ASoC: soc-component: add snd_soc_pcm_component_copy_user()

Current ALSA SoC is directly using component->driver->ops->xxx,
thus, the code nested deeply, and it makes code difficult to read,
and is not good for encapsulation.

We want to implement component related function at soc-component.c,
but, some of them need to care whole snd_soc_pcm_runtime (= rtd)
connected component.

Let's call component related function which need to care with
for_each_rtdcom() loop as snd_soc_pcm_component_xxx().
This patch adds new snd_soc_pcm_component_copy_user() and use it.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Link: https://lore.kernel.org/r/87pnlx4d0a.wl-kuninori.morimoto.gx@renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/soc-component.c

@@ -462,3 +462,24 @@ int snd_soc_pcm_component_ioctl(struct snd_pcm_substream *substream,
 
 	return snd_pcm_lib_ioctl(substream, cmd, arg);
 }
+
+int snd_soc_pcm_component_copy_user(struct snd_pcm_substream *substream,
+				    int channel, unsigned long pos,
+				    void __user *buf, unsigned long bytes)
+{
+	struct snd_soc_pcm_runtime *rtd = substream->private_data;
+	struct snd_soc_rtdcom_list *rtdcom;
+	struct snd_soc_component *component;
+
+	for_each_rtdcom(rtd, rtdcom) {
+		component = rtdcom->component;
+
+		/* FIXME. it returns 1st copy now */
+		if (component->driver->ops &&
+		    component->driver->ops->copy_user)
+			return component->driver->ops->copy_user(
+				substream, channel, pos, buf, bytes);
+	}
+
+	return -EINVAL;
+}