card *card,
                 dev_err(codec->dev,
                         "asoc: failed to add codec sysfs files: %d\n", ret);
 
+#ifdef CONFIG_DEBUG_FS
+        /* add DPCM sysfs entries */
+        if (!dai_link->dynamic)
+                goto out;
+
+        ret = soc_dpcm_debugfs_add(rtd);
+        if (ret < 0)
+                dev_err(rtd->dev, "asoc: failed to add dpcm sysfs entries: %d\n", ret);
+
+out:
+#endif
         return 0;
 }
 
diff --git a/sound/soc/soc-pcm.c b/sound/soc/soc-pcm.c
index 458f116aa570..a1d4426a99d9 100644
--- a/sound/soc/soc-pcm.c
+++ b/sound/soc/soc-pcm.c
@@ -23,6 +23,7 @@
 #include <linux/slab.h>
 #include <linux/workqueue.h>
 #include <linux/export.h>
+#include <linux/debugfs.h>
 #include <sound/core.h>
 #include <sound/pcm.h>
 #include <sound/pcm_params.h>
@@ -690,6 +691,10 @@ static int dpcm_be_connect(struct snd_soc_pcm_runtime *fe,
                         stream ? "capture" : "playback",  fe->dai_link->name,
                         stream ? "<-" : "->", be->dai_link->name);
 
+#ifdef CONFIG_DEBUG_FS
+        dpcm->debugfs_state = debugfs_create_u32(be->dai_link->name, 0644,
+                        fe->debugfs_dpcm_root, &dpcm->state);
+#endif
         return 1;
 }
 
@@ -741,6 +746,9 @@ static void dpcm_be_disconnect(struct snd_soc_pcm_runtime *fe, int stream)
                 /* BEs still alive need new FE */
                 dpcm_be_reparent(fe, dpcm->be, stream);
 
+#ifdef CONFIG_DEBUG_FS
+                debugfs_remove(dpcm->debugfs_state);
+#endif
                 list_del(&dpcm->list_be);
                 list_del(&dpcm->list_fe);
                 kfree(dpcm);
@@ -1890,3 +1898,147 @@ int snd_soc_dpcm_can_be_params(struct snd_soc_pcm_runtime *fe,
         return 1;
 }
 EXPORT_SYMBOL_GPL(snd_soc_dpcm_can_be_params);
+
+#ifdef CONFIG_DEBUG_FS
+static char *dpcm_state_string(enum snd_soc_dpcm_state state)
+{
+        switch (state) {
+        case SND_SOC_DPCM_STATE_NEW:
+                return "new";
+        case SND_SOC_DPCM_STATE_OPEN:
+                return "open";
+        case SND_SOC_DPCM_STATE_HW_PARAMS:
+                return "hw_params";
+        case SND_SOC_DPCM_STATE_PREPARE:
+                return "prepare";
+        case SND_SOC_DPCM_STATE_START:
+                return "start";
+        case SND_SOC_DPCM_STATE_STOP:
+                return "stop";
+        case SND_SOC_DPCM_STATE_SUSPEND:
+                return "suspend";
+        case SND_SOC_DPCM_STATE_PAUSED:
+                return "paused";
+        case SND_SOC_DPCM_STATE_HW_FREE:
+                return "hw_free";
+        case SND_SOC_DPCM_STATE_CLOSE:
+                return "close";
+        }
+
+        return "unknown";
+}
+
+static int dpcm_state_open_file(struct inode *inode, struct file *file)
+{
+        file->private_data = inode->i_private;
+        return 0;
+}
+
+static ssize_t dpcm_show_state(struct snd_soc_pcm_runtime *fe,
+                                int stream, char *buf, size_t size)
+{
+        struct snd_pcm_hw_params *params = &fe->dpcm[stream].hw_params;
+        struct snd_soc_dpcm *dpcm;
+        ssize_t offset = 0;
+
+        /* FE state */
+        offset += snprintf(buf + offset, size - offset,
+                        "[%s - %s]\n", fe->dai_link->name,
+                        stream ? "Capture" : "Playback");
+
+        offset += snprintf(buf + offset, size - offset, "State: %s\n",
+                        dpcm_state_string(fe->dpcm[stream].state));
+
+        if ((fe->dpcm[stream].state >= SND_SOC_DPCM_STATE_HW_PARAMS) &&
+            (fe->dpcm[stream].state <= SND_SOC_DPCM_STATE_STOP))
+                offset += snprintf(buf + offset, size - offset,
+                                "Hardware Params: "
+                                "Format = %s, Channels = %d, Rate = %d\n",
+                                snd_pcm_format_name(params_format(params)),
+                                params_channels(params),
+                                params_rate(params));
+
+        /* BEs state */
+        offset += snprintf(buf + offset, size - offset, "Backends:\n");
+
+        if (list_empty(&fe->dpcm[stream].be_clients)) {
+                offset += snprintf(buf + offset, size - offset,
+                                " No active DSP links\n");
+                goto out;
+        }
+
+        list_for_each_entry(dpcm, &fe->dpcm[stream].be_clients, list_be) {
+                struct snd_soc_pcm_runtime *be = dpcm->be;
+                params = &dpcm->hw_params;
+
+                offset += snprintf(buf + offset, size - offset,
+                                "- %s\n", be->dai_link->name);
+
+                offset += snprintf(buf + offset, size - offset,
+                                "   State: %s\n",
+                                dpcm_state_string(be->dpcm[stream].state));
+
+                if ((be->dpcm[stream].state >= SND_SOC_DPCM_STATE_HW_PARAMS) &&
+                    (be->dpcm[stream].state <= SND_SOC_DPCM_STATE_STOP))
+                        offset += snprintf(buf + offset, size - offset,
+                                "   Hardware Params: "
+                                "Format = %s, Channels = %d, Rate = %d\n",
+                                snd_pcm_format_name(params_format(params)),
+                                params_channels(params),
+                                params_rate(params));
+        }
+
+out:
+        return offset;
+}
+
+static ssize_t dpcm_state_read_file(struct file *file, char __user *user_buf,
+                                size_t count, loff_t *ppos)
+{
+        struct snd_soc_pcm_runtime *fe = file->private_data;
+        ssize_t out_count = PAGE_SIZE, offset = 0, ret = 0;
+        char *buf;
+
+        buf = kmalloc(out_count, GFP_KERNEL);
+        if (!buf)
+                return -ENOMEM;
+
+        if (fe->cpu_dai->driver->playback.channels_min)
+                offset += dpcm_show_state(fe, SNDRV_PCM_STREAM_PLAYBACK,
+                                        buf + offset, out_count - offset);
+
+        if (fe->cpu_dai->driver->capture.channels_min)
+                offset += dpcm_show_state(fe, SNDRV_PCM_STREAM_CAPTURE,
+                                        buf + offset, out_count - offset);
+
+        ret = simple_read_from_buffer(user_buf, count, ppos, buf, offset);
+
+        kfree(buf);
+
+        return ret;
+}
+
+static const struct file_operations dpcm_state_fops = {
+        .open = dpcm_state_open_file,
+        .read = dpcm_state_read_file,
+        .llseek = default_llseek,
+};
+
+int soc_dpcm_debugfs_add(struct snd_soc_pcm_runtime *rtd)
+{
+        rtd->debugfs_dpcm_root = debugfs_create_dir(rtd->dai_link->name,
+                        rtd->card->debugfs_card_root);
+        if (!rtd->debugfs_dpcm_root) {
+                dev_dbg(rtd->dev,
+                         "ASoC: Failed to create dpcm debugfs directory %s\n",
+                         rtd->dai_link->name);
+                return -EINVAL;
+        }
+
+        rtd->debugfs_dpcm_state = debugfs_create_file("state", 0644,
+                                                rtd->debugfs_dpcm_root,
+                                                rtd, &dpcm_state_fops);
+
+        return 0;
+}
+#endif