[PATCH -next] ALSA: pcm: use DEVICE_ATTR_RO macro

[YueHaibing]

Use DEVICE_ATTR_RO() helper instead of plain DEVICE_ATTR(),
which makes the code a bit shorter and easier to read.

Signed-off-by: YueHaibing <yuehaibing at huawei.com>
---
 sound/core/pcm.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/sound/core/pcm.c b/sound/core/pcm.c
index b163164a83ec..6fd3677685d7 100644
--- a/sound/core/pcm.c
+++ b/sound/core/pcm.c
@@ -1004,7 +1004,7 @@ void snd_pcm_detach_substream(struct snd_pcm_substream *substream)
 	substream->pstr->substream_opened--;
 }
 
-static ssize_t show_pcm_class(struct device *dev,
+static ssize_t pcm_class_show(struct device *dev,
 			      struct device_attribute *attr, char *buf)
 {
 	struct snd_pcm_str *pstr = container_of(dev, struct snd_pcm_str, dev);
@@ -1024,7 +1024,7 @@ static ssize_t show_pcm_class(struct device *dev,
 	return sprintf(buf, "%s\n", str);
 }
 
-static DEVICE_ATTR(pcm_class, 0444, show_pcm_class, NULL);
+static DEVICE_ATTR_RO(pcm_class);
 static struct attribute *pcm_dev_attrs[] = {
 	&dev_attr_pcm_class.attr,
 	NULL
-- 
2.17.1